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1.
Kamel Louhichi Argyris Kanellopoulos Sander Janssen Guillermo Flichman Huib Hengsdijk Paul Berentsen Martin Van Ittersum 《Agricultural Systems》2010,103(8):585-597
The disciplinary nature of most existing farm models as well as the issue specific orientation of most of the studies in agricultural systems research are main reasons for the limited use and re-use of bio-economic modelling for the ex-ante integrated assessment of policy decisions. The objective of this article is to present a bio-economic farm model that is generic and re-usable for different bio-physical and socio-economic contexts, facilitating the linking of micro and macro analysis or to provide detailed analysis of farming systems in a specific region. Model use is illustrated in this paper with an analysis of the impacts of the CAP reform of 2003 for arable and livestock farms in a context of market liberalization. Results from the application of the model to representative farms in Flevoland (the Netherlands) and Midi-Pyrenees (France) shows that CAP reform 2003 under market liberalization will cause substantial substitution of root crops and durum wheat by vegetables and oilseed crops. Much of the set-aside area will be put into production intensifying the existing farming systems. Abolishment of the milk quota system will cause an increase of the average herd size. The average total gross margin of farm types in Flevoland decreases while the average total gross margin of farms in Midi-Pyrenees increases. The results show that the model can simulate arable and livestock farm types of two regions different from a bio-physical and socio-economic point of view and it can deal with a variety of policy instruments. The examples show that the model can be (re-)used as a basis for future research and as a comprehensive tool for future policy analysis. 相似文献
2.
Sandra Uthes Annette PiorrPeter Zander Jerzy BieńkowskiFabrizio Ungaro Tommy DalgaardMatthias Stolze Heidrun MoschitzChristian Schader Kathrin HappeAmanda Sahrbacher Martin DamgaardVerena Toussaint Claudia SattlerFranz-Josef Reinhardt Chris KjeldsenLeonardo Casini Klaus Müller 《Agricultural Systems》2011,104(2):110-121
The direct payment system of the Common Agricultural Policy (CAP) provides income transfers to European farmers. Recently, several countries including England and Sweden have advocated the elimination of direct payments after 2013. The extent to which an elimination of direct payments would affect the land use dynamics in Europe including impacts on structural change and the environment has not been addressed in the existing literature. In this paper, we combine participatory methods, to analyze regional preferences for functions and effects of agriculture, and farm-level modeling, to assess the impacts of such a policy change on farm structures and land use intensities in four European regions located in Germany, Denmark, Italy and Poland, each with different socio-economic and biophysical characteristics. In each region, the entire farm population consisting of different farm types with different production orientations and land management types was modeled under the presence and absence of direct payments using a combination of agent-based and bio-economic modeling. We found that the initial characteristics of the regions, such as the historical farm structure and regional site conditions, greatly influence the impact of direct support elimination and cause regionally different development trends. The results for the four regions were summarized in four specific storylines that emphasize how much the diversity of European regions matters for future policy decisions. An explicitly regional focus is, therefore, argued to be crucial to complement future policy analysis. 相似文献
3.
Pedro Le o de Sousa Luí s L. Silva Ricardo P. Serralheiro 《Agricultural Water Management》1999,40(2-3):341-351
Traditional irrigation systems still cover a large area of irrigated lands in Portugal. The needs for competitiveness leads to the gradual abandon of traditional systems, resulting in social and economic impacts. Pressurised on-farm irrigation systems provide labour savings but imply important investments. Surface irrigation does not require expensive equipment and is low energy and low labour consuming, if modern systems are implemented. Flexible-pipe, gated-pipe, surge-flow valve and cablegation are the main equipment issues available to Portuguese farmers for modern surface irrigation practice. Conditions for application of these systems have been studied relative to different soil and topographic conditions. Plane land, either horizontal or sloped and undulated fields can be irrigated by surface systems, if a convenient design is accomplished. The adequacy of the irrigation systems has been evaluated and a cost-benefit study was carried out. A case study of a situation with undulated land, representative of South Portugal, is presented in this paper, comparing surface irrigation issues and a sprinkler system. Conclusions show a particular economic interest on adopting surge-valve, gated-pipe and cablegation. 相似文献
4.
5.
