Acta Ecologica Sinica 32 (2012) 9–17
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Acta Ecologica Sinica
journal homepage: www.elsevier.com/locate/chnaes
Pathways of assessing agroecosystem health and agroecosystem management
Wenfeng Zhu a,1, Songliang Wang a,⇑, Claude D. Caldwell b
a
b
College of Crop Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Department of Plant and Animals Sciences, Nova Scotia Agricultural College, Truro, NS, Canada B2N 5E3
a r t i c l e
i n f o
Article history:
Received 17 September 2010
Revised 30 October 2011
Accepted 15 November 2011
Keywords:
Agroecosystem
Agroecosystem health
Agroecosystem health assessment
Agroecosystem management
a b s t r a c t
Intrusive agriculture development, searching for higher profitability, has inflicted permanent damage to
agroecosystems. Rapid deterioration of structure and functional properties in agroecosystems has intensified the need for research on agroecosystem health and agroecosystem management. This paper
describes the concept of agroecosystem health which plays an important conceptual role in evaluating
agroecosystem and agricultural research. Firstly, the development of agroecosystem health research is
reviewed, and agroecosystem health from various dimensions is provided. Then, the methods and general
criterias of agroecosystem health assessment are outlined, and a model for evaluating agroecosystem
health is established. Finally, pathways of agroecosystem management from a holistic dimension are proposed to promote agroecosystem health and provide a scientific basis for making science-based policy
decisions and formulating new plans in agricultural development.
Ó 2011 Ecological Society of China. Published by Elsevier B.V. All rights reserved.
1. Introduction
Agroecosystems, as complex, human-centered and special nature-economy-society three-dimensional ecosystems, play an
increasingly crucial role in human survival. However, especially
in the last century, agroecosystems have been regarded simply as
production units, rather than as muti-function ecosystems, causing
agriculture to become a major source of non-point source pollution
[1]. Well-meaning people have lost themselves in a mode of production dependent solely on high yield; this has caused serious
environmental problems (such as erosion of agricultural soils, pollution and overexploitation of fresh water, loss of biological diversity and increasing resistance of weeds and pests) all due to
inappropriate agroecosystem management [2]. For agroecologists,
it is high time to speed the development of agroecosystem research
and formulate appropriate management strategies to promote the
balance of natural systems with social and economic systems.
As ecologists increasingly emphasize the importance of assessment of agroecosystems as holistic systems, ecosystem health has
become a hot research field. Nowadays, there are many concepts
about ecosystem health. Agroecosystems are of multiple types
but need to be seen as holistic, human-centered, highly fluid, and
fragile. Agroecosystem health has caused particular concern as
we have seen a series of worldwide environmental problem appear
⇑ Corresponding author. Tel.: +86 591 87645506, + 86 13799419408; fax: +86
591 83727618.
E-mail addresses: [email protected] (W. Zhu), wsoloedu07@
126.com (S. Wang).
1
Tel.: +86 591 87645506, + 86 15859015441; fax: +86 591 83727618.
as a result of agricultural development. Okey noted that seven system properties lend themselves to a way of doing health interpretation. Five of these—stability, resilience, diversity, complexity,
efficiency and equality—are useful as a basis for defining agroecosystem health [3]. According to Haworth et al., the idea of a healthy
agroecosystem is understood from two perspectives. One is the
system-functions perspective, identifying the ideal state a healthy
agroecosystem would be in – that state in which all its health-relevant goals or norms are achieved; the other, the system-goals perspective, identifying the modes of functioning by which the system
is enabled to achieve those goals or norms [4]. An agroecological
framework to achieve crop health through agroecosystem diversification and soil quality enhancement, key pillars of agroecosystem
health was provided by Altieri and Nicholls [5]. Also, Xu and Mage
focused on assessing the applicability of assorted concepts, norms,
and criteria to agroecosystem health assessment and developed a
general definition of agroecosystem health, using southern Ontario
as a case study to further illustrate the applicability of the developed framework to agroecosystem health research [6]. A method
to quantify agroecosystem health through a combination of geographically referenced data at six key variables was described
and analyzed by Vadrevu et al. These biophysical and socioeconomic variables were hypothesized to provide a minimum set of
conditions required to quantify agroecosystem health: soil health,
biodiversity, topography, farm economics, land economics, and social organization. They also make extensive use of Geographic
Information System (GIS) software and spatial analysis techniques,
so that the resulting map of agroecosystem health can be interpreted according to the underlying data and its spatial patterns
[7]. More researchers were devoted to the exploration of the
1872-2032/$ - see front matter Ó 2011 Ecological Society of China. Published by Elsevier B.V. All rights reserved.
doi:10.1016/j.chnaes.2011.11.001
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W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
frontiers of agroecosystem health study, analyzing the concept of
agroecosystem health, establishing agroecosystem health evaluation model and an index system, and further applying them in
practice. There are, however, problems of agroecosystem health research such as: lack of uniform definition and assessment standards
of agroecosystem health; difficulty in establishing a systematic and
scientific evaluation index system has become the bottle-neck of
agroecosystem health research; progress of agroecosystem health
research is hindered by the leading role taken by subjective and economic factors; the need for methods of combining the qualitative
analysis with quantitative analysis in agroecosystem health study;
few studies attempting to link agroecosystem health to agroecosystem management, which is the key factor in agroecosystem sustainable development. The present paper aims to provide concepts and
interaction between agroecosystem health and agroecosystem
management, and further to establish a science-based agroecosystem health evaluation system and give proper guidance for agroecosystem management, so as to provide a basis to support agricultural
management and the relevant policy decision making.
