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Agriculture, Ecosystems & Environment | 1999

A framework for integrated biophysical and economic land use analysis at different scales

B.A.M. Bouman; Hans G.P. Jansen; Rob Schipper; André Nieuwenhuyse; H. Hengsdijk; Johan Bouma

There is a general need for quantitative tools that can be used to support policy makers in regional rural development. Here, a framework for (sub-) regional land use analysis is presented that quantifies biophysical and economic sustainability trade-offs. The framework, called sustainable options for land use (SOLUS), was developed over a 10-year period of investigation in the Northern Atlantic Zone of Costa Rica and encompasses scale levels that range from field to region. SOLUS consists of technical coefficient generators to quantify inputs and outputs of production systems, a linear programming model that selects production systems by optimizing regional economic surplus, and a geographic information system. Biophysical and economic disciplines are integrated and various types of knowledge, ranging from empirical expert judgement to deterministic process models are synthesized in a systems-analytical manner. Economic sustainability indicators include economic surplus and labor employment, and biophysical ones include soil N, P and K balances, biocide use and its environmental impact, greenhouse gas emission and nitrogen leaching loss and volatilization. Land use scenarios can be implemented by varying properties of production inputs (e.g., prices), imposing sustainability restrictions in the optimization, and incorporating alternative production systems based on different technologies. Examples of application of SOLUS in the Northern Atlantic Zone of Costa Rica show that introduction of alternative technologies may result in situations that satisfy both economic as well as biophysical sustainability. On the other hand, negative trade-offs were found among different dimensions of biophysical sustainability themselves.


Ecological Modelling | 1998

Quantifying economic and biophysical sustainability trade-offs in land use exploration at the regional level: a case study for the Northern Atlantic Zone of Costa Rica

B.A.M. Bouman; Robert A. Schipper; A. Nieuwenhuyse; H. Hengsdijk; Hans G.P. Jansen

A generic methodology is presented for exploration of sustainable land use options at the regional level by quantifying trade-offs between socio-economic and biophysical sustainability objectives. The methodology is called SOLUS (Sustainable Options for Land USe), and was developed over a ten year period of investigation in the Northern Atlantic Zone of Costa Rica. SOLUS includes a linear programming model, technical coefficient generators for livestock and cropping activities and a geographic information system. The linear programming model maximizes regional economic surplus subject to a flexible number of resource and sustainability constraints. Economic sustainability indicators are economic surplus and labor employment, and biophysical ones include soil N, P and K balances, pesticide use and its environmental impact, nutrient losses and a proxy for trace gas emissions. The capabilities of the methodology are illustrated for the Northern Atlantic Zone of Costa Rica. Though ample scope exists for reducing environmental effects and introducing sustainable production systems separately, pursuing both objectives simultaneously, considerably reduces economic surplus and agricultural employment. Agricultural area can be decreased and forested area increased without severely affecting the regional economic surplus.


Agricultural Systems | 1999

Quantification of land use systems using technical coefficient generators: a case study for the Northern Atlantic zone of Costa Rica

H. Hengsdijk; B.A.M. Bouman; A Nieuwenhuyse; Hans G.P. Jansen

Abstract This paper describes two generic so-called technical coefficient generators, PASTOR (Pasture and Animal System Technical coefficient generatOR) and LUCTOR (Land Use Crop Technical coefficient generatOR), that quantify land use systems in terms of inputs and outputs based on the integration of systems-analytical knowledge, standard agronomic and animal husbandry data and expert knowledge. PASTOR quantifies livestock systems while LUCTOR is geared towards cropping systems. Main inputs quantified include costs, labour requirements, fertiliser use and application of crop protection agents. Outputs are production and a number of associated environmental indicators. Although both PASTOR and LUCTOR were developed to generate input data for land use models, they are also useful as stand-alone tools to explore the technical efficiency of land use systems, to perform cost-benefit analyses and to quantify the trade-off among socio-economic, agronomic and environmental indicators at the field level. PASTOR and LUCTOR are illustrated with data from the Northern Atlantic zone in Costa Rica. Tools such as PASTOR and LUCTOR integrate different types of knowledge, including non-documented knowledge from field experts and make that knowledge transparent and open to critical review and discussion by others.


