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1.
Agroecosystems cover vast areas of land worldwide and are known to have a large impact on the environment, yet these highly modified landscapes are rarely considered as candidates for landscape design. While intentionally-designed agricultural landscapes could serve many different functions, few resources exist for evaluating the design of these complex landscapes, particularly at the scale of the whole-farm. The objective of this paper is to introduce an evolving framework for evaluating the design of agroecosystems based on a critical review of the literature on landscape multifunctionality and agroecology. We consider how agroecosystems might be designed to incorporate additional functions while adhering to agroecology principles for managing the landscape. The framework includes an assessment tool for evaluating farm design based on the extent of fine-scale land use features and their specific functions, to consider the present state of the farm, to plan for future conditions, or to compare alternative futures for the design of the farm. We apply this framework to two farms in Vermont that are recognized locally as successful, multifunctional landscapes. The Intervale Center, an agricultural landscape located within the city limits, serves as an incubator for new farm startups and provides unique cultural functions that benefit the local community. Butterworks Farm, a private operation producing organic yogurt and other food products, achieves important ecological functions through an integrated crop-livestock system. These farms and many others in Vermont serve as models of a framework that integrates landscape multifunctionality and agroecology in the design of the landscape. In the discussion section, we draw from the literature and our work to propose a set of important themes that might be considered for future research.  相似文献   

2.
《Agricultural Systems》2005,86(2):190-206
Within the Research Network on Agro-ecosystems Munich (Forschungsverbund Agrarökosysteme München, FAM) strategies to approach optimal land use have been investigated since 1990 in terms of minimization of environmental impacts and maximization of profit from agricultural lands. The purpose of this paper is to analyze the interactions of the economic and ecological demands on agricultural land use with model calculations for the integrated farm section of the research station of the Research Network, Klostergut Scheyern in Bavaria, Germany, with a whole farm modeling approach.For this purpose the model system MODAM was used. MODAM simulates agricultural land use at farm level, calculates the economic returns and environmental impacts and runs farm optimizations with a linear programming tool. The integration of agri-environmental indicators in the model framework enables a multi-criteria optimization and the calculation of trade-offs. Optimization runs for the experimental farm show the complex interactions which occur when the farm considers environmental concerns in the objective function. Trade offs and abatement cost curves illustrate the relationship between agri-environmental indicators and economic returns of the farm. Here, soil erosion, nitrogen balance, global warming potential and gross energy input were implemented as agri-environmental indicators in MODAM.  相似文献   

3.
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   

4.
Farm-level modelling can be used to determine how farming systems and individual farm-management measures influence different sustainability indicators. Until now however, worker physical health and societal sustainability have been lacking in farm models. For this paper, we first selected attributes of physical health (working conditions) and societal sustainability (food safety, animal welfare and health, and landscape quality). Second, possible sustainability indicators for these attributes were identified, and those selected were included in an existing dairy farm LP-model that was subsequently used to analyse possible differences in societal sustainability within and between a conventional and organic dairy farming system. Results for physical health and societal sustainability were similar for conventional and organic dairy farming systems in the basis situation, as well as in the situation where additional management measures were applied to improve societal sustainability, but improved animal welfare did result in the organic system due to prescribed grazing, and due to assumed summer feeding in the conventional system. Results show that additional management measures considerably improved societal sustainability of the conventional as well as the organic system. LP-modelling appeared to be a suitable method for comparing farming systems and determining the effect of management measures on physical health and societal sustainability. The level of societal sustainability is determined mainly by applied management measures, and is related to the particular farming system in only a very limited way. This implies that societal sustainability is mainly dependent on the cost-effectiveness of management measures and on the attitude of the dairy farmer.  相似文献   