2. Conceptual model of agroecosystem health
2.1. Agroecosystem
Agroecosystems, as interfaces of human society and natural
ecosystem, are defined as ecological and socioeconomic systems
and communities of plants and/or animals interacting with their
physical and chemical environments that has been modified by
people to produce food, fiber, or other agricultural products for
human consumption and processing [3,8–10]. However, agroecosystems are major ecological units, with flow and cycling of materials and energy rather than simple produce units. Agroecosystems,
as important components of larger ecosystems, have both universality and individuality among ecosystems. When compared with
natural ecosystems, agroecosystems have been endowed with
those characteristics such as high fluidity, vulnerability, spatiotemporal difference, poor stability and low biodiversity.
2.2. Ecosystem health
Ecosystem health, a concept used in ecosystem analysis and
management, describes a condition or property of an ecosystem
in a similar way as we consider human health. Serious environmental pollution affects human health; the concept of health is
introduced into ecology from the human and plant field, and has
become the intersection of environmental science and medical research. Then environmental health science and environmental
medicine begin to appear and develop. The ecosystem health evaluation metaphor provides a useful language, with terms such as
signal, diagnostic index, dysfunction, and disease, and these terms
are familiar to the public. ‘‘Ecosystem health’’, as a concept, was
initially developed from the definition of ‘‘land health’’ proposed
by a natural scientist Leopold in the early 20th century [11]. A land,
completely regarded as an ecosystem, was the net of relationship
between organisms and the environment.
As the degradation of the global ecosystem is increasing, it is
worthwhile to pay more attention to the study of the issue ecosystem health. Researchers give different definitions toward ecosystems that may be summarized as follows: (1) Ecosystem health, as
a state of an ecosystem development, must include the human as a
part of the ecosystem, and take impact of demography into
account. (2) A healthy ecosystem should meet six properties:
vibrant (metabolism), organization (diversity), resilience, productivity, stability (coordination) and the sustainability. (3) Ecosystem
health has limitations of scale and growth of space, and must adjust
measures to local conditions. (4) The objective of the application of
the ecosystem health concept is to manage the resource [12,13].
We believe that ecosystem health is a state in the process of
ecosystem variation with time and space. A healthy ecosystem
can protect itself from effects of occurrence of ‘‘disorder syndrome’’, and it keeps vitality and diversity, coordinating its stability of organizational structure and maintaining high productivity.
Under external stress, a healthy ecosystem is better able to restore,
and promote the optimization and efficient use of resource.
2.3. Agroecosystem health
Agroecosystems are important components of the larger ecosystem. Ecosystem and agroecosystem have homogeneity, while
each of them has its own specialty. The main difference between
agroecosystems and other ecosystems is its human participation.
It is a complex integrated nature-economy-society four-dimensional system (note that they change over time – the 4th dimension-naturally). Therefore, we have to take full account of its
characteristics in the process of defining agroecosystem health.
We believe that agroecosystem health is an ideal condition in the
process of agroecosystem variation with time and space. A healthy
agroecosystem can keep itself from side-effects of occurrence of
‘‘disorder syndrome’’, and it keeps vitality and diversity, coordinating its stability of organizational structure and maintaining high
productivity. In non-human external stress, its efficient use of resources can keep the continuous production and service capacity
for the entire ecosystem. We can describe agroecosystem health
in terms of dynamic properties including vigor, organization structure, resilience (maintenance), equality (noted that it is special
characteristics of agroecosystems as human-participated ecosystems) [8,10,13].
Agroecosystem health research includes the following aspects:
Evaluation of agroecosystem health, linkages between soil quality,
water quality and agroecosystem health; relationship between
agroecosystem health and the human health; the contribution of
management such as Integrated Soil Management (ISM) and Integrated Pest Management (IPM) to agroecosystem health; ecological
impacts of biological indicator, genetically modified crops (transgenic crops) in the agroecosystem health; roles and impacts of
agricultural inputs, agroecosystem health policy and landscape
ecology in the agroecosystem health evaluation; relationship
between agroecosystem health and green food development.
3. Evaluation model of agroecosystem health
3.1. Principles of agroecosystem health assessment
Since agroecosystems are complex and multi-level system, their
health status assessment is not properly carried out only with two
or three indices. It is necessary to choose several evaluation indicators fully reflecting health status from parts to whole. Agroecosystem health assessment needs comprehensive analysis of
evaluation objectives and an assessment index system must follow
the principles below:
(1) Comprehensive principle. An agroecosystem health indicator system, as a holistic integrity, should reflect all aspects
of a comprehensive state; however, it is not useful to choose
every factor in an agroecosystem as an evaluation index. But
we need to select the indicators that embody a concentrated
reflection of the main features of the agroecosystem according to different circumstances.
(2) Quantified and comparable principle. Quantified and comparable agroecosystem health is not a single, static state, but
rather a dynamic body interacting and interconnecting with
W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
factors around the agroecosystem. Therefore the selection of
indicators needs to consider differences between time and
space, reflecting the rigorous path of agroecosystem health
and both advantages and disadvantages compared to others.
(3) Simplifying the operation. Selected indicators must be simple, easy to grasp and easy to extend.
