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1.
This paper considers the economy‐wide output and employment effects of the shift in forest expansion away from coniferous plantations towards broadleaf and native species. Four different woodland types are distinguished within a Scottish input‐output table and demand and supply multipliers estimated to show the total effects on the economy of a 100 hectare increase in the land area devoted to each type as well as a switch in land from agriculture. Results suggest that the output and employment effects of new native woodlands and farm woodlands are greater than those generated by planting additional coniferous woodlands of equivalent size. In addition, an increase in the area of these policy‐driven woodland types is likely to have positive effects, even when the expansion impinges onto agricultural land of average productivity. It is thus argued that the traditional economic objectives of forestry policy have not been compromised in the drive towards multi‐benefit woodlands.  相似文献   

2.
Ornamental plant sales have been identified as an important vector for the introduction of invasive plants. Increased concerns about the economic and ecological costs of invasive plants have spawned interest in identifying strategies to curtail introductions. One possible strategy is labeling plants based on whether they are invasive or native. The primary purpose of this paper was to explore how labeling plants based on invasive and native attributes might affect consumer demand. To accomplish this objective, a second price auction was used to elicit the willingness to pay (WTP) for plants with and without labels. On average, we found a $0.35 premium for plants labeled as noninvasive and native and a $1.01 to $1.66 discount for plants labeled as invasive. The size of these premiums and discounts differed in relation to various demographic, attitudinal, and preference‐related factors. Overall, our results suggest that labeling plants as invasive or native could be a viable strategy for reducing the introduction of invasive plants.  相似文献   

3.
Climatic change has a negative impact on people’s livelihoods, agriculture, freshwater supply and other natural resources that are important for human survival. Therefore, understanding how rural smallholder farmers perceive climate change, climate variability, and factors that influence their choices would facilitate a better understanding of how these farmers adapt to the negative impacts of climate change. A Zero-inflated double hurdle model was employed to estimate the factors influencing farmers’ adoption of adaptation strategies and intensity of adoption at the household level in South Africa. Different socioeconomic factors such as gender, age, and experience in crop farming, institutional factors like access to extension services, and access to climate change information significantly influenced the adoption of climate change adaptation strategies among beneficiaries of land reform in South Africa. Concerning intensity of adoption, age, educational level, farming experience, on-farm training, off-farm income, access to information through ICT and locational variables are the significant determinants of intensity of adaptation strategies. Thus, education attainment, non-farm employment, farming experience are significant incentives to enhance smallholder farmers' adaptive capacity through the adoption of many adaptation approaches. This study therefore concluded that farm-level policy efforts that aim to improve rural development should focus on farmers’ education, on-farm demonstration and non-farm employment opportunities that seek to engage the farmers, particularly during the off-cropping season. The income from non-farm employment can be plough-back into farm operations such as the adoption of soil and water conservation, use of improved planting varieties, insurance, among others to mitigate climate variability and subsequently increase productivity. Policies and investment strategies of the government should be geared towards supporting education, providing on-farm demonstration trainings, and disseminating information about climate change adaptation strategies, particularly for smallholder farmers in the country. Thus, the government, stakeholders, and donor agencies must provide capacity-building innovations around the agricultural extension system and education on climate change using information and communication technologies.  相似文献   

4.
Assessments of climate change impacts on agricultural markets and land‐use patterns rely on quantification of climate change impacts on the spatial patterns of land productivity. We supply a set of climate impact scenarios on agricultural land productivity derived from two climate models and two biophysical crop growth models to account for some of the uncertainty inherent in climate and impact models. Aggregation in space and time leads to information losses that can determine climate change impacts on agricultural markets and land‐use patterns because often aggregation is across steep gradients from low to high impacts or from increases to decreases. The four climate change impact scenarios supplied here were designed to represent the most significant impacts (high emission scenario only, assumed ineffectiveness of carbon dioxide fertilization on agricultural yields, no adjustments in management) but are consistent with the assumption that changes in agricultural practices are covered in the economic models. Globally, production of individual crops decrease by 10–38% under these climate change scenarios, with large uncertainties in spatial patterns that are determined by both the uncertainty in climate projections and the choice of impact model. This uncertainty in climate impact on crop productivity needs to be considered by economic assessments of climate change.  相似文献   

