LANDSCAPE ECOLOGY in AGROECOSYSTEMS MANAGEMENT - CHAPTER 12 pps

CHAPTER 12Models Assessing the Impact of Land-Use Change in Rural Areas on Development of Environmental Threats and Their Use for Agricultural Politics Armin Werner and Peter Zander CONT

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CHAPTER 12

Models Assessing the Impact of Land-Use Change in Rural Areas on Development of Environmental Threats and Their Use for Agricultural Politics

Armin Werner and Peter Zander

CONTENTS

Introduction and ObjectivesSustainable Development of Rural Land UseDecision Making for Solving Complex Problems of Rural AreasModels for Assessing the Impact of Land Use and Land-Use Changes Modeling the Development in Land Use

Assessing with Models the Impact of Land Use on the EnvironmentApproaches of Modeling Land Use and the Effects of Land Use Concepts for Landscape Models

Modeling Spatial AspectsApplying Models for Optimization of Land UseDecision Making for Land Use Planning in Rural Areas through Multi-Objective Optimization — An Example

The Multi-Optimization Model Simulations for the Study Area

An Outlook with Scenario Studies of Agricultural PoliticsPerspective

AcknowledgmentsReferences

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INTRODUCTION AND OBJECTIVES

Especially in industrialized nations, changing economic conditions lead to largestructural transformations in the businesses of land and its use (agriculture, forestry,in-land fish production, etc.) These transformations stem from changed politics ofland use resulting from the diminishing importance of the land-use business withinoverall business and from economic and possibly climatic global change Publicperception of land use is also changing More and more often not only is the supplyfunction (food, fiber, wood, etc.) addressed, but continuously increasing ecologicalgoals are proposed for land use and land-use planning The changes in these drivingforces will lead to changes in land use and thus in the impact of land-use systems

on rural areas (economy, social aspects) as well as on the ecology (abiotic sources,nature) Due to the complex interactions of land-use systems with the relevanteconomic, cultural and ecological indicators, it is necessary to address the resultingproblems of current or future land-use changes in an integrative way — integrated land development (Thöne, 2000) Integrated rural planning therefore can serve as

an example of methods and approaches that help to achieve a sustainable ment in human activities (Werner and Haberstock, 2001) The sustainable develop-ment of rural areas is a major goal of the national and international politics that arerelated to nonurban areas

develop-Most rural areas are dominated by agricultural land use Therefore, the impact

of agricultural land-use systems on the environment can be substantial Assessingthat impact on the environment is crucial for sustainable rural development But inorder to understand and control that impact and other relevant indicators, it isnecessary to develop new methods for assessing the impact of land use and tech-nologies and therefore of land-use politics or other relevant driving forces Thesemethods have to deliver general answers, that are scientifically sound and that can

be generalized but still are transferable to the specific conditions of the studied area.The cooperative character of studies on future land use requires expert knowledgeand innovative methods to analyze complex empirical data and to allow for theanalysis of possible futures

Many difficulties in the management of complex systems can be overcome withthe use of decision-making support systems This chapter summarizes and discussesmethods to assess the impact of changing land use with models An extensiveexample of the multi-criteria optimization approach shows the possibilities of usingsuch a system in decision making for economic-ecological problems in rural areas

SUSTAINABLE DEVELOPMENT OF RURAL LAND USE

Agrolandscapes are an integrated product of human actions, of agrotechnical,political, and ethical character (Mansvelt, 1997) Minor or drastic changes in land use,therefore, can always have implications for the entire complex system of an agrolan-dscape Consequently, it will be necessary to address and evaluate simultaneously

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several processes and values when the impact of technologies or agricultural politicshas to be assessed A common ground for defining a model for future land use isthe sustainable development of land use and thus of rural areas which is sustainable land development (Werner et al., 1997) Economic and ecologic, as well as socialand cultural, goals should be fulfilled (Barbier, 1987, Goodland, 1996).

