<1> Accession Number 992400259 Author Rodrigues, L. H. A. Zimmermann, F. Institution Faculdade de Engenharia Agricola - FEAGRI, Universidade Estadual de Campinas - UNICAMP, Caixa Postal 6011, CEP 13083-970, Campinas, SP, Brazil. Editor Zazueta, F. S. Xin JianNong. Title A decision support system for an organic farm. Source 7th International Conference on Computers in Agriculture, Orlando, Florida, USA, 26-30 October, 1998. American Society of Agricultural Engineers (ASAE), St Joseph, USA: 1998. 1-9. 8 ref. Abstract Protection of the environment has become an important issue and nowadays farmers have greater responsibility to preserve the environment than ever. Organic agriculture might be one alternative to agricultural production because it does not damage the environment. However, it is important to consider competitiveness in a global economy environment and efficient production is a necessity. This is possible if an optimal production plan is found. An integrated decision support system for use on an organic farm was developed. It incorporates a Linear Programming model that represents the organic farm system and optimizes production. The model also finds the optimal schedule for the main operations throughout the year, according to farm conditions and market demands. The decision support system assists in the planning of effective management programs and can also be used to evaluate the impacts that some changes would cause to the whole system.

<2> Accession Number 981903095 Author Lehmann, B. Hafliger, M. Keusch, A. Thomi, H. P. Wolf, H. P. Institution Institut fur Agrarwirtschaft, Gruppe Betriebswirtschaft und Okonomie des landlichen Raumes, ETH Zurich, CH-8092 Zurich, Switzerland. Title Nitrogen emission reduction and social costs. [German] Original Title Stickstoffenmissionsreduktion und volkswirtschaftliche kosten Source Agrarforschung. 1997. 4: 5, 205-208. Abstract Thirty-eight per cent of the environmentally harmful nitrogen emissions in Switzerland are caused by agriculture. The environmental condition was estimated by analysing the ecological performance of a sample of 228 farms. The data were aggregated in order to estimate the total output of harmful nitrogen compositions caused by Swiss agriculture. Regression analysis was used to determine the structural factors which have an influence on the amount of nitrogen released to the environment. The method of linear programming was used to estimate the reduction in the use of natural and synthetic nitrogen fertilizers and structural changes for certain farm types under future economical and political conditions. Using 'Agrarpolitik 2002' (agricultural policy 2002), which includes the introduction of Integrated Production or Organic Farming on all Swiss farms, a potential reduction of 28 000 to 32 000 t nitrogen released to the environment was estimated. Approximately 70% of this consists of ecologically harmful nitrogen compositions. The total social benefit (negative social costs) can be estimated at FS 22 500 for one ton of avoided nitrogen emission. <3> Accession Number 981903025 Author Kazenwadel, G. Zeddies, J. Lothe, K. Institution Institute of Farm Management, University of Hohenheim, D-70593 Stuttgart, Germany. Editor Jarvis, S. C. Pain, B. F. Title Balancing greenhouse gases and reduction of emission in grassland farming systems. Source Gaseous nitrogen emissions from grasslands. CAB INTERNATIONAL, Wallingford, UK: 1997. 373-381. 8 ref. Abstract

One cause of the greenhouse effect is the emission of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) into the atmosphere. Agriculture is particularly responsible for CH4 and N2O emissions, and is the main source of ammonia (NH3) emission. The costs of reducing nitrogen (N) leaching, NH3 and greenhouse gas emissions are addressed. The results can be used as a basis for assessing compensation payments for ecological performances in reducing greenhouse gases. The relationships between land use and environment are shown and optimized with the help of linear programming. Calculations are used to examine possibilities in existing farms. Different strategies to reduce NH3 and greenhouse gases are analysed. Several technical possibilities to reduce emission of greenhouse gases from grassland farming systems are shown. Measures to reduce the intensity of grassland use and to increase milk yields are particularly efficient and are, to some extent, profitable at the farm level. Under the defined conditions, covering manure stores, use of manure additives, manure injection and the installation of biogas plants are not economic at the farm scale. In order to introduce these measures, it would be necessary either to establish energy taxes or to grant subsidies for protection measures and for the use of renewable resources. However, agriculture could substantially contribute to reductions in environmental stress, particularly with respect to the greenhouse effect.