5.
The study was conducted to explore actual manifestations of climate change in smallholder cocoa farms to aid extension response to climate impacts, and to understand the reasons for a renewed interest in cocoa production in the forest-savanna agro ecological landscape in Ghana, in spite of unfavorable climatic conditions. Two hundred cocoa farmers were interviewed in nine cocoa farming communities. Selected farms were also visited to document on-farm manifestation of climate impacts as well as innovations and strategies farmers are employing to respond to the adverse impacts of climate change on their cocoa systems. The results revealed various manifestations of climate impacts on cocoa farms which included, increased incidence of pests and diseases, wilting of cocoa leaves, high mortality of cocoa seedlings which affected expansion and farm rehabilitation, and wilting of cherelles resulting in low yield. The farmers maintained that their response to the immediate impacts of climate on cocoa was a shift to cereals due to the unpredictable climatic patterns and the shortened duration of rainfall. However, a combination of storage and supply chain challenges and low returns from cereal production, coupled with land scarcity in the Western Region, where most of them are migrant farmers accounted for their decision to return to cocoa production lately. It was observed, among other adaptive responses, that some farmers plant about three times the plantain suckers they usually plant, to provide a dense temporary shade over cocoa seedlings, and resort to planting more cocoa seedlings randomly per unit area on new farms, contrary to recommended planting approach, as a form of insurance against seedling mortality. More importantly, a community-based fire response system was identified to be a major safeguard mechanism to the threat of fire. Clearly, the farmers are not replanting cocoa in the forest-savanna agro ecological landscape because it is more productive than cereals, but they believe that a low yielding cocoa is far better than a productive cereal cropping systems that offer low returns when compared to cocoa. The study brings out the sustainable livelihood challenges of the rural farmer within the context of a changing climate for appropriate policy response.  相似文献   

6.
Limited empirical evidence exists on how multiple binding constraints influence the adoption of improved technologies by smallholder farmers. This article uses the case of groundnut variety adoption in Uganda to investigate the role of information, seed supply, and credit constraints in conditioning technology uptake. New data from a household survey in seven groundnut growing districts (n = 945) indicate that 8% of farmers lack information on new varieties, while 18% and 6% of farmers, respectively, cannot adopt mainly due to seed supply and capital constraints. A tobit‐type specification that considers all nonadopters as being uninterested in the technology (i.e., corner solutions) would lead to inconsistent parameter estimates and incorrect conclusions in this context. We therefore estimate a modified multi‐hurdle specification of demand for new varieties, taking into account how information, seed supply, and capital constraints jointly determine adoption probability and intensity. The study reveals new empirical insights on why agricultural technology adoption in Africa has lagged behind: slow uptake is not mainly due to a lack of economic incentives, but rather a reflection of information, seed supply, and credit constraints that prevent farmers from translating their desired demand into adoption of modern varieties. Policy implications are discussed.  相似文献   

7.
New technologies must be developed in sub-Saharan Africa which are sustainable and economically viable. This paper discusses a methodology for measuring the agricultural sustainability and economic viability of tropical farming systems for new technology evaluation. The approach is based on the concept of interspatial and intertemporal total factor productivity, paying particular attention to valuation of natural resource stock and flows. Agriculture is a sector which utilizes natural resources (e.g. soil nutrients) and the stock and flows of these resources affect the production environment. However, in many cases, the stock of these resources is beyond the control of the farmer and must be accounted for in an agricultural sustainability and economic viability measurement. For example, soil nutrients are removed by crops, erosion or leaching beyond the crop root-zone, or other processes such as volatilization of nitrogen. Agricultural production can also contribute to the stock of some nutrients by leguminous plants such as agroforestry systems. Using a data set available at the International Institute of Tropical Agriculture, we compute the intertemporal and interspatial total factor productivity indices for four cropping systems in southwestern Nigeria using stock of major soil nutrients as the natural resource stock. Results show that the sustainability and economic viability measures are sensitive to changes in the stock and flow of soil nutrients as well as the material inputs and outputs. Where the contribution of natural resource stock and flows are important (such as in the case of alley cropping), the measures provide markedly different results from conventional TFP approaches. The advantage of this approach is that interspatial and intertemporal total factor productivity measures are computed using only price and quantity data, thus eliminating the need for econometric estimation.  相似文献   

8.
This review explores the role of land use and land use change as a determinant of the soil's ability to sequester and store carbon in the UK. Over 95 percent of the UK land carbon stock is located in soils which are subjected to a range of land uses and global changes. Land use change can result in rapid soil loss of carbon from peatlands, grasslands, plantation forest and native woodland. Soil carbon accumulates more slowly (decadal) but gains can be made when croplands are converted to grasslands, plantation forest or native woodland. The need for land for food production and renewable forms of energy could have considerable influence on UK soil carbon storage in the future. There is a need to recognise the risk of soil carbon losses occurring when land use change to increase carbon storage is offset by compensatory land use conversions elsewhere that result in net carbon release. The protection of peatland and other organic soil carbon stocks, and the management of cropland, grassland and forest soils to increase carbon sequestration, will be crucial to the maintenance of the UK carbon balance. It will be necessary to develop policy to balance trade-offs between soil carbon gains with other land use priorities. These include the sustainable production of food, bio-energy and fibre crops and livestock, water quality and hydrology, greenhouse gas emission control and waste management, all of which are underpinned by the soil.  相似文献   