3.2. Methods of agroecosystem health assessment
Compared with limitations of traditional environmental assessment methods that only focus on physical and chemical parameters and biological detection technology, agroecosystem health
assessment, as a cross-scientific practice, usually needs the assistance of a multi-disciplinary approach integrating medicine, ecology, economics, agriculture and sociology to diagnose and
evaluate health status. It includes not only the integration of system, community, population and individual level, and other multi-scale ecological indicators to reflect the complexity of
ecosystems, but also integrates the physical and chemical indicators, as well as socio-economic, human health indicators, so as to
reflect the quality and sustainability for agroecosystems, providing
agroecosystem services for human society and its global health status. Agroecosystem health evaluation can be carried out from diagnosis of agroecosystem disorder syndrome, assessment of the
buffering capacity and the continuity of agroecosystems, ecological
risk, and agriculture itself. Agroecosystem health assessment not
only needs to monitor its small-scale ecological processes, the
landscape scale for environmental quality monitoring is also an
essential step.
3.3. Framework of agroecosystem health assessment
3.3.1. Selection of evaluation indices
The concept of health lies in the centre of agroecosystem health
assessment. As an evaluative notion, assessing the health of any
system demands a set of criteria related to the structure, function,
organization, and dynamic aspects of the system (Xu and Mage)
[6]. Currently, a variety of index systems have been constructed
to study agroecosystem health. Conway has proposed comprehensive evaluation indices to analyze agroecosystem health; the key of
the method is to achieve the organic combination of four kinds of
characteristics of productivity, stability, sustainability and equality
at different levels in agroecosystems [10]. Since an agroecosystem
is a human-centered system, effects of human factors on agroecosystem health are also essential to be considered. As shown in
Fig. 1, six indicators (reserves, consumption, production, satisfaction, socioeconomic integrity, and resources) with low, medium,
and high designations are relevant to agroecosystem health assessment [14].
In terms s of agroecosystem functions and goals, an agroecosystem as a whole, can be formed from three subsystems: Social System, Economic System and Biological Ecosystem (Haworth et al.)
[15]. In this review, according to advances of agroecosystem health
and its assessment studies, by mean of the Delphi technique, a
widely used qualitative predicative method, a four-stage framework of agroecosystem health assessment system is proposed
(Fig. 2).
Using comprehensive, quantified and comparable principles to
simplify the operation, 60 indices that can reflect agroecosystem
status both in parts and whole are selected for Specialist Grading.
After two rounds of Delphi investigations, 36 indicators are selected and separated into layers following a logical approach. The
first level is ‘Object’: Evaluation objectives and Composite Index
of agroecosystem health; The second level is ‘Item’: subsystem in
an agroecosystem, including economic system, societal system,
biological ecosystem; The third level is the evaluation factors: spe-
11
cific elements for every evaluation item, characteristics including
Vigor, Organization structure, Resilience (maintenance) and Equality in each subsystem. The fourth level is index level: detail indicators to express each evaluation factors to form macroscopical,
mesosphere and microcosmic dimensions.
3.3.2. Application of AHP in confirming the weight of indicators
After agroecosystem health assessment indicators are selected,
it is essential to decide index weighting which reflects its relative
importance to agroecosystem health and to management goals.
There are many ways of giving the weight to the index. However,
starting points for various methods and solutions to problems
are different; they have respective standpoints and shortcomings,
being used for different research objectives. At present, the specific
method of index weight coefficient are Gray interconnected analysis, Analytic hierarchy process (AHP), Artificial neural network
method, Delphi method and Fuzzy cluster analysis method. The
AHP, proposed by American operational researcher Saaty, has been
applied in a broad range of environmental impact assessments,
catchment management planning, land use planning, and natural
resource studies [16–20]. APH concerns the decomposition of a
complex into different factors and combining them according to
different levels, in order to establish a multi-level structural analysis model. Finally, system analysis could be attributed to the relative importance weights between lowest level and highest level
or sequencing of relative merits in the system analysis. So it is used
to establish a more complete and accurate agroecosystem health
evaluation system. According to Saaty, the general approach using
APH is outlined as follows [21]:
(1) Establish layer structural model. Based on feedback of
experts with the Delphi technique, modeling agroecosystem
health assessment as a hierarchy and establish integrated
layer structural model. Structure the problem as a hierarchy
of goal, criteria, sub-criteria, and alternatives.
(2) Start by the second level of the hierarchy. Construct judgment matrix and determine the largest eigenvalue and
eigenvector. Do pair-wise comparison of all elements in
the second level and enter the judgment matrix. Calculate
priorities by normalizing the vector in each column of the
matrix of judgment and averaging over the rows of the
resulting matrix and you have the priority vector. If a 2–2
matrix is set to (aij) n n, aij>0; aij = 1/aji = 1, 2, 3, . . . n. specific method of judgment matrix construction in all levels
is outlined as following: Based on elements (Social System,
Economic System and Ecosystem) in the item layer (layer
II) of health assessment system, Pair-wise comparison of
attributes at each level with respect to each criterion at
the proceeding level and computing the local priority vector
for each matrix of judgment. For instance, Social System is
more important than Economic System, Ecosystem is more
important than Economic System, etc. Construct judgment
matrix I1–I2 in this way. We can quantify the judged results
by refer to 1–9 scaling on materiality, scale as shown in
Table 1.
(3) Compute the consistency ratio of the matrix of judgments to
make sure that the judgments are consistent.
(4) Repeat step 2 for all elements in a succeeding level but with
respect to each criterion in the preceding level. And Construct (I2–I3), (I3–I4) comparison matrix.