5.
Promotion of integrated aquaculture with agriculture, including crops and livestock (IAA-farming), requires consideration of both bio-physical and socio-economic contexts. The major factors influencing the adoption of IAA-farming by households at three sites in the Mekong delta were identified. Special attention was given to the multiple roles ponds play in IAA-farming systems. Information was collected through semi-structured interviews and discussions with focus groups and key individuals. Data were analyzed using multivariate factor analysis, analysis of variance or participatory ranking methods. Three major IAA-systems were identified: (1) low-input fish farming integrated with intensive fruit production (system 1), (2) medium-input fish farming integrated with less intensive fruit production (system 2), and (3) high-input fish farming integrated with less intensive fruit production (system 3). System 1 was commonly practised in a rural fruit-dominated area with fertile soils, while systems 2 and 3 were more evident in peri-urban rice-dominated areas with less fertile soils. In the study area, only 6% of poor farmers adopted IAA-farming, while this was 42% for intermediate and 60% for rich households. Richer farmers tended to intensify fish farming and seek a more commercial orientation. The major factors why farmers did not start aquaculture were the inappropriateness of technology, insufficient land holding or poor access to extension services, limited farm management, and through a fear of conflicts associated with pesticide use on crops. The main motivations for practising IAA-farming included increased income and food for home consumption from the available farm resources while reducing environmental impacts. Further improvements to IAA-systems can be realized by strengthening nutrient recycling between different IAA-system components while enhancing farming output and safeguarding the environment.  相似文献   

6.
以景观生态学的“驱动因子－景观变化－生态影响”模型分析小水电开发带来的景观生态影响。在景观生态规划中，提出合理配置景观要素来优化小流域景观生态格局、结构和功能，修复受损河流生态系统。加强水电环境影响定量评价，并制定环境与生态恢复预案，预留足够的生态系统自我修复本底，保障河道环境与生态用水，重塑河流自然水文水力状态，挖掘其自我恢复能力。同时柔化处理自然基质、重新连接断裂河流廊道、恢复重建生物生境。  相似文献   

7.
The Livestock Gross Margin Insurance for Dairy Cattle is a federally reinsured insurance program that enables US dairy producers to establish minimum levels of milk income net of feed cost. Given the structure of this program there are an infinite number of possible contract designs based on the choice of deductible level and proportion of production insured. Adding to this complexity, producers vary in their risk preferences, which affect the incentive to insure their margin. It is unclear as to how producers may adopt this program for revenue risk management. This paper investigates the interplay between producer risk preferences, contract design and the subsidization of premium in determining program coverage. We undertook this analysis within an expected utility framework. Optimal contracts under different rates of constant relative rate of risk aversion and subsidies were analyzed using a nonlinear optimization model. We found that total optimal coverage increased significantly with the level of risk of aversion at lower deductibles but as deductible level increased, the level of risk aversion had a lesser impact on total optimal coverages. As expected, at the same deductible and risk aversion levels, inclusion of a premium subsidy increased the total optimal coverage.  相似文献   

8.
《Agricultural Systems》2004,82(2):139-160
Farm level modelling can be used to determine how farm management adjustments and environmental policy affect different sustainability indicators. In this paper indicators were included in a dairy farm LP (linear programming)-model to analyse the effects of environmental policy and management measures on economic and ecological sustainability on Dutch dairy farms. For analysing ecological sustainability, seven indicators were included in the model: eutrophication potential, nitrate concentration in groundwater, water use, acidification potential, global warming potential, terrestrial ecotoxicity, and aquatic ecotoxicity. Net farm income was included for measuring economic sustainability. The farm structure of “De Marke” formed the basis for three optimisations: (1) basis situation without environmental policy, (2) situation with Dutch environmental policy for 2004, and (3) situation with farm management measures applied at “De Marke”. The Dutch environmental policy was included to comply with the EC nitrate directive. It resulted in lower fertiliser use and consequently in a decrease in sales of maize. This led to a decrease in net farm income of ca. €2500. Including this policy improved most used ecological indicators (except for ecotoxicity) and showed to be an effective tool to reduce the environmental impact of dairy farming. Adapting the model with farm management measures applied at experimental farm “De Marke” resulted in even better ecological performance compared to the situation with environmental policy. Nonetheless this increase in ecological performance led to a considerably lower net farm income (€14,500).  相似文献   

