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1.
Agroforestry systems have been promoted as sustainable land-use systems for regions where shifting agriculture is the traditional predominant land-use. Although environmentally sustainable, agroforestry systems require investment to establish that may affect their economic sustainability. In the southern Yucatan Peninsula 47 agroforestry plots of two timber and 10 fruit tree species were established with 22 farmers in three communities covering two rainfall zones and five soil types. Some fruit trees had wide adaptability to different soil, rainfall and management conditions, e.g. Manilkara zapota; others were restricted to the best soil, rainfall management conditions, e.g. Persea americana. The Meliaceae timber trees responded little to rainfall and soil, but stem borer attack was markedly lower in less intensively managed systems. Level of system maintenance greatly affected costs, but also opportunities for intercropping and obtaining immediate income. All levels of managements had negative net present value (NPV) for the three-year establishment phase, but so does traditional maize production. Farmers preferred to inter-crop their agroforestry systems, but were often limited by site quality. Determining sustainable agroforestry options for farmers requires multiple decisions related to species adaptability to the site, farmer production objectives and farmer capacity to invest in different management strategies. One production technology did not fit all.  相似文献   

2.
The U.S. dairy industry is undergoing rapid structural change, evolving from a structure including many small farmers in the Upper Midwest and Northeast to one that includes very large farms in new production regions. Small farms are struggling to retain competitiveness via improved management and low‐input systems. Using data from USDA's Agricultural Resource Management Survey, we determine the extent of U.S. conventional and pasture‐based milk production during 2003–2007, and estimate net returns, scale efficiency, and technical efficiency associated with the systems across different operation sizes. We compare the financial performance of small conventional and pasture‐based producers with one another and with large‐scale producers. A stochastic production frontier is used to analyze performance over the period for conventional and pasture technologies identified using a binomial logit model. Large conventional farms generally outperformed smaller farms using most economic measures—technical efficiency, various profitability measures, and returns to scale.  相似文献   

3.
The aim of this study was to evaluate the relative economic profitability and net greenhouse gas (GHG) abatement potential of alternative tillage and cropping systems. A simulation model was parameterized using biophysical and economic data representing different crop rotations under conventional, minimum, and zero tillage cropping systems, in the Black soil zone of Saskatchewan. This model was used to estimate the relative potential of each of the management practices to sequester carbon and to emit GHG including, nitrous oxide and carbon dioxide. The model also provided estimates of the relative profitability of each of the management practices over time horizons of 30 years. These simulation results were used to develop trade-off functions reflecting net income and net GHG abatement for each cropping system. An income risk measure was incorporated to facilitate an analysis of the relative economic attractiveness of the simulated cropping systems. Furthermore, sensitivity analysis was performed on nitrous oxide emission coefficients (an area of significant uncertainty in the literature) and on weather patterns to reflect uncertain future climate change impacts. Results indicated that net GHG emissions were relatively lower for reduced tillage management, while conventional tillage may be relatively more attractive from an economic perspective. However, results also indicated that such economic factors as risk and economies of size may have a significant influence on this latter result.  相似文献   

4.
One of the main causes of tropical forest loss is conversion to agriculture, which is constantly increasing as a dominant land cover in the tropics. The loss of forests greatly affects biodiversity and ecosystem services. This paper assesses the economic return from increasing tree cover in agricultural landscapes in two tropical locations, West Java, Indonesia and eastern Bangladesh. Agroforestry systems are compared with subsistence seasonal food-crop-based agricultural systems. Data were collected through rapid rural appraisal, field observation, focus groups and semi-structured interviews of farm households. The inclusion of agroforestry tree crops in seasonal agriculture improved the systems’ overall economic performance (net present value), even when it reduced understorey crop production. However, seasonal agriculture has higher income per unit of land area used for crop cultivation compared with the tree establishment and development phase of agroforestry farms. Thus, there is a trade-off between short-term loss of agricultural income and longer-term economic gain from planting trees in farmland. For resource-poor farmers to implement this change, institutional support is needed to improve their knowledge and skills with this unfamiliar form of land management, sufficient capital for the initial investment, and an increase in the security of land tenure.  相似文献   