<5> Accession Number 971806788 Author Bazzani, G. M. Bradascio, M. Title Periurban agriculture in metropolitan areas: the Bologna case study. Source Working Paper - Center for International Food and Agricultural Policy, University of Minnesota. St Paul, Minnesota, USA: 1996. No. P96/4, 18 pp. 16 ref. Abstract A survey was undertaken to investigate the application of environmental measures in the northeast of the Emilia-Romagna area of Italy (EEC regulations no. 2078/92 and no. 2080/92). Data were collected from almost 100 farms (15% of the total) in the Bologna region by questionnaire and direct interview [no year given]. Linear programming models were used to study the main crops present in the area: grain, sugarbeet and potatoes. Farms were also modelled. Results to date are discussed.

<7> Accession Number 961808415 Author Hengsdijk, H. Ruben, R. Kruseman, G. Bakker, E. J. Quak, W. Sissoko, K. Institution Research Institute for Agrobiological and Soil Fertility Research (AB-DLO), P.O. Box 14, 6700 AA Wageningen, Netherlands. Editor Schoute, J. F. T. Finke, P. A. Veeneklaas, F. R. Wolfert, H. P. Title An integrated approach for analysis of sustainable land use. Source Scenario studies for the rural environment: selected and edited proceedings of the symposium Scenario Studies for the Rural Environment, Wageningen, the Netherlands, 12-15 September 1994. Kluwer Academic Publishers, Dordrecht, Netherlands: 1995. 623-626. 6 ref. Abstract A methodology to identify policy options for sustainable land use is presented using two types of models, each addressing specific questions. The approach is illustrated with a case study carried out in the Koutiala region of South Mali. A regional interactive multiple goal linear programming model (IMGLP) is used to explore limitations and potentials for agro-ecological sustainable agriculture in Koutiala under various regional objectives and constraints. The second model is a farm household model (FHM) that evaluates the effectiveness of various policy measures on land use and socioeconomic conditions on a particular farm type. Methods to link the results from both models are proposed. The results are tentative as both models are still under development, but they illustrate the type of information generated. Results of the IMGLP indicate that regional revenue can be raised by 80%. The production structure will shift towards more arable crops and less livestock. The results of the FHM show that a reduction in fertilizer price by 5% or the introduction of alternative technologies has almost no effect on net revenue per cultivated ha and production structure. The combination of the introduction of alternative technologies and the development of the rural financial markets seem to be more appropriate measures to introduce changes in land use. Major shifts occur in the number of animals and the C-balance. However, the C-balance is still negative indicating that farmers will still tend to deplete their natural resource base, although at a lower rate.

<8> Accession Number 961801760 Author Latesteijn, H. C. van. Institution Netherlands Scientific Council for Government Policy, P.O. Box 20004, 2500 EA The Hague, Netherlands. Editor Bouma, J. Kuyvenhoven, A. Bouman, B. A. M. Luyten, J. C. Zandstra, H. G. Title Scenarios for land use in Europe: agro-ecological options within socio-economic boundaries. Source Eco-regional approaches for sustainable land use and food production: proceedings of a symposium on eco- regional approaches in agricultural research, 12-16 December 1994, ISNAR, The Hague. Kluwer Academic Publishers, Dordrecht, Netherlands: 1995. 43-63. 11 ref. Abstract An eco-regional approach to research is called for to address emerging problems related to agricultural production and the environment. In agro-ecological analyses information can be gathered on constraints to and possibilities for agriculture in its physical and socioeconomic environment. Examples of application of this approach are still scarce. In this paper an example is demonstrated that deals with the methodology of exploring future possibilities for land-based agriculture in the European Union. To that end, future technical possibilities of primary production are confronted with a number of objectives relating to regional employment, pesticide and fertilizer use, and total costs. The technical possibilities are derived from regional production potentials of different indicator crops that have been assessed with the aid of a crop growth simulation model. In an interactive multiple goal linear programming model procedure, four scenarios of optimal land use are calculated, considering four distinct political priority settings (free market, current EU policy, nature/landscape conservation and environmental protection objective scenarios). Results of the study have been published in a report by the Netherlands Scientific Council for Government Policy, an independent advisory body to the Dutch Government. In a public debate following the publication of the report, several different groups discussed the usefulness of this type of analysis. The initial reaction to the study was somewhat reserved, because this type of exploration of the future gives rather different results than the more usual studies which rely on extrapolated trends. However, in the discussions that followed, the complementarity of both approaches has been accepted.

