Plant Ecol (2007) 191:221–252
DOI 10.1007/s11258-006-9239-8
ORIGINAL PAPER
Zonobiomes, zonoecotones and azonal vegetation
along the Pacific coast of North America
M. Peinado Æ J. L. Aguirre Æ J. Delgadillo Æ
M. Á. Macı́as
Received: 20 October 2005 / Accepted: 10 November 2006 / Published online: 11 January 2007
Springer Science+Business Media B.V. 2007
Abstract In this study of the Pacific coast of
North America, from Baja California to Alaska,
we evaluated the hypothesis that the floristic
composition of azonal vegetation determines
areas and distribution limits similar to those of
the corresponding zonobiomes (ZB), and does so
in response to the same macroclimatic changes
occurring on the continental scale. To this end,
686 vascular plants of the different habitats found
in 279 sites along this coastal strip were recorded.
Using an objective classification system (Average
Linkage Clustering) and factorial analysis, floristic data acquired in fieldwork were classified into
groups, which were in turn related to regional
macroclimates. Our main finding was that the
M. Peinado (&)
Departamento de Biologı́a Vegetal,
Universidad de Alcalá, Alcalá de Henares,
Madrid 28871, Spain
e-mail: [email protected]
J. L. Aguirre
Cátedra de Medio Ambiente, Universidad de Alcalá,
Alcalá de Henares, Madrid 28871, Spain
J. Delgadillo
Herbario BCMEX, Universidad Autónoma
de Baja California, Ensenada, BC, Mexico
M. Á. Macı́as
Departamento de Ciencias Ambientales,
Universidad de Guadalajara, Guadalajara,
Jalisco, Mexico
azonal coastal vegetation follows a distribution
model that is closely linked to the corresponding
macroclimate. The four ZB of the northern
Pacific coast show a flora and azonal vegetation
characteristic to each zonobiome; the latitudinal
limits of the azonal vegetation practically coinciding with those already established for the zonal
vegetation. The Boreal and Temperate ZB show
high percentages of broadly distributed elements.
The floristically richest zonobiome in terms of
endemic taxa is the Mediterranean zonobiome,
whereas the flora of Baja California is characterized by a high number of taxa related to
Neotropical flora, especially to those showing
links with South America. Data on the geographical distribution and habitats of the 247 most
significant coastal species are also provided.
Keywords Bioclimatology Coastal vegetation Floristic analysis Palaeogeography Phytogeography
Introduction
As the environment’s main independent factor,
climate is generally employed as the principal
basis for vegetation classification. Walter (1985)
distinguishes two large vegetation types according
to their distribution in terms of climate: zonal vegetation, inhabiting biomes distributed according
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to the macroclimate (zonobiomes [ZB]), and
azonal vegetation, influenced to a greater extent
by the soil than by the climate (pedobiomes or
edaphobiomes). Among others, azonal vegetation
comprises lithobiomes, psammobiomes, halobiomes, hydrobiomes and amphibiomes. It should be
noted that all the azonal biomes cited occur in the
coastal regions of continents: cliffs, beaches,
dunes, saltmarshes and wetlands. Thus, the coasts
of a continent can be the best laboratory to assess
whether azonal types of vegetation follow a
climatic model of zonal distribution.
Despite some excellent regional works and the
availability of good territorial floras, to date,
floristic changes in the coastal vegetation of the
North American Pacific have not been fully
established. As a preliminary survey to his studies
on the dunes of the Pacific, Cooper (1936) was the
first to report the distribution of 53 representative
plants of the shores and dunes of the coastal
strand from southeastern Alaska to El Socorro,
Baja California. Almost 40 years later, Breckon
and Barbour (1974), Macdonald and Barbour
(1974) and Barbour et al. (1975) published the
only known floristic syntheses of the beaches and
salt marshes of the North American Pacific, yet
their surveys did not include species of adjacent
habitats such as dunes, ocean-facing cliffs, shingle
beaches and other coastal environments.
Although some regional or local studies (Kumler
1963, 1969; Wiedemann 1966; Williams and
Potter 1972; McBride and Stone 1976; Johnson
1977; Barbour and Johnson 1988; Klinka et al.
1995) have established the distribution and ecology of the plants appearing in other coastal
habitats, so far there have been no syntheses
made on the distribution of the plants of these
habitats in the northern Pacific region.
In some of our previous publications, we related
the climax vegetation of western North America to
bioclimatic variation (Peinado et al. 1997a). In
these studies, we were able to establish the limits of
Pacific ZB using the zonal climax vegetation as
indicator (Peinado et al. 1994a, 1997b), and identify the climatic similarities that produce an almost
identical zonation model in the saltmarshes of
California, Baja California and the European
Mediterranean (Peinado et al. 1995b), as well as
in tropical mangroves (Peinado et al. 1995c).
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Plant Ecol (2007) 191:221–252
The present study was designed to explore the
floristic variation along the coast of the North
American Pacific, from Baja California to Alaska.
Its aim was twofold: on the one hand, we
evaluated the distribution and habitat of the
vascular plants appearing in the coastal edaphobiomes of the North American Pacific; and on the
other, having established the distribution pattern,
we tried to determine whether there was any
relationship between floristic changes in the
azonal vegetation and the latitudinal zonal climatic variation occurring in this coastal strip, a
variation whose effects on the climax vegetation
had been previously analysed.
Study area
Facing the Pacific Ocean, the study area extends
over 7,000 km from Cook Inlet, Alaska
(6130¢ N), to the southern tip of Baja California
(2302¢ N). In longitude, the area reaches its
western limit on Kodiak Island, at 15234¢ W,
while the easternmost site sampled was
10934¢ W, on Bahı́a de Las Palmas, Baja
California Sur. The whole area forms part of the
largest and highest of North American physiographic systems, the Pacific Border System
(Brouillet and Whetstone 1993), which is the
backdrop for most of the ocean’s shores (Fig. 1).
Four ZB can be distinguished along this latitudinal band: ZB-VIII (Boreal), ZB-V (Temperate),
ZB-IV (Mediterranean) and ZB-III or Tropical
(Walter 1985; Peinado et al. 1994a, 1997b). Two
transitional zones or zonoecotones occur between
the California–Oregon border (Mediterranean–
temperate zonoecotone) and around 30, near El
Rosario, Baja California (Mediterranean–tropical
zonoecotone). These zonoecotones show a
marked floristic and endemic richness (Peinado
et al. 1994a, 1995a, 1997b).
From a phytogeographical standpoint, Dice
(1943) included the boreal and the temperate
climate zones within the Hudsonian (continental
boreal), Sitkan (oceanic boreal) and Oregonian
(temperate) provinces. The Mediterranean zone
corresponds to the Californian Region (RivasMartı́nez et al. 1999), in which the provinces
Northern California, Southern California and
Plant Ecol (2007) 191:221–252
223
Fig. 1 Physiographic map
of the North American
Pacific basin. (Lower-left)
Main phytogeographical
units of the study area. 1.
Aleutian province; 2.
Sitkan province; 3.
Oregonian province; 4.
Californian region
(Provinces: 4a. Northern
Californian; 4b. Southern
Californian; 4c.
Martirense; 4d.
Nevadian). 5. Baja
Californian province; 6.
Sanlucan province; 7.
Hudsonian province.
After Dice (1943)
modified
Martirense have been defined (Peinado et al.
1994b). The tropical zone corresponds to the
Xerophytic-Mexican region (Rzedowski 1978),
which was divided into two provinces: Baja
Californian and Sanlucan (Peinado et al. 1994b).
The map provided in Fig. 1 is based on Dice’s
(1943) classification with the modifications suggested in this article.
Materials and methods
Before conducting the fieldwork, we selected sites
along the Pacific coast, including the islands
Kodiak and Vancouver. These sites were selected
a priori to ensure an accessible azonal vegetation
that was relatively well preserved. As considered
here, azonal vegetation types are those influenced
to a greater extent by the soil than by climate
(Walter 1985), and include typical coastal vegetation types such as those inhabiting lithobiomes
(ocean-facing cliffs), psammobiomes (beaches
and dunes), halobiomes (saltmarshes and areas
of vegetation types influenced more or less
directly by exposure to air-borne salts) and
amphibiomes (wetlands).
Site selection was based on a bibliographical
and cartographical review. Cartographies were
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used to search for toponymic references such as
beaches, cliffs, saltmarshes or wetlands or to
select natural protected zones such as national
and state forests and parks, wilderness areas or
wildlife refuges. In the subsequent fieldwork, we
found that not all the sites selected fulfilled the
minimal conservation conditions for significant
sampling of the vegetation. Vice-versa, during the
fieldwork, we included new sites proposed by
local naturalists or members of the nature conservation organizations of the different countries
and states visited.
These sites were then assigned to a particular
climate type. To do this, available data from 104
meteorological stations were used: Müller (1982),
for the stations of British Columbia; NOAA
(2002) for the US stations; and Reyes et al.
(1990) and Delgadillo (1995) for those of Baja
California. Every station was classified using the
climatic systems of Köppen and Troll & Paffen (in
Müller 1982), Rivas-Martı́nez (2004) and Walter
and Lieth (1967). Accordingly, each station was
ascribed to one of Troll and Paffen’s climate
zones: Boreal, Temperate, Mediterranean or
Tropical. The sites were in turn assigned to a
meteorological station and therefore to a climate
zone according to their geographical proximity.
The aim of the fieldwork was to draw up lists of
plants for each site. To this end, habitats were
differentiated in each site on the basis of physical
features, the physiognomy and structure of the
vegetation and species dominance. In each habitat, we selected a plot of size based on the
concept of the minimum area of relatively uniform stands (Westhoff and van der Maarel 1973).
To assess the abundance and dominance of the
vascular plants in their respective habitats, phytosociological relevés were taken in each plot
according to the Braun-Blanquet approach
(Braun-Blanquet 1979). A total of 279 sites were
finally sampled (Fig. 2), in which 965 relevés were
conducted comprising 381 genera and 686 infrageneric taxa. The exact locations of these sites are
provided in Appendix 1.
The next step was to recompile the information
available for the distribution area of each taxon
recorded in the field. To do this, bibliographical
sources were used (Cooper 1936; Peck 1941;
Hultén 1968; Calder and Taylor 1968; Munz and
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Plant Ecol (2007) 191:221–252
Keck 1973; Macdonald and Barbour 1974;
Barbour et al. 1975; Breckon and Barbour 1974;
Good 1974; Johnson 1977; Abrams and Ferris
1980; Wiggins 1980; Beauchamp 1986; Barbour
and Johnson 1988; Hickman 1993; MacKinnon
et al. 1994; Pojar and MacKinnon 1994;
Delgadillo 1995; Klinka et al. 1995; Mabberley
2002; Flora of North America 1993–2005) along
with distribution maps obtained from the 2004
versions of the databases: CalFlora (2004),
Klinkenberg and USDA (2005).
According to their global distributions, each of
the registered taxa was assigned to one of the six
phytogeographical elements: Cosmopolitan, Holarctic, Introduced, Discontinuous, North American and Tropical. We have defined cosmopolitan
as plants whose distribution ranges extend across
the major part of both tropical and extratropical
regions of the world. We used the term Holarctic
according to the sense employed by Takhtajan
(1986). The category Introduced includes nonnative species. The element Discontinuous (sensu
Good 1974) was further divided into two subelements: North American–Eastern Asian and
North American–South American. The North
American–Eastern Asian subelement is constituted by Amphi-Beringian taxa. The North
American–South American subelement includes
taxa whose distribution is mainly restricted to the
Americas, but excludes taxa showing an essentially tropical distribution; these have been
ascribed to the Neotropical subelement.
The North American element was split into
nine subelements: North American sensu strictu,
Western North American, Boreal Northwestern
Pacific, Temperate Northwestern Pacific, Pacific
Coast, Madrean, Mediterranean, Sonoran and
Baja Californian. North American sensu strictu
are those taxa widely distributed throughout
North America including Greenland and Mexico.
Within the Western North American subelement,
we included taxa whose distribution ranges lie
west of the Rocky Mountains, but that are not so
restricted as to be included in other North
American endemic categories. The Boreal Northwestern Pacific subelement includes endemic
plants of the boreal coast of Alaska, although
some may reach the extreme north of British
Columbia. Within the Temperate Northwestern
Plant Ecol (2007) 191:221–252
225
Fig. 2 Location of the
sites sampled (see
Appendix 1)
Pacific subelement, we included species whose
distribution is confined to the temperate coastal
zones between southern Oregon and northern
British Columbia. Other species distributed along
the Pacific coast across more than one climatic
zone, constitute the Pacific Coast subelement.
Given the huge extension of the Madrean
region and its floristic richness, we distinguished
four endemic subelements: Madrean, Mediterranean, Sonoran and Baja Californian, the last
including plants endemics to the tropical part of
Baja California. Madrean taxa are those occurring in both Mediterranean and tropical climate
areas. Those taxa whose distribution area is
mainly restricted to the Mediterranean climate
zone form the Mediterranean endemic subelement, whereas the Sonoran endemic subelement
includes plants of wide distribution in the Sonoran province.
Into the Tropical element we distinguished
three subelements: Pantropical, including taxa
appearing in all three tropical zones; AmphiAtlantic tropical, containing taxa distributed
across the tropical zones of both coasts of the
Atlantic Ocean; and the Neotropical subelement
including those taxa whose geographical
distributions are mainly restricted to tropical
America.
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With the data obtained in the field, a double
entry matrix (sites and species) was constructed,
in which the cover/abundance values of the
Braun-Blanquet scale were transformed into a
binary scale of presence (value 1) or absence
(value 0). This matrix was used to order the data
using SPSS 12.0 software. Clusters (Average
Linkage Clustering between groups with rescaled
distance cluster combine) were defined as indicated by major discontinuities. This was followed
by a factorial analysis (Principal Coordinates
Analysis) between clusters, in which species were
scored as presence percentages in each group.
Plant nomenclature follows Kartesz (1994),
except for Baja California (Wiggins 1980).
