Revisiting the Impact of Order Effects on Sensitivity to Scope: A Contingent Valuation of a Common‐Pool Resource

While many studies have employed stated preferences methods to estimate the value of non‐market ecosystem goods and services, contingent valuation (CV) still generates a significant amount of criticism. Besides ethical concerns, two of the key criticisms relate to insensitivity to scope and order effects. We examine the expectation that the presence of order effects in stepwise disclosure procedures affects the degree of scope sensitivity. We use data from a CV exercise asking farmers in Southern Spain to value two different levels of guarantee of water supply for irrigation in a context of water scarcity. We find that despite order effects being present, they do not affect the existence or the degree of sensitivity to scope. We conclude that, in the light of the mixed evidence found in the literature and the results of our study, it does not seem justified to ascribe order effects and their connection with sensitivity to scope to study design alone (e.g. step‐wise versus advanced disclosure, top‐down versus bottom‐up). The nature of the environmental good under valuation also matters. Our study of irrigation water as a common‐pool resource suggests that, when clear private benefits also exist, these appear to override any ‘good cause dumping effect’ that might arise from the public good component.     

浅析小型水利灌溉供水设施的产业化经营

利用产业组织经济学中贝恩的“结构一行为一绩效”经典分析框架，对农村集体经营和产业化经营两种组织结构的定价行为及其产生的经济效果进行了比较分析，从而证明小型灌溉供水设施产业化运作的可行性并且具备更优的经济效率，并就如何更好的实现小型水利灌溉供水设施的产业化经营提出了建议。     

Irrigation Technology Adoption and Gains from Water Trading under Asymmetric Information

We develop a water allocation and irrigation technology adoption model under the prior appropriation doctrine with asymmetric information among heterogeneous farmers and between farmers and water authorities. We find that adverse selection reduces the adoption of modern irrigation technology. We also show that even with asymmetric information, incentives for water trade exist and lead to additional technology adoption with gains to all parties. This suggests that under asymmetric information, a thin secondary market improves the allocation of water resources and induces additional adoption of modern irrigation technologies.     

松嫩平原稻区防止次生盐渍化的研究

松嫩平原种稻区防止土壤次生盐渍化技术研究表明，合理灌溉，加强排水，增施有机肥，调控水盐平衡和肥盐平衡，是农业生产中的一个重要问题。通过旱改水稻稻治涝防止土壤次生盐渍化技术的研究，明确了井灌，渠灌，井渠结合灌溉对土壤次生盐渍化的影响。     

对农业水利工程建设和管理问题的探讨

农业是关系到我国人民生活水平高低的基础性行业,农业生产被给予更多重视。而农业水利基本设施建设是直接影响着我国的农业生产的关键性因素。是农民在生产生活中不可忽略的问题。笔者在文章中就农业水利工程中最常见的一些问题进行探讨,为农业水利工程建设提供相应的参考意见和建议。     

基于无线传感器网络的节约型农业灌溉自动化技术研究

文章分析了当前国内外农业灌溉技术的现状并提出了解决措施。文中提了基于无线传感器网络的节约型农业灌溉自动化技术,利用有线或无线网络,在该系统研究的土壤中人为安放水分传感器、温度传感器,对农作物的生长条件进行监控,根据实际,进行自动供水和自动按一定顺序进行灌溉。其目的就是感知、采集和处理网络覆盖的地理区域中感知对象的信息,并发布给观察者,而观察者根据实际做出适应性调整。     

实行农田灌溉“以电代油”,促进节能减排

加强农村电网建设,提高农灌电力设施供电能力,可降低灌溉成本,减轻农民负担。而且通过＂以电代油＂,能有效节约能源,减少有害物质的排放,缓解石油紧张,对我国实现节能减排目标,建设节约型社会具有重要意义。     

Upstream demand for water use by new tree plantations imposes externalities on downstream irrigated agriculture and wetlands*

Large‐scale tree plantations in high rainfall upstream areas can reduce fresh water inflows to river systems, thereby imposing external costs on downstream irrigation, stock and domestic water users and wetland interests. We take the novel approach of expressing all benefits and costs of establishing plantations in terms of $ per gigalitre (GL) of water removed annually from river flows, setting upstream demands on the same basis as downstream demands. For the Macquarie Valley, a New South Wales sub‐catchment of Australia’s Murray‐Darling Basin, we project changes in land and water use and changes in economic surpluses under two policy settings: without and with a policy requiring permanent water entitlements to be purchased from downstream parties, before plantation establishment. Without the policy, and given a high stumpage value for trees ($70/m³), upstream gains in economic surplus projected from expanding plantations are $639 million; balanced against $233 million in economic losses by downstream irrigators and stock and domestic water users for a net gain of $406 million, but 345 GL lower mean annual environmental flows. With the policy, smaller gains in upstream economic surplus from trees ($192 million), added to net downstream gains ($138 million) from sale of water, result in gains of $330 million with no reduction in environmental flows. Sustaining the 345 GL flow for a $76 million (406–330) reduction in gains to economic surplus may be seen to cost only $0.22 million/GL; but this is much lower than the market value of the first units of that water to agriculture and forestry.     

淠史杭灌区水利建设与管理的思考

水利是现代农业建设不可或缺的首要条件,是经济社会发展不可替代的基础支撑。农田水利基础设施是提高农业生产力的物质基础。淠史杭灌区六十年来,在基础设施建设与综合管理中取得了长足的发展和进步。文章通过调查,分析了淠史杭灌区水利建设60年来的成功经验,剖析了其建设和管理中所存在的问题,并从建设过程和建成后管理两个角度提出了一系列相关的对策。     

我国农户参与灌溉管理的产权制度保障

灌区农民用水者协会的管理模式能够提升农民管理灌溉系统的集体行动空间,从而有效解决灌区水资源利用所出现的恶性循环,但由于权利转移的不充分,当前我国灌区农民用水者协会的进一步发展面临着众多的制约。