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81.
洞庭湖流域分布式水文模型   总被引:1,自引:0,他引:1  
流域出口径流观测序列是水文模型参数率定重要依据,不受水文站控制区域的模型应用是水文研究关注点之一。首先根据水文站观测资料建立洞庭湖流域四水控制站之上基于水文响应单元的分布式水文模型,在此基础上结合实验、同质移植和虚拟水库等方法,将分布式水文模型拓展到包含无径流站控制区域的丘陵区间和平原圩垸区,最终实现了洞庭湖全流域水文过程模拟。结果表明:在较完备土壤、地形、土地利用等空间数据支持下,通过合理的流域划分和水文响应单元定义,建立的流域分布式水文模型可以较好地在水文响应单元尺度反应降水发生后蒸散、地表径流、土壤和地下水的响应特征。而基于观测实验及基流分割等方法获取的关键水文过程特征对模型参数优化的认识,可以提高模型参数率定效率,在较少优化迭代运算后既可使月径流模拟的效率系数NSE和确定性系数R2值高于0.81(日过程高于0.62)。借助参数同质移植和虚拟水库解决了区间和圩垸区无控制站区域水文过程模拟。在全流域水文过程的模拟中,基流指数和蒸散比例与实际过程具有较好的一致性。说明相关参数较好地反映了其物理机制,具备在相似气候及下垫面条件区域进行同质移植的基础,圩垸区径流交换采用虚拟水库的处理方式也合理可行。  相似文献   
82.
Mishra V  Fuloria S  Bisht SS 《Disasters》2012,36(3):382-397
The focus of most disaster management programmes is to deploy resources-physical and human-from outside the disaster zone. This activity can produce a delay in disaster mitigation and recovery efforts, and a consequent loss of human lives and economic resources. It may be possible to expedite recovery and prevent loss of life by mapping out disaster proneness and the availability of resources in advance. This study proposes the development of two indices to do so. The Indian census data of 2001 is used to develop a methodology for creating one index on disaster proneness and one on resourcefulness for administrative units (tehsils). Findings reveal that tehsil residents face an elevated risk of disaster and that they are also grossly under-prepared for such events. The proposed indices can be used to map regional service provision facilities and to assist authorities in evaluating immediate, intermediate, and long-term disaster recovery needs and resource requirements.  相似文献   
83.
ABSTRACT Results of a field survey designed to assess the extent of crop production losses due to inadequate drainage in a large watershed of Iowa is presented. Information on the current status of drainage of the watershed, located in the Des Moines River basin, was collected through personal interviews with 256 farmers from 60 legal drainage districts. The results of the survey indicate that 95 percent of the area in upper Des Moines River basin has inadequate district mains or main outlet drains currently having a design capacity of ≤ 0.64 cm/day drainage coefficient. Outlet capacity of 1.27 cm/day d.c. would be required for full production. Inadequate drainage in the watershed is currently responsible for crop yield reduction equal to about one-third of the maximum yield potential for average weather conditions.  相似文献   
84.
ABSTRACT: A basic problem in the management of rivers has been how to balance the tradeoffs between instream and out-of-stream uses. Traditionally, the problem has been addressed by optimizing the economic benefits of flow diversions and regulated releases with instream uses as a flow constraint. An alternative method is to model the effect different river flows have on various recreational uses (e.g., boating, fishing) and then use the results as an additional function or piece of information to determine river project operations and benefits. A methodology that is based on multiobjective decision theory and that relates instream recreational preferences to river flow is proposed. The methodology consists of determining, standardizing, and combining recreational benefit functions, and incorporating potential sources of uncertainty into an estimate of total instream benefits. Thus different types of flow patterns, resulting from reservoir regulation (out-of-stream water uses), can be analyzed to determine their potential instream impact. The methodology is applied to the New River Gorge, West Virginia, which has been designated as a National River.  相似文献   
85.
ABSTRACT: The Louisiana Environmental Management System (LEMS) is a data processing program developed to aid the Louisiana Joint Legislative Committee on Environmental Quality in decisions leading to resources legislation. Serving as a central data collection and retrieval point for various agencies, the LEMS will maintain assembled information on the location of monitoring stations and coordinate the files of user agencies with data on: land use; air and water quality; meteorological, climatological, and hydrological phenomena; vegetation; fish and wildlife conservation; population; and economics. This data is geographically stored in relation to the state plane coordinate system. For decision making, all pertinent hydrologic, topographic, engineering, cadastral, and other information from separate sources can be automatically mapped as a combined overlay to one of three chosen scales. Land-use patterns are the input data for iterative analyses of present conditions and simulated future human activities for assessing the environmental impact of proposed multiple-purpose water resource developments.  相似文献   
86.
与水、大气污染相比,土壤污染具有隐蔽性、滞后性、累积性等特点,污染土壤治理恢复成本高、周期长、难度大,需要强化源头防控,防患于未然。简述了我国土壤污染重点监管单位的管理要求,从环境准入期、施工期、运营期和退役期4个环节梳理了重点监管单位的管理要点,分析了江苏省土壤污染重点监管单位的管理现状和存在问题,并从强化宣传培训,实施分类分级管理,探索开展边生产边管控技术模式,提升基层监管能力等方面提出了对策建议,以期为江苏省土壤环境管理工作提供决策参考。  相似文献   
87.
王园  袁增伟  毕军  张玲  刘凌轩 《环境科学研究》2009,22(10):1231-1236
以某农药集团草甘膦生产工艺为例,运用工业代谢分析方法对其水资源代谢过程进行量化分析,建立了水代谢平衡账户并绘制了水代谢图,在此基础上,识别和筛选出草甘膦生产过程中的主要用水单元及废水排放单元,并据此提出优化建议. 结果表明,草甘膦生产过程中的主要用水类别为蒸汽,其蒸汽消耗单元多且用汽量大,而换热网络单一,冷凝水浪费较严重,系统中水资源重复利用水平较差.针对该问题,从系统优化和节水管理等方面提出了工艺废水的重复利用及主要用汽单元之间的换热网络优化等建议,以期提高生产过程中的水资源利用效率.   相似文献   
88.
ABSTRACT: In an effort to adopt more holistic ecosystem approaches to resource assessment and management, many state and federal agencies have begun using watershed or ecoregion frameworks. Although few would question the need to make this move from dealing with problems and issues on a case by case or point-type basis to broader regional contexts, misunderstanding of each of the frameworks has resulted in inconsistency in their use and ultimate effectiveness. The focus of this paper is on the clarification of both frameworks. We stress that the issue is not whether to use watersheds (or basins or hydrologic units) or ecoregions for needs such as developing ecosystem management and non-point source pollution strategies or structuring water quality regulatory programs, but how to correctly use the frameworks together. Definitions, uses, and misuses of each of the frameworks are discussed as well as ways watersheds and ecoregions can be and have been used together effectively to meet resource management needs.  相似文献   
89.
介绍了中国石化炼化装置在使用固定式气体报警器过程中存在的主要问题,提出几点优化方案。  相似文献   
90.
通过对国内现有加氢裂化装置生产工艺和设备、资源和能源利用、污染物产生等情况的调查统计及分析,同时参考石油炼制业清洁生产指标评价体系,构建了加氢裂化装置清洁生产指标体系,为加氢裂化装置清洁生产审核和环境影响评价工作提供参考。  相似文献   
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