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81.
James Fulton William L. Chase 《Journal of the American Water Resources Association》1979,15(2):426-435
ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed. 相似文献
82.
Robert G. Evans Wynn R. Walker Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1980,16(1):133-135
ABSTRACT: Recently, Congress designated irrigated agriculture under the “nonpoint source” category, covered by Section 208 of P.L. 92-500 and involves the use of “best management practices.” Generally, the most appropriate solutions for pollution abatement from irrigated agriculture involve the delivery and use of water rather than the treatment of irrigation return flows. 1. Technological alternatives should be utilized that are sensitive to local conditions and acceptable to the farmers. 2. Informational and educational programs to assist farm operators individually and collectively must be instituted prior to the start of the project; imaginatively conceived, and continuously modified and upgraded if motivation for change is to be encouraged. 3. Technical assistance personnel should be given short courses in skills needed for working effectively with irrigators. 4. Communication techniques used for working with farmers as individuals and groups should be designed into the implementation program and evaluated. 5. Credibility and trustworthiness of Federal and state agencies in the eyes of the irrigators provide the important final ingredient in effectively implementing change and reducing nonpoint source pollution from irrigated agriculture. 相似文献
83.
Hauke Von Seht 《Local Environment》2013,18(1):23-34
Local environmental policies are sometimes seen as standing in the way of socio-economic progress. Against the background of these concerns, the actual socio-economic impacts of climate protection measures are discussed in this paper. It is structured as follows. First, the concept of primary and secondary effects of climate policies is introduced. Secondly, there is a discussion of financial and economic impacts of local climate policies. Finally, information is given on the consequences of such measures for local energy security and air quality. The main conclusion is that, at least in the field of climate policies, there is a huge potential for local measures that are socioeconomically attractive to local communities. HAUKE VON SEHT, Impactos socio-económicos de políticas del medio ambiente local, un análisis para el campo de protección climática . Las políticas ambientales locales son vistas algunas veces como si estuvieran en la via del progreso socio-económico. En contra de los antecedentes de estos asuntos, los impactos socio-económicos actuales de las medidas de protección climaticas son discutidos en este documento. Está extructurado de la siguiente manera: Primero serán introducidos el concepto de efectos primarios y secundarios de las políticas climáticas. Luego sigue una discusión de impactos económicos y financieros de las políticas climáticas locales, seguido por información de las consecuencias de tales medidas para la calidad del aire y seguridad de energía local. La conclusión principal es que por lo menos en el campo de las políticas climáticas hay un inmenso potencial de medidas locales que son socio-económicamente actractivas a las comunidades locales. 相似文献
84.
生态环境保护与农业可持续发展研究 总被引:1,自引:0,他引:1
针对生态环境保护与农业可持续发展问题,探讨了生态环境对农业可持续发展的影响,包括陕西省农业资源的现状、陕西省农业生态环境恶化、生态系统功能遭到破坏和由于生态环境恶化使自然灾害发生,探讨了保护生态环境与促进农业可持续发展,内容包括要积极保护生态环境促进农业可持续发展、要积极保护农业资源促进农业可持续发展、要积极发展现代农业科技促进农业可持续发展和要积极宣传生态环境保护促进农业可持续发展. 相似文献
85.
86.
随着资源的紧张和环境的恶化,发展现代循环农业对提高资源利用率和环境保护具有至关重要的意义。因此本文从低碳经济理论的内涵与发展、现代循环农业与主要技术对策、绿色农业视野三个层面的资源循环利用来综合分析如何发展现代农业。 相似文献
87.
用清洁生产的理念防治农业污染的初步探讨 总被引:6,自引:0,他引:6
农业发展面临的农业污染问题,已成为制约农业可持续发展的"瓶颈".农业污染问题已经成为影响农村经济发展,以及农村社会和谐发展的重要因素之一.在论述农业清洁生产涵义的基础上,探讨了农业清洁生产防治农业污染问题.以新疆绿洲农业为例,论述了农业污染现状及发展农业清洁生产的必要性,分析探讨了发展农业清洁生产存在的问题和障碍,并提出了对策和建议. 相似文献
88.
陶战 《中国人口.资源与环境》1994,4(1):62-64
中国农业经历了多种策略阶段,可持续发展策略是新近出现的最先进、最适合现在和将来农业发展的策略。新策略带有系统性原理,其实质是发展与生态环境保护协调的农业。因此,可持续发展措施应同时重视解决农业经济发展与生态环境保护两方面的问题。据此,本文提出了六项措施。 相似文献
89.
为了科学合理施用磷肥,减小对设施农业环境带来的污染风险,以北京市大兴区设施农业集中区为研究对象,通过对不同种植年限设施农业剖面土壤(0~100 cm)磷素含量的测定分析,探究磷素累积与迁移转化特征.结果表明,设施农业表层土壤全磷和有效磷含量变化范围大,显著高于周边粮田土壤,主要跟不同种植年限农户的施磷量相关,随着土层深度的增加,全磷和有效磷含量逐渐减小,呈现表聚特征,其中土壤ω(全磷)范围在0.38~2.58 g·kg-1,ω(有效磷)范围在1.60~256.00 mg·kg-1.随着种植年限的增加,土壤全磷和有效磷含量呈现先增加后减小的趋势,在15 a左右达到峰值,随后逐渐减少,趋于稳定,总体处于较高水平.无机磷主要集中在设施农业表层土壤,其中Ca-P占无机磷的比例最大,达到了98.38%,Ca10-P是最主要的Ca-P形态,含量占Ca-P的78.70%,Ca2-P占比最小,仅占9.50%.不同形态无机磷含量呈现表层土壤富集,向下减少的垂直分布特征;不同土层深度,不同形态无机磷占全磷比例变化存在差... 相似文献
90.
Travis Warziniack 《Journal of the American Water Resources Association》2014,50(3):683-695
This study builds a general equilibrium model of ecosystem services, with sectors of the economy competing for use of the environment. The model recognizes that production processes in the real world require a combination of natural and human inputs, and understanding the value of these inputs and their competing uses is necessary when considering policies of resource conservation. We demonstrate the model with a numerical example of the Mississippi‐Atchafalaya river basin, in which grain production in the upper basin causes hypoxia that causes damages to the downstream fishing industry. We show that the size of damages is dependent on both environmental and economic shocks. While the potential damages to fishing are large, most of the damage occurs from economic forces rather than a more intensive use of nitrogen fertilizers. We show that these damages are exacerbated by increases in rainfall, which will likely get worse with climate change. We discuss welfare effects from a tax on nitrogen fertilizers and investments in riparian buffers. A 3% nitrogen tax would reduce the size of the hypoxic zone by 11% at a cost of 2% of Iowa's corn output. In comparison, riparian buffers are likely to be less costly and more popular politically. 相似文献