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91.
雄安新区是千年大计、国家大事,水资源短缺与水体污染成为制约其发展的主要问题。从水资源利用效率及节水潜力视角出发,以深圳发展历程为标杆,结合情景分析与方向性距离函数等模型,展示到2035年不同情景的雄安水资源利用效率及节水潜力发展图景和路径。研究表明:从利用效率看,在基准、起步、建成情景下雄安呈现出由低效率区到较高效率区再到高效率区的变化态势。从节水潜力看,效率改善空间减小、技术落差比增加等表明雄安节水潜力得到充分挖掘。杜绝污水直排、积极发展污水处理技术、优化新区产业结构等是促使水资源利用效率提高的有效手段,是雄安实现绿色生态发展的重要保障。  相似文献   
92.
Intrusive agricultural experimentspublished in New Zealand in the last five yearsare reviewed in terms of the degree of animalsuffering involved, and the necessity for thissuffering in relation to research findings.When measured against animal welfare criteriaof the Ministry of Agriculture, thirty-sixstudies inflicted ``severe' or ``very severe'suffering. Many of these experiments hadquestionable short-term applications, had anapplication restricted to agriculturalproduction or economic growth, or could havebeen modified to prevent or reduce suffering.  相似文献   
93.
The method of anthropoecological landscape stability (AELS) has been applied experimentally to a territorial unit, forming a closed watershed with more of less precisely defined material, energy, and population flows. This article presents data-driven results of monitoring and conclusions on optimizing features derived from two object-oriented expert systems—the FORELIS, giving heuristically optimal conditions for forest compositions on the site in the prevailing immission situation, and AGRILIS—the agricultural expert system having the scope of finding suitable forms of agriculture with respect to natural conditions and suitable actual production facilities. The results of the study fully confirmed the feasibility of applying expert systems to actual conditions, and no significant errors in the results of the expert systems compared to indications by monitoring have been disclosed.  相似文献   
94.
Treated wastewater from a food-processing plant, together with intermittent outflow from a hypereutrophic pond, were discharged over a 20-year period to a cattail-dominated wetland and hence to a small stream. Organics and nutriet levels in the effluent were comparable to levels in domestic wastewater. Fifteen variables were monitored upstream and downstream from the plant over 18 months. Means for most variables were slightly higher downstream, but differences between stations were not statistically significant. Wetland processing of nitrogen was markedly affected by a change from drought to flood conditions. After accounting for dilution, the overall effect of the wetland on the effluent was to reduce biological oxygen demand 43.7%, ammonia N 46.3%, nitrate/nitrite N 17.4%, and conductivity 15.6%. However, total suspended solids were increased 41.4%, total organic nitrogen 28.8%, and total phosphorus 24.7%. It was concluded that the wetland effectively renovated the effluent but the removal efficiency would be improved if the effluent were pretreated to reduce phosphorus and dispersed to increase residence time in the wetland.  相似文献   
95.
Disposal of sewage sludge in the New York Bight Apex (12-Mile Dump Site) ceased at the end of December 1987. Previous efforts to quantify the effects of sludge were hindered by the inability to obtain true replication. the cessation of dumping afforded the opportunity to apply the technique of replication in time, also known as a Before/After, Control/Impact design. Conditionally, this method allows one to separate treatment effects from the natural differences that confound many environmental impact studies. the Environmental Processes Division of the Northeast Fisheries Center, National Marine Fisheries Service sampled the benthic environment of the New York Bight Apex from June 1986 through September 1989 using a sample design based on the technique of replication in time.

Three dominant species (rock crab, Cancer irroratus; little skate; Raja erinacea; and winter flounder, Pseudopleuronectes americanus) and total demersal finfish, collected by otter trawl, showed no statistically significant response to the cessation of disposal. American lobster (Homarus americanus) increased in local abundance, but this result was possibly confounded by a change in fishing effort.  相似文献   
96.
ABSTRACT: Flow-duration curves are concise pictures of flow variability at a point on a stream, and provide essential information for all water-resource planning. In New Hampshire, useful estimates of flow-duration curves for ungaged points on unregulated streams can be made using only information readily available from contour maps: 1) area of the basin above the point of interest; and 2) either the measured mean basin elevation or the elevations of the highest and lowest points in the basin. Measured or estimated mean basin elevation is then used in regression equations to estimate mean flow QC and the flow exceeded 95% of the time, Q95. QC is assumed to occur at the 27% exceedance frequency. Q02, Q05, and Q30 are estimated as multiples of QC. Equations are provided for calculating 95% confidence intervals for future estimates using the method. The dependence of mean flow on elevation is due to positive vertical precipitation gradients and negative vertical evapotranspiration gradients. The dependence of Q95 on elevation appears to be due largely to the fact that it rains more often, that snowmelt takes longer, and that evapotranspiration is reduced at higher elevations.  相似文献   
97.
