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1.
We argue that to support agriculture–environmental policy decision making, stakeholders need ‘quantitative back‐of‐the‐envelope’ analysis that is timely and sufficiently accurate to make informed decisions. We apply this concept to the analysis of the supply of ecosystem services from agriculture. We present a spatially explicit production model and show how it can be used to derive the supply of ecosystem services in a region. This model shows that the supply of ecosystem services can be derived from the spatial distribution of opportunity cost of providing those services. We then show how this conceptual model can be used to develop a minimum‐data (MD) approach to the analysis of the supply of ecosystem services from agriculture that can be implemented with the kinds of secondary data that are available in most parts of the world. We apply the MD approach to simulate the supply of carbon that could be sequestered in agricultural soils in the dryland grain‐producing region of Montana. We find that the supply curve derived from the MD approach can approximate the supply curve obtained from a more elaborate model based on site‐specific data, and can do so with sufficient accuracy for policy analysis.  相似文献   

2.
The massive expansion of semi‐subsistence farming in the European Union after the Eastern enlargements poses a real challenge to rural development. The problems of semi‐subsistence farms are low cash incomes and incidence of poverty, sub‐optimal use of land and labour, a lack of capital and poor contribution to rural growth. However, they play an important welfare function in some rural areas in Europe; they manage more than 11 million ha of agricultural land and deliver ecosystem services. The Common Agricultural Policy will have to accommodate this now widespread production system, through existing or new policy packages. Particularly important is support for commercialisation to incentivise and smooth the transition to commercial agriculture, and agri‐environmental payments to compensate the semi‐subsistence farmers for the provision of ecosystem services.  相似文献   

3.
Achieving the Sustainable Development Goals (SDGs) in African agriculture requires a better understanding why high levels of poverty and resource degradation persist in African agriculture despite decades of policy interventions and development projects. In this article, we hypothesize that policies need to account for the key features of the semi‐subsistence crop–livestock systems (CLS) in the region to become effective. The semi‐subsistence CLS are characterized by a high degree of biophysical and economic heterogeneity and a complex, diversified production system involving a combination of subsistence and cash crops with livestock. We investigated the potential for interventions proposed by the Government of Kenya to meet the SDGs by 2030. The analysis uses an integrated modeling approach designed to deal with the key features of these systems. A strategy that stimulates rural development, increases farm size to a sustainable level, and reduces distortions and inefficiencies in input and output markets could lead to a sustainable development pathway and achieve the SDGs for rural households dependent on CLS.  相似文献   

4.
Understanding the co-occurrence of multiple ecosystem services within farming systems and how they are associated across space are relatively new topics. Quantifying ecosystem services and their interactions as dependent on cropland management can help to formulate a more effective and sustainable land use management system. However, current academic efforts and cropland management practices based on the perspective of ecosystem services bundles and tradeoffs remain limited, especially in developing countries. This paper aimed to integrate ecosystem services into cropland protection and functional zoning. Taking Cixi County in the Hangzhou Bay area, China, as the case study area, five typical ecosystem services (food supply, carbon sequestration, hydrological regulation, soil fertility and recreation potential) delivered by croplands and their correlations were quantitatively assessed. The results demonstrated a heterogeneous spatial pattern of multiple ecosystem services and diverse interactions between them, which depended on regional specific conditions and agricultural activities. Further, we adopted the framework of ecosystem services bundles as a planning tool to support the spatial strategy of cropland management. Cropland protection priority and functional zoning were determined by hotspot analysis and clustering algorithms, respectively. The croplands in Cixi were classified into three protection grades and a zoning scheme comprising four functional types with policy guidelines was proposed based on the spatial cluster results. The integrative approach used in this study is applicable to supplement the current cropland management actions by incorporating the perspective of ecosystem services tradeoff and bundles.  相似文献   

5.
Restoring disturbed and over-exploited ecosystems is an important part of mitigating human pressures on natural ecosystems. An ambitious ecological restoration program, the Grain for Green Program (GFGP), was launched in 1999 in China. We selected the Loess Plateau (LP) as a case study, and evaluated ecosystem changes between 2000 and 2012 using biophysical models, observation records, and literature data. It was observed that both the warming and wetting of climate and the ecological program promoted vegetation growth and biomass production (i.e., carbon sequestration). Overall ecosystem patterns were relatively stable; grassland, residential land, and forest increased in area, while farmland area decreased slightly. Increasing precipitation throughout the study period was related to fluctuations in soil retention and hydrological regulation. Vegetation restoration induced by climate variability and the ecological program played a significant role in soil retention enhancement, which also substantially reduced sediment load. The land-use conversion in ecological restoration program promoted soil carbon sequestration, but featured differences in conversion types and rainfall zones. The ecosystem changes recorded in the LP, which resulted from both the ecological program and climate variability, might be temporary improvements rather than fundamental ecosystem shifts. The success of this ecological restoration in the LP exemplifies the positive effects of environmental policies and the necessity of adopting an adaptive management approach. However, the current assessment was not comprehensive, as it involved only three dominant regulating services, and there were still trade-offs among multiple ecosystem services. Therefore, a deeper understanding of the interactions and trade-offs among ecosystem services is required to explore in the context of emerging climate change, so as to support environmental management that maximizes ecosystem benefits to human well-being.  相似文献   