Results
Climatic results
Figure 3 shows the most relevant climatic trends
obtained from a group of 83 stations representative of those analysed. The coast from Alaska to
approximately Prince Rupert (British Columbia)
has a boreal climate with moderately warm
summers and cold winters. Within this boreal
macroclimate there are two groups of stations: the
continental boreal or microthermal stations of
Köppen’s classification and the oceanic boreal or
mesothermal stations, whose rainfall can be up to
10 times higher. Twenty-three of the sites sampled (sites 257–279) were ascribed to the boreal
zone.
From Prince Rupert southwards, the temperate
climate dominates until we reach south Oregon.
However, there are two exceptions: (a) stations
such as Vancouver, Olga, Seattle-Tacoma, etc.,
located inland around the Puget Sound and in the
rain shadow of the Olympic Mountains show
Mediterranean climograms; and (b), along the
outer Pacific coast, from North Bend (4325¢ N)
to northern California, Mediterranean and temperate climate stations are interspersed in an area
considered a Mediterranean–temperate zonoecotone (Walter 1985, p. 41). The influence of the
Mediterranean climate becomes clear from parallel 42 since in this zonoecotone summer
drought is compensated by extended periods of
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Plant Ecol (2007) 191:221–252
cloudiness and fog that greatly reduce evaporation (Peinado et al. 1997b). Hence, 17 of the
coastal sites sampled (sites 178–195) may be
assigned to this transition zone, while the rest of
the stations between Coos Bay, Oregon,
and Prince Rupert (sites 196–256) are clearly
temperate.
The Mediterranean climate uninterruptedly
spans from Eureka, California to El Rosario,
Baja California, where the Mediterranean–tropical ecotone commences (Walter 1985; Peinado
et al. 1995a). North of parallel 31 (near Cabo
Colonet), all stations show Mediterranean climograms and south of El Rosario (30) all stations
show tropical desert climograms. However, stations situated between Cabo Colonet and El
Rosario show intermediate conditions, since the
arid period lasts nine months and there is a short
period (December, January, February) in which
the rainfall line slightly exceeds the temperature
line, sufficient nevertheless to consider these
stations Mediterranean. Overall, 86 sites (91–
177, except site 103, San Felipe, on the tropical
Gulf of California coast) may be described as
clearly Mediterranean. Sites 1–90 are related to
tropical stations within a zone of the Baja
California peninsula and were placed by Walter
(l.c.) in his Tropical Zonobiome.
Classification and ordination results
Figure 4 shows the dendrogram obtained using
the matrix of 279 sites, which appear as six large
groups. According to the geographic location of
the sites and their assignment to a climate, four of
the groups correspond each to a zonobiome (ZBVIII, Boreal; ZB-V, Temperate; ZB-IV, Mediterranean; and ZB-III or Tropical), and two
groups to transition zones or zonoecotones
(ZEC-1 or Mediterranean–temperate and ZEC2 or Mediterranean–tropical). The four ZB were,
in turn, divided into subgroups. To identify the
floristic composition of these groups and subgroups, a synthetic table was created by scoring
species as presence percentages in each group and
subgroup. A summary of this table showing the
most significant differences among subgroups is
provided as Table 1. This table was then used for
a factorial analysis in which two factors explaining
Plant Ecol (2007) 191:221–252
227
Fig. 3 Main relevant climatic trends for 83 selected
stations along the study area. Above: T, mean year
temperature (C); m, mean monthly minimum tempera-
ture of the coldest month (C); %SumP, percentage of
summer precipitation (mm). Beneath: P, annual precipitation (mm)
41% of the variance were defined. The results
served to spatially discriminate the groups, maintaining the Zonoecotone groups as nodes (Fig. 5).
Table 2 shows the phytogeographical elements
grouping plants of ZB, zonoecotones and subgroups. Tables 3–5 reflect main floristic differences between adjacent ZB. These summary
tables only provide data corresponding to the
most significant coastal plants. In these tables, the
term ‘‘differential taxa’’ is used to refer to those
plants that, without being endemic to a particular
phytogeographic unit, serve to floristically differentiate it from a neighbouring unit lacking these
differential taxa.
Discussion
Group ZB-VIII included the 23 Alaskan sites
distributed as two subgroups. When the sites in
subgroup BOR-1 are projected onto a map, they
clearly take up their positions along Cook Inlet,
the only area of North America where the boreal
taiga reach the Pacific Ocean (Dice 1943; Bailey
1995). The climate there is continental boreal and
plants endemic or exclusive to this subgroup exist
that are absent from the BOR-2 subgroup
(Table 1). The sites of subgroup BOR-2 extend
along the open coast of the Pacific, under an
oceanic boreal climate and across an area where
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Plant Ecol (2007) 191:221–252
Fig. 4 Dendrogram obtained by Average Linkage Clustering (rescaled distance cluster combine) of 279 sites. n: number of
sites in each group
woods of Picea sitchensis dominate the coast.
These woods do not exist in the sites of subgroup
BOR-1, because in Cook Inlet they are replaced
with the Hudsonian forests dominated by white
spruce, Picea glauca. The flora associated with
both types of coastal woods also mark notable
differences between the subgroups BOR-1
(Dice’s Hudsonian province) and BOR-2 (Dice’s
Sitkan province).
The separation between boreal ZB-VIII and
temperate ZB-V seems clear, both at the climatic
and floristic or ecological, levels. Most of the
phytogeographical classification schemes and
maps coincide in distinguishing floristic or ecological units that are replaced at the latitude of
Dixon Entrance, just north of the Queen
Charlotte Islands, where Dice located the border
between the boreal Sitkan and the temperate
Oregonian provinces (Udvardy 1975a, b; Walter
1985; Bailey 1995; Peinado et al. 1997a, b; Brown
et al. 1998; Rivas-Martı́nez et al. 1999). However,
there is a common floristic background in both
ZB, chiefly when the oceanic boreal subgroup
BOR-2 is compared to ZB-V subgroups containing Sitka spruce woods. Sitka spruce forests thrive
on the most foggy and rainy coasts of the ZB VIII
and V, in the area with the highest records of
precipitation in western North America. Despite
the common floristic background of these coastal
forests from Alaska to Oregon, there are also
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significative floristical differences between the
oceanic boreal (subgroup BOR-2) and temperate
(subgroup TEM-5) coastal forests. The former
belong to the association Lycopodium annotinum–Tsuga mertensiana and the latter to the
association Poystichum munitum–Picea sitchensis
(Peinado et al. 1997a).
The absence of shore pine (P. contorta var.
contorta) forests in boreal areas is another difference between ZB-VIII and ZB-V coasts. The
northernmost location with isolated shore pines
that we know is Gustavus in Glacier Bay National
Park, Alaska, at 5823¢ N, and shore pine has
been reported as far north as Yakutat, 5931¢ N
(Viereck and Little 1991), i.e., five degrees north
of the northernmost border of the ZB-V. However, in both cases the pines do not form dune
forests, rather they appear as dwarf forms thriving
on open muskegs of peat moss and on benches
near lakes. Table 3 also indicates the floristic
differences in some of the types of vegetation
shared by both zones (beach and foredune vegetation; intertidal saltmarshes and estuarine wetlands), as well as the existence of types of
differential vegetation in ZB-V (dune forests
and interdune grasslands) or ZB-VIII (Picea
glauca woods and mud flats).
ZB-V included 69 of the 70 sites found in
Oregon, Washington and British Columbia, and
10 sites in northwestern California. One southern
Boreal species group
Betula papyrifera var. kenaica BOR
Puccinellia hultenii BOR
Senecio pseudoarnica NAE
Conioselinum gmelinii NAE
Ligusticum scoticum ssp. hultenii BOR
Stellaria humifusa HOL
Poa eminens BOR
Lathyrus palustris NOA
Equisetum sylvaticum HOL
Viburnum edule NOA
Empetrum nigrum HOL
Geocaulon lividum NOA
Linnaea borealis ssp. americana NOA
Picea glauca NOA
Rosa acicularis ssp. acicularis HOL
Shepherdia canadensis NOA
Vaccinium uliginosum HOL
Dendranthema arcticum ssp. arcticum NAE
Atriplex alaskensis BOR
Athyrium filix-femina ssp. cyclosorum NOA
Lycopodium annotinum HOL
Menziesia ferruginea WES
Oplopanax horridum NOA
Orthilia secunda HOL
Sorbus sitchensis WES
Tiarella trifoliata WES
Vaccinium membranaceum NOA
Mertensia maritima HOL
Boreo-temperate species group
Carex lyngbyei HOL
Picea sitchensis PAC
Deschampsia cespitosa ssp. beringensis NAE
Festuca rubra ssp. rubra COS
Hordeum brachyantherum NOA
II
III
IV
V
V
III
III
IV
III
III
IV
III
V
V
V
V
V
V
V
V
V
III
II
V
V
II
III
III
V
V
V
V
V
V
V
V
III
IV
IV
IV
III
III
III
III
II
I
r
IV
IV
V
I
II
III
V
III
IV
I
2
136
19
37
1
91
12
21
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
2
73
12
26
TEM
BOR
Cluster subgroups
ZB-V
ZB-VIII
Zonobiomes and zonoecotones
I
V
3
32
6
12
IV
IV
III
II
4
80
9
18
r
I
IV
I
5
81
16
11
r
I
6
74
17
6
II
II
II
II
82
4
35
ZEC-1
1
50
12
14
2
125
19
23
MED
ZB-IV
Table 1 Frequency of taxa in sampled sites: summary of results obtained by Average Linkage Clustering
3
68
9
18
4
23
5
8
5
120
8
34
6
147
11
21
7
98
9
29
117
14
29
ZEC-2
1
135
27
22
TRO
2
58
17
16
ZB-III
3
78
18
26
4
111
24
17
Plant Ecol (2007) 191:221–252
229
123
123
1
91
12
21
2
73
12
26
IV
IV
IV
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
III
Lathyrus japonicus var. maritimus NAS
III
Honkenya peploides ssp. major NAE
IV
Plantago maritima var. juncoides HOL
Temperate species group
Gaultheria shallon PAC
Vaccinium ovatum PAC
Sarcocornia perennis HOL
Cakile edentula ssp. edentula var. edentula NOA
Arctostaphylos uva-ursi HOL
Anaphalis margaritacea HOL
Glaux maritima HOL
Cytisus scoparius INT
Tsuga heterophylla WES
Hypochaeris radicata INT
Lupinus littoralis PAC
Poa confinis PAC
Temperate-northern Mediterranean species group
Baccharis pilularis MED
Ammophila arenaria INT
Polystichum munitum WES
Salix hookeriana PAC
Lonicera involucrata var. involucrata NOA
Pinus contorta var. contorta PAC
Carex obnupta PAC