<9> Accession Number 961800583 Author Howitt, R. E. Title New methods for developing economic models to measure the interaction between agriculture and the environment. [Spanish] Original Title Nuevos metodos de modelizacion economica para medir la interaccion entre agricultura y medio ambiente Source Revista de Estudios Agro-Sociales.. 1994. 168: 2, 11-30. ref. Abstract The article first explains why economic models involving the interaction between agriculture and the environment differ in their requirements from models concerned exclusively with agricultural production. It then outlines the usual methods employed to measure this interaction, and shows their various drawbacks in terms of econometric approach and programming. An alternative method is proposed, which calculates more flexible production functions using a minimum data base, representing a compromise between linear programming and econometric forecasting systems. Finally, the characteristics of general equilibrium models are discussed, examining some initial applications to agricultural and environmental policy.

<10> Accession Number 921895705 Author Heijman, W. J. M. Institution Department of Farm Management, Wageningen Agricultural University, Wageningen, Netherlands. Editor Heijman, W.J.M. Krabbe, J.J. Title An economic evaluation of various governmental policies to reduce N-losses in dairy farming. Source Wageningse Economische Studies. 1992. No. 24, 169-184. 12 ref. Abstract Agriculture, and in particular animal husbandry, contributes substantially to Dutch environmental problems. Education and extension, financial stimulations like levies and subsidies, and legal regulations are the weapons that can be used by the government in addressing these problems. This paper qualifies the consequences of four government environmental policies on the labour income and the losses of nitrogen on dairy farms situated on sandy soil. Two policies impose a legal regulation and two impose a financial incentive to farmers. A linear programming model is used to model some typical dairy farms. The objective function of the model maximizes labour income of the farm (i.e., return to labour and management). The most important decision variables affecting nutrient use and nutrient losses are: the animal density on the farm, the feed ration of the cows and young stock, the method and length of storing manure, the method of applying manure to the land, whether the land is used for grassland or fodder crops, and the level of nitrogen application on grassland. The adaptations on the average farm that are the result of the policies lead to a decrease in farm income ranging from Dfl 2694 up to Dfl 8007. The effects of the policies on N-losses on the average farm show a decrease ranging from 5% up to 37%. Finally, it appears from the results that it is much more expensive to reduce ammonia emission than to reduce the same amount of other N-losses (leaching and run off).

<11> Accession Number 921895358 Author Eck, W. van. Title Environmental management on dairy farms in sandy areas - modeling economic effects. [Dutch] Original Title Natuurbeheer op melkveebedrijvenb in zandgebieden - Een modelonderzoek naar de economische effecten Source Onderzoekverslag - Landbouw-Economisch Instituut. The Hague, Netherlands: 1991. No. 86, 122pp. Price: Dfl 27.25. 23 ref. Abstract The study was executed in connection with the COAL project which examines the relationship between agriculture and the environment in the Netherlands. Linear programming was used to examine three management methods in relation to six kinds of dairy farms in sandy areas of the Netherlands. The three management methods consisted of edge, buffer and completely organic management. It is found that when protection of the environment is taken into account by farmers, productivity does suffer, especially where there is extensive farming. It is possible to pay farmers compensation but another sensible solution might be to give extra land to farmers, particularly when there is a labour surplus. This would decrease intensity of farming and help solve the excess manure problem.