With these goals in mind, integrative tools are necessary that support the sion-making process in rural areas and the related land-use planning (Maxwell et al.,1999) It is especially difficult to assess the impact of land-use systems on theenvironment of agrolandscapes (the complex of abiotic compartments and thenature) First, those indicators (values or objects) that should be addressed in theevaluation process are not yet sufficiently defined and agreed to (Maxwell et al.,1999) These indicators have to be selected by the affected stakeholders, the groupsthat participate in the decision-making process, or by society in general Whichindicators are suitable can be suggested by scientific evaluation through joint pro-cesses of different disciplines (Mansvelt, 1997) Second, it is necessary to havemethods for deriving the values these indicators will have under specific land-useconditions With this information, decision makers can select the feasible options inland use and landscape planning

deci-Many national or transnational (e.g., from the European Union) concepts related

to the development of rural areas have similar approaches (Bosshard, 2000) Theyinclude:

• Strengthening regional marketing and food processing

• Enhancing the competitiveness of regional business

• Improving the social or cultural activities within a region

• Attempting to close regional matter cycles

• Preventing pollution of abiotic compartments

• Protecting and developing sensible biotopes as regional habitats for typical species

The character of these elements represents remarkably the necessary ingredients ofthe general concept of a sustainable development (Thierstein and Walser, 1997) Forthe groups and people who participate in the planning and running of a region, thecommon base is the available space and the natural resources of that region Thereare no accepted and standardized methods available for defining all relevant groupsfor this participatory process of decision making and planning Even intuition can

be a crucial element of identifying the relevant stakeholders or actors (Baeriswyl

et al., 1999) Successful decision making for rural development needs a systematicprocedure and needs to be restricted to the relevant processes or compartments ofthe respective system, the rural area One approach is to identify the necessary andimportant functions that have to be fulfilled within the rural area For an integratedregion-oriented policy, Kolk et al (1999) identified 12 main categories of relevantfunctions of these landscapes: housing, utilities, agriculture, fisheries, industry, min-ing, services, retailing, transport, recreation, conservation and protection In manyregions this should be extended with the category of forestry For this chapter, thefocus is on agriculture, conservation, and protection

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of the area Today it is mainly a problem of communicating with the relevant people

or groups within the region and deciding how to let them participate in the making process: “Implementation of policy objectives and targets is not likely tohappen, without serious local participation and commitment” (Volker, 1997) Thisleads to the conclusion that integrated rural development is possible only with ademocratic approach, from the bottom up (Meyer, 1997) For this purpose, roundtables (Müller et al., 2000), environmental cooperatives (Glasbergen, 2000) andinnovation groups (Horlings et al., 1997) are relevant instruments to determine andmanage conflicting goals for the development of rural areas In terms of ecologicalgoals, recently the main focus of land-use development was on minimizing theimpact of agriculture and forestry on the abiotic compartments of the environment(water, soil, atmosphere) Today increasing attention is directed toward goals thatinclude, to a large extent, the living parts of agricultural landscapes (Harms et al.,1998)

decision-Rural areas have a good chance to achieve sustainable development when

• instead of being driven mainly by exogenous business processes, endogenous forces dominate

• the perspective of business and administration changes from sole consideration

of static-site factors to chance and possible developmental processes

• the perspectives in the region switch from economic forces to human action and initiative (Thierstein and Walser, 1997)

The last point in particular leads to the necessity of specific decision-making methodsfor rural areas These methods should help stakeholders define possible solutions orpathways in the development (scenarios) and analyze the outcome of these solutionswith respect to the views of all involved disciplines and groups (economy, ecol-ogy/nature conservation, social and cultural aspects) The process of defining objec-tives, assessing the impact of different land-use strategies, and eventually redefiningthose objectives will be repetitive and cyclic Decision making for the development

of rural land use has to be participative and iterative (Werner and Bork, 1998) Themost promising way to achieve all these goals is to jointly define scenarios andassess the impact on the economy and ecology with simulation models (Figure 12.1).This leads to a change in the paradigms of land-use planning and land developmentwith severe impacts on the related sciences, rural politics, consultation business, andregional or national administration (Magel, 2001)