9.
Pastoral landscape woody vegetation provides ecosystem services, but potentially competes for space, light and nutrients that could provide additional farm production. A questionnaire determined the values and behaviours of New Zealand dairy farmers to evaluate voluntary agri-environmental programmes for restoring woody vegetation. Findings indicate the area is increasing, while the composition and configuration of networks are changing and redistributing. Farms with little are losing more, and those with more are gaining. Farmers are planting new areas to increase their public ecosystem services, but may not provide these services through planting and management. Barriers include insufficient private woody vegetation ecosystem services, and low rates of growth of native plants. Government incentive programmes are ineffective in overcoming barriers. Farmers may be motivated by stronger evidence of valued ecosystem services, information about their benefits and drawbacks and how to support services through planting and management. However, a targeted environmental stewardship scheme is required to overcome barriers to planting, with government and the dairy industry working together to develop and maintain a landscape-scaled woody vegetation network on private and public land. Such networks would build sustainability and resilience into dairy farming, leading to an equitably sharing of benefits and costs of their public ecosystem services.  相似文献   

10.
The global land use implications of biofuel expansion have received considerable attention in the literature over the past decade. Model‐based estimates of the emissions from cropland expansion have been used to assess the environmental impacts of biofuel policies. And integrated assessment models have estimated the potential for biofuels to contribute to greenhouse gas (GHG) abatement over the coming century. All of these studies feature, explicitly or implicitly, competition between biofuel feed stocks and other land uses. However, the economic mechanisms governing this competition, as well as the contribution of biofuels to global land use change, have not received the close scrutiny that they deserve. The purpose of this article is to offer a deeper look at these factors. We begin with a comparative static analysis which assesses the impact of exogenously specified forecasts of biofuel expansion over the period: 2006–2035. Global land use change is decomposed according to the three key margins of economic response: extensive supply, intensive supply, and demand. Under the International Energy Agency's “New Policies” scenario, biofuels account for nearly one‐fifth of global land use change over the 2006–2035 period. The article also offers a comparative dynamic analysis which determines the optimal path for first and second generation biofuels over the course of the entire 21st century. In the absence of GHG regulation, the welfare‐maximizing path for global land use, in the face of 3% annual growth in oil prices, allocates 225 Mha to biofuel feed stocks by 2100, with the associated biofuels accounting for about 30% of global liquid fuel consumption. This area expansion is somewhat diminished by expected climate change impacts on agriculture, while it is significantly increased by an aggressive GHG emissions target and by advances in conversion efficiency of second generation biofuels.  相似文献   

11.
Integrating conservation and agricultural production is a major challenge globally. The upper Lachlan catchment of Australia is dominated by livestock grazing, and is threatened because most native woodland vegetation has been cleared. A third of all remaining tree cover occurs as scattered trees in grazing pastures. These scattered trees are dying from old age and are not regenerating due to grazing pressure. Previous work has revealed management strategies that are more likely to maintain tree cover, such as low-input rotational grazing. We asked graziers to photograph significant features on their properties, and used the images as prompts in later interviews. This elicited graziers’ landscape values and other drivers of their management practices related to tree cover. The targets that our 25 case landholders chose to photograph, and the ways they discussed them in later interviews, reflected the focus of past education and incentive programs, suggesting that well-designed policies, educational messages and incentives do seem to reach landholders and result in improved practices. For example, many landholders reported management activities related to the protection of large woodland patches or the maintenance of coarse woody debris. The maintenance of scattered tree cover has not been a focus of policy initiatives in the past. Despite this, the narratives elicited by photos of isolated and scattered trees showed graziers valued them and were aware of and concerned about their decline, yet lacked knowledge about how to protect and regenerate them. Graziers urgently need unambiguous advice and practical assistance to help them adapt their practices to maintain scattered trees in the long term.  相似文献   