<12> Accession Number 921894271 Author Vocke, G. F. Heady, E. O. Institution Economic Research Service, US Department of Agriculture, Washington, D.C., USA. Editor Heady, E.O. Vocke, G.F. Title Analysis of some environmental policies for American agriculture. Source Economic models of agricultural land conservation and environmental improvement. Iowa State University Press, Ames, Iowa, USA: 1992. 109-125. 7 ref. Abstract Using an interregional linear programming model, this study analyses a set of policies designed to alter current agricultural practices so as to reduce US agriculture's impact on the environment. Issues addressed are: the control of soil erosion; a policy restricting the use of nitrogen fertilizer; the restriction on use of certain organo-chlorine insecticides; and regulations requiring the control of runoff from livestock feedlots. Results indicate that all facets of an environmental improvement programme stand to have differing effects on US agriculture. The nation has sufficient producing capacity so that modest restraints on supply exercised through an environmental policy can allow domestic and export demands to be met without large increases in commodity supply prices. Since the USA is a large exporter of grains and cotton, supplies for domestic consumption are not endangered by any of the alternatives evaluated. Under each environmental alternative examined, some regions gain while others sacrifice in income and asset values. Regions that specialize in row crops, such as maize, cotton, and soyabeans, and that have sloping land and heavy rainfall would sacrifice under restraints on soil erosion and fertilizer use.

<13> Accession Number 911886113 Author Graaf, H. J. de. Tamminga, G. Title Production restraint in dairy farming - an exploration of its consequences for agriculture, nature and the environment. [Dutch] Original Title Produktiebeheersing in de melkveehouderij - verkenning van de gevolgen voor landbouw, natuur en milieu Source Onderzoekverslag - Landbouw-Economisch Instituut. The Hague, Netherlands: 1990. No. 70, 152pp. Price: Dfl 30.75. 33 ref. Abstract A study is made of the possible consequences of four policy variants which aim to control expenditure by the CAP. Attention is paid to the economic consequences for agriculture but also to the consequences for nature and the environment. The study was done with the aid of a regional linear programming model of Dutch agriculture plus a number of models. The results show that free trading within the milk quota improves the result for Dutch agriculture only slightly. Furthermore, in all variants on the policy model, prices in other branches of agriculture suffer. A quota system for milk production leads to the best consequences for the environment in all the regions.

<15> Accession Number 891867060 Author Tamminga, G. Institution Dutch Agricultural Economics Research Institute, Conradkade 175, The Hague, Netherlands. Editor Dubgaard, A. Nielsen, A.H. Title Integrating agriculture and the environment: a Dutch agricultural model. Source Economic aspects of environmental regulations in agriculture. Proceedings of the 18th Symposium of the European Association of Agricultural Economists (EAAE), November 1-4, 1988, Tune, Copenhagen, Denmark. Wissenschaftsverlag Vauk, Kiel, German Federal Republic: 1989. 257-266. 4 ref. Abstract The rapid growth of agricultural production in the Netherlands has led to a decline in environmental quality. The most serious effects are caused by intensive stock farming (excess fertilization and acidification). Due to a lack of political interest and a lack of knowledge, it is only recently that environmental problems have attracted more attention. A first step towards a better understanding of the relationship between agriculture and the environment on a national level, was a study on the possibilities of 'integrated agriculture'; an agriculture sector directed by both economic and environmental goals. Using a regionalized linear programming model of Dutch agriculture, a model is developed which proves helpful in analysing the relationship between agriculture and the environment. The model itself, utilization, shortcomings and advantages are described.

