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1.
以家庭均包制为主要经营特征的农村土地制度曾一度引致农户农业生产积极性的提高和农业生产效率的快速增长,但由此导致的细碎化小规模的农地经营特征和农业生产成本的上升却造成了农地经营的自我剥削现象普遍存在,加之传统的村庄惯习和土地占有关系诱致的农户对农地的禀赋效应,共同导致农户农地经营的自我剥削属性与土地的市场处置行为呈现出内在运行机制不一致性。为此,本文采用引入交叉项的Probit模型,并利用江西省丰城市和遂川县的706户农户调查数据经验分析了小农户的自我剥削和农地禀赋效应对农地流转潜在市场发育的影响。理论分析表明,农地经营的自我剥削特征与农地市场化具有一致性倾向,但农地的人格化财产属性引致的农户禀赋效应造成了农户农地经营自我剥削感知度的下降,并削弱了要素经营属性与市场配置行为的匹配。经验分析结果发现,小农户低效率农地经营导致的自我剥削与农地禀赋效应分别激励农地流转市场的潜在供给和需求。同时,农地禀赋效应弱化了自我剥削对农地流转潜在需求和供给的诱发作用。为此,本文认为降低农户的土地禀赋效应是欠发达地区小农户转型的总体方向,它为农地由小农户流向生产大户和培育部分小农户成为新型农业经营主体提供保障。文章主要从家庭决策的利益导向化、农地流转市场与劳动力市场发展的不一致性及农村制度供给等维度提出了经济欠发达地区小农户转变农业生产方式,跳出自我剥削陷阱的政策建议。具体措施包括:1切实保障小农户的基本权益,提高他们在家庭资源配置中的预期收益;2在初次规模经营补贴、农业基本补贴机制转变、经营者生产奖励、专业技能培训、市场信息供给等层面加大投入力度,同时完善农村社会保障体系,以降低小农户转型的难度与风险。  相似文献   

2.
The RTMOD system is presented as a tool for the intercomparison of long-range dispersion models as well as a system for support of decision making. RTMOD is an internet-based procedure that collects the results of more than 20 models used around the world to predict the transport and deposition of radioactive releases in the atmosphere. It allows the real-time acquisition of model results and their intercomparison. Taking advantage of the availability of several model results, the system can also be used as a tool to support decision making in case of emergency. The new concept of ensemble dispersion modelling is introduced which is the basis for the decision-making application of RTMOD. New statistical parameters are presented that allow gathering the results of several models to produce a single dispersion forecast. The devised parameters are presented and tested on the results of RTMOD exercises.  相似文献   

3.
华北平原冬小麦-夏玉米种植模式碳足迹研究   总被引:17,自引:0,他引:17  
农业碳足迹理论可以系统评价农业生产过程中人为因素引起的碳排放,是构建低碳农业的理论基础,对实现低碳农业其有重要的指导意义.为探明农业生产中的碳足迹,本文基于河北吴桥县农户生产调查数据,利用农业碳足迹理论及研究方法,评价了华北平原冬小麦-夏玉米两熟种植模式的碳足迹.结果表明:冬小麦-夏玉米种植模式碳足迹的大小为1 737.37±337.02 kgCe/hm2·a,生产1 kg粮食的碳成本是0.12±0.03 kgCe,其中冬小麦的碳足迹是1 101.31±251.91 kgCe/hm2·a,小麦的碳成本是0.16±0.04kgCe/kg,夏玉米的碳足迹是636.06±163.90 kgCe/hm2·a,玉米的碳成本是0.08±0.02 kgCe/kg.冬小麦-夏玉米种植模式碳足迹的组成中,化肥占总量的61.76%,电能占25.03%,柴油占7.44%,种子占4.75%,农药占1.02%.同时,发现N肥的施用量和电能消耗量均与碳足迹有正相关性,种植规模与碳成本有负相关性.因此,构建节肥、节水及规模化的低碳种植模式是实现华北平原农业节能减排的重要途径.  相似文献   