The impacts of climate change on livestock and livestock systems in developing countries: A review of what we know and what we need to know 总被引：4，自引：0，他引：4
Despite the importance of livestock to poor people and the magnitude of the changes that are likely to befall livestock systems, the intersection of climate change and livestock in developing countries is a relatively neglected research area. Little is known about the interactions of climate and increasing climate variability with other drivers of change in livestock systems and in broader development trends. In many places in the tropics and subtropics, livestock systems are changing rapidly, and the spatial heterogeneity of household response to change may be very large. While opportunities may exist for some households to take advantage of more conducive rangeland and cropping conditions, for example, the changes projected will pose serious problems for many other households. We briefly review the literature on climate change impacts on livestock and livestock systems in developing countries, and identify some key knowledge and data gaps. We also list some of the broad researchable issues associated with how smallholders and pastoralists might respond to climate change. The agendas of research and development organisations may need adjustment if the needs of vulnerable livestock keepers in the coming decades are to be met effectively. 相似文献
6.
Hatem Belhouchette Kamel LouhichiOlivier Therond Ioanna MouratiadouJacques Wery Martin van IttersumGuillermo Flichman 《Agricultural Systems》2011,104(2):135-145
Bio-economic models can be used to assess the impact of policy and environmental measures through economic and environmental indicators. Focusing on agricultural systems, farmers’ decisions in terms of cropping systems and the associated crop management at field scale are essential in such studies. The objective of this paper is to present a study using a bio-economic model to assess the impact of the Nitrate Directive in the Midi-Pyrenees region (France) by analyzing, at the farm scale, farm income and three environmental indicators: nitrate leaching, erosion and water consumption. Two scenarios, the 2003 CAP reform (baseline scenario) and the Nitrate Directive (policy scenario), with a 2013 time horizon, were developed and compared for three representative arable farm types in the Midi-Pyrenees region. Different types of data characterizing the biophysical context in the region (soil, climate), the current cropping systems (rotation, crop management) and farm resources (irrigated land, labor) were collected to calibrate and run the models. Results showed that the implementation of the Nitrate Directive may not affect farm income. However, significant modifications to cropping systems and crop allocation to soil types were simulated. Contrary to expectations, nitrogen leaching at the farm scale did not change. Overall water consumption increased and soil erosion decreased due mainly to a modification in cropping patterns and management by soil type. This study provides an example of unanticipated effects of policy and trade-offs between environmental issues. 相似文献
7.
C. Bogahawatte 《Agricultural Systems》1984,14(4):199-212
In Sri Lanka cropping enterprises interact with livestock production on peasant farms. This analysis of the crop-livestock farming system aims at understanding the existing constraints and interactions between crops and livestock in these farms. The main objective of the study is to describe the crop-livestock integrated farming systems in three rainfed villages in the Moneragala district of Sri Lanka, and to evaluate these systems in terms of maximizing farm incomes from the different crop and livestock components of the systems. A field survey was conducted to collect data from 153 farming families for the Maha season of 1982/83. A linear programming model was formulated to test the hypothesis.The results show that in general the activities for lowland rice, highland rice, sugar cane, labour, farm cash cost, and MVP (compost) are higher in the optimal farm plan than in the actual farm situation. The livestock in the optimal plan is mainly confined to milch cattle. However, with the present high level of manutrition among rural livestock industry emphasis should be placed on the expansion of the rural livestock industry in the study villages. The optimal plan also suggests the use of crop residues as a substitute for compost for farm crops. Hence, in the context of escalating prices of chemical fertilizers, research is required to find the suitability of crop residues and household residues as substitutes for compost. Increases in supplementary irrigation may result in the expansion of the farm area and hence the farm income. Other methods of increasing farm income include: replacing hired labour with non-utilized family labour, increased agricultural research, and extension activity regarding the use of modern inputs by farmers on crops. 相似文献
8.
James KaufmanNicholas G. Kalaitzandonakes 《Agricultural Systems》2011,104(9):770-780
New low phytate crop varieties have been heralded for their potential to assist animal producers manage phosphorus (P) as both an input cost and as an environmental externality. This paper investigates the economic viability of such biotechnologies under regulations that attempt to minimize fecal P pollution by limiting land application of manure. Such restrictions often require animal feeding operations to spread manure over larger areas, thus increasing cost. To assess the economics of P mitigation, the production, handling, spreading, and vegetative uptake of manure nutrients for a variety of livestock growing operations was simulated. The simulation concludes that low phytate crops can be effective at mitigating P in situations where manure spreading geography is significantly restricted. However, alternative technologies such as phytase appear to offer a lower cost mechanism for mitigating P in most situations. 相似文献
9.