Alnus rubra WES
Tanacetum camphoratum PAC
Juncus falcatus COS
Spiranthes romanzoffiana NOA
Veronica scutellata NOA
Cardionema ramosissimum NAS
Phacelia argentea MED
Armeria maritima ssp. californica PAC
Polygonum paronychia PAC
Myrica californica PAC
II
I
II
II
I
I
I
r
r
II
III
III
II
V
III
IV
III
IV
V
I
III
IV
II
III
III
5
81
16
11
I
III
II
IV
IV
III
III
II
I
II
II
II
IV III
I
III
I
I
III
IV
ZEC-1
II
r
r
r
r
I
I
IV r
r
I
I
r
r
II I
V
V
III
III
III
II
III
III
IV
III
III
II
III
III
IV
IV
III
6
74 82
17 4
6 35
IV III I
III III
I
I
II I
I
III II I
V I
r
III
I
III
II
II
V
V
III
III
V
r
r
II
IV
IV
IV
II
IV
III
II
II
III
r
V
IV
III
IV I
I
I
4
80
9
18
III V
r
II
V II
2 3
136 32
19 6
37 12
TEM
BOR
Cluster subgroups
ZB-V
ZB-VIII
Zonobiomes and zonoecotones
Table 1 continued
r
r
II
II
I
r
I
r
I
I
III
IV
I
II
I
IV
1
2 3
50 125 68
12 19 9
14 23 18
MED
ZB-IV
I
I
IV
I
I
V
II
I
II
I
4
5
6 7
23 120 147 98 117
5
8 11 9 14
8 34 21 29 29
ZEC-2
1 2
3
4
135 58 78 111
27 17 18 24
22 16 26 17
TRO
ZB-III
230
Plant Ecol (2007) 191:221–252
Calystegia soldanella COS
Carex pansa PAC
Northern Mediterranean species group
Camissonia cheiranthifolia ssp.cheiranthifolia MED
Artemisia pycnocephala MED
Erigeron glaucus MED
Salix lasiolepis MAD
Eriogonum latifolium MED
Ericameria ericoides MED
Eriophyllum stoechadifolium MED
Lupinus arboreus PAC
Eriogonum parvifolium MED
Corethrogyne californica var. californica MED
Grindelia hirsutula var. maritima MED
Toxicodendron diversilobum WES
Southern Mediterranean species group
Lotus scoparius var. scoparius MED
Nassella lepida MED
Dudleya lanceolata MAD
Lupinus chamissonis MED
Erigeron blochmaniae MED
Senecio blochmaniae MED
Dudleya caespitosa MED
Conicosia pugioniformis INT
Viguiera laciniata MAD
Agave shawii ssp. shawii MED
Opuntia littoralis MED
Rhus integrifolia MED
Encelia californica var. californica MAD
Mirabilis californica MED
Rosa minutifolia BAJ
Bergerocactus emoryi MED
Amblyopappus pusillus MED
Cneoridium dumosum MED
Eriogonum fasciculatum var. fasciculatum MED
III
I
I
I
I
I
r
r
I
r
r
II
V
V
III
II
IV
V
III
1
2 3 4 5 6
91 136 32 80 81 74 82
12 19 6 9 16 17 4
21 37 12 18 11 6 35
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
2
73
12
26
TEM
BOR
Cluster subgroups
ZEC-1
ZB-VIII ZB-V
Zonobiomes and zonoecotones
Table 1 continued
ZEC-2
r
I
r
I
III
III
III
r
IV
II
IV
II
I
I
I
I
I
II
r
I
III
II
I
IV
III
IV
III
III
II
II
I
II
II
IV
II
r
r
II
r
I
IV
II
I
II
V
I
IV
IV
II
IV
V
III I
IV
II V
II
V
I
II
II
I
V
V
V
IV
III
II
II
IV
V
III
IV
III
III
III
V
II
III
IV
I
I
I
I
II
III
II
II
IV
IV r
IV r
V II
1
2 3 4
5
6 7
50 125 68 23 120 147 98 117
12 19 9 5
8 11 9 14
14 23 18 8 34 21 29 29
MED
ZB-IV
1 2
3
4
135 58 78 111
27 17 18 24
22 16 26 17
TRO
ZB-III
Plant Ecol (2007) 191:221–252
231
123
123
Malosma laurina MED
Acalypha californica MAD
Achnatherum diegoense MED
Dudleya campanulata MED
Dudleya cultrata BAJ
Mediterranean-Tropical species group
Sarcocornia pacifica PAC
Spartina foliosa PAC
Frankenia salina NAS
Suaeda esteroa MED
Arthrocnemum subterminale MAD
Batis maritima NAS
Monanthochloe littoralis NOA
Southern Mediterranean-Tropical species group
Abronia maritima MAD
Stenocereus gummosus SON
Croton californicus MAD
Mammillaria dioica MAD
Simmondsia chinensis MAD
Isocoma menziesii var. vernonioides MAD
Lycium brevipes MAD
Euphorbia misera MAD
Dudleya attenuata ssp. orcuttii MED
Isocoma menziesii var. menziesii MED
Helianthus niveus ssp. niveus MAD
Echinocereus maritimus BAJ
Ambrosia chenopodifolia MAD
Opuntia prolifera MED
Mesembryanthemum crystallinum INT
Atriplex canescens ssp. canescens NOA
Atriplex julacea BAJ
Frankenia palmeri MAD
Lycium andersonii MAD
Camissonia cheiranthifolia ssp. suffruticosa MED
Suaeda taxifolia MAD
r
r
III
1
2 3 4 5 6
91 136 32 80 81 74 82
12 19 6 9 16 17 4
21 37 12 18 11 6 35
2
73
12
26
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
ZEC-1
TEM
BOR
Cluster subgroups
ZB-V
ZB-VIII
Zonobiomes and zonoecotones
Table 1 continued
II
II
III
II
II
II
I
I
I
I
r
r
I
I
I
II
r
I
I
r
I
r
r
I
I
r
I
I
I
I
I
I
III
I
II
II
II
II
II
II
III
V
117
14
29
ZEC-2
I
IV
III III
r
V III
V II
I
III
I
V
IV IV
III r
I
IV
I
V
III II
III II
IV II
I
V
I
III
I
IV
I
III
II
III
III
III
III
III
III
2 3 4
5
6 7
125 68 23 120 147 98
19 9 5
8 11 9
23 18 8 34 21 29
V III
IV II
V I
III
III
III
III
1
50
12
14
MED
ZB-IV
III
I
r
r
II
I
III
III
r
I
r
r
I
r
III
III
V
V
r
r
II
II
II
I
I
I
II
II
r
r
III
I
r
r
I
r
III
V
III
III
II
I
II
II
r
4
111
24
17
II
I
r
II III
II I
III I
1 2
3
135 58 78
27 17 18
22 16 26
TRO
ZB-III
232
Plant Ecol (2007) 191:221–252
Camissonia crassifolia BAJ
Astragalus anemophilus BAJ
Tropical species group
Ambrosia ambrosioides SON
Cenchrus palmeri SON
Hymenoclea pentalepis SON
Allenrolfea occidentalis MAD
Hyptis emoryi SON
Fouquieria diguetii SON
Atriplex magdalenae BAJ
Encelia ventorum BAJ
Chaenactis lacera BAJ
Dyssodia anthemidifolia BAJ
Sphaeralcea fulva BAJ
Thermotropical species group
Maytenus phyllanthoides NEO
Opuntia cholla BAJ
Bursera microphylla SON
Sporobolus virginicus NEO
Ipomoea pes-caprae NEO
Sesuvium verrucosum MAD
Laguncularia racemosa AAT
Rhizophora mangle NEO
Avicennia germinans NEO
Sanlucan species group
Oenothera drummondii var. thalassaphila
Setaria palmeri BAJ
Cyrtocarpa edulis BAJ
Euphorbia leucophylla SON
Jouvea pilosa NEO
Lycium fremontii var. congestum SON
Proboscidea althaefolia SON
Antigonon leptopus SON
Asclepias subulata SON
Froelichia interrupta NEO
BAJ
1
2 3 4 5 6
91 136 32 80 81 74 82
12 19 6 9 16 17 4
21 37 12 18 11 6 35
2
73
12
26
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
ZEC-1
TEM
BOR
Cluster subgroups
ZB-V
ZB-VIII
Zonobiomes and zonoecotones
Table 1 continued
ZEC-2
II
III
1
2 3 4
5
6 7
50 125 68 23 120 147 98 117
12 19 9 5
8 11 9 14
14 23 18 8 34 21 29 29
MED
ZB-IV
IV
II
IV
IV
IV
II
r
III
II
II
II
IV
r
IV
IV
I
V
V
I
V
I
II
I
r
III
V
V
V
V
V
IV
V
V
III
V
IV
IV
IV
IV
IV
IV
I
I
V
V
V
V
V
II
I
1 2
3
135 58 78
27 17 18
22 16 26
TRO
ZB-III
r
V
II
II
II
II
II
r
r
r
IV
r
r
II
r
I
r
r
I
V
V
V
II
V
r
II
4
111
24
17
Plant Ecol (2007) 191:221–252
233
123
123
BAJ
IV
V
II
II
V
V
IV
IV
II
III
r
r
III V
III IV
II III
III II
II V
I
V III
V
V II
V
I
V
I
I
II
I
III
II
I
I
I
V
II
82
4
35
III
III
IV
II
III II
I
IV
III
r
IV
r
III
III
V
III
III
r
I
r
5 6
81 74
16 17
11 6
ZEC-1
4
23
5
8
IV
IV
I
ZEC-2
III
II
V
II
I
V
III
II
II
II
II
I
I
II
r
r
r
r
I
I
V
I
r
I
r
r
r
III
II
I
5
6 7
120 147 98 117
8 11 9 14
34 21 29 29
II
III II
I
II I
II IV
III IV
I
2 3
125 68
19 9
23 18
IV II
II IV
I
IV
I
III
IV
IV
III
r
IV
III
II
IV
III I
r
1
50
12
14
MED
ZB-IV
I
r
III
III
II
II
V
II
II
II
II
II
1 2
3
135 58 78
27 17 18
22 16 26
TRO
ZB-III
r
r
r
r
4
111
24
17
Frequencies appear as percentage classes. V: species occurring in 81–100% of sites; IV: 61–80%; III: 41–60%; II: 21–40%; I: 11–20%; r: < 10%. Species abbreviations
(phytogeographical elements): AAT, Amphi-Atlantic Tropical; AAP, Amphi-Pacific Tropical; BAJ, Bajacalifornian endemic; BOR, Boreal Northwestern Pacific
endemic; COS, Cosmopolitan; HOL, Holarctic; INT, Introduced; MAD, Madrean endemic; MED, Mediterranean endemic; NAE, North American–Eastern Asian;
NAS, North American–South American; NEO, Neotropical; NOA: North American endemic; PAC, Pacific; PAN, Pantropical; SON, Sonoran endemic; TEM,
Temperate Northwestern Pacific endemic; WES, Western North American endemic
Jatropha cordata BAJ
Portulaca pilosa NEO
Drymaria holosteoides var. crassifolia
Bursera cerasifolia BAJ
Dalea divaricata ssp. anthonyi BAJ
Cardiospermum corindum NEO
Castela peninsularis BAJ
Porophyllum porphyreum BAJ
Physalis glabra BAJ
Scaevola plumieri PAN
Widespread taxa
Distichlis spicata NOA
Cakile maritima INT
Ambrosia chamissonis NAS
Argentina egedii ssp. egedii NAE
Leymus mollis ssp. mollis NAE
Achillea millefolium HOL
Cuscuta salina WES
Fragaria chiloensis ssp. pacifica NAS
Abronia latifolia PAC
Triglochin maritimum HOL
Juncus lesueurii PAC
Jaumea carnosa WES
Limonium californicum MED
Artemisia californica MED
2 3 4
136 32 80
19 6 9
37 12 18
1
91
12
21
1
68
11
29
Number of taxa
Number of sites
Average taxa/sites
2
73
12
26
TEM
BOR
Cluster subgroups
ZB-V
ZB-VIII
Zonobiomes and zonoecotones
Table 1 continued
234
Plant Ecol (2007) 191:221–252
Plant Ecol (2007) 191:221–252
235
Fig. 5 Graph of the two principal components of the factorial analysis performed on the 20 groups obtained in the cluster
Oregon site and three sites in north California
formed the ZEC-1 group. The group ZB-V was
subdivided into six subgroups. Subgroup TEM-1
brought together sites with salt marshes and
estuarine wetlands of the temperate zone, spreading from southern Oregon to Vancouver Island.
This subgroup is strongly bound by the high
proportions of typical halophytes or subhalophytes such as Distichlis spicata, Jaumea carnosa,
Sarcocornia perennis or Triglochin maritimum.
Some of these plants are also present in the
halophile subgroup MED-1, but this last subgroup lacks Carex lyngbyei, Deschampsia cespitosa
ssp. beringensis, Festuca rubra, Glaux maritima,
Plantago maritima var. juncoides and S. perennis.
In contrast, the Mediterranean saltmarsh group
MED-1 contains some plants (Frankenia salina,
Limonium californicum, Sarcocornia pacifica and
Spartina foliosa, among others) that are absent
from the temperate saltmarshes.
The large coastal dune systems of the ZB-V
showed a high variability of habitats within
successional and zonal complexes that start with
the herbaceous communities of deflation areas
and give rise to woods on stable dunes dominated
by conifers (Kumler 1963, 1969; Wiedemann
1966; Franklin and Dyrness 1988; Klinka et al.
1995). The rest of the ZB-V subgroups reflect
these dune complexes. Subgroup TEM-2 included
19 sites between Oregon and British Columbia.
This subgroup showed the highest number of
species per site, comprising the sites with the most
complex dune systems and included woods of
Sitka spruce and shore pine, wet thickets of Salix
hookeriana and Myrica californica, dry and wet
meadows in interdune depressions and deflation
areas dominated by Juncaceae and Cyperaceae
(Carex lyngbyei, C. obnupta, C. pansa and Juncus
falcatus), and communities from beaches (Cakile
edentula) and foredunes (Ammophila arenaria,
Lathyrus japonicus var. maritimus, Leymus mollis
ssp. mollis).
Subgroup TEM-3 contained six sites in which
highest plant proportions corresponded to those
of dune forests (with sitka spruce and shore pine
as the dominant trees), and beach (C. edentula)
and foredune plants (A. arenaria, L. japonicus var.