However, one always has keep in mind that this recursive or heuristic approach

of assessing the impacts of land use cannot generate a “general truth” or “the onlybest solution” (Bosshard, 2000) The result of such decision making, or designing

of rural development and rural politics depends on the involved people and the actualscientific knowledge But “these results are independent of the existence of generally

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Evaluation and visualization

Geographic Information Systems

production farm income employment

Multiple Goal Linear Programming Farm model 1-r

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accepted moral axioms or principles” and therefore represent a nonauthoritativeapproach (Bosshard, 2000).

MODELS FOR ASSESSING THE IMPACT OF LAND USE

AND LAND-USE CHANGES Modeling the Development in Land Use

The specific situation of land use in a region is a result of the interactions ofsite conditions (natural productivity — i.e., soil, climate, water supply — type ofbusiness activities, infrastructure, etc.) and economic driving forces or conditions(politics, prices, assessable markets, environmental restrictions, available and per-mitted technologies, etc.) with the decision making of the land users Much literature

is available that describes procedures and models with which development of cultural and forestry land use can be determined under changing conditions Mostmodels were developed for analyzing the possible development of agricultural orforestry business sectors when prices, markets, technologies or other economicconditions change (Bouma et al., 1998) Recently, the predicted global changes ofclimate or economy are also the objective of the development of such models (e.g.,Mirschel et al., 1995) Most of these approaches are used to analyze the agriculturalbusiness Recently such sectoral models have been broadened stepwise toward addi-tional analysis of the impact of land use on environmental indicators (Wiborg, 1998)

agri-No integrated models are yet available to estimate or analyze the entire set ofdifferent functions of land use (see part 2 of this chapter) in a region at once Butsuch a holistic approach is necessary in order to answer questions related to thecomplex system of land development(Baumann, 1997; Buchecker, 1997; Ittersum

et al., 1998)

The impact of land use changes is the main focus for developing complexlandscape models These models provide scenario studies, describing the land-usesituation that can be expected in the future under a set of different conditions withdefined changes in the driving forces (Bork et al., 1995)

Assessing with Models the Impact of Land Use on the Environment

The environmental impact of land use can be analyzed in different ways Themain reason for doing this is to analyze different scenarios of land use Becausemost specific situations to be analyzed do not yet exist, it is not possible to useclassic scientific approaches of observing and measuring It therefore is necessary

to estimate or predict the relevant situations of land use with tools that are generaland that are capable of considering the specific situation of the region, its economicand environmental conditions Currently this kind of analysis can be accomplishedonly with specially designed and developed simulation models (Wenkel and Schultz,1999) These are computer-based tools that derive the conditions of relevant indi-cators with reasoning or calculations The main problems of designing and usingsuch tools lie in minimizing the amount of necessary input data and reducing the

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level of detail for the causal or indirect description of compartments or processes.Depending on the goals to be achieved, more or less sophisticated tools are devel-oped: simple approaches that balance relevant flows of matter, nutrients, or energy(e.g., Bach, 1987); models that consist mainly of conditional clauses, rules, or tablefunctions (e.g., Bork et al., 1995); models that describe the relevant processes indepth (e.g., Worral and Burt, 1999); or very complex models that look for a largeset of indicators in detail (e.g., O’Callaghan, 1995).