(5) Synthesize the local priorities over the hierarchy to get an
overall priority for each alternative.
However one decides index weighting, one must adjust measures to local conditions. Researchers should choose proper index
weights according to different actual circumstances.
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W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
Consumption
high
medium
low
Reserves
Production
low
medium
Inefficiency
high
low
medium
Inadequate
Healthy
Resilience
Agroecosystem
high
high
medium
Satisfaction
Inadequate
Ineffectiveness
Integrity
low
low
medium
Resources
low
medium
high
high
Socioeconomic integrity
Fig. 1. Fuzzy logic model of agroecosystem health [14].
health trends; Wij represents weighting coefficients in different levels; Mij represents evaluation of numerical scores in different levels.
Economic
system
Vigor
Organization structure
Meso Dimension
Social system
Macro Dimension
Ecosystem
Micro o Dimension
Agroecosystem Health
Resilience (maintenance)
Equality
Fig. 2. Four-stage framework of agroecosystem health assessment system.
Table 1
Saaty’s scale of preferences in the pair-wise comparison process [17].
Numerical
rating
Verbal judgments of preferences between alternative i and
alternative j
1
3
5
7
9
i
i
i
i
i
2.4.6.8
Intermediate values
is
is
is
is
is
equally important to j
slightly more important than j
strongly more important than j
very strongly more important than j
extremely more important than j
3.4. Comprehensive evaluation (AH) method
System analysis and Mathematical model are effective ways of
evaluation. Based on evaluation index systems of agroecosystem
health, according to composite assessment index system of agroecosystems health (Table 2), it needs giving scores and calculating
from the low level to high level, and finally composite to a specific
value. Its mathematical expressions are as follow:
H¼
X
W ij M ij
ði; j ¼ 1; 2; . . . nÞ
where H stands for agroecosystem health index, It cannot only be
used to characterize different regional agroecosystem health state,
but can also be used to analyze the same area for agroecosystem
4. Pathways of agroecosystem management
4.1. Agroecosystem management concept
Many people and organizations have defined ecosystem management. The following examples represent a cross-section of definitions. There are two themes common to most of these
definitions of ecosystem management [22–25]: (1) management
should maintain or improve ecosystem health; (2) ecosystems
should provide a range of goods and services to current and future
generations; (3) ecosystem management needs systematic thinking, maintenance of ecological structure and function, scientific
data in both planning and monitoring, and consideration of human
values and institutions.
Agriculture is an ecosystem that is frequently disturbed to favor
desired products. What ecologists call ‘‘human disturbance’’ such
as tillage and herbicides preventing competition from undesired
weeds and veterinary care and housing protecting livestock from
pathogens and predators, agriculturalist call ‘‘management’’ [26].
Agroecosystem management is an expansive concept that is based
on fully understanding agroecosystem composition, structure and
the process of ecosystem function, combining disciplines such as
agroecology, economics, sociology and management theory, making adaptive management strategy to realize the sustainable utilization of resources and to restore or maintain agroecosystem
integrity with high biodiversity and sustainability, and keep a
healthy agroecosystem.
4.2. The interaction of agroecosystem health and agroecosystem
management
Agroecosystems are the basis of Earth’s life support systems. As
an compound ecological and socioeconomic systems, its develepment, to some degree, depends on the state of agroecosystem
health and management and their mutual relationship. Agroecosystem health plays a great role in the stability of the entire agriculture and sustainable development of human society.
Agroecosystem health research provides scientific basis and a diagnostic tool for the monitoring and management of agroecosystems.
W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
13
Table 2
Composite assessment index system of agroecosystem health.
Objective
Items
subsystem
Evaluation elements
Detail indicators/standard value
The over goal agroecosystem
health
Ecosystem
Vigor
Light use efficiency of crop (P1/%)*
Organization
structure
Resilience
(maintenance)
Equity
Social system
Vigor
Organization
structure
Resilience
(maintenance)
Equity
Economic
system
Vigor
Organization
structure
Resilience
(maintenance)
Equity
*
Percent age of effective irrigation farmland area (P90%)
Sustainability of soil fertility(class 2)
Percentage of condition up to par (P90)
The strength of pesticide use (65 kg/h m2)
Crop-biodiversity in over cropping (P1.585)
Treatment rates of Soil erosion (P60%)
Proportion of saline and alkaline area (65%)
Agroecosystem resilience to general disaster (rate of yield loss 6 10%)
Pesticide chemical and fertilizer usage per unit area of (6250 kg/h m2)
Grasslands area per capita (P0.69 h m2/person)
Farmland area per capita(P0.32 h m2/person)
Degree of satisfaction on policy validity (P90%)
Contribution rate of science and technology in agriculture (P39%)
The natural rate of population growth (P6‰)
Satisfaction with social security of villagers (P85%)
Rate of consumer price index increase (65%)
Male-to-female ration (6106/100)
Labor force quality (rate of high school graduate or above) (P15%)
Rate of scientific and technical personnel (P0.4‰)
Food security (the rate of certification origin-friendly agricultural products number
increase) (15%)
Coverage of old age insurance (P60%)
Gini coefficient 6 (0.3)
Engel coefficient (P0.3, 60.4)
Rate of agricultural output growth (P10%)
Comprehensive utilization degree of natural resources (P10%)
Increase percent of grain yield (P0)
Output/ input ratio of agroecosystem (62.8%, P1.8%)
Percentage of cash crop area (630%)
Irrigation water efficiency index (P0.55 m2/million Yuan)
Area of ensure stable yields despite drought and excessive rain (P50%)
Energy self-sufficiency rate (P85%)
Cropping index (P150%)
Net income per villager (P2500 Yuan/per capita)
Disposable income per capita (P24000 Yuan/per capita)
Grain per capita (P500 kg)
Value scope of the index shown in the parentheses.