Shaun Lisson Neil MacLeod Jeff Corfield Lalu Wirajaswadi Syamsu Bahar Nasruddin Razak Dahlanuddin Sania Saenong Lia Hadiawati Lisa Brennan 《Agricultural Systems》2010,103(7):486-497
Bali cattle (Bos javanicus) account for about one quarter of the total cattle population in Indonesia and are particularly important in the smallholder farming enterprises of the eastern islands. The population of Bali cattle is declining in most areas of Eastern Indonesia because demand for beef cattle exceeds the local capacity to supply these animals. Indonesian agencies recognise that new strategies are required to improve the productivity of Bali cattle and to address major constraints relating to animal husbandry and nutrition. To date, the adoption of cattle improvement technologies has been historically slow in Indonesia, as is the case elsewhere.This paper reports on key findings from a long-term study conducted between 2001 and 2009 with smallholder households from six villages in South Sulawesi and Central Lombok, to develop and test an approach for evaluating and increasing the adoption of cattle and forage improvement technologies. The approach is based on the principles of farming systems and participatory research and involved four main steps; (1) benchmarking the current farming system; (2) identifying constraints to cattle production and strategies to address them; (3) desktop modelling of the production and economic impacts of selected strategies; and (4) on-farm testing of the most promising strategies with 30 participant smallholder households.The approach was found to be successful based on: (1) sustained adoption of a package of best-bet technologies by the 30 participating households; (2) evidence of positive production, social and economic impacts; and (3) significant diffusion of the cattle improvement technologies to other households in the project regions. 相似文献
10.
《Agricultural Systems》2001,68(3):215-232
There is still no pan-European assessment of the typology of low-intensity farming systems and of the changes which they are undergoing under current European Union (EU) farm policy. This study examines the variability of farm structure and farming practices of a typical cereal-sheep farming system under continental Mediterranean conditions with the aim of providing regional data of policy relevance. The collection of quantitative and qualitative data was planned with collaborative effort from regional extension agencies and followed the Delphi technique. Arable land in Castile-La Mancha occupied more than 70% of total agricultural land in 1997, the rest being natural pasture, shrub-steppe, and Mediterranean forest. Dry low-intensity arable systems still included a sizeable proportion of fallow to cropped land (20%) or somewhat more than 1,000,000 ha, and the winter cereal stubble was often grazed by sheep. These systems were of low intensity in the sense that they used low inputs per ha, particularly of nutrients and agrochemicals. They involved the exploitation of land, particularly for grazing, on an open and large scale. In this sense, they can also be considered extensive systems. On average, only 20% of arable farmers kept sheep, while 80% of the sheep producers were landless pastoralists. Young farmers tend to be disinclined to became involved in the sheep sector, because of the harsh working conditions of sheep farming operations. Response to new economic circumstances involved the evolution of traditional practices with corresponding lower use of farm labour. Although still low-intensive, these systems can be considered as modified forms of traditional practices which have responded to new technologies and the need to cut labour costs. The new objectives for agriculture in Castile-La Mancha, must create or maintain a way of life that is socially and economically attractive to young farmers, without the acceptance of environmentally damaging practices. These new objectives will require a new regionally-targeted EU aid scheme. In turn, there is a need to understand regional agriculture systems before we can hope to achieve successful policy. 相似文献
11.
Despite the fact that many smallholder farming systems in developing countries revolve around the interactions of crop and livestock enterprises, the modelling of these systems using combinations of detailed crop and livestock models is comparatively under-developed. A wide variety of separate crop and livestock models exists, but the nature of crop–livestock interactions, and their importance in smallholder farming systems, makes their integration difficult. Even where there is adequate understanding of the biophysical processes involved, integrated crop–livestock models may be constrained by lack of reliable data for calibration and validation. The construction from scratch of simulation models that meet the needs of one particular case is generally too costly to countenance. As for all modelling activity, the most efficient way to proceed depends on the nature of the systems under study and the precise questions that have to be addressed. We outline a framework for the integration of detailed biophysical crop and livestock simulation models. We highlight the need for minimum calibration and validation data sets, and conclude by listing various research problems that need attention. The application of robust and trustworthy crop–livestock models is critical for furthering the research agenda associated with animal agriculture in the tropics and subtropics. 相似文献
12.