Models that should help to analyze the complex impact of land use on relevantecological indicators have a special demand for spatial data or they even have aspatial design (Costanza and Maxwell, 1991) because many ecologically relevantprocesses do occur as spatial interactions between compartments of a landscape(e.g., lateral flow of water, nutrients, matter, energy or migration of organisms) Butthe spatial interaction of business structures or human beings also has to be regardedwhen the whole landscape and its land use are analyzed (Bockstael, 1996, Wernerand Bork, 1998) To accomplish this goal, most landscape or land-use modelsdistinguish different processes in the landscape and describe relevant componentsseparately For the abiotic components, many models or sub-models exist for thelocal or the regional perspective (e.g., Addiscott and Mirza, 1998; Bass et al 1998;Dunn et al., 1996) Only a few models are available now that try to assess the impact

of land use on biotic components, species, or their habitats (e.g., Schultz andWieland, 1995; Lutze et al., 1999)

A crucial point in using complex land-use models is the availability of data thatdescribe the specific region in terms of the site conditions, the actual land-usestructure and the noncultural biotopes of a landscape (Briassoulis, 2001) Whenassessing the impact of land-use changes for a large area, in most cases only datawith a low level of spatial detail are available for site conditions, noncultural biotopes

or structure of the land-use business To collect data of actual land use, remotesensing can very easily provide a set of data that can cover completely the entireregion (Wadsworth and Downey, 1996) Other data, especially those for actualmanagement, are generally available with a high level of detail only for selectedfarms or other land-use businesses In most cases, only data sets without a detailedspatial resolution are available as statistical data for an entire region

Approaches of Modeling Land Use and the Effects of Land Use

After indicators to be addressed have been defined (Moxey et al., 1998), modelsare selected or developed that describe explicitly the processes or relate the values

of the indicators to the specific land-use situation (e.g., Johnes, 1996) All thesedifferent models should be linked either physically within a software-framework(Dunn et al., 1996, Lutze et al., 2000, Tufford et al., 1998) or run separately, exchang-ing data and information among single models (Wurbs et al., 1999)

Concepts for Landscape Models

With such simulation models, the analysis of landscapes will become an integralpart of designing sustainable land-use systems and supporting the decision-making

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processes for regions or rural areas (Belcher and Boehm, 1998) The differentconcepts for designing landscape models can, according to Lutze et al (2000), bedistinguished into two groups:

or algorithms; the entire model is developed in one set, and all parts must fit to each other from the internal logic and structure of the model as well as from the software development.

modules, which are linked by software calls; this approach allows different internal concepts for the submodels and even different programming languages.

Depending on the perspective on the landscape, it is possible to distinguish betweendifferent model types (Antrop, 2000) according to approach followed:

described with the model and can be analyzed with regard to the effects of land use.

that are described separately with the model and can be analyzed with regard to the effects of land use.

Modeling Spatial Aspects

Modeling the spatial aspects of interacting processes and driving forces is still

a challenge for landscape modeling In most cases, one-dimensional models (thedimension of time may always be added) are used to determine the impact ofdifferent land-use systems for defined points or homogeneous areas within thelandscape (e.g., Kersebaum et al., 1995; Priya and Shibasaki, 2001; Wegehenkel1999) These points or land units are selected from the entire landscape, so that(1) they are representative of a surrounding part of the landscape (in doing so,this piece of landscape is thought to be homologous for the relevant landscapeproperties; Verburg et al., 1999) or (2) sometimes the landscape is divided intocells of the same or different sizes, providing a full cover of the landscape with

a grid (for each grid cell the one-dimensional model will be calculated; Børgesen

et al., 2001) In both approaches, sometimes not all possible points or cells within

a landscape are simulated; only a selected number of typical combinations of sitesand land use are defined and simulated

Stepwise models are also developed that take lateral processes into account orare valid for a complete portion of the space in the landscape This modeling ismainly for water and matter flow (e.g., Ilyas and Effendy, 1996, Johnes and Heath-waite, 1997) Modeling biotic components and processes that are related to organ-isms requires spatial-explicit approaches Only a few models are available that dealwith lateral processes for the biocoenoses of landscapes (Lutze et al 1999).When developing landscape models with a spatial reference, it is necessary todefine on which level of spatial detail (scale) the landscape should be analyzed(Bockstael, 1996) Processes within the landscape that imply the same components

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(e.g., water-dynamic) can have different spatial pattern on different scales (Wenkeland Schultz, 1999).