Evolutionary Applications | 2011

Locus-dependent selection in crop-wild hybrids of lettuce under field conditions and its implication for GM crop development

Danny A. P. Hooftman; Andrew J. Flavell; Hans G.P. Jansen; Hans C. M. den Nijs; Naeem H. Syed; Anker P. Sørensen; Pablo Orozco-ter Wengel; Clemens C. M. van de Wiel

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter’s ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segregation patterns after hybridization between lettuce (Lactuca sativa) and its wild relative, L. serriola. Three generations of hybrids (S1, BC1, and BC1S1) were grown in habitats mimicking the wild parent’s habitat. As control, we harvested S1 seedlings grown under controlled conditions, providing very limited possibility for selection. We used 89 AFLP loci, as well as more recently developed dominant markers, 115 retrotransposon markers (SSAP), and 28 NBS loci linked to resistance genes. For many loci, allele frequencies were biased in plants exposed to natural field conditions, including over‐representation of crop alleles for various loci. Furthermore, Linkage disequilibrium was locally changed, allegedly by selection caused by the natural field conditions, providing ample opportunity for genetic hitchhiking. Our study indicates that when developing genetically modified crops, a judicious selection of insertion sites, based on knowledge of selective (dis)advantages of the surrounding crop genome under field conditions, could diminish transgene persistence.


Agricultural Systems | 1998

Quantification of aggregation bias in regional agricultural land use models: application to Guacimo county, Costa Rica

Hans G.P. Jansen; Jetse J. Stoorvogel

Different specifications of a land use model for Guacimo county in Costa Rica were used to quantify various sources of aggregation bias, including variation in farm resource endowments within and between representative farm classes; spatially variable prices; and labor market inter-dependencies between farm classes. The results indicate that adequate treatment of the farm level in regional land use analysis requires proper classification of individual farms in representative farm classes, as well as explicit modelling of inter-dependencies between such classes. Aggregation bias introduced by the assumption of spatially fixed farm-gate prices is insignificant for regions with reasonable infrastructure quality and relatively small distances between farms and markets. Aggregation bias caused by variation in resource endowments within farm classes cannot be eliminated, but should be minimized, underscoring the importance of a proper farm classification.


Tools for land use analysis on different scales: with case studies for Costa Rica | 2000

Integrated biophysical and socio-economic analysis of regional land use

Robert A. Schipper; B.A.M. Bouman; Hans G.P. Jansen; H. Hengsdijk; André Nieuwenhuyse

A methodology is presented with which regional land use options can be explored in order to provide policy support. This methodology is called SOLUS (Sustainable Options for Land USe) and integrates a linear programming model called REALM (Regional Economic and Agricultural Land-use Model) with Technical Coefficient Generators for crops (called LUCTOR) and for livestock activities (called PASTOR) used to quantify the technical coefficients of land use systems, and with a geographic information system (GIS). SOLUS is implemented for a case study in the northern Atlantic Zone of Costa Rica, with the objectives of i) analyzing regional land use practices while taking into account economic and environmental objectives and restrictions, and ii) evaluating economic and agrarian policies that influence the agricultural sector. Salient characteristics of the SOLUS methodology are the geographic explicit delineation of land and labor resources, the incorporation of endogenous prices of outputs and labor, and the variation of output prices according to quality of roads and distance to markets. The latter two aspects are related to the size of the region, while endogenous prices and wages are necessary because the supply originating in the region is capable of influencing prices and wages. Seven policy scenarios are studied that address policy and sustainability issues relevant to the region: technological change, zero soil nutrient depletion, limiting biocide use, taxing biocides, forest conservation, lowering interest rates and increasing real wages. It is shown that the SOLUS methodology is a suitable tool for the analysis of policy options in order to support policy decisions, as well as to analyze future land use options in view of their effects on income and the environment.


Fish & Shellfish Immunology | 2001

Integrated bioeconomic land-use models: an analysis of policy issues in the Atlantic zone of Costa Rica.

Robert A. Schipper; Hans G.P. Jansen; B.A.M. Bouman; H. Hengsdijk; André Nieuwenhuyse; Fernando Sáenz

1 Development Economics Group, Department of Economics and Management, Wageningen Agricultural University, Hollandseweg 1, 6706 KN Wageningen, The Netherlands 2 Research Program on Sustainability in Agriculture (REPOSA), Apartado 224, 7210 Guapiles, Costa Rica 3 Agricultural Economics Research Institute (LEI-Wageningen UR), P.O. Box 29703, 2502 LS The Hague, The Netherlands 4 DLO-Research Institute for Agrobiology and Soil Fertility, Wageningen, The Netherlands 5 International Rice Research Institute (IRRI), P.O. Box 3127, Makati Central Post Office (MCPO), 1271 Makati City, Philippines 6 Laboratory of Theoretical Production Ecology, Department of Crop Science, Wageningen Agricultural University, P.O. Box 430, 6700 AK Wageningen, The Netherlands 7 Centro International de Politica Economica para el Desarrollo Sostenible (CINPE), Universidad Nacional, Apartado 555-3000, Heredia, Costa Rica


