Grassland Ecology
Grasslands: are areas where the vegetation is dominated by grasses
Grassland ecosystems are fertile self sustaining habitats:
(Poaceae), however sedge (Cyperaceae) and rush (Juncaceae) families can
also be found. Grasslands occur naturally on all continents except
Antarctica. Grasslands are found in most eco-regions of the Earth. For
example, there are five terrestrial eco-region classifications (subdivisions)
of the temperate grasslands, savannas, and shrublands biome, which is one
of eight terrestrial eco-zones of the Earth's surface.
The nitrogen cycle is the series of processes by which nitrogen and its
compounds are interconverted in the environment and in living organisms,
including nitrogen fixation and decomposition
Rare Grassland habitats: Lowland unimproved neutral grassland is the
single most threatened type of grassland habitat in the UK and has suffered
the greatest loss in the last 70 years. The two principal vegetation
communities associated with unimproved neutral grassland is the National
Vegetation Classification (NVC) category of MG4, Mesotrophic Grassland
and the MG5: hay meadows and pasture community associated with more
free-draining neutral clay-based soils.
Some of the areas you will have seen or walked past at Flatford area
examples on unimproved neutral grassland.
The wild flower meadow
outside of the Edwards
classroom has a very high
diversity of plants and insects.
Because it is only mown once a
year to stop succession
occurring
and
otherwise
uninterrupted it is a very
special habitat.
Flatford Mill Field Centre. Registered charity no.313364
How would the sheep grazing around Flatford affect the nitrogen cycle?
What other factors may affect nitrogen cycling?
Mesotrophic: having a moderate amount of dissolved nutrients
Eco-region: an ecologically and geographically defined area that is
smaller than an eco-zone but greater than an ecosystem.
Eco-zone: is the broadest biogeographic division of the Earth's land
surface, based on distributional patterns of terrestrial organisms
Unimproved: having never been farmed, fertilized or artificially changed
Grassland Ecology
Grassland Trampling: The graph below shows information collected
from Miller’s Field detailing biotic and abiotic factors with distance away
from a trampled path. Use the knowledge you gained on your field trip
to interpret the data, draw a relevant graph to represent the information
and calculate a relevant statistical test to help you. Think about linking
the abiotic and biotic variables together and the synoptic science you
could use in your answer.
Ten quadrats were 1m intervals along both of the transects and the
frequency of each growth form of Ribwort Plantain.
Microhabitat
Growth form
Path
5m form path
Basal rosette
54
9
Upright
12
26
Distance from
centre of path/m
Mean soil compaction /
kgcm⁻²
Species
richness
0.0
4.5
8.0
0.5
3.3
7.0
1.0
3.2
7.0
1.5
3.5
6.0
2.0
3.0
6.0
2.5
2.7
5.0
3.0
2.1
4.0
3.5
1.8
4.0
4.0
1.5
4.0
4.5
1.1
3.0
Upright form
5.0
0.9
3.0
Phenotypic plasticity can be defined as the ability of one genotype to
produce more than one phenotype when exposed to different
environments. It is the ability of an organism to change its phenotype in
response to changes in the environment. In the case of Ribwort Plantain
explain how this type of growth variation is useful in either microhabitat.
Do some research into P. lanceolata how else is it adapted to survive in
trampled or hostile environments?
Further Data: This table shows the frequencies of two variations of the
plant Ribwort Plantain (Plantago lanceolata) in different areas of grassland.
Two transects were laid down, one on the path and one 5m away from the
path in a parallel line.
Flatford Mill Field Centre. Registered charity no.313364
Plot an appropriate graph and then use the data to calculate a chi2 test for
association. Interpret the data and suggest reasons for you findings.
Basal rosette formation