maritimus, L. mollis ssp. mollis). These sites have
123
123
COS
8
7.3
6
8.8
3
4.1
9
4.17
8
8.8
7
5.1
1
3.1
5
6.3
3
3.7
4
5.4
7
8.5
11
3.4
2
4.0
6
4.8
0
0.0
2
8.7
5
4.2
0
0.0
0
0.0
Subelement
Zonobiome III
MED-7
MED-6
MED-5
MED-4
MED-3
MED-2
MED-1
Zonobiome IV
ZEC-1
TEM-6
TEM-5
TEM-4
TEM-3
TEM-2
TEM-1
Zonobiome V
BOR-2
BOR-1
COS
Element
25
22.9
20
29.4
17
23.3
19
8.8
13
14.3
13
9.6
3
9.4
8
10.1
5
6.2
4
5.4
3
3.7
5
1.6
2
4.0
3
2.4
1
1.5
0
0.0
3
2.5
2
1.6
0
0.0
HOL
HOL
2
1.8
1
1.5
2
2.7
8
3.7
6
6.6
7
5.1
1
3.1
9
11.4
0
0.0
10
13.5
6
7.3
12
3.7
7
14.0
10
8.0
3
4.4
5
21.7
8
6.7
5
4.0
1
1.0
NAS
11
10.1
10
14.7
8
11.0
7
3.24
5
5.5
6
4.4
1
3.1
5
6.3
3
3.7
3
4.1
3
3.7
2
0.6
1
2.0
2
1.6
1
1.5
1
4.3
2
1.7
0
0.0
0
0.0
NAE
DISCONT
22
20.2
10
14.7
16
21.9
31
14.4
10
11.0
15
11.0
2
6.3
9
11.4
18
22.2
6
8.1
9
11.0
18
5.6
5
10.0
8
6.4
3
4.4
1
4.3
6
5.0
5
4.0
2
2.0
NOA
15
13.8
5
7.4
11
15.1
49
22.7
19
20.9
26
19.1
4
12.5
10
12.7
31
38.3
15
20.3
15
18.3
23
7.2
3
6.0
11
8.8
8
11.8
2
8.7
8
6.7
6
4.8
1
1.0
WES
13
11.9
11
16.2
8
11.0
1
0.46
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
BOR
NORTH AMERICAN
0
0.0
0
0.0
0
0.0
2
0.93
2
2.2
2
1.5
0
0.0
1
1.2
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
TEM
9
8.2
4
5.9
5
6.8
39
18.1
18
19.8
31
22.8
13
40.6
18
22.8
12
14.8
15
20.3
16
19.5
24
7.5
1
2.0
21
16.8
6
8.8
2
8.7
11
9.2
4
3.2
0
0.0
PAC
0
0.0
0
0.0
0
0.0
3
1.39
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
3
3.7
37
11.5
8
16.0
4
3.2
2
2.9
2
8.7
10
8.4
25
20.2
26
26.5
MAD
0
0.0
0
0.0
0
0.0
11
5.09
0
0.0
2
1.5
0
0.0
6
7.5
5
6.2
12
16.2
12
14.6
131
40.8
14
28.0
38
30.4
34
50.0
4
17.4
51
42.9
60
48.4
44
44.9
MED
0
0.0
0
0.0
0
0.0
0
0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
7
2.2
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
2
1.6
7
7.1
SON
0
0.0
0
0.0
0
0.0
0
0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
11
3.4
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
6
4.8
10
10.2
BAJ
0
0.0
0
0.0
0
0.0
0
0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
1
0.3
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
1
0.8
1
1.0
PAN
0
0.0
0
0.0
0
0.0
0
0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
AAT
TROPICAL
0
0.0
0
0.0
0
0.0
0
0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
1
0.3
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
1
1.0
NEO
4
3.7
1
1.5
3
4.1
37
17
10
11.0
27
19.9
7
21.9
8
10.0
4
4.9
5
6.8
8
9.8
38
11.8
7
14.0
22
17.6
10
14.7
4
17.4
15
12.6
8
6.5
5
5.1
INT
INT
109
100
68
100
73
100
216
100
91
100
136
100
32
100
79
100
81
100
74
100
82
100
321
100
50
100
125
100
68
100
23
100
119
100
124
100
98
100
Total
Table 2 Summarized data for the number of infra-generic taxa on each cluster group and subgroup according to phytogeographical elements and subelements
(columns)
236
Plant Ecol (2007) 191:221–252
Total
TRO-4
TRO-3
TRO-2
TRO-1
Zonobiome III
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
16
2.3
ZEC-2
Abbreviations as for Table 1. Top line of each row gives the number of taxa and second line gives the percentage of the total number of taxa (last column)
19
16.2
6
2.7
4
3.0
2
3.4
1
1.3
1
0.9
60
8.7
0
0.0
20
8.9
9
6.7
8
13.8
14
18.2
15
14.0
21
3.1
0
0.0
1
0.4
0
0.0
1
1.7
0
0.0
1
0.9
1
0.1
0
0.0
3
1.3
1
0.7
0
0.0
1
1.3
2
1.8
4
0.6
20
17.1
70
31.1
33
24.4
8
13.8
30
39.0
36
32.7
78
11.4
7
6.0
63
28.0
38
28.1
21
36.2
19
24.7
35
31.8
66
9.6
23
19.7
11
4.9
11
8.1
2
3.4
0
0.0
0
0.0
136
19.8
34
29.1
32
14.2
27
20.0
11
19.0
6
7.7
11
9.9
51
7.4
2
1.7
3
1.3
1
0.7
0
0.0
0
0.0
0
0.0
53
7.7
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
2
0.3
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
13
1.9
2
1.7
3
1.3
2
1.5
0
0.0
2
2.6
1
0.9
67
9.8
5
4.3
6
2.7
5
3.7
2
3.4
2
2.6
2
1.8
55
8.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
13
1.9
5
4.3
7
3.1
4
3.0
3
5.2
2
2.6
6
5.4
17
2.5
AAT
PAN
BOR
WES
NOA
NAE
NAS
COS
Subelement
HOL
COS
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
0
0.0
33
4.8
INT
117
100
225
100
135
100
58
100
77
100
110
100
686
100
237
Element
Table 2 continued
HOL
DISCONT
NORTH AMERICAN
TEM
PAC
MAD
MED
SON
BAJ
TROPICAL
NEO
INT
Total
Plant Ecol (2007) 191:221–252
mature woods in direct contact with the beach
vegetation and lack large dune systems, such that
there is an absence of the chamaephytes and forbs
characterizing the subgroups TEM-2 and TEM-4.
This last subgroup grouped together nine sites
(one in northern California and eight in southern
Oregon) with a floristic composition similar to
that of TEM-2, yet with significantly different
percentages of beach and foredune vegetation and
a lack of plants growing in deflation areas (for
instance Armeria maritima ssp. californica, Cardionema ramosissimum, Lupinus littoralis, Poa
macrantha and Polygonum paronychia are missing). This indicates the lesser extension and lower
number of habitats of the dune systems in the
TEM-4 group compared to TEM-2.
According to the succession process of the
coastal dunes of Oregon (Kumler 1963, 1969;
Wiedemann 1966), subgroup TEM-5 clustered
sites whose vegetation was closer to the last stages
of succession, comprising mature Sitka spruce
woods accompanied by Pseudotsuga menziesii,
Tsuga heterophylla and Thuja plicata. Their high
proportions of nemoral species such as Gaultheria
shallon, Polystichum munitum or Vaccinium
ovatum, are good indicators of this subgroup,
which, on the other hand, lacks the herbaceous
plants of the dune complexes typical of the
previous subgroups. Subgroup TEM-6 was the
group with the lowest number of taxa per site (6)
including nine sites in California and eight from
Oregon to British Columbia. Highest percentages
were achieved by L. mollis ssp. mollis and
L. japonicus var. maritimus, indicating that these
sites only harboured beach vegetation with no
dune systems showing the woods of P. sitchensis,
P. contorta and other psammophilous communities that characterize the previous subgroups.
The temperate zone has generally been recognized as a natural one by biogeographers,
although it has received several names: Oregonian (Dice 1943; Udvardy 1975a, b; Brown et al.
1998), Tsuga heterophylla-province (Daubenmire
1978) and Cascade (Rivas-Martı́nez et al. 1999).
The northern border of this phytogeographical
unit can be placed at the limit between temperate
and oceanic boreal climates, i.e., approximately at
5420¢ N, where Dice assigned the northern border of the Oregonian province. The southern
123
238
Plant Ecol (2007) 191:221–252
Table 3 Summary of differential and common taxa for ZB
VIII and V
Zonobiomes
VIII V
Number of sites
Number of taxa
21
110
ZB-VIII: Differential taxa
Betula papyrifera var. kenaicaBOR
Puccinellia hulteniiBOR
Senecio pseudoarnicaNAE
Equisetum sylvaticumHOL
Ligusticum scoticum ssp. hulteniiBOR
Poa eminensBOR
Stellaria humifusaHOL
Empetrum nigrumHOL
Geocaulon lividumNOA
Linnaea borealis ssp. americana NOA
Picea glaucaNOA
Rosa acicularis ssp. acicularisHOL
Shepherdia canadensisNOA
Lathyrus palustrisNOA
Lycopodium annotinumHOL
Orthilia secundaHOL
Sorbus sitchensisWES
Angelica lucidaNAE
Dendranthema arcticum ssp.
arcticumNAE
Poa macrocalyxBOR
Artemisia campestris ssp. borealisHOL
Atriplex alaskensisBOR
Salicornia maritima COS
Carex ramenskiiNAE
Epilobium ciliatum ssp.
glandulosumNOA
Parnasia palustris var. palustrisHOL
Puccinellia nutkaensisPAC
Puccinellia phryganodes ssp.
phryganodes HOL
Rhinanthus minor ssp.
groenlandicus BOR
ZB-V: Differential taxa
Gaultheria shallonPAC
Vaccinium ovatumPAC
Lonicera involucrata var.
involucrataWES
Salix hookerianaPAC
Ammophila arenaria INT
Pinus contorta var. contortaPAC
Myrica californicaPAC
Carex obnuptaPAC
Juncus lesueuriiPAC
Polystichum munitumWES
Hypochaeris radicataINT
Sarcocornia perennis* HOL
Juncus falcatusCOS
Distichlis spicataNOA
Jaumea carnosaWES
Arctostaphylos uva-ursiHOL
Anaphalis margaritaceaHOL
123
Habitat
70
213
87.0
60.9
60.9
56.5
52.2
52.2
52.2
47.8
47.8
47.8
47.8
47.8
47.8
43.5
43.5
43.5
43.5
30.4
26.1
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
CLVE
MUDF
FODU
CLVE
FODU
FODU
ESTU
CLVE
CLVE
CLVE
CLVE
CLVE
CLVE
ESTU
CLVE
CLVE
CLVE
FODU
FODU
21.7
17.4
17.4
17.4
14.3
14.3
_
_
_
_
_
_
ESTU
FODU
SALT
SALT
ESTU
ESTU
14.3 _
13.0 _
13.0 _
ESTU
MUDF
SALT
13.0 _
ESTU
_
_
_
60.0 EDFO
50.0 EDFO
42.9 WEIN
_
_
_
_
_
_
_
_
_
_
_
_
_
_
41.4
41.4
38.6
37.1
35.7
32.9
32.9
27.1
25.7
25.7
24.3
24.3
24.3
22.9
WEIN
FODU
EDFO
EDFO
WEIN
MEIN
EDFO
DRIN
SALT
MEIN
SALT
SALT
EDFO
INDE
Table 3 continued
Zonobiomes
VIII V
Number of sites
Number of taxa
21
110
70
213
_
_
_
_
_
_
_
_
_
22.9
22.9
22.9
20.0
20.0
17.1
17.1
15.7
15.7
BEAC
EDFO
INDE
CLVE
DRIN
DRIN
DRIN
WEIN
EDFO
_
_
_
_
_
_
_
_
_
_
15.7
14.3
14.3
14.3
12.9
12.9
12.9
12.9
12.9
11.4
EDFO
ESTU
MEIN
WEIN
CLVE
MEIN
FODU
SALT
WEIN
CLVE
_
_
_
_
_
_
_
11.4
11.4
11.4
11.4
10.0
8.6
7.1
CLVE
BEFO
UNDU
ESTU
BEFO
BADU
UNDU
91.3
87.0
78.3
69.6
47.8
60.9
50.0
38.6
50.0
24.3
68.6
11.4
BEFO
ESTU
WEIN
SALT
EDFO
WEIN
60.9
56.5
56.5
52.2
52.2
52.2
47.8
47.8
47.8
43.5
43.5
43.5
43.5
43.5
50.0
11.4
2.9
1.4
25.7
25.7
1.4
32.9
4.3
4.3
2.9
2.9
2.9
1.4
FODU
BEAC
FODU
CLVE
MEIN
FODU
CLVE
SALT
CLVE
CLVE
CLVE
CLVE
CLVE
CLVE
Cakile maritimaINT
Cytisus scopariusINT
Lupinus littoralisPAC
Alnus rubraWES
Tanacetum camphoratumPAC
Cardionema ramosissimumNOS
Polygonum paronychiaPAC
Veronica scutellataNOA
Pteridium aquilinum var.
pubescensWES
Maianthemum dilatatumWES
Schoenoplectus americanus NAS
Carex pansaPAC
Trifolium wormskjoldiiWES
Tsuga heterophyllaWES
Agrostis pallensWES
Vicia nigricans ssp. giganteaPAC
Cuscuta salina WES
Spiranthes romanzoffianaNOA
Pseudotsuga menziesii var.
menziesiiWES
Thuja plicataWES
Grindelia integrifoliaTEM
Poa confinisTEM
Lilaeopsis occidentalisPAC
Lathyrus littoralisPAC
Baccharis pilularis MED
Armeria maritima ssp. californicaPAC
Common taxa
Leymus mollis ssp. mollisNAE
Carex lyngbyeiHOL
Argentina egedii ssp. egediiNAE
Plantago maritima var. juncoidesHOL
Picea sitchensisPAC
Hordeum brachyantherum ssp.
brachyantherum*NOA
Lathyrus japonicus var. maritimusNAS
Honkenya peploides ssp. major*NAE
Conioselinum gmeliniiNAE
Viburnum edule*NOA
Festuca rubra ssp. rubraCOS
Achillea millefoliumHOL
Vaccinium uliginosum*HOL
Triglochin maritimumHOL
Dryopteris expansaNOA
Oplopanax horridus*NOA
Menziesia ferruginea*WES
Tiarella trifoliata*WES
Vaccinium membranaceum*NOA
Athyrium filix-femina ssp.
cyclosorumNOA
Deschampsia cespitosa ssp.
beringensisNAE
Mertensia maritima*HOL
Habitat
34.8 37.1 SALT
34.8 1.4
BEAC
Plant Ecol (2007) 191:221–252
239
Table 3 continued
Zonobiomes
VIII V
Habitat
Number of sites
Number of taxa
21
110
Calamagrostis canadensis*NOA
Chamerion angustifolium ssp.
circumvagum* HOL
Galium aparineHOL
Equisetum telmateia var. braunii*NOA
Glaux maritima*HOL
Ranunculus cymbalaria*HOL
Atriplex patula COS
Fragaria chiloensis ssp. pacificaNAS
Juncus balticusCOS
Cakile edentula ssp. edentula var.
edentula NOA
21.7 7.1
21.7 1.4
ESTU
EDFO
21.7
13.0
13.0
13.0
8.7
8.7
8.7
4.3
BEAC
FODU
SALT
ESTU
SALT
INDE
ESTU
BEAC
70
213
2.9
8.5
20.0
1.4
21.4
34.3
17.1
28.6
Scores are percentage of presence. Species abbreviations as
in Table 1. Habitat abbreviations: ALKA, alkaline soils;
BADU, backdunes; BEAC, beaches; BEFO, beaches and
foredunes; CLVE, climax vegetation of zonal soils; CLIF,
sea cliffs; COCH, coastal chaparral; DRIN, dry interdune
depressions; DUSC, climax dune scrub on older and more
inland dunes; EDFO, edaphoclimax forests on dunes;
ESTU, estuaries; FODU, foredunes; INDE, interdune
depressions; MANG, mangroves; MEIN, meadow
interdune depressions; MUDF, mud flats; SALT, salt
marshes; SUCC, Martirense coastal succulent scrub;
UNDU, unstable dune; WEIN, wet interdune depressions.
Species marked with an asterisk are temperate–
Mediterranean differential taxa (see Table 4)
limit, that is, the boundary between the ZB V and
IV has been disputed more. Howell (1957)
located the Mediterranean northern boundary at
4330¢ N. In contrast, Dice (1943) and Takhtajan
(1986) fixed the Mediterranean or Californian
coastal limits much further south, just north of the
San Francisco Bay Area (3750¢ N). There is
therefore a difference of nearly six degrees of
latitude that warrants our attention.