6.
We examine the nature of the ‘feminization of agriculture’ in the semi‐subsistence, peasant production sector of southeastern Mexico, as associated with male labour out‐migration. Presenting findings from empirical work with smallholder producers, we discuss the impact of men's migration to the United States on women's participation in agriculture and gendered relations of agricultural production. In 2007, we conducted a survey of 155 semi‐subsistence, smallholder households in six ejidos. This survey was supplemented by ethnographic research in a single ejido. Our findings demonstrate the need to distinguish between farm labour and management in this sector, and the potentially significant (but focused) changes in the local relations of agricultural production wrought by gendered patterns of labour migration – specifically in tenure, land‐use decision‐making and the management of hired labour.  相似文献   

7.
Climatic and land use change are amongst the greatest global environmental pressures resulting from anthropogenic activities. Both significantly influence the provision of crucial ecosystem services, such as carbon sequestration, water flow regulation, and food and fibre production, at a variety of scales. The aim of this study is to provide spatially explicit information at a national level on climate and land use change impacts in order to assess changes in the provision of ecosystem services. This work provides a qualitative and quantitative analysis of the impacts on selected ecosystem services (carbon sequestration, food production and soil erosion) in the agricultural sector of the Czech Republic. This assessment shows that, historical land use trends and land use under projected climate scenarios display some shared spatial patterns. Specifically, these factors both lead to a significant decrease of arable land in the border fringes of the Czech Republic, which is to some extent replaced by grasslands, in turn affecting the provision of ecosystem services. Moreover, this assessment contributes to a useful method for integrating spatially explicit land use and climate change analysis that can be applied to other sectors or transition countries elsewhere.  相似文献   

8.
Carbon sequestered through increased forest biomass provides a low cost means to curb emissions and has become a major focus of New Zealand's Emissions Trading Scheme. We present a forest planning optimisation model where land use is governed by forest owners maximising the returns to both timber harvest and carbon sequestration. By varying carbon prices, we model efficient trade‐offs between the two forest activities along a modified production possibility frontier for four distinct wood supply regions in New Zealand. Results show that while more productive regions such as the Central North Island (CNI) and Northland have a greater capacity as a carbon sink, it is the less productive regions that have a comparative advantage in carbon sequestration in terms of a lower cost of wood production revenue foregone. However, moderate increases in carbon uptake can be achieved in the CNI at low opportunity cost by subtle changes in forestry management. The implication for policy‐makers is that initial increases in carbon sequestration will be achieved at the lowest cost to society by favouring high volume timber production in some productive woodland areas and/or by more carbon farming in less productive areas.  相似文献   

9.
[目的]协同推进粮食安全与碳中和目标是当下中国的核心议题,但粮食生产对生态碳汇的影响尚不明确,文章尝试梳理粮食生产影响生态碳汇的作用机理,并实证甄别粮食生产影响生态碳汇的净效应。[方法]构建粮食生产影响生态碳汇的分析框架,利用2000—2017年中国县域面板数据,采用双向固定效应模型进行实证检验。[结果]基准分析表明,粮食生产对生态碳汇总量具有显著正向影响。异质性分析表明,复种指数的适度提升有助于发挥粮食生产的碳汇效应;相较于西部和东北地区,东部和中部地区粮食生产的碳汇效应更大。[结论]应重视粮食生产的碳汇属性,通过耕作制度调整等手段加强土壤保护,挖掘粮食生产的碳汇潜力;优化陆地绿色植被空间布局,降低农地、林地和草地等不同绿色植被碳汇的潜在冲突;基于区域差异,制定具有区域针对性的粮食安全与碳中和协同行动方案。  相似文献   

10.
We use a non‐parametric approach to investigate the (inverse) relationship between farm productivity and farm size. A kernel regression is used on data of mixed cropping systems to study the determinants of production including different factors that have been identified in literature as missing variables in the testing of the inverse relationship such as soil quality, location and household heterogeneity. Household data on farm activities and crop production were gathered from 640 households in 2007 in two Northern provinces of Burundi. Our results do not reject the findings of an inverse relationship between farm size and productivity. However, we find that size returns vary substantially with farm size, that is, between 0.2 for the smallest farms and 0.8 for the largest farms. Other factors that significantly affect production include soil quality. Finally, we find a significant positive association between food security and farm size.  相似文献   