4.
近年来粮食安全受到国家和社会的广泛关注,农地投入作为粮食生产的重要要素,是保障粮食稳定产出的前提。学者就农地规模对农户种粮投入的影响已进行了较多研究,但受农地流转的影响,土地要素更具多样化,土地规模与农户种粮投入的关系发生变化。随着农地流转在我国的快速发展,探析农地流转影响下土地规模对农户种粮投入影响的变化成为一个亟待研究的问题,对保障国家粮食安全具有重要意义。考虑到地块的异质性,本文基于山东、河南、安徽三个粮食主产省622户农户1 284个地块的粮食生产数据从村庄和农户两个层次控制了生产要素市场价格、地块要素等非主观因素,进行多层模型回归分析。结果表明,农地流转特征及地块特征对农户粮食生产单位面积投入有显著影响。地块规模和转入地占比对农地投入影响为负,转入地占比越大,地权稳定性越低,农户投入积极性受到挫伤越明显,在转入地上的投入减少。随着转入土地面积的增加,农户从事粮食生产的机会成本增大,使其有更强的动力增加种粮投入,地块规模的负向影响程度降低。基于分析结果,本文得出以下3点结论:(1)规模化经营有利于降低单位面积种粮成本;(2)农地流转发生时,地块规模对种粮投入的影响发生改变,成片规模化经营将成为我国粮食生产的必然趋势;(3)提高土地综合条件可以降低投入成本,并提高农户投入积极性。要保障国家粮食安全,需从降低种粮成本、提高农户收益着手,建议鼓励农村土地流转,推动粮食规模化生产,同时也要注重增加财政拨款,建设高标准粮田,强化高标准粮田的农业基础设施建设,完善田间配套工程。  相似文献   

5.
The STRATEGY project (Sustainable Restoration and Long-Term Management of Contaminated Rural, Urban and Industrial Ecosystems) aimed to provide a holistic decision framework for the selection of optimal restoration strategies for the long-term sustainable management of contaminated areas in Western Europe. A critical evaluation was carried out of countermeasures and waste disposal options, from which compendia of state-of-the-art restoration methods were compiled. A decision support system capable of optimising spatially varying restoration strategies, that considered the level of averted dose, costs (including those of waste disposal) and environmental side effects was developed. Appropriate methods of estimating indirect costs associated with side effects and of communicating with stakeholders were identified. The importance of stakeholder consultation at a local level and of ensuring that any response is site and scenario specific were emphasised. A value matrix approach was suggested as a method of addressing social and ethical issues within the decision-making process, and was designed to be compatible with both the countermeasure compendia and the decision support system. The applicability and usefulness of STRATEGY outputs for food production systems in the medium to long term is assessed.  相似文献   

6.
In this paper I undertake a preliminary assessment for the tropics of the relation of economic development, meaning in general increases in economic activity as measured by e.g. GDP, and its normal biophysical corollaries of increased resource use and land use change. I also examine each in relation to the intellectual concepts that underlie and guide what is commonly called economic development. Because most of the development literature is derived from economics or other social sciences, and focuses almost entirely on lifting people’s standards of living as measured in monetary units, very little examines the per unit biophysical requirements of that development, including energy or other resource use requirements, land use change or other environmental consequences of development plans. In addition there seems to be insufficient connection between those who create economic development plans and those who undertake empirical biophysical assessments to determine whether the development plan has worked or can possibly work. The problem is deeper: there exists a series of models used in the development literature that have been used to encourage and guide development. These models have received very little scrutiny as to either their efficacy or their societal or environmental impacts until quite recently. When this has been done the models have been shown to fail miserably. It is time to develop a new model of development that synthesizes conventional economic, biophysical economic and social aspects, and that is based on the scientific method rather than on perceived wisdom. This model must also take into account population growth, issues of who wins and who looses from economic development, and the implications of the incipient peak in global oil production.  相似文献   

7.
基于整体开发管理的国际河流决策支持系统   总被引:1,自引:0,他引:1  
基于国际河流开发管理的现状,分析国际河流整体开发管理理论的演进。得出整体开发管理决策实施的原则及思路:流域开发管理要以流域边界为界,将整个水系自然联系的区域作为不可分割的整体,进行统一权衡,突出共同利益,流域内开发与流域外开发相结合。以建立多层次的国际合作机构。对国际河流决策支持系统进行设计,即以国际河流流域为体系,各国国内流域测点为单元。国际流域综合协调委员会为决策支持中心、各国流域机构委员会为决策支持分中心。并研究系统的公用信息平台建设,信息开发、管理与维护。河流水资源、水环境实时监控等技术支持系统。实证分析澜沧江-湄公河流域决策支持系统的建设。并指出国际河流水资源的开发与管理,水权等问题有待进一步深入研究。  相似文献   