Meanwhile, recent agroecosystem management often interferes
with agroecosystem health. Rational human intervention can produce a good system and sustainable development, while irrational
human intervention will result in system damage, ecosystem degradation, and ecological disaster. Agroecosystem health and agroecosystem management are interdependent and mutually
supportive. They are united in the pursuit of agricultural sustainable development.
4.2.1. There is a coincidence between the ultimate aims of
agroecosystem health and agroecosystem management
Agroecosystem health is not a science per se but in its most
general conception can be viewed as a kind of sustainable development state, aiming at agroecosystem prediction and management.
And its ultimate goal is to promote healthy and stable services
functioning, the sustainable development of human society and
stability of the entire agriculture. While agroecosystem management, focusing on sustainability and the proper relationship that
should be maintained between environment and development,
whose goal is achieving reasonable and effective use of agriculture
resources and the sustainable development of society and economy, as well as to restore degraded agroecosystem to healthy
compound ecosystem. By this token, it is unanimous that the final
goal of the two is consistent, namely sustainable development.
4.2.2. Agroecosystem health offer scientific tools and guidance to
implication of agroecosystem management
Current methodological approaches for agroecosystem
researching are insufficient to address the goals of agroecosystem
management. In order to move toward implementing agroecosystem management, a better understanding of the relationships between institutions and natural resource management and
advanced methodological approaches will be required [27]. Agroecosystem health is systematic quantitative assessment of the extant variations in ecosystem and human conditions for appropriate
spatial units of analysis relevant to economic, environmental, and
natural resource decision making. Being regarded as an essential
tools to realize the target of agroecosystem management, it provide new ideas and methods to agroecosystem management. The
agroecosystem health assessment result will be useful for policy
makers, land owners, farmers, and other land managers to understand how their combined efforts can lead to improved agroecosystem health. For example, the discretion of the numerical
evaluation indexes from different levels well reflect agroecosystem
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W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
problems from government policy, system structure and
organizations.
The evaluation results can provide a basis for the reasonable
conjectures of the change of eco-environment and its driving force,
and summary of the spatial-temporal evolution. Thus is used
for management strategies from the microscopic level as well as
macroscopic level. (1) From the longitudinal view agroecosystem
health evaluation could be a continuous process. By using the
dynamic index, general level of the health state in different periods
will be analyzed, and the comprehensive evaluation of agroecosystem will be realized. Then based on the analysis of agroecosystem
health stress factors and the assessment and monitoring of a
certain period agroecosystem health status and development trend,
the government could measure success and failures of agriculture
policy, determine restore priorities of agroecosystem management
process, and apply a series of active and significant step to bring
conduction band to move a farmer to adjust agricultural construction [28]. (2) From the crosswise view, agroecosystem health could
reflect the spatial distribution difference of agroecosystem. By
establishing an fairly unified standard, and relatively objective
and rigorous evaluating system, agroecosystem health state can
be compared in different regions. It is propitious to adopt suitable
technologies and management policy according to actual condition.
The agroecosystem management capacity could be improved in
comparison with other regions.
4.2.3. Agroecosystem management is a most effective way to achieve
agroecosystem health
Being different from other natural ecosystems, Agroecosystems,
as typical economic-natural-social composite ecosystems, are human-centered, and are always under Anthropogenic disturbance
and management. Thus it is nearly impossible to address the goals
of agroecosystem health and agricultural sustainability. In fact, the
health state of an agroecosystem is fundamentally affected technology, policy, economy, culture and other management factors.
However, agroecosystem management could provide an effective
framework for integrated resource assessment and management
of agroecosystems. Normally, state of agroecosystem health depends on its management level.
To resolve agroecosystem health problems, human beings is
the key to improve the ecological environment and to defuse the
eco-crisis. For the human managers, thinking in terms of system
functions, the goal guides them in an effort to build practices and
institutions that put in place a sort of integrity, resilience and
efficiency that orks for the flourishing of the entire biotic community, nonhuman as well as human [15]. Ideally there should be a
congruent decision making mechanisms that can negotiate and
decide on health goals based on ecological mechanisms. At the same
time, improving and making full use of the market mechanism and
public participation mechanism and regarding legal mechanism
as the ultimate security, is the core content of agroecosystem
management, as well as the practical path of agroecosystem health.
4.3. Agroecosystem management model
Through the application of agroecological principles, the basic
challenge for managing sustainable agriculture to maintain the resource, relies on a minimum of artificial inputs from outside the
farm system, good nutrient cycling within the system with few
‘‘leaks’’, management of pests and diseases through internal regulating mechanisms, and is able to recover from the disturbances
caused by cultivation and harvest [3,27,29]. Achieving this goal
to promote agroecosystem health, requires an integrated agroecosystem management model linking micro- and macroscopically
level (Fig. 3). Its essence could be described as following:
(1) The goal of agroecosystem management is to pursue balance
and coordination among ecological, social and economic systems, ensuring that the agroecosystem services are healthy
within limits of tolerances of agroecosystem, achieving sustainable utilization of resource and sustainable development
of agriculture.
