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891.
Wen‐Cheng Huang Tung‐Hsin Chang Fu‐Ti Yang 《Journal of the American Water Resources Association》2001,37(5):1279-1289
ABSTRACT: The objective of this paper is to examine a deficit in water for the Hsinchu area, the location of Taiwan's “Silicon Valley.” The methods suggested in this paper to diagnose water shortage problems are simple and practical. The results show that Hsinchu is in an area without sufficient water to meet demand for domestic and industrial uses. Until the completion of the Baoshan II Reservoir in 2006, the most feasible options for the Taiwan Water Supply Corporation to offset the water deficiency in Hsinchu City over the next five years are: (a) to obtain water gratuitously from the southern Yungheshan Reservoir; (b) to import additional water at an extra charge from other sources such as the northern Shihmen Reservoir and the agricultural sector; and (c) to conduct a comprehensive water conservation program at the Hsinchu Science‐based Industrial Park. 相似文献
892.
Mahesh Kumar Sahu Ashim Das Gupta 《Journal of the American Water Resources Association》2001,37(3):675-684
ABSTRACT: Operation of a storage‐based reservoir modifies the downstream flow usually to a value higher than that of natural flow in dry season. This could be important for irrigation, water supply, or power production as it is like an additional downstream benefit without any additional investment. This study addresses the operation of two proposed reservoirs and the downstream flow augmentation at an irrigation project located at the outlet of the Gandaki River basin in Nepal. The optimal operating policies of the reservoirs were determined using a Stochastic Dynamic Programming (SDP) model considering the maximization of power production. The modified flows downstream of the reservoirs were simulated by a simulation model using the optimal operating policy (for power maximization) and a synthetic long‐term inflow series. Comparing the existing flow (flow in river without reservoir operation) and the modified flow (flow after reservoir operation) at the irrigation project, the additional amount of flow was calculated. The reliability analysis indicated that the supply of irrigation could be increased by 25 to 100 percent of the existing supply over the dry season (January to April) with a reliability of more than 80 percent. 相似文献
893.
为了揭示悬浮泥沙(SSC)对水库水质的影响规律,对汾河水库进行样品收集和长期水质监测,采用水动力模型与泥沙转移和富营养化模型相结合的方法,将这三者关联耦合,并通过实测数据对模型进行参数率定和验证,分析含沙水和不含沙水中总氮(TN)、总磷(TP)、叶绿素a(Chla)、溶解氧(DO)四项指标,得出两者对水质造成的影响。结果表明:SSC对TN、TP的去除作用明显,对Chla、DO浓度分布影响较小,并计算了污染物的释放量以及贡献率,得出TP的负荷仅为16.47t,而贡献率高达25.25%。因此在汾河的污染控制方面应侧重削减磷,进而改善汾河地区的污染现状。 相似文献
894.
兴修大中型水利水电工程不可避免地要征收大量农田,造成大量移民非自愿性搬迁.我国实行开发性移民的方针,强调农村移民主要采取农业安置的策略.然而,移民的迁入势必会对安置区居民的土地权益带来负面的影响.因此,根据"卡尔多-希克斯"社会福利改进标准,要实现安置区土地向移民转移过程的社会福利改进,需要对利益受损的安置区集体和居民给予相应的补偿以弥补其福利损失.本文以湖北省竹山县潘口水电站为例,在对竹山县溢水镇、宝丰镇两个乡(镇)5个移民安置点的73户安置区居民进行问卷调查的基础上,运用条件价值法(CVM)对安置区土地流转的补偿标准进行了实证研究,研究结果表明:潘口水电站移民安置区土地流转补偿执行标准均未达到农地实际价值的一半,水田的补偿程度为49.54%.旱地的补偿程度为为44.54%,安置区集体和居民没有获得充分的补偿,因此,需要提高安置区土地流转补偿标准,使安置区居民也能和移民一样地分享到水利水电工程带来的增值收益. 相似文献
895.