<16> Accession Number 891865191 Author Iaconoponi, L. Miele, S. Title Fertilizer applications in the context of stock and flows analysis of production processes. [Italian] Original Title

L'analisi 'fondi e flussi' del processo produttivo ed il caso della concimazione delle colture Source Rivista di Economia Agraria. 1988. 43: 3, 379-431. 28 ref. Abstract The neoclassical production function is re-examined in the light of criticisms from Georgescu- Roegen and of proposals put forward by Polidori and Romagnoli for a revision, particularly as regards its application in representing production processes in agriculture. The article examines in depth the economic consequences of the form of the fertilizer response function, of the relationship between the use of fertilizers and the environment and, finally, of the links between farm, cooperative, and industrial enterprises within an 'agro-industrial district'. Whilst bearing in mind that empirical and theoretical response functions may differ, the papers maintains that maximum yield and an economically optimum level of production coincide only when very restrictive partial equilibrium decision models are used. Taking into consideration product differentiation on the basis of quality, an evaluation of residual fertility and the cost of fertilizer dispersion in the environment, the economic optimum tends to move away from the technically maximum yield. The extension of the 'frontiers' of the agricultural production process from farm level to that of the agro-industrial district is dealt with by using a descriptive model in the form of a linear programming matrix where all possible economic and technical variables connected with fertilizer applications are included.

<17> Accession Number 891864432 Author Hanley, N. D. Title An economic analysis of agricultural externalities, with special reference to straw-burning. Source Index to Theses Accepted for Higher Degrees in the Universities of Great Britain and Ireland. 1988. 36: 4, p.1488. Abstract An economic analysis is made of the problem of agricultural externalities, (those side effects generated by farming which impinge upon the welfare of other members of society). The economic theory of externalities is examined, and particular attention is given to the efficient achievement of sub-optimal levels of externality. Policies seen as useful in achieving this goal include least-cost taxes and transferable discharge rights. Applications of this body of theory to problems of agricultural externalities are then considered. The thesis then examines the physical nature of the principal forms of agricultural externality, namely nitrate pollution, livestock wastes, pesticides, soil erosion and wildlife and landscape externalities. The legal and administrative situation in the UK is discussed, with attention given to the process of policy formation. Discussion then moves to how economists approach the valuation of environmental improvement, concerned as it is with non-market values. A contingent valuation study to estimate the benefits of a ban on straw- burning is presented. A linear programming model to estimate the costs of a ban on straw-burning in a variety of circumstances is then described. The model is then used to simulate alternative policy instruments being used to achieve a non-zero target level of straw-burning. It is demonstrated that a system of transferable discharge rights is capable of achieving this target efficiently. Finally, the costs and benefits (as estimated) of a ban on straw-burning are compared, and the conclusion reached that a ban is not Pareto- preferable. A 25% reduction in the level of burning would, however, yield net social benefits, given the assumed social welfare function. Conclusions are also drawn as to the usefulness of economic theory for problems of externalities, and as to the future of the agriculture/environment interface.

<20> Accession Number 851828907 Author Csaki, C. Harnos, Z. Institution K. Marx University of Economics, Budapest, Hungary. Editor Lechi, F. Title Methodology for the investigation of long term consequences of technological development in agriculture. Source Agriculture and the management of natural resources. Proceedings of the Eighth Symposium of the European Association of Agricultural Economists (EAAE), April 17-18, 1984, Milan, Italy. Kieler Wissenschaftsverlag Vauk, Kiel, German Federal Republic: 1985. 375-390. 8 ref. Abstract This paper outlines a methodology for investigating the relationships between agricultural production and the environment in Hungary. By taking into account the genetic potential of individual crops, habitat conditions and agricultural technology, a simulation model is developed which indicates possible changes in crop production/output and the environment. The long term relationships of agricultural land use are then described, using a crop production model based on linear programming.