11.
We propose an approach to model the derived demand for crop varieties among semi‐subsistence farmers in a developing economy, and apply it to smallholder banana producers in Uganda. We model variety planting decisions as being composed of an extensive margin decision to grow a subset of locally available varieties (variety choice); and an intensive margin decision about the scale or extent of variety cultivation per farm (variety demand). We estimate variety demand equations using a more complete representation of the choice set upon which observed planting decisions are made. Computed elasticities of variety demand with respect to variety attributes indicate that the relative importance of consumption and production attributes varies by location and proximity to markets, from which we draw implications for the social and economic impact of crop improvement. The approach that we propose has broad appeal for analysing adoption decisions for modern or traditional varieties of both major and minor crops in developing countries.  相似文献   

12.
Farm couples' labor market responses are partly the discrete choice of entering the off‐farm labor market and partly the continuous choice of off‐farm working hours, given entry. Such a setting is interesting when examining the increasing occurrence of multiple job‐holdings among farmers in Western economies. Most existing analyses of off‐farm labor supply only model the decisions of the farmer, not the joint decisions of the farm couple. This article presents a framework for handling such interrelated discrete/continuous choices, involving also farm production and household consumption. The derived two‐equation sub‐model for husband/wife's censored labor responses is estimated from a 10‐year Norwegian panel data for 342 farms. The results agree to some extent with earlier studies, but are more informative because of the longer panels—which allows a more extensive examination of latent heterogeneity and behavioral persistence—because it provides cross‐effects in the spouses' labor supplies. The results show some interesting differences between how the independent variables influence the labor supply of operator and spouse. This is most evident for the cross‐effects of education, children, and wage rate. Overall, the results strongly support applying a panel‐censoring model that accounts for latent heterogeneity in this context.  相似文献   

13.
In much of rural Africa, high transaction costs limit farmers’ market participation and thus their potential for income growth. Transaction costs can affect not only whether a farmer sells product but also whether sales occur at the farm gate or at a market. If production behavior is related to a chosen sales location, then analysis of interventions can be improved by explicit consideration of the decision of where to sell. This article develops a double‐selection model that explains consumption and production decisions by semi‐subsistence farmers who first decide whether to be a seller and then whether to sell at the farm gate or at an off‐farm location before deciding on production and consumption. The study tests the validity of this dual‐criteria model against a single‐criterion model in which a grower first decides to be a seller and then decides production, consumption, and sales location simultaneously. The results suggest that the dual‐criteria model provides more information than the single‐criterion model using a sample of cassava producer in Benin.  相似文献   

14.
Under the Clean Development Mechanism (CDM) of the Kyoto Protocol, forest projects can receive returns for carbon sequestration via two crediting instruments: temporary or long‐term certified emission reductions (tCERs or lCERs). This study shows the effect of lCERs on the private owner’s forest rotation intervals decision and carbon credit generation in afforestation and reforestation projects. A credit verification mechanism with a harvest penalty implemented under the lCERs policy distorts the timber harvesting decision and the corresponding carbon credit supply. Two opposing incentives are created by the lCERs mechanism which leads to either longer or shorter rotations compared to the Faustmann rotation, depending on which incentive prevails. Our numerical results show that both lCERs and tCERs seem to have similar impacts on harvesting incentives, but the resulting carbon supply differs among the instruments owing to the credit verification mechanism. The tCERs carbon supply curve is monotonically increasing in the carbon price, while a lCERs carbon supply is non‐monotonic and may have a backward bending region over a range of carbon prices.  相似文献   

15.
Land consolidation has a long history, and it has currently become one of the most extensive and well-organized human activities in China. Agricultural land consolidation (ALC) will change land use patterns, vegetation coverage, as well as the physical and chemical properties of soil through a series of engineering and biological measures that in turn affect the soil conservation service of ecosystems. This paper analyzes the effects of ALC on soil conservation service in the Hilly Region of Southeast China based on the Revised Universal Soil Loss Equation (RUSLE). The main results were as follows: (1) ALC improved the soil conservation service of cultivated land; (2) variations in the soil conservation service were strongly related to rainfall, slope, area of newly converted cultivated land, earth volume of land leveling, earth volume of topsoil stripping and backfilling, reconstructed farm roads, newly built production roads, length of new irrigation systems, newly built drainage systems, number of new dams, and newly built revetments; (3) the newly established multiple regression models used in this paper could describe the relationship between the soil conservation service and significant impact factors. This study will help researchers to better understand the interactions between land management and ecosystem service provisioning as well as provide a scientific basis for policymakers as they put forward new land management policies.  相似文献   