9.
Improving water use and nitrogen efficiencies is of overall importance to society at large - to conserve scarce water resources and prevent environmental pollution. Efficient cultivation practices for rice which had no yield penalty were not adopted by farmers because of the open access to water free of charge. Well-chosen combinations of policy measures are thus needed to stimulate adoption of new cultivation practices. We developed a multi-objective linear programming (MGLP) model to explore the impact of: (i) modified rice cultivation including water-saving irrigation on farm profit; (ii) water pricing and water quota government policies on adoption of modified rice cultivation by farmers; (iii) a combination of (i) and (ii) to achieve the objectives of both farmers and society at large, and (iv) to study the trade-offs between income, water and nitrogen use. The analysis was carried out on four rice-based farm types for the state of Tamil Nadu, South India. Model results showed that observed farm profit of all four farm types could be increased using current practices simply by optimizing land use for specific crops. Adoption of modified rice cultivation further increased farm profit. Water-saving practices were selected only when water pricing was introduced. Farm profits were reduced even at low water prices but were compensated by farmers through adoption of modified rice cultivation. The combination of policies that stimulate adoption of modified rice cultivation was effective in achieving both increased farm income and water savings. The required water prices differed across farm types and seasons and impacted poor resource-endowed farmers the most. Providing water quotas could protect the poor resource-endowed farmers. The model helped to identify the optimal water price and water quota for each farm type to achieve both the objectives of farmers and society at large. Opportunities for reducing water use and avoiding environmental pollution at acceptable profits are available for all farm types, but need to be tailored to the farmers’ resource endowments.  相似文献   

10.
In trying to respond to societal demands for sustainable development, farming systems worldwide face a range of environmental, technical and economic challenges. These challenges call for renewed methodologies that can be used to support farmers in designing innovative agricultural production systems at the farm level. This paper aims to analyze the various methods described in scientific literature. The review is based on the analysis of 80 reference papers published in international scientific journals between 1999 and 2010. We focused in particular on the purpose of the research, which fell into two broad categories: “design” and “design support”. We also examined the use of models to represent production systems and to evaluate ex-ante the impact of innovations on these systems’ functioning and performance. In so doing, we developed a classification system to organize the studies into five sub-categories according to the type of methodology followed, namely: prototyping and design modelling for design orientated studies; participation, support modelling and advisory for design-support orientated studies. We found that very few studies attempt to address the three main components of an innovation process in agricultural production systems (biotechnical processes, farm management, and advisory services) within a single research framework. We therefore developed such a framework by connecting the design and design support orientations together with biotechnical research and conducting integrated research both at farm and advisory service levels.  相似文献   

11.
刘佳音  孟祥彬 《农业工程》2022,12(9):155-160
“十四五”时期是加快农业农村现代化发展的重要战略机遇期，我国农业正逐渐向多元化方向发展。将中国传统文化元素融入农业景观的设计想法日渐获得人们青睐，在农业景观中融入中国传统文化是促进农村经济发展、提高农业发展水平的新方式。基于以上背景，概括了农业景观的蓬勃发展、中国传统文化元素的内涵，以及两者相互融合而表现出的良好景观效果和实用性价值等内容，并浅析其不足之处，提出如何将传统文化融入到农业景观中及应遵循的原则，从而达到经济、适用、美观3者并存的高度。   相似文献   

12.
《Agricultural Systems》2005,85(1):82-97
Milk composition varies between herds and cows within herds, enabling its segregation on farm, rather than during processing, for the manufacture of specific dairy products. Benefits may include increased product yields, reduced processing costs and greater suitability of differentiated milk for the production of high value niche market products. However, costs are also likely to be greater. An integrated spreadsheet model was developed to determine the break-even premium required for a farmer with a seasonal calving herd to be economically no worse off producing segregated than conventional milk. The model incorporated breeding (quantitative and qualitative traits), cow requirements and feeding, transport, and economic sub-models. Cows were segregated within herd and milk composition was altered over time by genetic selection. Four quantitative trait (“white” milk colour) scenarios and two qualitative trait (BB β-lactoglobulin milk) scenarios were considered.The model suggested that “white” milkfat would need to earn 38.4% more at the farm gate than conventional milkfat for the two systems to break even. “White” milk cows produced less than their status quo counterparts due to the reduced selection pressure on production milk traits and this had a considerable impact on the premium, as did the low initial volumes of white milkfat. The difference in production between the B β-lactoglobulin cows and their status quo counterparts was less than for selection on white milkfat only. The high risk to farmers of discontinuing a differentiated milk policy could be moderated by changing the structure of premium payments over time. Hence, processing companies and farmers will need to work together to facilitate the uptake of milk segregation. This research model could be applied by dairy companies and farmers considering milk segregation policies.  相似文献   