<22> Accession Number 801957276 Author Vocke, G. F. Heady, E. O. Boggess, W. G. Stockdale, H. J. Institution Center for Agricultural and Rural Development, 578 East Hall, Iowa State University, Ames, Iowa 50011, USA. Title Economic impacts on U.S. agriculture from insecticide, fertilizer, soil loss and animal waste regulatory policies. Source CARD Report. 1977. No. 73, 94pp. 17 ref. Abstract The objective of this report is the analysis of policies designed to curb pollution problems created by excessive erosion of the soil, persistence of certain organo-chlorine insecticides in the environment, feedlot runoff, and the pollution of water supplies with nitrates. Various alternatives are analysed relative to stated levels of domestic and export demand by means of a linear programming model.

<23> Accession Number 801862249 Author Williams, R. J. Title A programming analysis of adjustments in agricultural production and resource use in Oklahoma, 1975 and 1985. Source Dissertation Abstracts International. 1978. 39: 4, p. 5060. Abstract The study presents a mathematical model of Oklahoma agriculture which is used to address a number of aggregate questions. One objective was to examine the current efficiency of Oklahoma's agricultural production pattern in order to identify opportunities to release strategic resources for other uses. Using the results of this objective as a base for comparison, a following objective was to evaluate the impact of changing (1) demand requirements, (2) productivity, (3) relative input costs, and (4) resource availability on the least-cost configuration of Oklahoma's production in a projected period. Three extensions of the latter objective were analyzed. In these extensions, energy prices or water availability restraints were changed to determine their effects on projected 1985 production and land use. The study includes two other major efforts which were used to facilitate the above analyses. An improved economic land classification system was developed to indicate differing productivity on various qualities of land. A "matrix generator" was developed which consists of computer routines which organized pertinent crop and livestock coefficients and processed these coefficients to facilitate their generation into the format required by an appropriate linear programming algorithm. Results indicate that Oklahoma agriculture is sufficiently versatile to react to marked changes in the economic environment. Model estimates suggest that in doing so, there appear to be opportunities to release critical land resources in the state for other productive purposes.

<26> Accession Number 781845151 Author Saygideger, O. Title Analysis of interaction between soil conservation and agricultural production in the United States using a multigoal linear programming model. Source Dissertation Abstracts International. 1978. 38: 7, p.4280. Abstract This study uses a multigoal linear programming model to quantify trade-off information between (a) the cost of producing US food supplies and (b) the maintenance of a more productive land base and a higher quality environment. In this model, the two goals of (a) production and transportation costs, and (b) soil erosion are minimized by combining them in a single objective function with the assignment of explicit weights for each goal. The weights assigned to the soil loss goal are interpreted as the pollution costs of soil erosion to society. Five alternative trade-off points on the trade-off curve are analyzed and compared in terms of the soil loss reduced and its contribution to environmental quality, the cost involved in reducing the soil loss and the implications of the conservation policies on the agricultural production systems. The study also analyzes alternatives in terms of their impacts on conservation and farming practices, land and other resources used in agriculture, soil loss levels, production patterns and farm incomes at the national and regional level. <27> Accession Number 781845070 Author Vocke, G. F. Title Economic and environmental impacts on U.S. agriculture from insecticide, fertilizer, soil loss, and animal waste regulatory policies. Source Dissertation Abstracts International. 1978. 38: 6, 3621-3622. Abstract This study analyzes national policies for US agriculture designed to curb pollution problems created by excessive erosion of the soil, persistence of certain organo-chlorine insecticides in the environment, feedlot runoff, and the pollution of water supplies with nitrates. The environmental policies are studied by means of an interregional linear programming model of US agriculture under projected production and demand conditions for the year 1985. The policies are studied in terms of their impacts on farming practices, land and water use, interregional shifts in crop and livestock production patterns, inputs used in agriculture, environmental impact, production costs, conservation practices and soil loss levels, export capabilities and other variables potentially affected by the imposition of environmental restrictions on the agricultural sector.