Responding to changes in rural-urban linkages and government policies, bean (Phaseolus vulgaris L.) production systems in Costa Rica are undergoing transitions. Impacts of changes in bean production systems on environmental and economic sustainability were analysed at the field, farm and policy levels. A combination of interviews, agronomic surveys, on-farm experiments, and secondary information was used. Changes in agronomic and economic conditions over time were assessed by conducting agronomic surveys and experiments on farms representing a range of land-use intensities. Trade-offs between productivity and stability were quantified using Modified Stability Analysis. The adoption of land and agrochemical-intensive methods by resource-poor farmers cultivating steep lands resulted in decreased environmented and economic sustainability. Farmers with adequate resources were able to maintain economic viability by transferring land out of beans and into other commodities, particularly cattle. However, this shift in resource use decreased social equity by decreasing farm labour opportunities for smallholders and landless farmers and diminishing land available for tenants. These studies indicate that the impact of technology introduction on farming system sustainability can be assessed effectively by conducting integrated socioeconomic and agronomic analyses across farms representing various land-use practices and intensities. 相似文献
13.
In economic terms, resilience in farming has to do with the capacity of a farm business to survive various risks and other shocks. Despite its importance, resilience has seldom been directly considered in evaluations of economic sustainability. A whole-farm stochastic simulation model over a 6-year planning horizon was used to analyse organic and conventional cropping systems using a model of a representative farm in Eastern Norway. The relative economic sustainability of alternative systems under changing assumptions about future technology and price regimes was examined in terms of financial survival to the end of the planning period. The same alternatives were also compared in terms of stochastic efficiency. To model the risk of business failure adequately there is a need to deal with the risk of bankruptcy, and a modification of traditional analysis was used for that purpose. The organic farming system was found to be somewhat less economically sustainable than the conventional system, especially if the organic price premiums and the organic area payments were to be phased out. The results illustrate possible conflicts between pursuit of risk efficiency and economic sustainability. The model developed could be used to support farmers’ choices between farming systems as well as to help policy makers develop more sharply targeted policies. 相似文献
14.
Drawing on a study of two irrigation systems in Hebei Province, this paper documents the impacts of rural economic and organization reforms on irrigation system performance. In the two systems, prior to development of irrigation, farmers consumed all their grain within the household. However, at present both districts are selling grain, with annual output of 11.9 tons/hectare in Bayi and 8.5 tons/hectare in Nanyao. However, due to the use of groundwater in Bayi, output per unit of water is 1.5 kg/m3 in Bayi and 1.3 kg/m3 in Nanyao. In Bayi, farmers have augmented declining surface water supplies with groundwater and purchased water – using funds from sideline enterprises – and have increased output. In contrast, in Nanyao both income and grain output increases have reached a plateau. Nanyao, with its weak resource base, will probably need to develop additional income sources to be able to improve water management in order to reach the next plateau of productivity. 相似文献
15.
E.D. Cittadini M.T.M.H. Lubbers N. de Ridder H. van Keulen G.D.H. Claassen 《Agricultural Systems》2008
In South Patagonia, Argentina, sweet cherry is the main fruit-tree crop grown for export, resulting in a highly seasonal labour demand. Managers of deciduous perennial fruit orchards must consider both biological and economic relationships in selecting crop species and orchard design. This makes decisions at the farm-level extremely complex, as especially in such perennial crops, strategic (‘what to plant’, ‘with which technology’ and ‘how much area of each activity’, i.e. the final design) and tactical (‘when, what and how to plant in time’, the pathway to the planned farm) decisions have a long-term effect. The objective of this study was to explore the consequences of different strategic and tactical decisions at farm scale in fruit production systems of South Patagonia, considering the variation in interests and aims of different stakeholders, and using a sensitivity analysis to evaluate the consequences of possible changes in external conditions. A dynamic farm-scale optimization model called OPTIFROP was developed to generate alternative farm development plans, by allocating, in the course of the time horizon of the run, production activities to different land units, while optimising different objective functions, subject to several constraints. Although time-dependent, dynamic, mathematical programming models for analysing farming systems have been described in literature, the dynamic aspects of long-term decision-making in orchard design and their impact on the sequential (annual) nature of orchards in different growth phases (i.e. medium-term decision-making), need a higher time-staged dynamic approach with a staircase matrix structure. The model includes two objective functions at farm level: (1) maximization of the present value of cumulative financial result, which is the main objective for growers, and (2) maximization of cumulative farm labour, which is an objective often mentioned by policy makers. The inter-months deviation for labour demand (during the period of high labour demand, November–April) was included as an upper-bound. Input and output coefficients for the land use options considered in OPTIFROP were quantified using the Technical Coefficient Generator FRUPAT. Model results indicated that the present value of cumulative financial result and the cumulative farm labour are conflicting to a very limited extent. Timing and feasibility of implementing certain combinations of production technologies are affected by resource endowments and initial conditions, but these factors do not influence land use selection in the long term. Land use selection is driven by the objectives of the stakeholders. OPTIFROP showed that, through introduction of alternative crops, substantial reductions in labour peaks in the period November–April could be achieved with a relatively small reduction in farm income. The sensitivity of the model solution to the cherry price suggests that the fruit production sector of South Patagonia should pay more attention to the robustness of their land use plans and take preventive measures to avoid being caught by a possible crisis due to changes in the context. 相似文献
16.