(2) The nature of agroecosystem management is to maintain
and balance vigor, organization structure, resilience (maintenance), equality of the system, though regulating natural
resources and energy flows.
(3) Management model should be designed in line with local
conditions. Designing an agroecosystem management model
adapted to the local environment, making full use of information technology, biotechnology and ecological engineering technology to carry out Integrated Plant Nutrient
Management, Soil Management, Water Management, and
Pest Management. Agroecosystems are artificial systems
characterized with a high human participation; thus artificial factors in agroecosystem management must be
considered.
(4) Agroecosystem management should combine disciplines
such as agroecology, economics, sociology and management
theories. It could be realized from two levels as following:
4.3.1. Microscopic management
According to agroecological theories, the optimal behavior of
agroecosystems depends on the level of interactions between the
various biotic and biotic components [30]. Natural resources, such
as solar, air, water, soil, flows circulated or recycled by means of
energy, material, information flows in an agroecosystem, along
with formation of agroecosystem service. Therefore, agroecosystem management can be put into effect by regulating these flows,
to achieve the most efficient use of energy and resources in an
agroecosystem in essence [31]. Some promising traditional management, although valuable, focus on pursuit of production, rather
than long-term health of whole agroecosystem. Fig. 3 provides a
list of recommended and/or experimental practices (focus on technical aspect).
(1) Integrated Plant Nutrient Management (IPNM). IPNM is a
system used by farmers to manage the amount, source,
placement, form, and timing of the application of nutrients
(whether as manure, commercial fertilizer, or other forms
of nutrients) and soil amendments to plants. The purpose
is to supply plant nutrients for optimum forage and crop
yields, to minimizing non-point source pollution (runoff of
pollutants to surface water, etc.) and contamination of
groundwater, and to maintain and/or improve the condition
of soil [32,33]. IPNM (such as manure, compost, artificial
enrichment with CO2, genetic selection or inhibition of
photo respiration and night respiration) can either improve
the nutrient balance or minimize the negative impact of
the nutrient imbalance, playing an important role in all levels of agroecosystem. Besides, by carefully managing nutrient and pesticide use, water quality can be maintained or
improved.
(2) Integrated Soil Management (ISM). Soil Quality is a critical
factor in the management of natural resources. It provides
many essential ecosystem functions, such as providing a
medium for plants to grow in, absorbing, filtering, and
slowly releasing water, recycling nutrients and organic
wastes, and storing and releasing greenhouse gasses [31].
ISM prevents or reduces the discharge of pollutants to storm
water from contaminated soil and highly acidic or alkaline
soils by conducting pre-construction surveys, inspecting
excavations regularly, and remediating contaminated soil
15
W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
Microscopic
Management
Energy flow
Material flow
Information flow
Solar
Air
Water
Soil
Agroecosystem health Assessment
Macroscopical
Management
Agroecosystem Structure
and Its Services
Nutrient Management
Economic
Service
Soil Management
Ecology
Service
Integrated pest Management
Water Management
Social
Service
Policy orientation
Policy and Formulas
Standards
Government control
Specific Technology
Green manure/ Composting
Reduced tillage /Legume Crop
Drip irrigation/Windbreaks
Agroforestry/Intercroping
Pest enemies/ Trap plants
Biological pesticides/Mulching
Resistant varieties/Crop rotations
Multiple cropping system
Producers
Produce Idea
Change
Market Regulation
Driving force
Overall Health
Objectives
Technical Management
Organization
structure
Vigor
Resilience
(Maintenance)
Equity
Economy driving form
Systemic driving force
Social driving force
Cultural driving force
Consume Idea
Change
Consumers
Ecosystem
Health
Hypostasis of
Agroecosystem
Management
Fully Understand of
agroecosystem
Agroecology
Combine disciplines
Resources
Sustainable utilization
Social system
Economic system High biodiversity
Agroecosystem
Health
Health
Service functioning well
Fig. 3. Agroecosystem management model.
promptly. ISM can be put into effect through: (a) minimum
or reduced tillage; (b) mulch the soil year round to minimize
the compaction forces of rain and sprinkler irrigation: (c)
add organic matter to clayey soils; (d) avoid cultivating or
working a clayey soil when wet; Use a raised bed with established walkways, and avoid walking on the growing bed; (e)
increase nitrogen contributions from legumes; (f) use of
manure or cover crops [3,34].
(3) Integrated Water Management (IWM). The lack of water
resources, water disaster and water pollution increased with
agriculture development. The best solution to this increasing
demand involves developing water management technologies to conserve and use the existing water resources more
efficiently and prevent from unnecessary water fouling.
Existing agricultural water management technologies, such
as drip irrigation, mulching, reduced tillage, windbreaks
cover management for shade control and water harvesting,
have the potential to double, even quadruple rain-fed crop
yields.
(4) Integrated Pest Management (IPM). Agricultural pests (i.e.,
weeds, fungi, vertebrates) have been already major constraints to the development and expansion of agriculture.
This can be solved by IPM. IPM refers to a comprehensive
approach to pest control that repeated application of pestmonitoring and control technology to reduce the economic
impacts of diverse insects, pathogens, nematodes, weeds,
and vertebrates that damage agriculture while maintaining
a quality environment [35,36]. These methods are performed in three stages: prevention, observation, and intervention. IPM is an ecological approach with a main goal of
significantly reducing or eliminating the use of pesticides
while at the same time managing pest populations at an
acceptable level. Using preventive practices that don’t
involve pesticides such as crop rotation, planting pest resistant varieties, removal of alternate hosts that may harbor
pests, exploring the pest enemies, Least-toxic Herbicides
and Weeder geese, Preplant tillage, Blind tillage, Interrow
cultivation, Flame weeding, and planting of native plants
16
W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
which attract beneficial insects are means of implication of
IPM [3].