8.
Can information about adaptation costs influence citizens’ willingness to support climate change mitigation? Some scholars are concerned that policy discussions on adaptation might present climate change as a more manageable problem, and therefore crowd out mitigation efforts. On the other hand, providing information on adaptation costs may sensitize citizens to these costs, thereby increasing their willingness to support mitigation. To assess these conflicting predictions, we fielded a web-based survey experiment using a sample of 2,000 US-based respondents. We presented the respondents with a hypothetical newspaper article regarding a proposed gasoline tax (a mitigation strategy) and measured the support for this proposal across different treatment groups. In the control group, the respondents were told that failure to mitigate climate change could result in a potentially catastrophic outcome, whereas in each of the treatment groups the respondents were provided with information concerning possible adaptation costs. The respondents were then asked about their willingness to support a gasoline tax. Our key finding is that the provision of information about adaptation costs leads to a small increase in the respondents’ willingness to support mitigation efforts. Furthermore, we find that this effect becomes larger when the information regarding adaptation costs is made more specific.  相似文献   

9.
Most retail and on-line outlets allow customers to easily return defective or even non-defective products. Due to increasing environmental and sustainable concerns, disposal of returned products is often costly and undesirable. Furthermore, these products contain parts and materials of value that can contribute to the companies' profit. One way to take advantage of these returns is by utilising good returned parts in production of after-market products. Recycling of parts from products at the end of their useful lives has been studied for a long time. Many of these studies, however, are focused on repairs and refurbishing of such products for reuse.

This paper addresses recycling of rather new parts recovered from returned products. In this process parts are assembled with other parts recovered from other products to make a complete unit. The main objective of this study is to provide quantitative decision rules for justification of recycling of returned parts. The proposed method consists of a computer-based simulation decision model that, given a set of production system parameters, determines the breakeven point for the primary production rate at which recycling is justified. The application of the system to several scenarios is demonstrated through a numerical example.  相似文献   

10.
Apple farmers in Kazuno, northern Japan, have started to grow peaches in the northernmost climatic region suitable for peach farming. Here, we investigate the process from the initial introduction of peach cultivation to its diffusion focusing on the farmers’ perceptions of climatic and non-climatic stimuli and their actions to respond to these stressors. Interviews with the farmers identified three distinct groups. Four farmers (Group 1) initiated the transition to peach production, which then spread to other farmers (Group 2) via personal connections. Later, after the provision of various means of support from the local government and the producers’ cooperative, many more apple farmers (Group 3) decided to begin peach production. Most farmers recognized the risk of damages to apple production as a result of typhoons and drought. However, only Group 1 farmers, who depend on direct sales to customers, mentioned these climate-related damages as a reason to shift toward peach cultivation in order to maintain their customers. The peach fruit was specifically chosen as a replacement for apple because it is less vulnerable to these climatic stressors. For Group 3 farmers, the financial losses associated with these climate-related events could be compensated for by insurance. Their decision to grow peach is largely due to its higher price and immunity against a specific disease which affects apples but they only shifted once institutional support was available, thereby reducing the risk in cultivating a new species. Our findings suggest that the role of institutions was not to drive the process of the adaptation itself but rather to provide relevant support to farmers to enable them to shift to new crop varieties more easily. We argue that such process-based understanding is crucial in formulating strategies to increase adaptive capacity in agriculture.  相似文献   

11.
Land degradation and desertification have become severe environmental problems in arid areas due to excessive use of water resources. It is urgent to reduce agricultural water use for ecological rehabilitation, which may result in a decrease in agricultural production and farmer's welfare. This paper focused on the impacts of some main measures including extensions of watersaving irrigation, expanding solar green house and increasing off-farm employment, which are generally recognized to be important to alleviate water shortage and poverty. A bioconomic model is applied taking Minqin Oasis in Gansu Province as a case study site. Simulation results showed that the effect of expanding solar greenhouse was more positive than other ones so it drew more attention. On the view of the different effects between each irrigation zone, mixed policy patterns suitable for them are suggested. In Baqu, expanding solar greenhouse should be the most important, auxiliary with encouraging pipe irrigation. Inversely, with regard to Quanshan, the major attention should be paid to subsidy for pipe irrigation and it would be better to supply the off-farm employment opportunities to the households in Huqu, where the expanding of solar greenhouse should also be summoned. Finally, it should be noted that farmer's income would only resume to 90% of the current level in the short run by putting more effort into local policies. Thus, the ecological compensation is needed to ensure farmer's welfare.  相似文献   