The floristic data support the existence of a
large transition zone between the territories
temperate and Mediterranean that was mapped
as the zonoecotone between the ZB V and IV
(Walter 1985). The transition is marked by the
presence of some Mediterranean elements in the
southern temperate subgroups TEM-4, TEM-5
and TEM-6, and in the transitional group ZEC-1,
which gathered the three northernmost sites of
California and a southern Oregon site (Tables 1
and 2). The four sites appeared to be linked by
their high proportions of S. hookeriana, which
forms dense thickets in wet interdune depressions, and by some wet and dry meadow species
(C. obnupta, J. falcatus, Tanacetum camphoratum). In both cases, we are dealing with plants
that form extended communities in the dune
complexes of ZB-V whose southern limits lie in
northwestern California.
The southern border of the ZB-V can be
established according to certain significant floristic changes in the coastal vegetation. While
rhizomatous species form continuous dune ridges
in temperate beaches, individual conical hillocks
up to 2 m high built by tap-rooted forbs (Abronia
maritima and A. latifolia) characterize the high
beach and foredune zones of ZB-IV. Barbour and
Johnson (1988) documented these hillocks along
the entire California coast, and Johnson (1977)
did the same for those in Baja California. South of
Morro Bay (3522¢ N) there are no beach or
foredune grasses except where European grass
(Ammophila arenaria) was planted. From approximately Morro Bay towards the north, Leymus
mollis ssp. mollis forms small dunes transverse to
the shoreline immediately behind the Abronia
hillocks, constituting a different ecological behaviour pattern with respect to the temperate
beaches in which L. mollis ssp. mollis forms
foredunes parallel to the shoreline, and from
which Abronia hillocks are absent.
The presence of dune forests dominated by
Sitka spruce and shore pine is an outstanding
feature of the ZB-V coastal dunes compared to
ZB-IV dunes. As occurs in the Iberian Mediterranean (Peinado et al. 1992), the backdunes of
Mediterranean California are covered by characteristic scrubs, including a large number of local
endemics (Tables 4 and 5). Trees are non-existent
along the dune transects of the ZB-IV, with the
exception of wet interdune depressions where
Myrica californica and Salix lasiolepis form characteristic tall shrubs or small trees. The first
stunted and flagged Sitka spruces and shore pines
start to appear on the cliffs just to the north of
Bodega Bay (at approximately 3830¢ N), but
there are no real dune forests until one reaches
the dune systems of Samoa-Arcata-Eureka
(4047¢ N), situated just north of Cape Mendocino in the rainiest, foggiest area of the ZB-IV
(Major 1988). The floristic composition of these
123
240
woods is by now very similar to woods of both
trees constituting the dune edaphoclimax in ZBV dunes, though the height of the dominant trees
is notably reduced.
In that northwestern corner of California, a
change in interdune depressions also occurs: Salix
lasiolepis, dominant in the wet interdune depressions of ZB-IV from Baja California northwards,
is replaced by S. hookeriana, which is to dominate
the same ecological positions as S. lasiolepsis
across the entire ZB-V until south of the Queen
Charlotte Islands, its northernmost limit
(Klinkenberg 2004).
The sea bluffs of the ZB-IV are species rich,
many being endemic or exclusive to it, forming
very characteristic vegetation (Table 4). In
the transitional humid zone of northwestern
California, Gaultheria shallon becomes incorporated in the sea bluffs, but on the ZB-V coast
cliffs and slopes directly exposed to the wind and
salt spray, they are directly colonized by coastal
climax forests of P. sitchensis.
Floristic changes in the saltmarshes also mark
the transition between ZB-IV and ZB-V. The
floristic composition of the ZB-IV salt marshes
reflects gradual latitudinal climatic variations.
Between northern Baja California and southern
Oregon, Mediterranean halophytes disappear one
at a time. Batis maritima, an element of tropical
origin, does not extend beyond Point Conception.
A little further north, the area between Point
Conception and San Luis Obispo, coinciding with
the change from semiarid to dry ecofloristic
subzones (Breckon and Barbour 1974), sees the
disappearance of Amblyopappus pusillus, Arthrocnemum subterminale, Atriplex watsonii, Monanthochloe littoralis and Salicornia bigelowii, all of
which are common in the southern saltmarshes.
Spartina foliosa reaches as far as Humboldt
County, north of Cape Mendocino. From this
point, the most drastic changes gradually take
place in the saltmarshes. Along with S. foliosa,
some of the common southern saltmarsh taxa
(Cordylanthus maritimus, Frankenia grandifolia
and Limonium californicum) start to disappear to
give way to plants common in ZB-V saltmarshes
which start to dominate: Glaux maritima, Plantago maritima var. juncoides, Deschampsia cespitosa ssp. beringensis, Puccinellia kurilensis
123
Plant Ecol (2007) 191:221–252
Table 4 Summary of differential and common taxa for ZB
IV and V
Zonobiomes
ZBIV
ZB- Habitat
V
Number of sites
Number of taxa
94
389
70
213
30.9
34.0
29.8
25.5
24.5
20.2
20.2
20.2
17.0
16.0
_
_
_
_
_
_
_
_
_
_
CLIF
SALT
BEFO
BADU
CLVE
UNDU
BADU
DUSC
BADU
BADU
16.0
16.0
14.9
14.9
13.8
_
_
_
_
_
SUCC
SUCC
CLVE
DUSC
CLVE
13.8
12.8
12.8
12.8
10.6
_
_
_
_
_
SUCC
BADU
WEIN
BADU
DUSC
10.6
9.6
_
_
DUSC
ALKA
Zonobiome IV: Differential taxa
Eriophyllum stoechadifolium*MED
Sarcocornia pacificaPAC
Carpobrotus chilensisINT
Erigeron glaucus*MED
Artemisia californica*MED
Artemisia pycnocephala*MED
Eriogonum latifolium*MED
Lotus scoparius var. scoparius*MED
Eriogonum parvifolium*MED
Corethrogyne californica var.
californica* MED
Agave shawii ssp. shawiiMED
Bergerocactus emoryiMED
Rhus integrifoliaMED
Ericameria ericoides*MED
Eriogonum fasciculatum var.
fasciculatumMED
Nassella lepida*MED
Eschscholzia californicaNOA
Salix lasiolepis*MAD
Amblyopappus pusillusMED
Encelia californica var.
californica MAD
Mirabilis californicaMED
Dudleya cultrataBAJ
Zonobiome V: Differential taxa
Carex lyngbyeiHOL
Deschampsia cespitosa ssp.
beringensis NAE
Cakile edentula ssp. edentula var.
edentula NOA
Sarcocornia perennis HOL
Arctostaphylos uva-ursiHOL
Plantago maritima var. juncoidesHOL
Cytisus scopariusINT
Lupinus littoralisPAC
Glaux maritimaHOL
Veronica scutellataNOA
Trifolium wormskjoldiiWES
Tsuga heterophyllaWES
Agrostis pallensWES
Vicia nigricans ssp. giganteaPAC
Spiranthes romanzoffianaNOA
Thuja plicataWES
Grindelia integrifoliaTEM
Poa confinisPAC
Lilaeopsis occidentalisPAC
Common taxa
Ambrosia chamissonisNAS
Cakile maritimaINT
Baccharis pilularis* MED
_
_
38.6 ESTU
37.1 SALT
_
28.6 BEAC
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
25.7
24.3
24.3
22.9
22.9
20.0
15.7
14.3
12.9
12.7
12.9
12.9
11.4
11.4
11.4
11.4
40.4
35.1
35.1
SALT
EDFO
SALT
EDFO
INDE
SALT
WEIN
WEIN
CLVE
MEIN
FODU
WEIN
CLVE
BEFO
UNDU
ESTU
4.3 BEFO
22.9 BEAC
8.6 BADU
Plant Ecol (2007) 191:221–252
241
Table 4 continued
Zonobiomes
ZB- ZB- Habitat
IV V
Number of sites
Number of taxa
94
389
70
213
Distichlis spicataNOA
Camissonia cheiranthifolia ssp.
cheiranthifolia* MED
Abronia latifolia*PAC
Achillea millefolium* HOL
Jaumea carnosaWES
Ammophila arenaria* INT
Cuscuta salina WES
Armeria maritima ssp.
californica*PAC
Rubus ursinus ssp. ursinus*WES
Calystegia soldanella*COS
Polygonum paronychia*PAC
Leymus mollis ssp. mollisNAE
Lupinus arboreus*PAC
Argentina egedii ssp. egedii *NAE
Lathyrus littoralisPAC
Pseudotsuga menziesii var.
menziesiiWES
Picea sitchensisPAC
Gaultheria shallonPAC
Vaccinium ovatumPAC
Lathyrus japonicus var.
maritimusNAS
Salix hookerianaPAC
Pinus contorta var. contortaPAC
Myrica californicaPAC
Carex obnuptaPAC
Triglochin maritimumHOL
Atriplex patula COS
Fragaria chiloensis ssp.
pacifica*NAS
Juncus lesueurii*PAC
Polystichum munitumWES
Hypochaeris radicataINT
Festuca rubra ssp. rubraCOS
Juncus falcatusCOS
Anaphalis margaritaceaHOL
Alnus rubraWES
Tanacetum camphoratumPAC
Juncus balticusCOS
Cardionema ramosissimumNAS
Pteridium aquilinum var.
pubescensWES
Maianthemum dilatatumWES
35.1 24.3 SALT
26.6 2.9 FODU
23.4
28.7
21.3
21.3
19.1
14.9
4.3
25.7
24.3
41.4
12.9
7.1
BEFO
FODU
SALT
FODU
SALT
UNDU
13.8
12.8
11.7
11.7
10.6
8.5
5.3
3.2
2.9
7.1
17.1
50.0
2.9
50.0
10.0
11.4
EDFO
DRIN
DRIN
FODU
DUSC
WEIN
BEFO
CLVE
3.2
3.2
1.1
1.1
68.6
60.0
50.0
50.0
EDFO
EDFO
EDFO
FODU
3.2
2.1
8.5
6.4
8.5
8.5
14.9
41.4
38.6
37.1
35.7
32.9
21.4
34.3
WEIN
EDFO
EDFO
WEIN
SALT
SALT
INDE
13.8
5.3
2.1
1.1
4.3
1.1
3.2
3.2
3.2
4.3
4.3
32.9
32.9
27.1
25.7
25.7
22.9
20.0
20.0
17.1
17.1
15.7
MEIN
EDFO
DRIN
MEIN
MEIN
INDE
CLVE
DRIN
ESTU
DRIN
EDFO
2.1
15.7 EDFO
See Tables 3 and 5 for further differential taxa of the two zones
(species marked with an asterisk in Table 3 are differential
taxa of ZB-V and those marked in Table 5 are differential taxa
of ZB-IV). Scores and abbreviations as in Table 2
and Triglochin maritimum. Sarcocornia pacifica,
dominating low saltmarsh zones from tropical
Baja California throughout the entire ZB-IV, is
Table 5 Summary of differential and common taxa for ZB
III and IV
Zonobiomes
ZBIII
ZBIV
Number of sites
Number of taxa
91
240
94
389
63.7
49.5
28.6
28.6
27.5
25.3
22.0
22.0
22.0
19.8
_
_
_
_
_
_
_
_
_
_
BADU
BADU
BEFO
BEAC
BEFO
UNDU
CLVE
BEAC
MANG
BEFO
19.8
19.8
19.8
19.8
_
_
_
_
CLVE
MANG
MANG
UNDU
18.7
_
BADU
18.7
17.6
17.6
16.5
15.4
15.4
15.4
14.3
13.2
13.2
13.2
13.2
12.1
12.1
9.9
9.9
9.9
9.9
8.8
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
CLVE
UNDU
UNDU
UNDU
UNDU
BEAC
BEFO
ALKA
CLVE
BEFO
UNDU
CLVE
CLVE
CLVE
BADU
CLVE
CLVE
CLVE
BEAC
8.8
7.7
7.7
_
_
_
BEFO
BADU
ALKA
7.7
7.7
6.6
6.6
6.6
6.6
6.6
6.6
_
_
_
_
_
_
_
_
CLIF
BEAC
ALKA
ALKA
ALKA
BEFO
UNDU
CLIF
Zonobiome III: Differential taxa
Cenchrus palmeri SON
Maytenus phyllantoides NEO
Jouvea pilosa NEO
Sporobolus virginicus NEO
Euphorbia leucophyllaSON
Proboscidea althaefolia SON
Cyrtocarpa edulis BAJ
Ipomoea pes-caprae NEO
Rhizophora mangle NEO
Oenothera drummondii var.
thalassaphila BAJ
Fouquieria diguetii SON
Avicennia germinans NEO
Laguncularia racemosa AAT
Phaseolus acutifolius var.
latifoliusNEO
Lycium fremontii var.
congestum SON
Opuntia cholla BAJ
Encelia ventorum BAJ
Froelichia interrupta NEO
Dalea divaricata ssp. anthonyi BAJ
Asclepias subulata SON
Atriplex magdalenae BAJ
Porophyllum maritimum BAJ
Jatropha cinerea NEO
Antigonon leptopus SON
Portulaca pilosa NEO
Euphorbia micromera NEO
Condaliopsis rigida BAJ
Jatropha cuneata SON
Bursera microphylla SON
Chaenactis lacera BAJ
Pachycereus pringlei SON
Jatropha cordata BAJ
Castela peninsularis BAJ
Drymaria holosteoides var.
crassifolia BAJ
Physalis glabra BAJ
Achyronychia cooperi SON
Encelia farinosa var.
phenocodonta SON
Sphaeralcea fulva BAJ
Trianthema portulacastrum PAN
Atriplex polycarpa NOA
Dyssodia anthemidifolia BAJ
Perityle emoryiMAD
Coulterella capitata BAJ
Dalea tinctoria var. tinctoria BAJ
Hofmeisteria fasciculata var.
fasciculata BAJ
Habitat
123
242
Plant Ecol (2007) 191:221–252
Table 5 continued
Table 5 continued
Zonobiomes
ZBIII
ZBIV
Number of sites
Number of taxa
91
240
94
389
Triteleiopsis palmeri
SON
Common taxa
Allenrolfea occidentalis * MAD
Abronia maritima * MAD
Frankenia palmeri * MAD
Batis maritima * NAS
Atriplex julacea * BAJ
Monanthochloe littoralis NOA
Camissonia crassifolia BAJ
Lycium californicum * MAD
Euphorbia misera * MAD
Arthrocnemum subterminale * MAD
Sarcocornia pacificaPAC
Lycium brevipes * MAD
Suaeda taxifolia * MAD
Croton californicus MAD
Stenocereus gummosus SON
Mesembryanthemum
crystallinum * INT
Atriplex canescens ssp.