13.
基于GIS和PCA降维的森林景观格局等级特征分析   总被引：1，自引：0，他引：1  
森林景观空间格局及其内在等级特征辨识是森林资源管理和生态环境规划的重要基础。以新疆天山北坡西段霍城林场为对象,以森林资源二类调查资料和DEM数据为基础,基于GIS和PCA降维方法,通过景观等级分类和景观指数分析,对林区森林景观空间格局及其等级特征进行了研究。结果表明:天山北坡森林景观格局存在明显的等级特征,在不同等级上森林景观破碎化严重,斑块大小空间变异强烈;随着森林景观等级细化,森林核心斑块大小、破碎化、景观丰富度、空间邻近程度等指标变异加强;在较高等级水平上,斑块密度(PD)、平均斑块面积(AREA_MN)、景观形状指数(LSI)、周长-面积分形维数(PAFRAC)等指数对概括森林景观空间格局具有决定性。森林景观资源保护和精细化管理应注重对景观破碎化、丰富度、斑块空间邻接度等指标的考虑及调控,进而为林区景观格局优化、森林景观资源健康经营与管理提供有力参考。  相似文献   

14.
景观破碎化与动态演变分析是景观生态学研究的核心之一。通过动态演变与景观破碎化分析,可在一定程度上揭示出湿地稳定性和人类干扰程度。根据凌河口保护区1988、1995、2000、2005、2009年五期湿地数据,通过土地动态度、斑块类型面积、斑块数、斑块密度、类型百分比、形状指数、分维数、分离度7个景观指标研究保护区的湿地空间变化特征及破碎化程度并进行造成湿地景观格局变化驱动力分析。研究结果表明,凌河口湿地景观的破碎化在1988年以前就很明显,1988～2009年呈现继续破碎化的趋势;而造成凌河口湿地格局演变的原因主要有自然和人为活动及社会经济的因素的影响,只有尽快建立凌河口湿地恢复对策,采取积极的保护措施,实现经济效益、社会效益和生态效益的统一。  相似文献   

15.
Groundwater in Spain, as in other arid and semiarid countries worldwide, has been widely used in the expansion of irrigated agriculture. In the Spanish Mancha Occidental aquifer, the excessive, and sometimes illegal, water abstraction for irrigation has promoted outstanding socioeconomic development in the area, but it has also resulted in exploitation of the aquifer and degradation of valuable wetlands. Water policies implemented in the region have not yet managed to restore the aquifer and face strong social opposition. This paper uses a multi-scale modeling approach to explore the environmental and socio-economic impacts of alternative water conservation measures at the farm and basin levels. It also analyzes their comparative cost-effectiveness to help policy makers identify the least costly policy option for achieving the goal of the Mancha Occidental aquifer's sustainability. To conduct this analysis, a Mathematical Programming Model has been developed to simulate: the closing-up and taxed-legalization of unlicensed wells, uniform volumetric and block-rate water prices, water quotas, and water markets. Aggregate results show that net social costs are not substantially different across policy option, so none of the considered policy options will be clearly more cost-effective than the others. However, there are significant differences between private and public costs (at the farm and sub-basin levels), which will be critical for determining the application in practice of these policies. Results show that controlling illegal water mining (through the legalization of unlicensed wells) is necessary, but is not sufficient to recover the aquifer. Rather, effective water management in this area will require the implementation of other water management policies as well. Among them, uniform volumetric and block-rate water pricing policies will entail the lowest net social cost, but will produce important income losses in the smallest and most water-intensive farms, which might put at risk the viability of these farms and the social acceptance of the policies. Further investigations on social costs, policy enforcement capacity and public participation in water management are highly recommended.  相似文献   

16.
《Agricultural Systems》2002,71(3):207-230
In a perspective of managing the evolution of the bocage landscape, we address the issue of the joint development of agriculture and landscape at micro-regional scales. The study aims at testing the hypothesis of a relationship between bocage structure and farm characteristics along a 10-km long gradient of decreasing density of hedgerows in Brittany (France). A sample of 69 farms is made from three study sites chosen along this gradient. Dairy production with maize, cereals and grassland predominate. Farm territories are scattered along the gradient. The production, economic levels, productivity and technical means increase from the dense to the open bocage area. There is a joint significant differentiation of the technical systems. Different levels of organization of the farming systems thus contribute to this pattern. The results suggest that the nature and organization of this joint diversity are key factors to evaluate and manage future developments.  相似文献   