12.
基于农业供给侧结构性改革背景的秸秆资源与利用研究   总被引:7,自引:0,他引:7  
[目的]分析农业供给侧结构性改革背景下我国秸秆资源产出与利用的变动趋势,就如何以农业供给侧结构性改革为契机促进我国秸秆资源利用提出对策与建议。[方法]利用试验数据检索和定量计算的方法,重点从种植业结构调整、现代种业创新、轮作休耕等任务着手,分析农业供给侧结构性改革对我国秸秆资源与利用产生的影响。[结果]以"镰刀弯"地区玉米结构调整为主要内容的种植业结构调整达到2020年规划期目标时,较2015年可减少玉米秸秆产出1 501万t,同时可为地区畜牧业发展提供青贮玉米等优质饲料、且玉米全株青贮通过养殖粪污得以过腹还田;若通过作物育种技术将水稻的经济系数提高0.03,可减少水稻秸秆产出1 360万t;实行耕地轮作休耕能够减少区域秸秆供应量,且随着轮作休耕试点面积的不断扩大,其减少秸秆产出的作用将持续增强。[结论]推进农业供给侧结构性改革,有望减少"无效秸秆"产出,减轻秸秆处置压力,促进秸秆综合利用,推动解决"小秸秆"带来的"大问题"。未来应在保证粮食安全的前提下,积极推进农业结构调整,转变发展方式,因地制宜调减"高产秸秆"作物改种"低产秸秆"或"零秸秆"作物;在充分发挥作物经济产量潜力的同时,通过积极培育和推广"低产秸秆"型作物品种、优化"低产秸秆"型高产栽培模式等途径控制作物秸秆产量。  相似文献   

13.
海洋渔业资源增殖放流效果的主要影响因素及对策研究   总被引:1,自引:0,他引:1  
渔业资源增殖放流的效果是渔业行政主管部门、渔业生产者和渔业科研单位共同关注的问题,也是增殖放流实践中的重要内容。基于国内外研究现状、多年海洋渔业资源增殖放流实践和水生生物增殖放流相关标准,对影响增殖放流效果的苗种质量、生态容纳量、放流策略、放流后期管理等4个主要因素进行了分析,探讨了各因素的影响程度、影响范围以及后果等问题,提出解决对策,指出在海洋渔业资源增殖放流实施过程中应该以理论指导实践,以实践验证理论,使我国增殖放流工作建立起科学的长效机制和一套完善的体系。  相似文献   

14.
中国天然橡胶安全问题的探讨   总被引:2,自引:1,他引:1  
对中国天然橡胶产量、消费量及进口量等在世界上所处状态及国内天然橡胶供需关系进行形势分析,发现中国天然橡胶安全日趋严峻,不利影响因素日益增多,将严重威胁到国家的经济安全。在此基础上,重点从天然橡胶安全的涵义及内容、影响因素、特征、指标体系等进行探讨,并据此提出应维持不少于30%的天然橡胶自给率、最低天然橡胶年库存量为50万t左右、天然橡胶外贸依存系数低于70%、天然橡胶消耗增长系数为100%左右等对策去应对的中国天然橡胶安全。  相似文献   

15.
Farmers’ risk preferences play an important role in agricultural production decisions. This study characterizes risk preferences among farmers in Yongqiao and determines how these risk preferences are related to their choices regarding climate change adaptation strategies. We find that most farmers in the study area were aware of climate change. They were taking measures to protect their livelihoods against perceived changes to the local climate. The risk experiment result shows that the representative subject was risk averse, and women were more risk averse than men. The relationships between farmers’ risk preferences and different climate change adaptation choices were different. Farmers’ risk aversion was negatively and significantly related with adaptation strategies on planting new crop varieties and adopting new technology, but it had a significantly positive effect on purchasing weather index crop insurance. The results also indicate that the level of education, farming experience, farm size, household income and perception of climate change impacts influence farmers’ adaptation decisions.  相似文献   

16.
食用植物油是人民群众的生活必需品,其消费量已成为衡量一个国家人民生活水平的重要标志,并在国家食物安全中占有重要的地位,保障其供给安全,对促进经济发展和社会稳定具有重要意义。文章收集整理了1978~2012年甘肃省油料作物和食用植物油相关数据,运用速度法和数理统计等方法,从产量、供给、需求、消费量、库存消费比等方面,分析研究甘肃省食用植物油供需波动变化情况。研究得出油料市场供给基本满足消费需求,但油料作物种植发展缓慢,产业化水平较低;食用植物油供需波动处于紧平衡状态,自给率仅为76%左右,省外购进的量远远大于外销量,消费需求的增长速度超过产量的增长,食用植物油缺口较大,同时存在种植品种与加工品种、品种结构与市场需求、区域性产销不协调之处。通过综合分析研究,构建了"以自给为主,贸易调剂为铺"的供给模式,提出了提高食用植物油安全供给的政策选择,为甘肃省食用植物油发展提供了新思路和科学依据,对保障甘肃省食用植物油安全供给具有重要意义。  相似文献   

