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301.
Wildman, Richard A., Jr. and Noelani A. Forde, 2012. Management of Water Shortage in the Colorado River Basin: Evaluating Current Policy and the Viability of Interstate Water Trading. Journal of the American Water Resources Association (JAWRA) 48(3): 411-422. DOI: 10.1111/j.1752-1688.2012.00665.x Abstract: The water of the Colorado River of the southwestern United States (U.S.) is presently used beyond its reliable supply, and the flow of this river is forecast to decrease significantly due to climate change. A recent interim report of the Colorado River Basin Water Supply and Demand Study is the first acknowledgment of these facts by U.S. federal water managers. In light of this new stance, we evaluate the current policy of adaptation to water shortages in the Colorado River Basin. We find that initial shortages will be borne only by the cities of Arizona and Nevada and farms in Arizona whereas the other Basin states have no incentive to reduce consumptive use. Furthermore, the development of a long-term plan is deferred until greater water scarcity exists. As a potential response to long-term water scarcity, we evaluate the viability of an interstate water market in the Colorado River Basin. We inform our analysis with newly available data from the Murray-Darling Basin of Australia, which has used interstate water trading to create vital flexibility during extreme aridity during recent years. We find that, despite substantial obstacles, an interstate water market is a compelling reform that could be used not only to adapt to increased water scarcity but also to preserve core elements of Colorado River Basin law.  相似文献   
302.
Zorn, Troy G., Paul W. Seelbach, and Edward S. Rutherford, 2012. A Regional‐Scale Habitat Suitability Model to Assess the Effects of Flow Reduction on Fish Assemblages in Michigan Streams. Journal of the American Water Resources Association (JAWRA) 48(5): 871‐895. DOI: 10.1111/j.1752‐1688.2012.00656.x Abstract: In response to concerns over increased use and potential diversion of Michigan’s freshwater resources, and the resulting state legislative mandate, an advisory council created an integrated assessment model to determine the potential for water withdrawals to cause an adverse resource impact to fish assemblages in Michigan’s streams. As part of this effort, we developed a model to predict how fish assemblages characteristic of different stream types would change in response to decreased stream base flows. We describe model development and use in this case study. The model uses habitat suitability information (i.e., catchment size, base‐flow yield, and July mean water temperature) for over 40 fish species to predict assemblage structure in an individual river segment under a range of base‐flow reductions. By synthesizing model runs for individual fish species at representative segments for each of Michigan’s 11 ecological stream types, we developed curves describing how typical fish assemblages in each type respond to flow reduction. Each stream type‐specific, fish response curve was used to identify streamflow reduction levels resulting in adverse resource impacts to characteristic fish populations, the regulatory standard. Used together with a statewide map of stream types, our model provided a spatially comprehensive framework for evaluating impacts of flow withdrawals on biotic communities across a diverse regional landscape.  相似文献   
303.
Critical subset allocation (CSA) is a methodology for allocating remediation costs at sites where multiple contaminants contribute to the exceedance of multiple regulatory risk standards. The basic unit of allocation in CSA is the critical subset, which is a subset of potentially responsible parties (PRPs) that meets two criteria: 1) the risks associated with the subset exceed at least one regulatory risk standard; and 2) at least one of the PRPs in the subset is individually necessary for the first criterion to be true. Each PRP is assigned an allocation score equal to the number of critical subsets for which that PRP is an individually necessary member. The allocation share of a PRP is equal to its allocation score divided by the sum of all PRP allocation scores.  相似文献   
304.
排污权的合理定价可以为环境保护提供正确的经济激励,引导排污企业将污染排放量设定在社会的最优水平。从理论上分析了排污权定价时应综合考虑的影响因素,构建了排污权定价模型的指标体系;运用主成分分析法和客观赋值法,从地区因素、污染物因素和行业因素3方面附加权重计算排污权基准价定价模型的价格系数,为排污权合理定价提供参考。  相似文献   
305.
《Environmental Forensics》2013,14(4):245-253
This article provides context for the ensuing three-part study published in this volume that describes quantitative allocation of mass metal loading to the 20 km groundwater plume in the Pinal Creek alluvial aquifer. The plume resulted from >75 years of copper ore leaching by ferric sulfate and sulfuric acid in the Globe-Miami mining district, Arizona. Geochemical fingerprinting, followed by spatial and temporal analysis of Pinal Creek monitoring well data, identified three distinct source areas and plumes. Each exhibited a unique chlorine-copper-iron chemical signature that resulted from differences in process geochemistry, ore mineralogy, and solution handling. As the acid plume advanced, carbonate buffering capacity was consumed, with concomitant precipitation of metal oxyhydroxides that evolved into acid-bearing aluminum and iron cements. Column experiments, geochemical modeling, and empirical data indicate that dissolution of the residual acidic precipitates will result in asymptotic reductions in metal concentrations, which will affect response costs for up to 140 years after initiation of remedial pumping in the late 1980s. Finally, metal loading to the alluvial aquifer was quantified for each source area using Darcy's Law or flow data combined with the sum of aluminum, copper, iron, manganese, and zinc, which constitute >99% of the total metal mass. Based on this analysis, to date Webster Gulch contributed 94% of the loading, Upper Bloody Tanks Wash contributed 5%, and the Miami Unit contributed 1%. A sensitivity analysis that varied all parameters in the loading calculation by ±20% resulted in only small differences in allocation (±1%) because the large mass released from Webster Gulch (618 kt of metal) dominates the overall allocation.  相似文献   
306.