17.
Nitrate leaching is one of the many forms of environmental pollution resulting from irrigation and intensive agriculture. In this work, a method of combining an agronomic simulation model (EPIC) and a mathematical multi-objective programming model is used to analyse the effects of three agricultural policies on farmer’s revenue and nitrate leaching. An evaluation of the net social costs associated with the different policy measures is also given. The farmer’s behaviour in different policy scenarios was studied in terms of selected crops, irrigation technique and method, and adopted management practices with focus on farm management practices and water application efficiency. Irrigation water pricing, subsidies to adopt improved management levels, and taxation on the use of nitrogen fertilizer were examined. A trade-off emerges between the levels of nitrate leaching and net farmer’s revenue more pronounced for nitrogen tax policies than for water pricing. The results obtained indicate that nitrate leaching can be reduced by about 40% with an associated net social cost of 269 €/ha for the water pricing policy, 183 €/ha for the tax on fertilizer and 95 €/ha for subsidies to high efficiency management.  相似文献   

18.
In face of climate change and other environmental challenges, one strategy for incremental improvement within existing farming systems is the inclusion of perennial forage shrubs. In Australian agricultural systems, this has the potential to deliver multiple benefits: increased whole-farm profitability and improved natural resource management. The profitability of shrubs was investigated using Model of an Integrated Dryland Agricultural System (MIDAS), a bio-economic model of a mixed crop/livestock farming system. The modelling indicated that including forage shrubs had the potential to increase farm profitability by an average of 24% for an optimal 10% of farm area used for shrubs under standard assumptions. The impact of shrubs on whole-farm profit accrues primarily through the provision of a predictable supply of ‘out-of-season’ feed, thereby reducing supplementary feed costs, and through deferment of use of other feed sources on the farm, allowing a higher stocking rate and improved animal production. The benefits for natural resource management and the environment include improved water use through summer-active, deep-rooted plants, and carbon storage. Forage shrubs also allow for the productive use of marginal soils. Finally, we discuss other, less obvious, benefits of shrubs such as potential benefits on livestock health. The principles revealed by the MIDAS modelling have wide application beyond the region, although these need to be adapted on farm and widely disseminated before potential contribution to Australian agriculture can be realized.  相似文献   

19.
African farming systems are highly heterogeneous: between agroecological and socioeconomic environments, in the wide variability in farmers’ resource endowments and in farm management. This means that single solutions (or ‘silver bullets’) for improving farm productivity do not exist. Yet to date few approaches to understand constraints and explore options for change have tackled the bewildering complexity of African farming systems. In this paper we describe the Nutrient Use in Animal and Cropping systems - Efficiencies and Scales (NUANCES) framework. NUANCES offers a structured approach to unravel and understand the complexity of African farming to identify what we term ‘best-fit’ technologies - technologies targeted to specific types of farmers and to specific niches within their farms. The NUANCES framework is not ‘just another computer model’! We combine the tools of systems analysis and experimentation, detailed field observations and surveys, incorporate expert knowledge (local knowledge and results of research), generate databases, and apply simulation models to analyse performance of farms, and the impacts of introducing new technologies. We have analysed and described complexity of farming systems, their external drivers and some of the mechanisms that result in (in)efficient use of scarce resources. Studying sites across sub-Saharan Africa has provided insights in the trajectories of change in farming systems in response to population growth, economic conditions and climate variability (cycles of drier and wetter years) and climate change. In regions where human population is dense and land scarce, farm typologies have proven useful to target technologies between farmers of different production objectives and resource endowment (notably in terms of land, labour and capacity for investment). In such regions we could categorise types of fields on the basis of their responsiveness to soil improving technologies along soil fertility gradients, relying on local indicators to differentiate those that may be managed through ‘maintenance fertilization’ from fields that are highly-responsive to fertilizers and fields that require rehabilitation before yields can improved. Where human population pressure on the land is less intense, farm and field types are harder to discern, without clear patterns. Nutrient cycling through livestock is in principle not efficient for increasing food production due to increased nutrient losses, but is attractive for farmers due to the multiple functions of livestock. We identified trade-offs between income generation, soil conservation and community agreements through optimising concurrent objectives at farm and village levels. These examples show that future analyses must focus at farm and farming system level and not at the level of individual fields to achieve appropriate targeting of technologies - both between locations and between farms at any given location. The approach for integrated assessment described here can be used ex ante to explore the potential of best-fit technologies and the ways they can be best combined at farm level. The dynamic and integrated nature of the framework allows the impact of changes in external drivers such as climate change or development policy to be analysed. Fundamental questions for integrated analysis relate to the site-specific knowledge and the simplification of processes required to integrate and move from one level to the next.  相似文献   

20.
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   

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