<28> Accession Number 771832880 Author Wade, J. C. Heady, E. O. Title A national model of sediment and water quality: various impacts on American agriculture. Source CARD Report, Center for Agricultural and Rural Development, Iowa State University. 1976. No.67, xx+199pp. 37 fig., 48 tab., 49 ref. Abstract

This study assesses the possible role of cropland agriculture in controlling the sediment loads of the streams of the continental United States. A linkage between agricultural production, land use, and stream sediment loads is developed. The soil loss from non-cropland use is assessed and total sediment loads are calculated in a simulated agricultural economy for the year 2000. A large-scale linear programming model of agricultural production is augmented with a stream sediment subsector. This model provides both completeness and flexibility in the agricultural sector for meeting problems of environmental stream water quality. To assess the workability of the model and to evaluate possible environmental policies, five alternatives are analyzed for stream sediment loads, agricultural land use, crop production patterns, and total social cost. The alternatives considered are possible policies that simulate a variety of environmental goals for the year 2000. Under the modelled linkage between cropland agriculture and stream sediment water quality, agriculture can be used to reduce sediment loads and meet environmental goals. The cost to agriculture and, thus to society, can be high for extreme environmental control. However, lesser control can be obtained at a small total cost through the reorganization of the production technologies and crops among and within various agricultural regions if comparative advantage relative to the model restraints can be reflected.

<29> Accession Number 751821815 Author Blyth, A. Rowbottom, J. D. Title Linear programming a representative farm. Source Farm Business Outlook. Edinburgh, UK: 1975. 2, 1-10. Abstract Prior to UK entry into the EEC a number of model or 'representative' farms were constructed for the East of Scotland College of Agriculture area, with a view to assessing the possible effect at the individual farm level of joining the Community. This was particularly important for livestock farming when it was thought that headage and acreage payments would be withdrawn and that producers' returns would have to come from the market. The data for each particular 'farm' were arranged to allow a computer to be used to provide the optimum solution (maximum farm net margin) within the restrictions imposed by farm and finance, i.e. the cropping and stocking policy derived is such that any departure from this policy will lead to a reduction in total net margin from the farm. The various 'activities' and 'constraints' for each 'representative' farm are retained in a basic matrix and can be used with varying objective functions (net revenues). The model outlined in the paper is one of a series representing typical farms in the College area for which the technical standards are continually being developed and price data are being updated. The upland farm model was chosen for its topicality at the present time. Although the results do not provide blue prints for all small upland farms they give guidance for advice on individual farms where the aim is to maximize farm income where the physical environment, husbandry constraints etc. are broadly similar to those of the model farms. They also provide guidance as to when alterations in policy should be considered in response to changes in relative prices, costs and government subsidies.

<30> Accession Number 751817914 Author Odero-Ogwel, L. A. Institution Department of Agricultural Economics, University of Dar es Salaam, Tanzania. Title Economic planning for peasant agricultural development under risk constraints. Source Eastern Africa Journal of Rural Development. Kampala, Uganda: 1974. 7: 1/2, 61-76. 2 tab., 1 app., 18 ref. Abstract The presence of risk presents serious problems and hampers rational decision-making in peasant agriculture. These problems are aggravated by the fact that the planners' objective decision-making differs markedly from the usually subjective decision-making behaviour of the farmers. This paper attempts to offer some contribution to the search for solutions to these problems in the context of peasant agricultural development planning and specifically explores the extent to which realism existing in the peasant farming environment could be approximated if the risk factor was taken into account. Quadratic programming was applied to a sector of Kenya's peasant agriculture, Nyeri District, comprising some 43,000 peasant holdings and the results were mainly judged against those derived under perfect knowledge linear programming assumptions and where possible against the actual reported parameters and official planned targets. On the basis of income, production and employment (the last in the tea and coffee industries) it emerged that more realism would be introduced in planning when tolerable risk aversion was allowed. Comparing with linear programming, perfect knowledge and actual situations risk programming results not only showed increased agricultural productivity and output but also considerable security to peasant farmers in terms of "minimum" subsistence food and adequately diversified production. The food crop sector which with the exception of potato proved rather unresponsive even to the relatively low level of risk aversion allowed and remained basically at subsistence.

