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451.
452.
In this paper we quantify the additional water quality benefits that can be achieved through coordinated cumulative impact management. To do this we simulate coordinated and un-coordinated revegetation investments and compare their impact on achieving regional water quality goals. Our results show that coordination between multiple mining companies achieves additional benefits since prioritization is enabled across a broader range of investment opportunities. Additionally, when coordinated investment is permitted beyond the boundaries of coal mining leases, results show that additional benefits are greatly enhanced since these regions provide more rewarding investment opportunities. Results illustrate (a) how regional coordination may influence reputational benefits of investments, and (b) that coordination is beneficial when investment opportunities are unevenly distributed across the landscape. When additional benefits are achievable, we suggest that mining companies should develop collective investment projects with an understanding of how coordination influences project costs. Similarly, investment projects should be developed with an understanding of investment tradeoffs and how these may adversely impact on regional stakeholders and hence industry reputation. The mining industry has significant potential to contribute to regional wellbeing; however, land management policies must be flexible and promote incentives to enable companies to invest beyond compliance. 相似文献
453.
全面分析了青藏高原东部藏族地区(简称藏东地区)农业资源特点及开发利用现状,阐明了农业资源开发利用中出现的生态环境问题及成因,提出了该地区农业资源合理开发,持续利用和生态环境保护的对策和措施。 相似文献
454.
淮河流域可持续发展研究的重点问题 总被引:1,自引:0,他引:1
以可持续发展的基本理论为指导 ,本研究选定淮河流域为研究的典型区域 ,试图通过对淮河流域社会、经济、资源、环境的系统分析 ,提出实现大河流域可持续发展战略的基本思路与框架 相似文献
455.
Neil Glasson 《Journal of Environmental Planning and Management》1987,30(2):84-90
This paper looks at the use and effectiveness of the Site of Special Scientific Interest designation in three counties in the East Midlands region of the Nature Conservancy Council, namely Nottinghamshire, Northamptonshire and Cambridgeshire. Using unpublished sources within the NCC an analysis is made of the SSSI system in practice since its inception in 1949. A number of findings relating to weaknesses in the designation and the operation of the designation system emerge. Each of these findings is discussed in turn with the presentation of the appropriate evidence from the county case studies. 相似文献
456.
Peter C. Rosendahl Thomas D. Waite 《Journal of the American Water Resources Association》1978,14(5):1227-1238
ABSTRACT: Comparisons were made between rates of movement of orthophosphate in a canal and a meandering stream. The meander system had greater algal and macrophyte phosphate uptake rates, and lower plankton and sediment release rates compared to the canal. Chemical precipitation and direct rainfall influences on orthophosphate movement were insignificant relative to other terms. The major source of phosphorus to both systems was from upland runoff. The impact of this source was greater on the meandering system due to the smaller channel volume. When secondary effects of meandering were considered such as marsh inundation, the net orthophosphate movement within the meandering channel was less than that for the canal; due to the lower concentrations of phosphorus in marsh effluent waters. Field experiments were conducted to compare the longitudinal dispersion coefficient between a canal and meandering river system; the meandering stream had a dispersion coefficient over 17 times that measured for the canal. Rates of orthophosphate movement were combined into a single mass transport equation, and a numerical solution was obtained. Internal river and canal channel processes were overshadowed by external point source loadings. 相似文献
457.
加强长江流域东西部经济协作与协调发展的思考 总被引:3,自引:1,他引:2
长江流域东西部经济协作和协调发展是长江流域经济整体协调发展和西部大开发战略的重要组成部分。首先分析了长江流域东西部经济协作在政策、自然资源、产业第补性、区位等方面的潜力及突出优势、进而论述了流域东西部经济协作的现状及其存在的流域东西部地区间流通通道不畅、经济整体性差,内部联系松散、管理人才缺乏等问题,在此基础上针对性地提出现阶段流域东西协作应把合作加强基础设施建设、联合开发资源,加强生态环境保护、联手开拓市场,并对国有大中型企业进行兼并和重组、建立人才资源培训交流机制等作为协作的重要领域。同时,提出了经济协作过程中应注意的诸如协调机制的建立、流域经济协作主体的确定、政策制定及其引导、流域经济协作目标等问题。 相似文献
458.
乌江流域梯级开发的不良环境效应 总被引:14,自引:6,他引:8
苏维词 《长江流域资源与环境》2002,11(4):388-392
乌江流域梯级开发是我国一项较大的流域开发系统工程,20世纪60年代国家规划在乌江干流建立11个梯级电站,装机容量达834万kW。目前普定,东风和乌江渡水电站已建成,其余的正在建设或筹建中。乌江流域梯级开发在促进该流域经济发展的同时,也将带来水良环境效应。结合乌江流域的自然、社会、经济条件,从五个方面分析流域梯级开发将产生的不良环境效应,并针对这些问题,提出了相应的防治对策。 相似文献
459.
J. C. Day 《Journal of the American Water Resources Association》1972,8(5):935-947
ABSTRACT. Despite radical differences in water laws, water management agencies, approaches to water planning, and financial resources, Mexico and the United States forged a common program to manage water and related land on the Rio Grande. Actions of Rio Grande Commissions related to stream gaging, boundary definition, and multiple-purpose construction projects are among the more successful international water-management efforts in the world. Cost-sharing arrangements promoted rapid completing of international works. However, joint action accomplished only part of expectations. International developments were competitive rather than complementary until basin water appropriation was virtually complete. Moreover, Commissions were not empowered to consider long-range competitive water needs, or regional water requirements, throughout the basin. International groundwater use coordination does not exist. International structures produce less than anticipated benefits. Hydroelectric generators are financial liabilities, irrigated acreage exceeds dependable streamflow, and soil salinization is experienced. Unanticipated environmental changes occurred in every major program. The Rio Grande experience points to the need for society to specify goals to which the use of water should contribute and to specify priorities for water use among different sectors of river basins and various segments of society. 相似文献
460.
在对辽宁省境内老哈河流域土壤侵蚀研究的基础上,通过计算泥沙迁移时间确定了该流域基于栅格尺度的泥沙输移比的空间分布,最终获得该流域的产沙量,结果表明北部的老官地、哈拉道口、烧锅营子等地以及中南部河流两侧是流域内主要产沙源;选用坡度、植被盖度、土地利用类型、土壤可蚀性、距河流距离、基岩岩性等因子,建立了老哈河流域泥沙供给的数学模型,结果表明流域产沙主要与坡度、距河流距离、土地利用类型和植被盖度密切相关。因此,改变土地利用类型、提高植被盖度是防治流域致灾泥沙的关键因素。本研究对今后老哈河流域土地利用规划及泥沙治理具有一定的指导意义。 相似文献