5.
Most industrial countries have experienced a transformation of land use: from decreasing to expanding forest areas, the so-called forest transition. Outside closed forests, European rural landscapes exhibit a diversity of tree-based agricultural systems, but the question of whether this forest transition has also affected ‘trees outside forests’ has rarely been studied. The aim of this study is to analyze the spatial-temporal dynamics of farm trees and woodlands in an agricultural landscape in Eastern Germany from 1964 to 2008, based on aerial photographs and digital orthophotos. Taking a landscape ecological perspective, we quantify farm tree dynamics, disentangle processes of gain and loss in the socialist and post-socialist periods of Eastern Germany, and assess differences in ecosystem services provided by farm trees. A substantial increase of overall tree cover by 24.8% was observed for the selected time period, but trajectories have been disparate across different farm tree classes. The increase in tree cover was stronger in steep valleys than on hills and plateaus, indicating a significant interdependence between topography and trajectories of change. Patch numbers of farm trees did not increase, which suggests that the expansion of tree cover is mostly due to a spatial expansion of previously existing tree patches. Overall net gains in tree cover were rather similar during the socialist and post-socialist eras. The general increase in tree cover was accompanied by increase in agriculture-related ecosystem service provision, but the increase in pollination and pest control services was much lower than that in water purification services. These findings present the first empirical evidence from an industrialized country that there is also an ongoing ‘forest transition’ outside closed forests. Potential, partially counteracting drivers of change during the socialist and post-socialist periods have mainly been related to farm policies and the environmental consciousness of land users and society as a whole.  相似文献   

6.
Tree‐based intercropping (TBI) integrates tree production within annual grain cropping. The system is widely used in tropical regions, but is not common in temperate regions. This study evaluates the annualized return from TBI systems in southern Ontario, Canada against annual grain crop production. The TBI systems include hybrid poplar, Norway spruce, and red oak. The annualized return for all TBI systems is less than for annual cropping using the base prices; however, when tree prices are high and grain prices low the hybrid poplar TBI system has a higher return than annual cropping. Grants for planting trees, technologies to reduce the cost of establishing and maintaining trees, and improving the returns from tree production will be required for producers in temperate regions to adopt TBI systems. Un système de cultures intercalaires (SCI) intègre la production d’arbres dans la culture annuelle de céréales. Ce système est largement utilisé dans les régions tropicales, mais peu courant dans les régions tempérées. La présente étude évalue le rendement annualisé des SCI dans le sud de l’Ontario, au Canada, par rapport à celui de la production annuelle de céréales. Les SCI intègrent le peuplier hybride, l’épinette de Norvège et le chêne rouge. Le rendement annualisé des SCI est inférieur à celui des cultures annuelles si l’on utilise les prix de référence. Toutefois, lorsque les prix des arbres sont élevés et que les prix des céréales sont faibles, le SCI qui intègre le peuplier hybride obtient un rendement supérieur à celui des cultures annuelles. Pour que les agriculteurs des régions tempérées adoptent les SCI, il faudra offrir des subventions à la plantation d’arbres, offrir des technologies qui permettront de réduire les coûts de plantation et d’entretien des arbres et améliorer les rendements/revenus de la production d’arbres.  相似文献   

7.
Cooperation among farmers is an effective alternative to reduce production costs in smallholdings of traditional olive groves and increase their low profitability. However, an increase in efficiency reduces working hours and the labour required for the management of farms. This fact can lead to negative effects in rural areas, especially considering the importance of the social aspect of the crop. Therefore, to contribute to the global discussion on the transition towards more sustainable farming, it is important to know, ex ante, what level of employment is generated by olive groves and what could be lost under more competitive and efficient scenarios. The purpose of the work is to quantify the expected impact on employment by the implementation of cooperative management methods in order to generate true and accurate information that can be used in the design of future policies that aim to increase the economic profitability of small olive farms. The results make clear that this way of managing farms, by increasing the efficiency of agricultural work, has a significant negative impact on employment. However, this management formula does encourage the professionalisation of the sector by generating quality employment, in addition to contributing to the preservation of small farms and the socio-cultural and territorial benefits they generate.  相似文献   