<31> Accession Number 741808515 Author Thornton, D. S. Title Agriculture in South East Ghana. Volume I. Summary report. Source Development Study, Department of Agricultural Economics and Management, University of Reading. Reading, UK: 1973. No.12, xxiii+196pp. Price: pounds-sterling 0.50. tab., fig., 12 app., ref. Abstract The programme of work began with a study of the production environment which included an investigation of farming activities, and limited investigations of the marketing framework within which producers operate. An array of possible improvements, ranging from the infrastructure to production methods was then considered. Certain aspects of the institutions in the Region and the possibilities of change were also examined. Finally, attention was given to the general requirements of the planning process and in particular to two specific elements in it, the need for a Research and Development Unit and the potential of linear programming as a tool in planning.

<32> Accession Number 731804530 Author Cembalo, A. Angelis, L. de. Title Analyses of the suitability of mechanization in peasant farms. [Italian] Original Title Analisi della convenienza della meccanizzazione in aziende contadine Source Centro di Specializzazione e Ricerche Economico-Agrarie per il Mezzogiorno, Universita di Napoli, Naples, Italy: 1972. 53pp. Abstract This study had a two-fold objective: (1) to determine the possible profitability of the purchase of machinery such as tractors or motor-cultivators by tenants or peasant farmers in a given environment in Southern Italy, and (2) to illustrate a method of analysis (linear programming) which is believed to be of considerable relevance for the solution of the problem. The assessment of profitability was formulated by comparing the maximum net incomes obtainable by farmers in various alternative situations (without machinery, with motor-cultivators etc.). The definition of the net incomes mentioned above was determined by the solution of linear programming models. From the results the following conclusions are obtained: (i) Within the present farm structure, the introduction of a motor-cultivator on an individual farm would lead to a modest increase in income, while the introduction of a tractor would cause a reduction in the former income. (ii) If the land and building resources of the farms where doubled in size, it would give raise to a moderate increase in income. (iii) Although the utilization of the machinery by two or three farms together, instead of by a single farm, would allow a distribution of fixed costs over a larger area, it does not constitute a suitable method for reaching a satisfactory level of farm income. The analysis indicated that an effective process for improving farmers' incomes in the area requires: (a) a radical reshaping of production techniques; (b) the introduction of new production alternatives; (c) the improvement of farm structures. If these conditions are not met, the introduction of new machinery represents one way of improving farmers' incomes to a limited extent, but does not constitute, by itself, a means of achieving a stable and efficient agriculture. Accession Number 951804781 Editor Albisu, L. M. Romero, C. Title Environmental and land use issues: an economic perspective. Proceedings of the 34th EAAE Seminar held in the Mediterranean Agronomic Institute of Zaragoza, Zaragoza, February 7-9, 1994, Spain. Source Wissenschaftsverlag Vauk Kiel KG, Kiel, Germany: 1995. 540 pp. ref. Abstract This book comprises a selection of the papers presented at the 34th Seminar of the European Association of Agricultural Economists held in Zaragoza, Spain, 1994. The Seminar was a follow-up to a series of EAAE seminars about the economic linkages between agricultural activities and environmental resources. Selected papers cover a wide range of topics such as: supply and appraisal of environmental goods/bads, property rights and regulations, the dilemma between market allocation and planning in the use of natural and agricultural resources, and mathematical programming models to integrate agriculture and the environment. Some papers stress methodologies and techniques to evaluate economic aspects related to the environment, while others concentrate on case studies dealing with specific country or regional problems. Papers are divided between four sections under the headings of: (i) theoretical and analytical issues; (ii) mathematical models; (iii) other empirical models; and (iv) case studies.