17.
[目的]针对陕西省的节约型乡土园林植物资源展开调查,分析节约型乡土植物在园林规划和建设中的应用,以期为陕西省乡土植物应用于园林建设提供借鉴。[方法]文章采用实地调查法和专家咨询法,并结合查阅相关资料确定园区内的节约型乡土植物种类。根据园区记录的苗木种类和各自栽植数量采用统计分析法计算不同分类植物分别在8个园区同类植物中的使用占比。[结果]陕西省节约型乡土植物大约有53种,其中常绿乔木7种、落叶乔木15种、常绿灌木7种、落叶灌木16种、藤本植物3种、竹类2种、水生植物3种。常绿乔木主要涉及松科和柏科,落叶乔木包括漆树科、槭树科、杨柳科、木兰科、蝶形花科等,常绿灌木主要涉及黄杨科和小檗科,落叶灌木主要涉及蔷薇科和木樨科。经过对7个分组的节约型乡土植物在8个园林中分别占同类植物的种植比例的统计结果表明,节约型藤本植物和水生植物的占比远高于其他5个分组,常绿乔木、落叶乔木、常绿灌木、落叶灌木和竹类的占比分别介于43%~64%、52%~62%、41%~49%、50%~53%和50%~65%之间。[结论]陕西省节约型乡土植物种类包含30余科,这些植物普遍具有良好的环境适应性,且后期易于养护和管理。该类植物常作为本底植物在园林中使用,可在一定程度节省栽植和管理费用,达到节约型园林建设的目的。  相似文献   

18.
Extreme interannual variability of precipitation within Ethiopia is not uncommon, inducing droughts or floods and often creating serious repercussions on agricultural and nonagricultural commodities. A dynamic climate module is integrated into an economy‐wide model containing a detailed zonal level agricultural structure. This coupled climate‐economic model is used to evaluate the effects of climate variability on prospective irrigation and infrastructure investment strategies, and the ensuing country‐wide economy. The linkages between the dynamic climate module and the economic model are created by the introduction of a climate‐yield factor (CYF), defined at the crop level and varied across Ethiopian zones. Nine sets of variable climate (VC) data are processed by the coupled model, generating stochastic wet and dry shocks, producing an ensemble of potential economic prediction indicators. Analysis of gross domestic product and poverty rate reveal a significant overestimation of the country's future welfare under all investment strategies when climate variability is ignored. The coupled model ensemble is further utilized for risk assessment to guide Ethiopian policy and planning.  相似文献   

19.
Climate change is predicted to have major consequences for small-scale farmers in the developing rural areas of the world. Rural areas, nonetheless, harbor opportunities to mitigate global climate changes. Identification of innovative adaptation strategies used by small-scale farmers, therefore, is crucial in order to understand the extent of their implications. This paper identifies the relationships between livelihood units and landscapes that they depend upon, in a small-scale farm community. It examines their experiences of increasing climatic variability, and how the different groups in the community are adapting to it. The study was conducted in a typical rural ejido community on the Pacific coast of Mexico (Ejido Ticuiz), where a detailed socio-cultural profile was obtained by means of semi-structured interviews. In the study area we encountered a range of individual and community-based adaptation strategies, built on farmers’ recognition of the different types of landscapes which supply goods and benefits. Small-scale farmers have used their landscape diversity to build adaptation strategies to guarantee the supply of goods and benefits to cope with uncertain of climate events. Households rather than individuals or the community as an institution were depicted as the core socio-cultural group for better understanding of patterns, behavior and aspirations related to climate change adaptation at local level. The adaptation capacities of rural communities could be significantly strengthened if political, financial and institutional support is targeted at households rather than at individuals or the community level only.  相似文献   

20.
Reform of the Common Agricultural Policy and public concern over the environment have brought woodland into the public eye as an environment-friendly alternative land use in British agriculture. Survey evidence indicates that whilst it is the inadequacy of the returns from woodland that acts as the principal deterrent to planting, there are also a number of other factors that discourage woodland adoption. Of these, the perceived lack of flexibility that is associated with woodland figures highly. In part, loss of flexibility occurs due to the strength of controls such as felling licences and Tree Preservation Orders that restrict the conversion of woodland back to agricultural land. This paper develops a simple comparative static model of the way in which such restrictions impact on the allocation and price of woodland vis-à-vis agricultural land. Where felling controls are in operation they may reduce as well as preserve the area of woodland, and retard the efficacy of financial incentives. In this light, policymakers may do well to abolish felling restrictions on new woodland (possibly in conjunction with enhanced woodland incentives generally) if expansion of the wooded area is an explicit objective of future agricultural policy.  相似文献   

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