农田地表径流氮素流失特性分析 总被引：1，自引：0，他引：1
为了了解不同的灌溉条件下水旱农田地表径流氮素流失特性,开展水旱作物节水与传统灌溉条件下农田地表径流氮素流失试验研究。结果表明,不同作物类型对氮素流失影响显著,旱地铵态氮质量浓度低于水田,而硝态氮则高于水田;灌溉方式对氮素流失有一定的影响,但并不显著。虽然节水灌溉农田地表径流氮素质量浓度较高,但由于排水总量大大减少,所以... 相似文献
17.
On-farm measurements and observations of water flow, water costs and irrigation labour inputs at the individual parcel level
were made in case studies of smallholder irrigation systems in sub-Saharan Africa and south-eastern Arabia. The systems, in
which the water source supplied either single or multiple users, were analysed to address the fundamental issues of labour
allocation for on-farm water management as this has important consequences for the success of such systems. Results show that
the costs associated with accessing water influenced labour input, because when they were low the farmers tended to increase
the irrigation rate and reduce the amount of time they spent distributing the water within their parcels. Conversely when
water costs were high, lower flow rates and more time spent in water distribution were observed, and this resulted in more
uniform irrigation and higher irrigation efficiency. Also, opportunities and demands for farmers to use their labour for activities
other than irrigation can lead them to modify operational or physical aspects of the system so that they can reduce the time
they spend distributing water within the parcels, particularly when the water is relatively cheap. Awareness and better understanding
of how farmers may allocate their labour for water management will lead to more effective planning, design and management
of smallholder irrigation systems. 相似文献
18.
M. Dingkuhn B.B. Singh B. Clerget J. Chantereau B. Sultan 《Agricultural Water Management》2006,80(1-3):241-261
Asia's Green Revolution of the 1960s and 1970s has largely bypassed West Africa, and “modern” (high-yielding, input responsive) germplasm for staple crops has found comparatively little adoption, except for systems that are have good access to markets and sufficient water resources. It is unlikely, however, that breeding objectives conserving traditional crop characteristics as found in extensive systems would have been more successful. The authors identify systems caught in the agricultural transition from subsistence to intensified, market-oriented production as the most important target for crop improvement, and provide examples of new breeding objectives for cowpea, sorghum and upland rice. In each of these cases, breeders, with the help of physiologists, have developed innovative plant-type concepts that combine improved yield potential and input responsiveness with specific traditional crop characteristics that remain essential during the agricultural transition. In the case of cowpea, dual-purpose varieties were developed that produce a good grain yield due to an erect plant habit, then produce new leaves enabling a second harvest of green foliage. For upland rice systems that are limited by labour (mainly needed to control weeds that abound due to shortened fallow periods), a weed competitive plant type was developed from Oryza sativa × Oryza glaberrima crosses. Lastly, sorghum breeders who had previously deselected photoperiod sensitivity are now re-inserting sensitivity into plants having “modern” architecture, in order to allow for flexible sowing dates while maintaining an agro-ecologically optimal time of flowering near the end of the wet season. The ecophysiological basis of these plant types, their place in current and future cropping systems, as well as the problem of under-funding for their realisation, are discussed. 相似文献
19.
This study uses a linear programming approach to compare the potential effectiveness of uniform rules (under the Integrated Pollution Prevention and Control Directive) and a landscape-scale (a scale that includes different land-uses) based policy for reducing ammonia (NH3) emissions and their related impacts from an operating case-study poultry installation. The model incorporates a variety of potential NH3 abatement techniques. It also incorporates the first application of a spatial model of the diffusion of environmental impacts from NH3 emissions. This models N deposition at a nearby nature reserve. 相似文献