canescens NOA
Suaeda moquinii NOA
Lycium andersonii MAD
Spartina foliosa * PAC
Abronia umbellata MAD
Atriplex barclayana ssp.
barclayana SON
Suaeda esteroa * MED
Frankenia salina * NAS
Ambrosia dumosa SON
Sarcostemma arenarium BAJ
Cryptantha maritima var.
maritima MAD
Stillingia linearifolia MAD
Atriplex leucophylla * MED
Distichlis spicataNOA
Helianthus niveus ssp. niveus MAD
Isocoma menziesii var.
vernonioides MAD
Limonium californicum MED
Dudleya cultrataBAJ
Mirabilis californica MED
Salicornia bigelovii NAS
Camissonia cheiranthifolia ssp.
suffruticosa MED
Cuscuta salina WES
Echinocereus maritimus BAJ
Lepidium nitidum MAD
Rhus integrifoliaMED
Ribes speciosum MED
Rosa minutifolia BAJ
123
6.6
Habitat
_
ALKA
50.5
35.2
33.0
31.9
29.7
27.5
22.0
18.7
18.7
18.7
18.7
17.6
16.5
16.5
15.4
15.4
1.1
16.0
6.4
10.6
9.6
14.9
4.3
14.9
16.0
12.8
34.0
14.9
4.3
6.4
11.7
16.0
ALKA
BEFO
ALKA
SALT
ALKA
SALT
UNDU
ALKA
ALKA
SALT
SALT
UNDU
SALT
UNDU
SUCC
BADU
14.3
8.5
UNDU
14.3
12.1
12.1
9.9
8.8
4.3
5.3
27.7
9.6
1.1
SALT
BADU
SALT
BADU
BEFO
6.6
5.5
5.5
5.5
5.5
13.8
26.6
1.1
2.1
3.2
SALT
SALT
BADU
UNDU
UNDU
4.4
4.4
4.4
4.4
3.3
1.1
13.8
24.3
12.8
8.5
BADU
BEFO
SALT
UNDU
BADU
3.3
2.2
2.2
2.2
1.1
19.1
9.6
10.6
9.6
7.4
SALT
ALKA
ALKA
SALT
BEFO
1.1
1.1
1.1
1.1
1.1
1.1
19.1
10.6
4.3
14.9
6.4
7.4
SALT
BADU
BADU
CLVE
CLVE
CLVE
Zonobiomes
ZBIII
ZBIV
Number of sites
Number of taxa
91
240
94
389
Pentagramma triangularis var.
viscosa WES
Malosma laurina MED
1.1
5.3
CLVE
1.1
8.5
CLVE
Isomeris arborea
MAD
1.1
3.2
Habitat
CLVE
Further differential taxa of the two ZB can be found in
Table 4 (species marked with an asterisk in Table 4 are
ZB-IV differential taxa). Scores and abbreviations as in
Table 3
replaced here by its vicariant S. perennis, which
occupies intertidal zones from Oregon to British
Columbia. These major changes in saltmarshes
are sustained by climatic changes that modify the
water temperature and salinity (Macdonald and
Barbour 1974; Macdonald 1988).
Transition is more gradual in coastal forests
due to the moderating effect of fog. North of
Cape Mendocino, redwoods belonging to the
association Oxalis oregana–Sequoia sempervirens
settle on northern or ocean-exposed slopes where
the fog effect is ecologically important, and are
replaced on sunny or leeward slopes by the more
drought-tolerant association Arbutus menziesi–
Lithocarpus densiflorus dominated by sclerophyllous evergreen trees (Peinado et al. 1997a, b).
Given that the northern limit of S. sempervirens
lies in the Chetco River Valley (4205¢ N), we
established the Mediterranean phytogeographical
border at this point of southern Oregon (Peinado
et al. 1997b). This boundary is supported by the
changes in vegetation of beaches and unstable
dunes. The last dune system south of the Chetco
River is that of Point St. George (Kellog Beach,
4152¢ N), while the first significant dune system
north of this river appears in Bullard Beach State
Park (4308¢ N). The coastal strip between both
sites sustains an extremely oceanic Sitka spruce
forest of the association Polystichum munitum–
Picea sitchensis, but only a few km inland in Point
St. George, the regional climax is the sclerophyllic
association Arbutus menziesii–Lithocarpus densiflorus, whereas at Bullard Beach, the regional
climax forest corresponds to the temperate forests
Plant Ecol (2007) 191:221–252
of the ZB-V association Thuja plicata–Tsuga
heterophylla (Peinado et al. l.c.).
Hence, if we interpret the dune forests of Sitka
spruce and shore pine to be characteristic of
temperate coastal dunes, then the southern border
of the ZB-V would have to be taken to the Samoa
dunes (4047¢ N). If besides this criterion, we use
floristic changes in the vegetation of beaches,
dunes, sea-facing cliffs, saltmarshes and climax
forests as the discriminating factors, then the
floristic boundary between ZB-V and ZB-IV
would have to be drawn further north, up to the
Chetco River (4205¢ N), coinciding with the
northern limit of the redwoods. Stebbins and Major
(1965) placed the coastal limit of the Californian
Floristic Province at the mouth of the Rogue River
in Oregon, approximately at 4230¢ N, a border
also established by Raven (1988), Thorne (1993)
and Rivas-Martı́nez et al. (1999). Our floristic
results support this last boundary.
In summary, with the exception of the northern California sites, which may be considered as
transitional temperate–Mediterranean but with a
well-differentiated flora (Table 1: Northern
Mediterranean group), the sites included in the
ZB-V group have a homogenous floristic base
that allows the inference of ecological or successional differences but not phytogeographical.
All the temperate climate zone is included in the
ZB-V, extending approximately from the Chetco
River, Oregon, to Dixon Entrance, British
Columbia.
From Bocana de El Rosario, Baja California
(site 91), to Talawa Lake, California (site 186),
there are 94 sites linked to Mediterranean meteorological stations, most of which (73; 77.7%)
gathered together in the ZB-IV cluster, whereas
ten sites were included within ZEC-2. The number of Mediterranean endemics recorded in the
narrow band of coastal vegetation of the ZB-IV
group amounts to 40.8% and reaches 50% in
MED-3 (Table 2).
Group ZB-IV was divided into seven subgroups. All these subgroups, but MED-1, shared
the same geographical distribution of some of
their taxa. As occurred in ZB-V, most sites with
salt marshes were grouped together in subgroup
MED-1. Subgroups MED-2, MED-3 and MED-4,
243
spanning the humid zone of northwestern California, show a mainly northern distribution of
flora including both exclusive taxa (Table 1:
Northern Mediterranean group) and taxa shared
with the temperate zone (Table 1: Temperate–
northern Mediterranean group). This humid area
of the northern portion of California, with its high
rainfall and with fogs compensating summer
droughts, means that many plants of temperate
optimum descend southwards down the California coast along a narrow coastal strip that barely
penetrates 30-km inland (Zinke 1988). McLaughlin (1989) mapped the high presence of temperate
taxa belonging to his Vancouverian element in
northwestern California, with a steady decrease in
their percentages southwards until their disappearance close to Monterey Bay.
Subgroup MED-2 included 19 sites in northern
California, between 37 and 4150¢ N, i.e., from
north Monterey to the California–Oregon border.
The subgroup bears clear floristic links with
subgroup MED-3, but this last group lacks beach
and saltmarsh taxa (lack of Abronia latifolia,
Ammophila arenaria, L. mollis ssp. mollis,
S. pacifica and Spartina foliosa) and dune scrub
plants predominate: Artemisia californica, A.
pycnocephala, Baccharis pilularis, Corethrogyne
filaginifolia var. californica, Eriogonum parvifolium and Eriophyllum stoechadifolium. The sites in
subgroup MED-3 mostly corresponded to the
dune systems of Monterey Bay.
Subgroup MED-4 contained five sites in which
Abronia maritima and A. latifolia coexisted, an
event only occurring in some of the central
Californian sites. These sites lacked dune scrub
and foredune plants, yet sustained high proportions of Camissonia cheiranthifolia ssp. cheiranthifolia, Ambrosia chamissonis and Cakile
maritima, indicating they were beach sites. Subgroup MED-5 grouped eight sites around Point
Conception, where we find the only well-preserved dune systems of southern California:
Guadalupe, Nipomo, Pismo Beach and Oso
Flaco. The high number of species per site reflects
the diversity of these habitats, presenting willow
thickets (Myrica californica, Salix lasiolepis),
extensive dune scrubs (Eriogonum parvifolium,
Ericameria ericoides, C. filaginifolia var. califor-
123
244
nica, Lupinus chamissonis and the local endemics
Erigeron blochmaniae, Monardella crispa and
Senecio blochmaniae), and dry meadows of Juncus leuseurii and Carex pansa. Conicosia pungioniformis, an introduced Aizoaceae, makes its
only appearance in North America in these
dunes. In subgroup MED-5, the taxa of northern
Mediterranean distribution reach their southern
limits and coexist for the first time with the taxa of
the Southern Mediterranean group (Table 1).
Subgroups MED-6 and MED-7 gather together
the relevés taken in southern California and
northwestern Baja California. Both subgroups
are characterized by an abundance of southern
elements and plants comprising the coastal
succulent scrub (Table 1: Southern Mediterranean and Southern Mediterranean–Tropical
groups). The proportions of these last plants are
highest in MED-7, which groups the southern
sites, from the Tijuana basin to Punta Colonet.
Subgroup MED-6 included relevés that were
somewhat more northern; the floristic difference
between the two subgroups being the presence in
MED-6 of some saltmarshes and of the most
southern populations of Ammophila arenaria and
Baccharis pilularis, absent from the Baja California coast. Unlike the other MED subgroups, in
both these southern subgroups we find genera of
tropical origin: Agave, Batis, Croton, Justicia,
Myrtillocactus and Stenocereus. These subgroups
also show a greater presence of Madrean and
Mediterranean endemic taxa. Besides, in these
southern subgroups Mediterranean–tropical taxa
undergo a distribution increase and are especially
dominant in the transitional subgroup ZEC-2.
Subgroup ZEC-2 included 14 sites at 29 to
3030¢ N, in the transition area between the
Mediterranean and tropical zones. The southern
boundaries of Van Dyke’s (1919) California
faunal zone, Dice’s (1943) Californian biotic
province and Howell’s (1957) California flora
province appear around 3030¢ N, and the flora
and vegetation of this area have long been
considered ‘‘transitional’’ (Shreve 1936; Shreve
and Wiggins 1964; Peinado et al. 1995a). Breckon
and Barbour (1974) reported that the Baja
California beach vegetation underwent a floristic
shift close to 3030¢ N, while Johnson (1977)
described this zone as one showing the striking
123
Plant Ecol (2007) 191:221–252
replacement of herbaceous dune species between
the ‘‘northern’’ (or Mediterranean) and ‘‘central’’
(or tropical) regions.
The flora in the transitional cluster ZEC-2
shows features that are intermediate between
those of the climatic zones Mediterranean and
tropical (Table 1). In this subgroup, we can
observe a percentage decrease in coastal succulent scrub elements, a reduction in the number of
Madrean and Mediterranean endemic taxa, a high
proportion of local endemics such as Dudleya
cultrata and Astragalus anemophilus, and the
presence of dune scrubs of Euphorbia misera,
Helianthus niveus, Lycium brevipes and L. californicum. The subgroup also presents elements of
tropical distribution such as Atriplex julacea,
Camissonia crassifolia or Pachycereus schottii,
adding to those observed in the southernmost
Mediterranean subgroups. The climatic characteristics of this zonoecotone are Mediterranean
(Müller 1982; Delgadillo 1995), and the proportion of taxa related to ZB-IV is much higher than
that related to ZB-III (Table 2). Peinado et al.
(1995a) examined the flora of this territory and
included it in the climatically Mediterranean
Martirense province (Californian region). The
coastal flora supports this conclusion and the sites
of the ZEC-2 group found north of Punta San
Carlos (2937¢ N) should be considered to be
within the ZB-IV.
Ninety sites were initially linked to tropical
areas. In the cluster analysis, 86 clustered
together into ZB-III, and four into subgroup
ZEC-2. The ZB-III subgroups are characterized
at the species level by their high percentages of
Madrean, Sonoran, Baja Californian and
Neotropical phytogeographic elements (Table 2).
Greatest concentrations of tropical flora occur on
the coast of Baja California, a peninsula that
separated from the continent during the Late
Tertiary, around 3.6 Ma ago (Minch et al. 2003),
a time of intense specialization of its flora,
including 751 endemic taxa, of which 22 are
endemic genera (Delgadillo 1995).
Table 1 reveals a clear separation between
subgroup TRO-1 and the remaining three tropical
subgroups. In TRO-1 there is a predominance of
taxa of Southern Mediterranean–Tropical distribution, many of which are missing or are very
Plant Ecol (2007) 191:221–252
scarce in subgroups TRO-2, TRO-3 and TRO-4.
In contrast, these last three subgroups are
characterized by a group of taxa showing Southern Tropical distribution. Table 2 also shows clear
differences among the phytogeographical
elements that make up these subgroups.
The TRO-1 subgroup contained the most
northern sites of the tropical climate zone,
reflected both in the high number of plants of
the group Southern Mediterranean–Tropical and
the lack of taxa showing a Southern tropical
distribution (Table 1: Thermotropical taxa).