4.3.2. Macroscopic management
According to Caldwell et al. [37], Agriculture is the science, art,
politics and sociology of changing sunlight into happy, healthy
people. Therefore, agroecosystem management is not only relationship between biotic and non-biotic in a farm, but also practices
derived by the economic driving force, systemic driving force, social driving force, cultural driving force, orientated by policy, and
linking producers and consumers. Thus, a good agroecosystem
management strategy can achieve its goals through implementing
the following mechanisms [38]:
(1) Decision making mechanisms. Sustainable agroecosystem
management is orientated by policy, formulas, standards,
government control, and legal. It is essential to enhance
the design and construction level of government scientific
ecological planning. Government should play the role of
judges in production areas, developing agroecosystem management rules and implement the management system of
‘‘dynamic adjustment and survival of the fittest’’; while in
allocation and consumer areas, government should act as a
facilitator, guiding the consumer to establish green and scientific consumption idea. Government supervision and the
relevant law are the assurances to implement the agroecosystem health management.
(2) Legal Mechanism. Legal mechanisms are an indispensable
part to achieve sustainable management goal. Laws are to
lay the groundwork for establishing the agroecosystem
management decision making process, rather than the absolute standard of the implementation [39].
(3) Participatory Mechanism. Agroecosystem management
should strengthen the collaboration of all forces in the development of agroecosystem management decision, to enhance
ecological and environmental awareness of shareholders
(consumers and producers), to strengthen the research
capacity of technology and to make public supervision function well, so as to promote the implication of agroecosystem
management.
(4) Ecological Mechanism. Objectives of agroecosystem management are to coordinate the stable productivity and sustainability of the ecological environment, implementing a
win-win healthy state. Based on good understanding ecological processes of agricultural production, taking full advantage of the nature steady-state mechanism (Homeostasis),
comprehensive human social forces (multidisciplinary
knowledge), establish an effective ecological mechanism is
necessary. That is to say, on the basis of agriculture, ecology,
informatics, meteorology, economics and other disciplines:
(1) establish a set of environmental system evaluation indicators and promote the improvement of a ‘‘green’’ agricultural indicator accounting system; (2) establish ecological
compensation system [40]: an ecological compensation system is a kind of system principally through increasing
charges (or increasing compensation) of behaviors damage
(or protection) resource and environment, so as to improve
the cost (or revenues) of external economy effects and to
realize the goals of environment and resource protection,
and ecosystem health.
5. Conclusion
Agroecosystem health is, to some degree, a suitable criterion for
decision-making in agroecosystem management. It is an evaluative
concept intended to integrate a complex reality of different human,
socioeconomic factors and biophysical phenomena and processes
at a variety of scales [41]. Above all, there is a need for rigorously
defining agroecosystem health and management as well as establishing a systematic, scientific and comprehensive assessment
indicator system. This article proposes demonstrates, that combining the Delphi method and AHP can be used to integrate quantitative research and qualitative research, so as to provide a scientific
basis for agroecosystem management, at both in the micro and
macro levels. However, we should note that it would be better to
use a case-study. Besides, there is a need to combine the micro
and macro-comprehensive research, so as to promote combining
Remote Sensing (RS), Global Position System (GPS) with Geographic Information Systems (GIS), making principles of landscape
ecology and other means of macro-technological closely coordinated with the ground study, in order to understand changes in
agroecosystem structure, their functions and processes as one of
the best ways of agroecosystem health assessment. In addition,
the discipline of agroecology guides and promotes dialogue among
economists, sociologists and ecologists, and changes an economic
benefits-centric development model into a sustainable development model; this is the ultimate goal of this study.
Acknowledgements
The project was financially supported by National Natural Science Foundation of China (No. 30571138) and National Natural Science Foundation of Fujian province in China (B0520001).
References
[1] T. Prato, C. Fulcher, S. Wu, J. Ma, Multiple-objective decision making for
agroecosystem management, Agricultural and Resource Economics Review 25
(1996) 200–212.
[2] D. Tilman, Global environmental impacts of agricultural expansion: the need
for sustainable and efficient practices, in: Proceedings of the National Academy
of Sciences, USA, vol. 96, 1999, pp. 5995–6000.
[3] M.A. Altieri, Agroecology: The Science of Sustainable Agriculture, Westview
Press, Boulder, CO, 1995.
[4] B.W. Okey, Systems approaches and properties, and agroecosystem health,
Journal of Environmental Management 48 (2) (1996) 187–199.
[5] M.A. Altieri, C.I. Nicholls, Ecologically Based Pest Management: A Key Pathway
to Achieving Agroecosystem Health (2003) 999–1010.
[6] W. Xu, J.A. Mage, A review of concepts and criteria for assessing agroecosystem
health including a preliminary case study of southern Ontario, Agriculture,
Ecosystems & Environment 83 (3) (2001) 215–233.
[7] K.P. Vadrevu, J. Cardina, C. Hitzhusen, et al., Case study of an integrated
framework for quantifying agroecosystem health, Ecosystems 11 (2008) 283.
[8] G.R. Conway, Agroecosystem analysis, Agricultural Administration 20 (1)
(1985) 31–55.