16.
Following the abolition of the milk quota in 2008, farmers in Switzerland strongly increased the use of concentrate feed in milk production. Against this background, the Swiss government introduced the voluntary grassland‐based milk and meat (GMF) programme in 2014, which combines economic incentives with feeding restrictions to reduce the reliance on concentrate feed and increase the use of grass feed. We analyse the economic and ecological impacts of the GMF programme at the farm and at the sector level in the short‐ and long‐run. We use a difference‐in‐differences approach (ex‐post) and an agent‐based simulation model SWISSland (ex‐ante) to construct counterfactual states to evaluate the programme's impacts. We find that the GMF programme reduces the use of concentrate feed and increases the use of grass feed in Swiss milk production. Whereas the programme has a positive effect on economic indicators such as the farm income, we find no effect on ecological indicators such as the N surplus. Our analysis suggests that feeding restrictions on concentrate feed are not enough to achieve a reduction in the N surplus. Additional feeding restrictions on grassland are necessary. Furthermore, the GMF programme has a dampening effect on sectoral milk supply, and leads to a higher milk price.  相似文献   

17.
The objective of this study is to investigate the subjective determinants of farmers’ participation in output markets in five EU New Member States (NMS) characterised by large semi‐subsistence sectors. It employs quantile regression to model market participation reflecting the heterogeneity amongst farmers. The study also uses the Bayesian adaptive lasso to simultaneously select important covariates and estimate the corresponding quantile regression models. The empirical results show that only two variables affect all quantiles, while their effect varies across quantiles. Some of the remaining variables affect the share of output sold at the lower quantiles (i.e. for subsistence‐ and semi‐subsistence‐oriented farmers) only, whereas other variables are only significant at the upper quantiles (i.e. for more commercially oriented farms). Advisory services, and particularly agricultural business advice, and information and advice on markets and prices can facilitate the market participation of subsistence‐oriented farms.  相似文献   

18.
We apply a value chain approach to examine how blackberry producers in Ecuador can improve production and marketing practices to obtain more favorable prices. Results show that general upgrading actions are associated with improved producer prices, and specific activities, such as seeking information from reputable sources can lead to substantial welfare improvements. The paper goes beyond most value chain studies which treat participation in a ‘modern’ value chain as a discrete state. Ecuador's blackberry industry is evolving incrementally with no clearly discernible ‘modern’ market chains. Instead, producers incrementally make improvements in multiple dimensions. Relatively low‐cost practices, many of which do not imply substantial risk or investment, are associated with price improvements. Obstacles to participation in incremental value chain upgrading activities are not insurmountable. In particular, scale of production is not a limiting factor: small‐scale producers are not precluded from adopting improved practices and they do not suffer in terms of price received.  相似文献   

19.
This paper describes how political and economic transition has affected the system of agricultural production in Khorezm, Uzbekistan in terms of economic practices and relationships. Based on recent fieldwork, the paper argues that the local agricultural economy is a hybrid economy, where production for market, quasi‐market and subsistence merge into and co‐constitute one another. In order to keep the system going, and to make up for the uncertainties in the formal context of production, the relation between new private fermer and the peasant (dehkan) households is of particular importance. This relation resembles neo‐patrimonial patron–client relations, which are both personal and informal while also being based on formal, contractual relations. The relations are asymmetric and based on the limited and unevenly distributed resources. The division of power is unequal but not fixed, due to the ongoing transition of the economic system.  相似文献   

20.
In this article, we analyze the role of subsistence‐oriented agriculture in Russia in the 1990s. We start out by discussing the diverging economic effects of the growth of subsistence agriculture in Russia since the transition process started. The quantitative analysis of this sector's role is carried out by means of an applied computable general equilibrium (CGE) model applying a 1994 social accounting matrix (SAM) as base year data. The novelty of the article is to disaggregate primary agricultural production not by products but by farm types, which enables us to distinguish their institutional and economic characteristics. The model also explicitly differentiates between marketed and subsistence consumption or formal and informal marketing activities of agricultural producers. We simulate two ex post and two ex ante experiments. The results of the first backward‐looking experiment highlight that Russia's subsistence agriculture was an important buffer against further agricultural output declines during transition and, hence, against food insecurity. A simulation, which looks into the effects of a devaluation of the Russian ruble, shows that the financial crisis should have increased the relative competitiveness particularly of large‐scale crop farms versus small‐scale farms. Two forward‐looking experiments indicate that efficiency enhancing institutional change would benefit both large‐scale and small‐scale farms. However, within small‐scale agriculture, a shift from subsistence to commercial agriculture would take place.  相似文献   

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