The Clutha is the largest river in New Zealand. The last two decades have witnessed major conflicts centered on the utilization of the water resources of the upper Clutha river. These conflicts have by no means been finally resolved. The focus of this article is on institutional arrangements for water resource management on the Clutha, with particular reference to the decision-making processes that have culminated in the building of the high dam. It critically evaluates recent experiences and comments on future prospects for resolving resource use conflicts rationally through planning for multiple utilization in a climate of market led policies of the present government.The study demonstrates the inevitable conflicts that can arise within a public bureaucracy that combines dual responsibilities for policy making and operational functions. Hitherto, central government has been able to manipulate the water resource allocation process to its advantage because of a lack of clear separation between its two roles as a policy maker and developer. The conflicts that have manifested themselves during the last two decades over the Clutha should be seen as part of a wider public debate during the last two decades concerning resource utilization in New Zealand. The Clutha controversy was preceded by comparable concerns over the rising of the level of Lake Manapouri during the 1960s and has been followed by the debate over the think big resource development projects during the 1980s.The election of the fourth Labour government in 1983 has heralded a political and economic policy shift in New Zealand towards minimizing the role of public intervention in resource allocation and major structural reforms in the relative roles of central and regional government in resource management. The significance of these changes pose important implications for the future management of the Clutha.  相似文献   
98.
As green infrastructure gets its attention in hazard mitigation, it is necessary to improve general understanding on what makes green infrastructure important for hazard and resiliency research. To better understand how green infrastructure fits with more traditional notions of structural and nonstructural mitigation, this study examines the relationship between green infrastructure and ‘structural and nonstructural’ mitigation approaches for hazard mitigation. Also, this study discusses a new measurement of locational aspects and spatial patterns of green infrastructure by utilizing high-resolution data in urban areas, and its potential implementation in hazard mitigation. Compared to previous research using land-use land-cover datasets, the normalized difference vegetation index (NDVI) utilizing National Agriculture Imagery Program dataset provides an ability to capture green infrastructure in greater detail. A visual comparison suggests that the NDVI data are able to capture and identify more types of ‘green’ land uses in Harris County. The total green infrastructure percentages for Harris County, Texas, based on 1-m high resolution were found to be 61.5% of the area, compared to the 51.5% based on the National Land Cover Database. This study provides support for utilizing high-resolution data to establish guidelines for green infrastructure’s spatial characteristics and sustainable hazard mitigation. The outcomes of this study will be helpful in the strategic planning and implementation of green infrastructure in urban areas with hazard issues.  相似文献   
99.
As data sets of multiple types and scales proliferate, it will be increasingly important to be able to flexibly combine them in ways that retain relevant information. A case in point is Amazonia, a large, data-poor region where most whole-basin data sets are limited to understanding land cover interpreted through a variety of remote sensing techniques and sensors. A growing body of work, however, indicates that the future state of much of Amazonia depends on the land use to which converted areas are put, but land use in the tropics is difficult to assess from remotely sensed data alone. An earlier paper developed new snapshots of agricultural land use in this region using a statistical fusion of satellite data and agricultural census data, an underutilized ancillary data source available across Amazonia. The creation of these land-use maps, which have the spatial detail of a satellite image and the attribute information of an agricultural census, required the development of a new statistical technique for merging data sets at different scales and of fundamentally different data types. Here we describe and assess this nonlinear technique, which reinterprets existing land cover classifications by determining what categories are most highly related to the polygon land-use data across the study area. Although developed for this region, the technique appears to hold broad promise for the systematic fusion of multiple data sets that are closely related but of different origins. The figures in the printed version of this article appear in black and white. Color figures are available from the author upon request.  相似文献   
100.
ABSTRACT

This article, through the use of political ecology perspectives on coercive conservation, aims to explain how in two separate Colombian Natural Parks and buffer zones, environmental policies designed to (re)take control of the frontier, have produced a similar territorial differentiation in the contention of illicit activities. Los Farallones in the Colombian Pacific and La Macarena/Puerto Rico in the Ariari region have experienced different stages of the armed conflict and are at the center of this analysis. I argue that in the contexts of both conflict escalation (1998–2007) and conflict de-escalation (2008–2016), the State in its attempt to control the frontier has not only had military intervention in areas of conservation but has also reinforced environmental programs that attack illegal mining and coca, producing both a territorially differentiated containment of illicit activities and an uneven progression of the illicit frontier.  相似文献   
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