[9] G.R. Conway, Agroecosystem Analysis for Research and Development, Winrock
International Institute for Agricultural Development, Bangkok, Thailand, 1986.
[10] G.R. Conway, The properties of agroecosystems, Agricultural Systems 24
(1987) 95–117.
[11] A. Leopold, Wilderness as a land laboratory, Living Wildness (6) (1941). 6.3.
[12] D.J. Rapport, What constitute ecosystem health?, Perspectives in Biology and
Medicine 33 (1989) 120–132.
[13] D.J. Rapport, R. Costanza, A.J. McMichael, Assessing ecosystem health, Trends
in Ecology & Evolution 13 (10) (1998) 397–412.
[14] J.E.B. Bellamy, D. Waltner-Toews, N.O. Nielsen, Agroecosystem Health: a Fuzzy
Systems Approach. Discussion Paper 30, Agroecosystem Health Project,
University of Guelph, 1996.
[15] L. Haworth, C. Brunk, D. Jennexand, et al., A dual-perspective model of agroecosystem health, system functions and system goals, Journal of Agricultural
and Environmental Ethics 10 (1998) 127–152.
[16] A.R. Banai-Kashani, New method for site suitability analysis-the analytic
hierarchy process, Environmental Management 13 (1989) 685–693.
[17] A.R. Banai-Kashani, Fuzziness in Geographic Information System,
contributions from the analytic hierarchy process, International Journal of
Geographical Information 7 (4) (1993) 315–329.
[18] X.N. Xiang, D.L. Whitley, Weighting land suitability factors by the PLUS
method, Environment and Planning B: Planning and Design 21 (3) (1994) 273–
304.
[19] C.B. Alphonce, Application of the analytic hierarchy process in agriculture in
developing countries, Agricultural Systems 53 (1) (1997) 112.
[20] N.C. Bantayan, I. Bishop, Linking objective and subjective modeling for land use
decision-making, Landscape and Urban Planning 43 (1-3) (1998) 35–48.
[21] T.L. Saaty, The Analytic Hierarchy Process, McGraw-Hill, New York, 1980.
W. Zhu et al. / Acta Ecologica Sinica 32 (2012) 9–17
[22] J.K. Agee, D.R. Johnson, Ecosystem Management for Parks and Wilderness,
University of Washington Press, Seattle, 1988.
[23] Forest Ecosystem Management Team (FEMAT), Forest ecosystem
management: An ecological, economic, and social assessment, What is
ecosystem management? Conservation Biology 8 (1993) 27–38.
[24] R.E. Grumbine, What is ecosystem management, Conservation Biology 8 (1)
(1994) 27–38.
[25] R.E. Grumbine, Reflections on ‘‘What is ecosystem management?’’,
Conservation Biology 11 (1) (1997) 41–47.
[26] S.M. Swinton, Reimagining Farms as Managed Ecosystems, Choices 23 (2)
(2008) 28–31.
[27] J.C. Hanna, G.W. Mary, B. Sabrina, A.M. Margaret, Institutions matter: the need
to address the institutional challenges of ecosystem management, Landscape
and Urban Planning 40 (1998) 159–166.
[28] N. Ole Nielsen, Management for Agroecosystem Health: The New Paradigm For
Agriculture, New Directions in Animal Production Systems, IDRC and Canadian
Society of Animal Science, Vancouver, 1998, pp. 1–7.
[29] C.A. Edwards, P. R Lal, R.H. Madden, et al. Sustainable agricultural systems, Soil
and Water Conservation Society, Ankeny, Iowa, USA, 1990, pp. 674–676.
[30] M.A. Altieri, C.I. Nicholls, Applying agroecological concepts to development of
ecologically based pest management systems, in: Professional Societies and
Ecologically Based Pest Management Systems, National Research Council,
Washington DC, 2000, pp. 14–19.
17
[31] W.C. Lowdermilk, Conquest of the land through seven thousand years,
Agriculture Information Bulletin No. 99 (1953) 1–30.
[32] US Natural Resources Conservation Service (NRCS), Fort Worth, TX. National
Conservation Practice Standard: Nutrient Management, 2006, p. 590.
[33] US Environmental Protection Agency (EPA), Washington, DC. Nutrient
Management, 2007.
[34] R. Lal, Soil management in the developing countries, Soil Science 165 (1)
(2000) 57–72.
[35] J.R. Cate, M.K. Iiinkle, Integrated Pest Management: The Path of a Paradigm,
National Audubon Society, Washington, DC, 1994, p. 40.
[36] M. Kogan, Integrated pest management: historical perspectives and
contemporary developments 43 (1998) 243–270.
[37] S. Wang, Information technology: toward the way to the sustainable
management of agroecosystem, Agriculture Network Information 8
(2005).
[38] W. Zhu, S. Wang, C.D. Caldwell, Agro-ecosystem service and its managerial
essence, Chinese Journal of Eco-Agriculture 18 (4) (2010) 889–896.
[39] S. Wang, Ecosystem services assessment and management, in: W. Lin (Ed.),
Ecology, Science Press, Beijing, China, 2007, 4,7,12.
[40] J. Zhang, W.M. Rao, Discussion on agroecosystem services and sustainable
utilization, Chinese Journal of Ecology 23 (4) (2004) 99–102.
[41] B. Smit, D. Waltner-Toews, D. Rapport, et al., Agro-ecosystem Health: Analysis
and Assessment, University of Guelph, Guelph, Canada, 1998.