Applying Models for Optimization of Land Use

In many cases of decision making for rural areas, it is necessary to providesuggestions that help find solutions for the specific problem In order to enhance agoal-oriented selection of land-use combinations or land-use systems, models areapplied with optimization procedures (e.g., Keith et al., 1999)

Zander and Kächele (1999) developed a complex model that allows estimation

of the situation of predefined farms within large regions under different economicconditions The model also includes estimations for ecological indicators for allpossible combinations of crop management With such an approach, simultaneouseconomic and ecological evaluations are possible With a given set of preferences,the best feasible combination of ecological objectives and economic constraints can

be found for a region (Meyer-Aurich et al., 1998)

DECISION MAKING FOR LAND-USE PLANNING IN RURAL AREAS THROUGH MULTI-OBJECTIVE OPTIMIZATION — AN EXAMPLE

Decision making in rural planning, as within other complex systems, requireshaving (1) different options, (2) sufficient information about these options, and(3) the power and other necessary resources to put a decision into action (Steffenand Born, 1987) Rural planning comprises agriculture, forestry, fishery, tourism,and infrastructure, among other areas Simulation and ecological optimization of themanagement of each of these sectors requires specific models Because agriculturedominates rural areas, assessing the impact of such land use is most relevant inanalyzing the environmental threats of changing land-use systems for rural areas.Modeling agricultural decision making under consideration of ecological objectives

is the focus of this section

The classical decision-making process in agricultural land use is related to mainlyone goal: maximizing the economic profit of the farm Often stability of income aswell as cash flow are defined as economic goals Introducing additional goals, such

as environmental objectives or those of nature protection, to the decision making ofthe agricultural business leads to a more complex situation It is then necessary tooptimize the activities and the production process toward more than a single goal(maximum economic output) Now selection of appropriate measures in land usemust be done with several goals in mind However, it is barely possible to maximizethe outcome of all objectives simultaneously In most cases, a compromise amongseveral objectives is the best possible solution, and only a few (if any) of the goalscan be fully realized; In order to find the best solutions, or compromises, a multi-objective optimization process is necessary (Alocilja and Ritchie 1990)

To support the decision makers whose goal is environmental protection (i.e.,abiotic- and biotic-oriented goals), it is necessary to supply them with land-use

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alternatives that can be considered in order to achieve the desired ecological goals.The decision makers on the production side need information about the effects thesedifferent land-use options have on the economy and the structure of the farms Therepresentatives for environmental protection in this decision-making process needinformation about the ecological impacts that would be caused by some specificoptions of the agricultural production systems Representatives of both the farmersand those for the environmental protection need to consider the best solution forboth sides.

The Multi-Optimization Model

The predefined cropping practices (Table 12.1) and their economic as well astheir ecological effects (Figure 12.2) are a partial evaluation information of the cropmanagement systems and the base for a complex simulation model (Figure 12.3)(Zander and Kächele, 1999) With this model one can find the most suitable com-bination of crop production systems for a given farm situation or region according

to predefined ecological and economic goals The search steps in MODAM areperformed through a farm model by optimizing total gross margin with ecologicalobjectives as restrictions (multi-objective-optimization) A series of consecutive runs

of the model is conducted In each run, the model is forced to use a 10% higherachievement rate for one specific environmental goal, going from the chosen refer-ence situation and to 100% in the achievement of the goal (Figures 12.4 and 12.5).The resulting relationships between the economic and the ecological variables arerepresented in trade-off functions

With the MODAM system several optimal economic-ecological solutions forgiven objective functions can be found It is also possible to analyze the impact of

Table 12.1 Priorities for Environmental Quality Goals Specific for Single Fields

(Principle Pattern, Examples)

Field-no

(example)

Goals Related to Single Species

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