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431.
我国西南部喀斯特地区石漠化研究进展 总被引:38,自引:0,他引:38
我国西南部喀斯特地区的石漠化是西部生态建设中面临的十分突出的地域环境问题,也是西南喀斯特地区实现可持续发展的主要障碍之一。参考国内研究的相关文献,运用比较分析法,从喀斯特石漠化的概念、分布、评价指标、生态效应、成因分析及综合治理等六方面回顾了近年来我国喀斯特地区石漠化研究的进展情况。研究结果认为,目前研究中还存在基础理论研究落后于实践活动、定量分析不足、基础数据采集工作欠缺和现有治理模式具有较大的局限性等不足,并建议从研究重点区域、探究喀斯特石漠化演变机理、在喀斯特石漠化地区开展生态综合整治工作及建设相关的信息系统等方面开展先行研究工作。 相似文献
432.
我国生态安全现状分析及保护对策研究 总被引:3,自引:3,他引:3
生态安全是国家安全的重要组成部分,是国防安全、政治和经济安全的基础。笔者论述生态安全的基本含义、构成和特点,分析我国生态安全在国土资源安全、水资源安全、环境安全和生物物种安全等方面存在严重的问题,指出我国生态安全有加速恶化的趋势。以其为基础,提出了保护我国生态安全的具体对策和措施,为我国生态安全提供切实可行的手段和途径,旨在提醒国人对生态安全引起高度重视,有效保护我国的生态安全。 相似文献
433.
通过对雾灵山国家级自然保护区的调查,研究保护区的生态沿革,分析保护区的生态功能、生态作用等生态效应,针对当前所存在的草甸严重退化、动物种群密度降低、水量减少等生态问题,提出对保护区的生态环境应尽快制定环境保护规范化,建立生物多样性保护权威机构,实行社区共管,开展科学生态旅游等措施。 相似文献
434.
清代在水土资源、林木资源、矿产资源的保护与利用等方面采取了积极有效的措施,包括开垦土地、兴修水利、发展生态农业、植树造林、加强法制、设立环保机构等。 相似文献
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436.
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
437.
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
438.
Vegetation changes associated with barrier-dune construction on the outer banks of North Carolina 总被引:1,自引:0,他引:1
Manmade dunes are used to stabilize the barrier islands of the mid-Atlantic coast of the United States so that they are more amenable to development. Although this strategy has stabilized extensive sections of the barrier-island substrate, it has also caused significant ecological changes. The rate and pattern of the resulting vegetation changes along the Outer Banks of North Carolina were determined using sequential aerial photography. Successional trends have been altered in favor of more stable woody communities. 相似文献
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440.
福建三沙湾海洋生态环境研究 总被引:4,自引:0,他引:4
2000~2004年对三沙湾海洋生态环境进行了调查,分析了三沙湾海区多年来水质、水域养殖力(营养盐、叶绿素a和初级生产力)和浮游植物多样性的变化。调查后发现,养殖水域富营养化已经成为制约水产养殖业可持续发展的瓶颈,如何有效控制水体富营养化过程,降低海水养殖对环境产生的负面影响是一个非常现实的问题。因此,合理设置养殖容量、养殖方式、养殖种类,使退化的养殖海域得以修复,将对三沙湾海水养殖业的发展产生深远影响。 相似文献