12.
This paper presents a generic framework integrating environmental and social criteria leading to a comprehensive selection process of green suppliers. Traditionally, price, quality, lead time and flexibility are considered for the supplier selection. With the increase in awareness of environmental and social responsibility issues, many companies are tending towards adopting green concepts and sourcing green suppliers. This study proposes a framework consisting of environmental (E), green (G) and organisational (O) factors that are required for the green supplier selection process. These factors are further classified as criteria for which attributes are presented. A hierarchy is constructed to facilitate in evaluating the importance of the selected criteria and alternatives of green suppliers. To cater to the multi-criteria decision-making approach with both quantitative and qualitative attributes, we applied the multiple attribute utility theory, which is a decision support that helps managers formulating viable sourcing strategies. A hypothetical example is presented to illustrate the applicability of the approach.  相似文献   

13.
The contribution contained in this paper focuses on providing a possible framework or approach in respect of how manufacturing companies can economically introduce environmentally friendly practices to their production operations, whilst at the same time encouraging organisational and operational learning with the aim of eventual evolution of the firm into an eco-efficient concern. A key premise associated with the approach advocated is economical organisational and operational learning over time, thus providing a sequential movement of the company through various stages of cultural change and technological capability to eventually achieve eco-efficiency in its production activities. At each stage in the process, it is suggested that a balance must be maintained between on the one hand, a reduction in operational economics consistent with on the other hand, an improvement in the environmental sustainability of company activities. To that end, some previously suggested monitoring metrics are examined in the text for their efficacy and economic rapport via hypothetical examples of how they might be applied in practice to monitor movement towards industrial–environmental sustainability.  相似文献   

14.
Environmental disputes arise due to opposing views of various groups about their environmental concerns and their economic or developmental interests. Development and protection of the environment constitute two main contradictory objectives within the sustainable development paradigm, which are often in conflict. The decision support system, GMCR II, which implements the graph model for conflict resolution, is employed to model and analyze an environmental dispute arising over the construction of a new freeway between the Iranian capital, Tehran, and the city of Chalous located in the north of the country. This study demonstrates that the graph model for conflict resolution can be used as a methodology to promote a reasonable balance between economic development and environmental protection from a strategic viewpoint. In addition to systematically modelling the conflict by putting the existing information into proper perspective, it is shown how conflict analysis can be used for comparing alternative scenarios and predicting possible future outcomes. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

15.
Over the last three decades, new concepts, strategies, frameworks and systems have been developed to tackle the sustainable development issue. This paper reviews the challenges, perspectives and recent advances in support of sustainable production operations decision-making. The aim of this review is to provide a holistic understanding of advanced scientific analysis methodologies for the evaluation of sustainability, to provide efficient decision support. Over 100 publications have been analysed, and a characterisation of state-of-the-art sustainability analysis methodologies has been produced, which includes life cycle assessment and multi-criteria decision analysis (MCDA), along with their applications to three key areas of production operations: sustainable design, sustainable manufacture and sustainable supply chain management. Distribution of existing work is discussed and future research directions are elicited from the literature. The paper finds three trends in supporting sustainable production operations decisions: (a) sustainability analysis has moved to whole life cycle assessment from single-stage assessment, (b) sustainability analysis has shifted away from single criterion to MCDA and (c) sustainability analysis has evolved from stand-alone approaches to integrated systematic methodologies. The paper concludes that integrated sustainability analysis can provide more efficient and effective support to complex decision-making in sustainable production operations.  相似文献   