Tools for land use analysis on different scales: with case studies for Costa Rica | 2000

Farm modeling for policy analysis on the farm and regional level

Peter Roebeling; Hans G.P. Jansen; Robert A. Schipper; Fernando S. Enz; Edmundo Castro; Ruerd Ruben; H. Hengsdijk; B.A.M. Bouman

The Atlantic Zone of Costa Rica accounts for nearly half of the total agricultural income in Costa Rica, and therefore is an important region for agricultural policy. Policy analysis can be performed on the regional level, using regional agricultural sector models that maximize regional welfare, as well as on the farm level, where different farm types are characterized by their specific objectives, production possibilities and resource endowments. While the former approach fails to model farm type-specific characteristics, the simple aggregation to the regional level of the representative farm type results ignores the interaction between the farm types that occurs in product and factor markets. The present study presents a regional equilibrium modeling approach that incorporates farm type characteristics as well as the equilibrium equations for product markets. Compared to a simple aggregation of representative partial results with exogenous output prices, the results produced by the regional equilibrium model indicate that the endogenization of product prices leads to lower levels of specialization in agricultural production, as well as lower incomes, profits and labor use. As such, the results obtained in a model with endogenous prices better reflect reality. A number of policy simulations are performed, including a 20% decrease in transaction costs, a 40% tax on biocide prices, and a 20% increase in credit availability. The former as well as the latter lead to increased cash crop production and corresponding increases in agricultural income, while taxing biocides leads to less biocide intensive cropping systems. The effectiveness of policy measures is, however, overestimated when product prices are assumed exogenous, since endogenously determined product prices limit specialization in the most profitable crops or in crops that require relatively low levels of biocides.


Agricultural Economics | 1992

Gini's coefficient of mean difference as a measure of adoption speed: theoretical issues and empirical evidence from India

Hans G.P. Jansen

This paper represents a variant on the empirical analysis of technological adoption by Griliches. It follows up on previous research regarding the potential of the Gini coefficient of mean difference as a distribution-free measure of adoption speed. A formal proof is supplied for the derivation of an empirically workable definition of the Gini. Data regarding the uptake of high-yielding wheat varieties in India are used to compare the performance of the Gini relative to that of the logistic and Weibull adoption speed coefficients. The results suggest that, for the purpose of ex-post analyses of monotonically increasing adoption processes, use of the Gini in measuring adoption speed can result in a better explanation of aggregate adoption behavior.


Economic Policy and Sustainable land use / Nico Heerink, Herman van Keulen en Marijke Kuiper | 2001

Alternative approaches to the economics on soil nutrient depletion in Costa Rica: exploratory, predictive and normative bio-economic models

Hans G.P. Jansen; Robert A. Schipper; Peter Roebeling; Erwin H. Bulte; H. Hengsdijk; B.A.M. Bouman; André Nieuwenhuyse

This chapter discusses three methodologies to analyse land use with respect to income generation and sustainability in the Atlantic Zone of Costa Rica: the explorative SOLUS methodology,the predictive UNA-DLV methodology,and a normative optimal control approach. Each methodology may be classified as bioeconomic; the first two are single period optimisation models at the regional and farm level,respectively,while the third is a dynamic model at the plot level. The SOLUS and UNA-DLV methodologies incorporate a multi-market structure for commodities produced by a wide spectrum of land use systems with specified technologies. For each of these systems,technical coefficients are generated related to discounted benefits and costs,and to sustainability indicators,including soil nutrient depletion. The optimal control model is confined to a pasture plot with cattle,property of a single farmer,and analyses the inter-temporal trade-off between soil nitrogen depletion and net benefits. Apart from assessing the ‘economic benefit - sustainability’ trade-off,all methodologies are capable of analysing the effects of technological change. After providing some example results,the chapter concludes with a comparison of the relative merits of each methodology.

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H. Hengsdijk

Wageningen University and Research Centre

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Robert A. Schipper

Wageningen University and Research Centre

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B.A.M. Bouman

International Rice Research Institute

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Erwin H. Bulte

Wageningen University and Research Centre

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John Pender

International Food Policy Research Institute

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Rob Schipper

Wageningen University and Research Centre

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Samuel Morley

International Food Policy Research Institute

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Valeria Pineiro

International Food Policy Research Institute

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