These sites are located north of Punta Abreojos,
in the southern part of the El Vizcaı́no Biosphere
Reserve. In the warm tropical zone south of
Punta Abreojos, foredunes are built by the
tropical grasses Jouvea pilosa and Sporobolus
virginicus, together with the pantropical species
Ipomoea pes-caprae, I. stolonifera, Scaevola plumieri and Trianthema portulacastrum, with a floristic composition that we have observed
southwards at least down to Jalisco and the
Nayarit coast of continental Mexico. Punta
Abreojos is a zone where climate changes from
a Bwk- to a Bwh type due to the increasing mean
annual temperature, which is accompanied by a
change in eco-floristic zones, whereby the warmer
south arid zone gives way to the northern arid
zone (Breckon and Barbour 1974). The coastal
boundary between the cooler Vizcaı́no and the
warmer Magdalenan phytogeographical sectors of
the Baja Californian province occurs approximately 20¢ south of Punta Abreojos, at Bahı́a de
San Juanico, where Shreve and Wiggins (1964)
located the transition between the Vizcaı́no and
Magdalenan subdivisions of the Sonoran Desert.
The Vizcaı́no plains (TRO-1 sites) show different climatic characteristics from other arid
zones of Baja California (Turner and Brown 1982;
Anon. 1995) such that they form a clearly defined
floristic, biogeographical unit (Shreve and
Wiggins 1964; Wiggins 1969; Turner and Brown
1982; Peinado et al. 1994b; Delgadillo 1995). The
plant communities of this unit are highly characteristic and inexistent outside the area, such as the
communities of the Saltbush Series that thrive on
the extensive coastal flats, very rich in Baja
California endemics (Turner and Brown 1982),
and the shrublands of the aeolian dunes. The
245
barchan-shaped dunes of El Vizcaı́no are unique
to North America (Wiggins 1980) owing both to
their geomorphological features (Inman et al.
1966) and the richness of their flora. Thus, the
dune systems of El Vizcaı́no and their alkaline
postdune plains harbour 183 plants endemic to
Baja California, 89 of which do not exist elsewhere in the peninsula (Peinado et al. 2005). The
taxa differentiating subgroup TRO-1 with respect
to the subgroups TRO-3 and TRO-4 are characteristic elements of the Baja Californian floristic
province, in which El Vizcaı́no forms a differentiated phytogeographical sector (Peinado et al.
1994b; Delgadillo 1995). Many Baja Californian
and Vizcaı́no endemics characterize TRO-1: Atriplex julacea, Camissonia crassifolia, Chaenactis
lacera, Dyssodia anthemidifolia, Encelia laciniata,
E. ventorum and Sphaeralcea fulva, among others.
Sites with mangroves were grouped into subgroup TRO-2, characterized by high percentages
of Avicennia germinans, Laguncularia racemosa,
Maytenus phyllanthoides and Rhizophora mangle.
From the southern tip of the peninsula, tropical
mangroves spread northward to Punta Abreojos
on the Pacific coast and to Bahı́a de los Ángeles on
the warmer Gulf coast (Peinado et al. 1995c).
Mangroves thrive only in the thermotropical bioclimatic belt of Baja California (Peinado et al.
1994a, 1995c, 1997a). This bioclimatic belt appears
both in the Baja Californian and Sanlucan phytogeographical provinces (Peinado et al. 1994b).
Many plants whose distribution in North America
is restricted to both phytogeographical provinces
characterize the thermotropical subgroups TRO-2,
TRO-3 and TRO-4, including most of the genera
and species with tropical relations (Table 2). Subgroups TRO-3 and TRO-4 showed the least Madrean and Mediterranean elements, indicating their
more distant relationship with the northern flora.
In contrast, the percentage of taxa with tropical
relationships (Sonoran and Tropical elements) was
the highest of all the groups (Table 2). In these two
subgroups, the number of species endemic to Baja
California reached the greatest proportions, suggesting their isolation with respect to the other
tropical subgroups. The southernmost subgroups
TRO-3 and TRO-4 show a set of taxa (Table 1:
Sanlucan taxa) that are endemic to the Sanlucan
province or whose distribution area in Baja Cali-
123
246
Plant Ecol (2007) 191:221–252
fornia is restricted to this province. Most of these
taxa belong to the Cape Region floristic group
identified by A. F. Johnson in her floristic analysis
of the Baja California dunes (Johnson 1977).
(5)
Conclusions
(1)
(2)
(3)
(4)
There are four ZB along the coast of the
North American Pacific: ZB-VIII or Boreal,
ZB-V or Temperate, ZB-IV or Mediterranean, and ZB-III or Tropical, which show a
coastal flora and azonal vegetation characteristic to each zonobiome; the latitudinal
limits of the azonal vegetation practically
coinciding with those already established for
the zonal vegetation.
The northern ZB VIII and V present high
percentages of broadly distributed elements.
The macroclimates that characterize these
ZB are widespread at the continental and
intercontinental level, allowing the intense
exchange of species. Accordingly, they show
very low proportions of local endemics and
exclusive species.
ZB-VIII has the highest percentage of
widely distributed elements (Cosmopolitan,
Holarctic, North American and Western
North American), which together represent
63.6% of the species. It is also the zonobiome with the greatest proportions of genera
and species showing a North American–
Eastern Asian distribution. Picea glauca
forests and mud flats are exclusive to this
zonobiome.
The vegetation of ZB-V shows high diversity
mainly owing to the complexity of its dune
systems that sustain a large variety of communities linked to successional processes that
culminate in climax dune forests dominated
by Pinus contorta var. contorta and Picea
sitchensis, which are exclusive to this zonobiome. Coastal saltmarshes bear some floristic
resemblance to the Mediterranean ones yet
differ intensely because of the dominance of
taxa showing a northern temperate–boreal
distribution, such as Carex lyngbyei, Plantago
123
(6)
(7)
(8)
maritima var. juncoides, Sarcocornia perennis
or Triglochin maritimum.
Between ZB-V and ZB-IV there is a clear
zonoecotone, and the limits of the two ZB
have been ascribed different latitudes. Our
analysis of the flora and coastal vegetation
locate this boundary in the surroundings of
the Chetco River basin, at 4205¢ N, coinciding with substantial changes in the coastal
flora and azonal vegetation.
The floristically richest zonobiome in terms
of their high number of endemic taxa is
ZB-IV. Only 21.5% of the species of this
zonobiome belong to the elements of wide
distribution that predominate in the boreal
and temperate ZB.
ZB-IV includes a high variety of exclusive
azonal communities, among which we may
find highly diversified dune scrubs rich in
endemic species. Hillocks dominated by taprooted species (Abronia latifolia from central
California northwards, and A. maritima,
from central California to Baja California)
are characteristic of Mediterranean beaches.
ZB-IV saltmarshes exhibit a characteristic
zonation, and although they share some taxa
with the temperate saltmarshes, they present
significant floristic differences.
The flora of Baja California, except in its
Mediterranean northwestern corner, belongs to ZB-III, and is characterized by a
high number of taxa related to tropical flora,
especially to those with which links with
South America may be established. Only
3.9% of the species of the tropical zone
belong to elements of wide distribution. In
this zonobiome, species of Holarctic and
cosmopolitan distribution are totally lacking. In contrast, taxa related to the tropical
element, Sonoran endemics and Baja
Californian endemics represent 69.3% of
species.
Acknowledgments This study was made possible by an
agreement between the Universidad de Alcalá and
Universidad Autónoma de Baja California, and
supported by grants from the Dirección General de
Universidades (PR2004-0176), Agencia Española de
Plant Ecol (2007) 191:221–252
Cooperación Internacional (A/1628/04), and Fundación
RAYET. Part of this research was carried out during a stay
at the Facultad de Ciencias de la Universidad Autónoma
de Baja California en Ensenada. The authors thank the
faculty head, Dr. Nahara Ayala, for supporting our
fieldwork trips. We also thank Ana Burton for help with
the English translation.
Appendix 1: Sampled sites
Baja California Sur: 1. Migriño (2302¢ N–
11006¢ W); 2. Bahı́a Tortuga (2306¢ N–
10932¢ W); 3. La Fortuna (2308¢ N–10930¢ W);
4. Santa Elena (2309¢ N–10929¢ W); 5. Punta
Paredones (2310¢ N–10928¢ W); 6. Boca de la
Vinorama (2313¢ N–10927¢ W); 7. Plutarco Elı́as
Calles (2314¢ N–11009¢ W); 8. Boca de la Ardilla
(2315¢ N–10926¢ W); 9. Boca del Salado
(2317¢ N–10926¢ W); 10. Playa Los Cerritos
(2318¢ N–11009¢ W);
11.
El
Pescadero
(2319¢ N–11010¢ W); 12. Playa San Pedrito, Bahı́a de Todos Santos (2321¢ N–11011¢ W); 13.
Bahı́a de los Frailes (2322¢ N–10925¢ W); 14.
Parque Nacional Cabo Pulmo (2326¢ N–
10925¢ W); 15. Cabo Pulmo (2327¢ N–
10926¢ W); 16. Las Playitas, Todos Santos
(2329¢ N–11016¢ W); 17. Punta Las Arenas lighthouse (2333¢ N–10929¢ W); 18. Punta Colorada
(2333¢ N–10930¢ W); 19. La Ribera (2335¢ N–
10932¢ W); 20. Mocorito, Bahı́a las Palmas
(2336¢ N–10934¢ W); 21. Ejido La Conquista
(2356¢ N–11051¢ W); 22. Las Arenas (2359¢ N–
10949¢ W); 23. El Teso, Bahı́a la Ventana
(2404¢ N–10956¢ W);
24.
Punta
Conejo
(2404¢ N–11101W); 25. El Sargento (2405¢ N–
11000¢ W); 26. Bahı́a Ventana (2408¢ N–
10958¢ W); 27. El Cajete (2414¢ N–11036¢ W);
28. between La Paz and Pichilingüe (2415¢–
11018¢ W); 29. Bahı́a Pichilingue (2417¢–
11020¢ W); 30. Bahı́a Balandra (2419¢ N–
11019¢ W); 31. El Camarón (2420¢ N–
11039¢ W); 32. Playa El Tecolote (2420¢ N–
11018¢ W); 33. Rancho Piedras Coloradas
(2421¢ N–11040¢ W); 34. San Juan de la Costa
(2422¢ N–11041¢ W); 35. El Junco (2424¢ N–
11041¢ W); 36. Puerto Chale (2425¢ N–
1132¢ W); 37. Punta Tarabillas (2426¢ N–
11041¢ W); 38. Puerto Cancun (2435¢ N–
11141¢ W); 39. Las Ánimas (2437¢ N–
247
11044¢ W); 40. Punta Coyote (2441¢ N–
11043¢ W); 41. Puerto San Carlos (2447¢ N–
11207¢ W); 42. Isla Magdalena (2505¢ N–
11209¢ W); 43. Isla Magdalena (2512¢ N–
11207¢ W); 44. Puerto Abelardo López Mateos
(2513¢ N–11207¢ W); 45. Isla de Santo Domingo
(2517¢ N–11207¢ W); 46. El Paraı́so (2535¢ N–
11203¢ W); 47. Estero el Gato (2539¢ N–
11203¢ W); 48. La Poza Grande (2541¢ N–
11204¢ W); 49. Laguna Puerto Escondido
(2549¢ N–11117¢ W); 50. Loreto (2600¢ N–
11121¢ W); 51. San Juanico (2615¢ N–
11227¢ W); 52. El Dátil (2626¢ N–11247¢ W);
53. Bahı́a Concepción (2633¢ N–11143¢ W); 54.
Bahı́a Concepción (2634¢ N–11140¢ W); 55. Bahı́a Concepción (2643¢ N–11153¢ W); 56. Bahı́a de
Ballenas (2644¢ N–11332¢ W); 57. Playa del
Burro (2644¢ N–11153¢ W); 58. Playa Santispac
(2646¢ N–11153¢ W); 59. between Punta Abreojos and El Coyote (2647¢ N–11330¢ W); 60. Playa
los Naranjos (2647¢ N–11151¢ W); 61. La Bocana, El Vizcaı́no Biosphere Reserve (2649¢ N–
11343¢ W); 62. Mulegé dunes (2652¢ N–
11155¢ W); 63. Bahı́a de San Hipólito (2652¢ N–
11345¢ W); 64. El Vizcaı́no Biosphere Reserve
(2656¢ N–11348¢ W); 65. La Serenidad, Mulegé
(2656¢ N–11202¢ W); 66. Punta Prieta (2701¢ N–
11401¢ W); 67. Punta Chivato (2704¢ N–111–
57¢ W); 68. Bahı́a Abreojos road (2707¢ N–
11407¢ W); 69. Playa Los Médanos (2708¢ N–
11412¢ W); 70. Bahı́a Asunción (2709¢ N–
11418¢ W); 71. Rancho El Paraı́so (2711¢ N–
11317¢ W); 72. Barra de San Bruno (2712¢ N–
11211¢ W); 73. Bahı́a Tortugas (2741¢ N–
11453¢ W); 74. Punta Caballo de Piedra, Malarrimo (2747¢ N–11442¢ W); 75. Estero Laguna Ojo
de Liebre (2747¢ N–11405¢ W); 76. Malarrimo
(2746¢ N–11434¢ W); 77. El Chevo (2749¢ N–
11451¢ W); 78. Laguna Ojo de Liebre (2752¢ N–
11359¢ W); 79. Guerrero Negro (2757¢ N–
11404¢ W); 80. Guerrero Negro (2802¢ N–
11401¢ W).
Baja California Norte: 81. Jesús y Marı́a
(2806¢ N–11400¢ W); 82. La Bocana de Jesús y
Marı́a (2813¢ N–11403,W); 83. Laguna Manuela
(2815¢ N–11404¢ W); 84. Miller’s Landing
(2829¢ N–11403¢ W); 85. Santa Rosalillita
(2841¢ N–11414¢ W); 86. Bahı́a de los Ángeles
(2855¢ N–11333¢ W);
87.