16.
基于农户兼业视角,利用湖北省农村地区的微观调查数据,运用Logistic回归模型比较了不同兼业类型农户农业废弃物资源循环利用意愿及其影响因素。研究结果显示:(1)大部分农户具有农业废弃物资源循环利用意愿,其中纯农户和一兼农户的利用意愿相当,且高出二兼农户;(2)农户对农业废弃物资源价值的感知是影响不同兼业类型农户利用意愿的共同因素,农户感知农业废弃物资源的价值越高,其利用意愿也越强;(3)影响不同兼业类型农户利用意愿的因素有明显差异,性别对农户尤其是二兼农户的利用意愿有显著的正向作用;年龄对纯农户和二兼农户利用意愿的影响均为负,尤其是对纯农户影响更大;土地经营规模对农户尤其是一兼农户的利用意愿有显著的正向影响;对获取经济收益的感知正向作用于一兼农户和二兼农户的利用意愿,尤其是对一兼农户有更大程度影响;对纯农户而言,对自身经济条件的感知也显著影响其利用意愿  相似文献   

17.
虚拟水战略:拯救民勤绿洲的新思路   总被引:11,自引:0,他引:11  
位于甘肃石羊河下游的民绿洲,水资源极度缺乏,生产、生活和生态用水矛盾突出,出现了严重的生态危机,其中湖区的生态经济系统已呈“崩溃”之势。拯救民勤绿洲成为社会广泛关注的重大问题。“虚拟水”是20世纪90年代初Tony Allan提出的一个新概念,虚拟水战略是指贫水区域通过贸易的方式从富水地区购进水资源密集型产品来获得本区水资源安全的一种构想。本文通过对节水、调水、移民等常规方案与虚拟水战略的对比分析后,认为虚拟水战略是拯救民勤绿洲的一个全新思路,探讨了虚拟水战略实施的政策建议;提出了创新区域水资源管理体制和区域经济发展思路以及建立国家生态补偿机制的主张。  相似文献   

18.
大麦是世界四大谷类作物之一,以适应性强、抗塑性强、抗逆性好、用途广而在世界各大洲广为种植。二次世界大战后,随着经济发展,大麦产量由60年代的9970.0万t增加到1994年的15872.8万T,长江 中游历来是我国大麦的主要种植之一,随着我国经济的发展,大麦生产经况愈下,成为我国进口量最大的农产品之一,其种植面积由1961年77.927万hm^2降为1995年的8.348万hm^2,与世界经济越发  相似文献   

19.
A spatially implemented model designed to assist the identification of optimal countermeasure strategies for radioactively contaminated regions is described. Collective and individual ingestion doses for people within the affected area are estimated together with collective exported ingestion dose. A range of countermeasures are incorporated within the model, and environmental restrictions have been included as appropriate. The model evaluates the effectiveness of a given combination of countermeasures through a cost function which balances the benefit obtained through the reduction in dose with the cost of implementation. The optimal countermeasure strategy is the combination of individual countermeasures (and when and where they are implemented) which gives the lowest value of the cost function. The model outputs should not be considered as definitive solutions, rather as interactive inputs to the decision making process. As a demonstration the model has been applied to a hypothetical scenario in Cumbria (UK). This scenario considered a published nuclear power plant accident scenario with a total deposition of 1.7x10(14), 1.2x10(13), 2.8x10(10) and 5.3x10(9)Bq for Cs-137, Sr-90, Pu-239/240 and Am-241, respectively. The model predicts that if no remediation measures were implemented the resulting collective dose would be approximately 36 000 person-Sv (predominantly from 137Cs) over a 10-year period post-deposition. The optimal countermeasure strategy is predicted to avert approximately 33 000 person-Sv at a cost of approximately 160 million pounds. The optimal strategy comprises a mixture of ploughing, AFCF (ammonium-ferric hexacyano-ferrate) administration, potassium fertiliser application, clean feeding of livestock and food restrictions. The model recommends specific areas within the contaminated area and time periods where these measures should be implemented.  相似文献   

20.
Access to extractive resources relies as much on technology and prices as it does on the power to designate ecological and economic meanings to water and other environmental goods. This paper examines the ways in which the mining industry uses scientific models to create meanings for water that in turn legitimizes their access to and control over it. To do so, this paper explores the relevance of combining biophysical analyses—in this case water metabolism—with an examination of those power relations and social constructions that coexist with and affect the flows of water. Based on empirical research, this paper analyzes the evolution of water management in the process of copper production at the Cobre las Cruces mine in southern Spain to identify present contradictions in the strategies adopted by the mining company to avoid water degradation. These contradictions are revealed by examining how water has been framed as a resource not susceptible to being used for purposes other than mining processes. We argue that those framing this environmental explanation—the regional government and the mining industry—are promoting net subtractions of water from an aquifer against current regulations.  相似文献   

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