8.
Strategies encouraging the use of fewer agrochemicals while maintaining high yield are highly demanded for smallholder rice farmers. Intercropping helps to suppress pests and disease in upland farming systems. However, information on the role of intercropping in pest suppression and crop productivity in irrigated rice farming systems is sparse. To explore the possibility of establishing diversified agriculture management strategy that requires lower agrochemical inputs, a field study was conducted to evaluate the effect of rice and water spinach intercropping on the occurrence of pests, disease, and land-use efficiency. Results demonstrated that the occurrence of rice blast disease, sheath blight disease, and Cnaphalocrocis medinalis was substantially lower than pure stands. Compared with rice monoculture, the tiller number, net photosynthetic rate, and leaf chlorophyll content were significantly increased in rice at the edge rows adjacent to water spinach in intercropping. Intercropping increased the per unit area yield of rice without significant reduction in that of water spinach. Land equivalent ratio (LER) was 1.13, showing that intercropping was 13% more productive than rice monocropping. Net income for intercropping was 5.04 times higher than for rice monocropping. These findings suggest that rice and water spinach intercropping is a viable alternative for sustainable rice production with a small farming scale in southern China.  相似文献   

9.
The assessment of sustainability at farm level has been growing in popularity over the last few years. This article contributes to this line of research by building up composite indicators for different facets—social, economic, environmental, and global—of farm sustainability using a methodological approach that combines data envelopment analysis (DEA) and multicriteria decision making (MCDM) methods, and assigns common weights to each individual sustainability indicator. This approach is applied to a database of 163 farms located in the Campos County, a region belonging to the dry lands of the Spanish Northern Plateau, using 12 individual indicators of sustainability. Our findings show that both economic and environmental composite sustainability indicators are positively correlated, but that this is not the case for the social indicator. We also check the influence of a set of variables on farm sustainability using bootstrapping statistical techniques, and showing that increasing farm size, membership in agricultural cooperatives and farmers’ medium and upper agricultural‐specific technical education, all exert a significant positive influence on sustainability. These results provide clues for policy makers that intend to design sustainability‐increasing structural agricultural policies.  相似文献   

10.
目的 探究农业保险通过改变农户生产行为,进而影响农业固碳效果的作用路径。方法 文章基于20082019年中国30个省(市、自治区,不含港澳台和西藏)的种植业数据,构建有调节的并行多重中介效应模型,分析农业保险发展水平对农业净碳汇的作用机制。结果 (1)从总体来看,当前农业保险的发展抑制了农业固碳效果,具体表现为农业保险增加了农业碳排放,而对农业碳吸收没有显著影响;(2)农业保险对农业净碳汇的影响有两条路径,一是农业保险通过提升种植专业化水平促进农业净碳汇,二是农业保险通过促进农业技术进步抑制农业净碳汇,但环境规制会削弱农业技术进步对农业净碳汇的抑制作用;(3)在异质性分析中,西部农业保险发展的农业固碳效果要好于东部,中部农业保险发展对农业固碳效果没有显著影响。结论 (1)提高对专业化规模生产主体的农业保险保费补贴比例,以放大农业保险对农业净碳汇的促进作用;(2)设计绿色农业产品保险,引导农业生产者从事绿色农业生产经营,减少一般机械投入对农业净碳汇产生的负向影响;(3)提高农业保险政策与环境保护政策的配合程度,在发展农业保险的同时,加强农业环境保护政策的执行力度。  相似文献   

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