东平湖库区可持续发展综合分析 总被引:3,自引:0,他引:3
东平湖库区人口、资源及环境的矛盾非常突出,贫困与生态环境恶化的双重压力严重制约了库区的可持续发展。本文用可持续发展的观点及理论分析了库区可持续发展的客观因素,并对库区可持续发展的措施进行了探讨。 相似文献
896.
王洪起 《城市环境与城市生态》1993,6(2):42-46
本文论述了于桥水库大型水生植物的现状、作用、管理和保护对策及管理和利用中存在的问题.建议:不要盲目地在库中投放大量草鱼; 6月份以前应对大型水生植物实施保护性措施; 8月初开始应尽量多地收割和捞出大型水生植物.同时应加强6~7月份库中大型水生植物管理方案的研究和大型水生植物二次利用的研究. 相似文献
897.
三峡库区农村移民城镇安置刍论 总被引:3,自引:2,他引:1
杨定国 《长江流域资源与环境》1995,4(3):209-215
移民安置尤其农村移民安置是大型水利和水电工程普遍遇到一个复杂的大问题,关系工程成败命运。三峡工程移民数量巨大,安置任务繁重艰巨。农村移民城镇安置,具有可靠性大和稳定度高特点,应是三工程移民安置的重要途径。经库区城镇发展程度和农村移民素质适合城镇非农就业数量状况双重分析结果,三峡库区农村移民的城镇安置比重至少可达45-50%,可望争取达到60-70%。 相似文献
898.
Deborah Ulinski Potter Judy L. Meyer 《Journal of the American Water Resources Association》1982,18(4):635-642
ABSTRACT: Zooplankton colonization was followed for 16 months in Lake Oconee, Georgia, a new pumped storage reservoir. Data were interpreted to identify differences among stations and seasons, as a function of the reservoir's early stage of development and of pumped storage operations. Colonization was rapid, and the zooplankton community was characterized by a high species diversity; approximately 40 rotifer species and 14 cladoceran genera were recorded. Zooplankton density varied along an environmental gradient from riverine to lentic conditions. Rotifer abundance varied from 104-106 individuals/m3, with maxima in the summers Copepod and cladoceran densities ranged from 103 to nearly 105 individuals/m3; maxima for stations other than the dam were observed in the summer and early fall, but high values at the dam station occurred throughout winter 1980. When pumped storage operations began in December 1979, zooplankton densities increased at the dam station. Pumpback decreased the intensity of the environmental gradient from riverine to lentic conditions, and led to a more similar zooplankton community structure throughout the reservoir. 相似文献
899.
Ted L. Napier Silvana M. Camboni W. Richard Goe 《Journal of the American Water Resources Association》1986,22(1):11-18
ABSTRACT: Data were collected from residents of a rural community at two time periods to assess attitudes toward uses made of a reservoir which had been recently constructed in the area. The findings revealed that attitudes became significantly more favorable for flood control, water supply, and recreation uses of the reservoir. Attitudes toward fish and wildlife conservation use were not significantly different over time but these uses were perceived positively at both time periods. The data were also analyzed in the context of a vested interest perspective using cross-sectional design. The findings demonstrated that the theoretical model used to guide the investigation was quite useful in predicting attitudes toward the four uses examined. 相似文献
900.
Within the past few years, a number of papers have been published in which stochastic mathematical programming models, incorporating first order Markov chains, have been used to derive alternative sequential operating policies for a multiple purpose reservoir. This paper attempts to review and compare three such mathematical modeling and solution techniques, namely dynamic programming, policy iteration, and linear programming. It is assumed that the flows into the reservoir are serially correlated stochastic quantities. The design parameters are assumed fixed, i.e., the reservoir capacity and the storage and release targets, if any, are predetermined. The models are discrete since the continuous variables of time, volume, and flow are approximated by discrete units. The problem is to derive an optimal operating policy. Such a policy defines the reservoir release as a function of the current storage volume and inflow. The form of the solution and some of the advantages, limitations and computational efficiencies of each of the models and their algorithms are compared using a simplified numerical example. 相似文献