I describe siblicide in the laughing kookaburra (Dacelo novaeguineae), a reverse size-dimorphic, cooperatively breeding kingfisher. Clutches were usually of three eggs, and nestlings hatched asynchronously, with intervals of 2–72 h between successive eggs. Siblicide occurred in two temporally and mechanistically distinct episodes. The youngest nestling died in one-third of all nests within days of hatching as a result of aggression from its elders. Kookaburra nestlings attacked each other using a hook on their upper beak – a rare example of a morphological specialisation for sibling rivalry. In one-fifth of all nests, the youngest nestling starved to death much later, without overt aggression, when nestling growth rates were highest. I examined the effects of food availability and competitive disparities between nestlings on the incidence of both types of siblicide. The probability of late, starvation-mediated mortality was negatively correlated with the number of male helpers. Early, aggressively mediated siblicide occurred in nests characterised by a suite of correlated variables that I call the ”kookaburra siblicide syndrome”: (1) no male helpers attended the nest, (2) the third-hatched nestling was much smaller than the second-hatched nestling, (3) the first and second nestling to hatch were male and female, respectively, and (4) there was a short hatch interval between the first two nestlings. The kookaburra siblicide syndrome variables could be inter-correlated if they were all related to the female’s condition at the onset of incubation. Females in poorer condition may be less likely to have male helpers, more likely to lay small third eggs, and more likely to hatch the first two eggs relatively synchronously because of nutritional constraints during the onset of incubation. These females may further promote siblicide by modifying the sexes of the first two nestlings. If a female hatches soon after an older but eventually smaller brother, dominance between the first two nestlings could be destabilised. I suggest this leads to escalated aggression in the nest and the death of the third nestling, which is least able to defend itself. Received: 17 December 1999 / Received in revised form: 8 May 2000 / Accepted: 20 May 2000  相似文献   
307.
突发事故下应急资源优化配置定量模型研究   总被引:4,自引:0,他引:4  
以提高城市的应急管理能力为目标,针对突发事故灾害应急管理的特点,根据应急点的数目,将应急资源配置过程划分为若干阶段.以每一阶段开始或上一阶段结束时已调度的应急资源数量为状态变量,结合动态规划的基本理论,构建应急资源优化配置数学模型,并通过案例分析对该模型的实用性和有效性进行验证.结果表明,基于动态规划理论的应急资源优化配置定量模型可以避免传统管理模式下应急资源配置过程中的重复、缺项以及资源利用低效等问题,能有效指导应急过程中应急资源的优化配置,提高突发事故下城市的整体应急能力.  相似文献   
308.
随着宁夏引扬黄灌区经济的发展,建立一种新的水权分配模式势在必行。论文首先根据水权初始分配有效性、公平性与可持续性的原则,建立了水权初始分配指标体系,并构造了层次结构模型。然后,利用标度转化法,将互反性的"1~9标度"转化为互补性的"0.1~0.9九标度,"再利用后者与指标体系建立模糊互补判断矩阵,并对该矩阵进行模糊层次分析,从而将模糊层次分析法(FAHP)引入到了初始水权分配领域。最后,应用FAHP法对宁夏灌区的初始水权进行分配,获得了较为满意的结果。  相似文献   
309.
广东省人为源大气污染物排放清单及特征研究   总被引:24,自引:9,他引:24  
本研究根据收集的广东省人为源活动水平数据,采用合理的估算方法、排放因子和GIS技术,建立了该地区2010年3 km×3 km人为源大气污染物排放清单.结果显示,2010年广东省SO2、NOx、CO、PM10、PM2.5、BC、OC、VOCs和NH3排放总量分别为867.8×103、1607.0×103、7476.0×103、1397.6×103、633.2×103、50.5×103、98.3×103、1436.5×103和578.3×103t.固定燃烧源是SO2和NOx的最大排放贡献源,CO排放主要来自道路移动源、固定燃烧源和生物质燃烧源,扬尘源和工业过程源是主要的PM10和PM2.5排放源,生物质燃烧源是最大的BC和OC贡献源,VOCs排放主要来自有机溶剂使用源、道路移动源和工业过程源,NH3排放主要来源于畜禽养殖和氮肥施用.东莞、佛山和广州是主要的SO2、NOx、CO和VOCs排放城市,广州、清远和梅州是最主要的PM10和PM2.5排放城市,BC排放集中在广州、深圳、东莞、佛山等珠三角城市,OC的重要排放城市为湛江和茂名,NH3排放主要分布在茂名、湛江和肇庆.空间分布结果显示,广东省NH3排放高值区分布在粤西和粤东地区,其他污染物排放高值区则主要分布在珠三角城市群.本研究建立的排放源清单仍具有一定的不确定性,建议后续研究加强大气污染源排放的基础研究,进一步完善该地区的排放源清单,以期为区域大气污染预报预警和污染控制措施的制定提供重要基础数据.  相似文献   
310.
以杭州市全市域为研究对象,基于机动车排放管理数据库和IVE模型本地化后计算出市区、城区、城郊和郊区4类区域及快速路、主干路和次干路3类道路的各类机动车排放清单,利用Arc GIS及杭州市路网信息建立了1 km×1 km网格化空间分布,分析了机动车污染物排放特征.结果显示,杭州市机动车各污染物NO_x、CO、PM_(2.5)和VOCs的年排放量分别为4.9×10~4、12.5×10~4、0.2×10~4、2.1×10~4t.各种车型中,中重型货车对NO_x和PM_(2.5)的贡献均最大,分别为45.8%和36.3%,其次为大中型客车、公交客运,小微型客车对CO和VOCs的排放贡献最大,分别为69.3%和51.1%.机动车各污染物排放强度均呈现由城市中心向城市边缘递减的趋势,高排放区域集中在城中心及城南和城北区域,同时各污染物排放量日变化特征明显,均出现弱双峰现象.  相似文献   
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