Punta
Canoas
123
248
(2926¢ N–11512¢ W); 88. Puerto Catarina
(2931¢ N–11515¢ W); 89. Punta San Carlos
(2937¢ N–11531¢ W); 90. Punta Baja (2958¢ N–
11547¢ W); 91. Bocana del Rosario (3002¢ N–
11547¢ W); 92. El Campito (3009¢ N–11548¢ W);
93. Playa El Tranquilo (3016¢ N–11548¢ W); 94.
El Socorrito (3019¢ N–11549¢ W); 95. El Pabellón, bahı́a de Santa Marı́a (3022¢ N–11551¢ W);
96. San Quintı́n (3024¢ N–11554¢ W); 97. Los
Volcanes (3027¢ N–11602¢ W); 98. El Papolote
(3027¢ N–11547¢ W); 99. La Chorera (3028¢ N–
11602¢ W); 100. La Pedrera (3029¢ N–
11603¢ W); 101. Laguna Figueroa (3041¢ N–
11601¢ W); 102. Bahı́a Camalú (3047¢ N–
11605¢ W); 103. San Felipe (3057¢ N–
11447¢ W); 104. Bahı́a Colonet (3058¢–
11617¢ W); 105. San Antonio del Mar (3107¢ N–
11619¢ W); 106. Bocana Eréndira (3116¢ N–
11623¢ W); 107. Puerto San Isidro (3117¢ N–
11624¢ W); 108. Punta Cabras (3119¢ N–
11627¢ W); 109. La Bocana de Santo Tomás
(3133¢ N–11641¢ W);
110.
Punta
Banda
(3143¢ N–11643¢ W); 111. La Salina, Ensenada
(3149¢ N–11636¢ W); 112. Bahı́a de Todos los
Santos (3152¢ N–11637¢ W); 113. Playa Saldamando (3156¢ N–11646¢ W); 114. Salsipuedes
(3158¢ N–11647¢ W); 115. La Salina, sur de
Tijuana (3203¢ N–11654¢ W); 116. Plaza del
Mar (3207¢ N–11655¢ W); 117. El Médano
(3213¢ N–11654¢ W);
118.
El
Rosarito
(3217¢ N–11703¢ W).
California: 119. Tijuana Estuary (3234¢ N–
11708¢ W); 120. Imperial Beach (3236¢ N–
11709¢ W); 121. Mission Bay (3246¢ N–
11714¢ W); 122. Torrey Pines State Reserve
(3255¢ N–11716¢ W);
123.
Newport
Bay
(3338¢–11754¢ W); 124. Point Mugu (3405¢ N–
11903¢ W); 125. Santa Monica Bay (3405¢ N–
11840¢ W); 126. Oxnard Beach (3408¢ N–
11911¢ W); 127. Port Hueneme Beach
(3409¢ N–11911¢ W); 128. Carpinteria State
Beach (3424¢ N–11930¢ W); 129. Gaviota State
Beach (3428¢ N–12011¢ W); 130. Jalama Beach,
Point Conception (3432¢ N–12037¢ W); 131.
Rancho Guadalupe Dune Preserve (3457¢ N–
12039¢ W); 132. Pismo Dunes Preserve, Pismo
Beach (3500¢ N–12035¢ W); 133. Oso Flaco
Lake (3502¢ N–12037¢ W); 134. Ocean Dunes,
Pismo Beach (3507¢ N–12038¢ W); 135. Oso
123
Plant Ecol (2007) 191:221–252
Valley Sand Spit (3519¢ N–12052¢ W); 136.
Morro Bay (3522¢ N–12051¢ W); 137. San Simeon (3535¢ N–12107¢ W); 138. Piedras Blancas
(3540¢ N–12115¢ W); 139. Garrapata Creek
(3625¢ N–15155¢ W); 140. Seal Point, Monterey
Bay (3635¢ N–121–58W); 141. Scenic Drive,
Monterey Bay (3636¢ N–12157¢ W); 142. Bay
lagoon, Monterey Bay (3636¢ N–12151¢ W);
143. Spanish Drive, Monterey Bay (3636¢ N–
121–59W); 144. Asilomar State Beach (3637¢ N–
12156¢ W); 145. Seaside Beach, Sand City
(3637¢ N–12151¢ W); 146. Marina State Beach
(3642¢ N–12148¢ W); 147. Salinas River State
Beach (3647¢ N–12148¢ W); 148. Moss Landing
State Beach (3649¢ N–12147¢ W); 149. Elkorn
Slough National Estuarine Preserve (3649¢ N–
12143¢ W); 150. Año Nuevo State Reserve
(3707¢ N–12218¢ W);
151.
Gazos
Creek
(3710¢ N–12222¢ W);
152.
Bean
Hollow
(3713¢ N–12224¢ W); 153. Pescadero Beach
(3716¢–12225¢ W); 154. Pomponio State Beach
(3718¢ N–12221¢ W); 155. Dunes Beach, Half
Moon Bay (3729¢ N–12227¢ W); 156. San Francisco Bay (3732¢ N–12212¢ W); 157. Moss Beach
(3732¢ N–12230¢ W);
158.
Muir
Beach
(3751¢ N–12234¢ W); 159. Stinson Beach
(3754¢ N–12239¢ W); 160. Lighthouse bluffs,
Point Reyes National Seashore (3759¢ N–
12300¢ W); 161. Drake Beach, Point Reyes
National Seashore (3801¢ N–12257¢ W); 162.
South Beach, Point Reyes National Seashore
(3803¢ N–12259¢ W); 163. North Beach, Point
Reyes National Seashore (3804¢ N–12258¢ W);
164. Schooner Bay, Point Reyes National Seashore (3806¢ N–12254¢ W); 165. Kehoe Beach,
Point Reyes National Seashore (3809¢ N–
12256¢ W); 166. San Pablo Wildlife National
Refuge, San Pablo Bay (3810¢ N–12230¢ W);
167. McClure Beach, Point Reyes National Seashore (3811¢ N–12257¢ W); 168. Dillon Beach
(3815¢ N–12258¢ W);
169.
Bodega
Bay
(3820¢ N–12304,W);
170.
Miwok
Beach
(3821¢ N–12304¢ W); 171. Goat Rock State
Beach (3827¢ N–12307¢ W); 172. Dump Beach,
Point Arena State Park (3835¢ N–12320¢ W);
173. Manchester Beach State Park (3858¢ N–
12342¢ W); 174. Ten Mile River (3933¢ N–
12346¢ W); 175. Mackerringer State Park
(3929¢ N–12347¢ W); 176. Cape Mendocino
Plant Ecol (2007) 191:221–252
(4020¢ N–12420¢ W); 177. Bear River, Capetown (4029¢ N–12418¢ W); 178. Samoa dunes,
Eureka (4047¢ N–12412¢ W); 179. Arcata Bottoms (4059¢ N–12406¢ W); 180. Patrick Point
State Park (4108¢ N–12408¢ W); 181. Big Lagoon Park, Humboldt (4109¢ N–12408¢ W); 182.
Humboldt Lagoons State Park (4116¢ N–
12406W); 183. Requa (4135¢ N–12405¢ W);
184. Talawa Lake (4150¢ N–12412¢ W); 185.
Kellog Beach (4152¢ N–12443¢ W); 186. Talawa
Lake Beach (4152¢ N–12413¢ W).
Oregon: 187. Samuel Boardman State Park
(4208¢ N–12419¢ W); 188. Pistol River State Park
(4216¢ N–12424¢ W);
189.
Gold
Beach
(4224¢ N–12425¢ W);
190.
Cape
Blanco
(4250¢ N–12433¢ W); 191. Bullard Beach State
Park (4308¢ N–12425¢ W); 192. Wiskey Run
Beach (4312¢ N–12424¢ W); 193. Seven Devil
Beach (4314¢ N–12424¢ W); 194. South Slough
National
Estuarine
Research
Reserve
(4318¢ N–12420¢ W); 195. Hornsfall Beach,
Oregon Dunes National Recreation Area
(4327¢ N–12416¢ W); 196. Shorewood, Coos
Bay (4327¢ N–12414¢ W);197. Bandom State
Park (4328,N–12413¢ W);198. Clear Lake
(4334¢ N–12411¢ W); 199. Umpkua Dunes
(4339¢ N–12412¢ W); 200. Salmon Harbor Dunes
(4340¢ N–12412¢ W); 201. Umpkua River, Gardiner (4343¢ N–12405¢ W); 202. Sparrow Park,
Oregon Dunes National Recreation Area
(4344¢ N–12411¢ W); 203. Threemile Creek, Siuslaw National Forest (4346¢ N–12408,W); 204.
Thakenitch, Oregon Dunes National Recreation
Area (4350¢ N–12409¢ W); 205. South Jetty,
Dunes City (4357¢ N–12408¢ W); 206. Heceta
Beach (4401¢ N–12407¢ W);207. Devil’s Elbow
State Park (4409¢ N–12407¢ W); 208. China
Creek (4410¢ N–12406¢ W); 209. Beachside State
Park (4423¢ N–12405¢ W); 210. Alsea Bay, Wadport (4426¢ N–12405¢ W); 211. South Beach
State Park (4436¢ N–12404¢ W);212. Moolak
Beach (4442¢ N–12403¢ W); 213. Beverly Beach
State Park (4444¢ N–12403¢ W); 214. Gleneaden
Beach (4452¢ N–12402¢ N); 215. Robert W.
Straub State Park (4511¢ N–12358¢ W); 216.
Cape Kiwanda State Park (4516¢ N–12359¢ W);
217. North Fork River, Nehalem (4524¢ N–
12353¢ W);
218.
Oceanside
(4527¢ N–
12359¢ N); 219. Tillamook Bay (4530¢ N–
249
12357¢ W); 220. Nehalem Bay State Park
(4541¢ N–12356¢ W); 221. Oswald West State
Park (4545¢ N–12357¢ W); 222. Ocean Beach,
Fort Stevens State Park (4611¢ N–12359¢ W).
Washington: 223. Long Beach, Willapa Wildlife
National Refuge (4636¢ N–12402¢ W); 224. Bay
Center (4637¢ N–12357¢ W); 225. Takeland,
Willapa Bay (4643¢ N–12401¢ W); 226. North
River (4644¢ N–12353¢ W); 227. Cranberry
State Park (4647¢ N–12405¢ W); 228. Grayland
Beach (4648¢ N–12405¢ W); 229. Twin Harbors
State Park (4651¢ N–12406¢ W); 230. Westport
State Park Beach (4654¢ N–12407¢ W); 231.
Westport State Park Wetland (4654¢ N–
12406¢ W); 232. Ocean City Beach (4704¢ N–
12410¢ W); 233. Copalis Beach (4707¢ N–
12410¢ W); 234. Eldon, Hood Canal (4730¢ N–
12303¢ W); 235. Kalahoch Beach (4742¢ N–
12425¢ W); 236. La Push Beach, Olympic National Park (4754¢ N–12438¢ W); 237. Rialto
Beach, Mora, Olympic National Park (4755¢ N–
12438¢ W); 238. Durgeness Spit Wildlife Refuge
Area (4808¢ N–12311¢ W); 239. Crescent Beach,
Olympic National Park (4809¢ N–12342¢ W);
240. Pillar Point (4812¢ N–12406¢ W); 241. Clallam Bay (4815N–12416¢ W); 242. Tsoo Yess
Beach, Makah Indian Reserve (4819¢ N–
12440¢ W); 243. Sooa River, Makah Indian
Reserve (4820¢ N–12439¢ W); 244. Bellinghan
Bay (4845¢ N–12235¢ W).
British Columbia: 245. French Beach Provincial Park (4824¢ N–12357¢ W); 246. China
Beach, Juan de Fuca Provincial Park (4826¢ N–
12405¢ W); 247. Sombrio Beach, Juan de Fuca
Provincial Park (4830¢ N–12410¢ W); 248.
Botanical Beach, Juan de Fuca Provincial Park
(4832¢ N–12427¢ W); 249. Combers Beach, Pacific Rim National Park (4902¢ N–12542¢ W);
250. Florence Bay (4900¢ N–12539¢ W); 251.
Chesterman Beach, Pacific Rim National Park
(4907¢ N–12553¢ W); 252. Ocean Beach, Pacific
Rim National Park (4908¢ N–12554¢ W); 253.
Bella Coola (5217¢ N–12635¢ W); 254. Bella
Coola Valley (5222¢ N–12644¢ W); 255. Log
Creek,
Skeena
Valley,
Port
Essington
(5412¢ N–12940¢ W); 256. Prince Rupert
(5421¢ N–12909¢ W).
Alaska: 257. Istmum Bay, Kodiak Island
(5736¢ N–15224¢ W); 258. Chinuak Lake, Kodiak
123
250
Island (5737¢ N–15211¢ W); 259. Salt Creek,
Kodiak Island (5739¢ N–15231¢ W); 260. Kalsim
Bay, Kodiak Island (5739¢ N–15226¢ W); 261.
Middle Bay. Kodiak Island (5739¢ N–15230¢ W);
262. Sargent Creek, Women Bay, Kodiak Island
(5742¢ N–15234¢ W); 263. Pillar Creek Beach,
Kodiak Island (5749¢ N–15226¢ W); 264. Monashka Creek Bay, Kodiak Island (5750¢ N–
15226¢ W); 265. Anton Larsen Bay, Kodiak Island
(5750¢ N–15238¢ W); 266. Gustavus, Glacier Bay
National Park (5823¢ N–13520¢ W); 267. Taiya
Inlet, Lynn Canal, Skagway (5929¢ N–13516¢ W);
268. Homer Spit (5936¢ N–15125¢ W); 269. Ninilchik State Recreation Area, Cook Inlet
(6002¢ N–15140¢ W); 270. Deep Creek, Ninilchick (6002¢ N–15142¢ W); 271. Toltsina Beach,
Caines Coastal Trail, Seward (6004¢ N–
14926¢ W); 272. Clam Gulf State Recreation
Area, Cook Inlet (6014¢ N–15124¢ W); 273.
Bishop Creek, Captain Cook State Park
(6047¢ N–15105¢ W); 274. Turnagain Arm, Portage Glacier (6051¢ N–14859¢ W); 275. Turnagain Arm (6056¢ N–14910¢ W); 276. Susitna
Flats (6115¢ N–15030¢ W); 277. Goose Bay
(6127¢ N–14930¢ W);
278.
Knick
Arm
(6127¢ N–14943¢ W); 279. Birchwood Lake
(6130¢ N–14930¢ W).
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