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981.
森林土壤有机层生化特性及其对气候变化的响应研究进展 总被引:8,自引:0,他引:8
森林土壤有机层是指累积在土壤表面未分解到完全分解的有机残余物质,在全球碳循环中具有十分重要的作用和地位.目前有关森林土壤有机层的生态研究主要集中于土壤有机层的凋落物储量、水土保持功能、生物多样性保育功能及其生化特性等,而有关其对气候变化响应的研究报道还相当少见,且已有的研究主要关于土壤有机层的碳源/汇动态等,有关森林土壤有机层生化特性对气候变化响应的研究还相对较少,这与其在全球气候变化中的作用和地位是极不相称的.过去10a中,有关土壤有机层生化特性对气候变化响应的研究主要包括土壤有机层的微生物数量、微生物生物量、呼吸作用、有机物质分解动态(凋落物分解)、酶活性等对环境变化的响应等方面.进一步的控制实验研究被认为是相当重要的.参51 相似文献
982.
JAY R. MALCOLM†† CANRAN LIU† RONALD P. NEILSON‡ LARA HANSEN§ LEE HANNAH 《Conservation biology》2006,20(2):538-548
983.
Mortality Gradients within and among Dominant Plant Populations as Barometers of Ecosystem Change During Extreme Drought 总被引:7,自引:0,他引:7
984.
MARIANNE R. FISH†‡ ISABELLE M. CÔTɆ† JENNIFER A. GILL†‡ REW P. JONES†‡ SASKIA RENSHOFF§ ANDREW R. WATKINSON†‡ 《Conservation biology》2005,19(2):482-491
Abstract: The projected rise in sea level is likely to increase the vulnerability of coastal zones in the Caribbean, which are already under pressure from a combination of anthropogenic activities and natural processes. One of the major effects will be a loss of beach habitat, which provides nesting sites for endangered sea turtles. To assess the potential impacts of sea-level rise on sea turtle nesting habitat, we used beach profile measurements of turtle nesting beaches on Bonaire, Netherlands Antilles, to develop elevation models of individual beaches in a geographic information system. These models were then used to quantify areas of beach vulnerable to three different scenarios of a rise in sea level. Physical characteristics of the beaches were also recorded and related to beach vulnerability, flooding, and nesting frequency. Beaches varied in physical characteristics and therefore in their vulnerability to flooding. Up to 32% of the total current beach area could be lost with a 0.5-m rise in sea level, with lower, narrower beaches being the most vulnerable. Vulnerability varied with land use adjacent to the beach. These predictions about loss of nesting habitat have important implications for turtle populations in the region. 相似文献
985.
本文在对信宜县山区农业气候资源进行深入研究分析的基础上,根据各种蔬菜的生物学特性,提出了信宜县山区露地种植反季节蔬菜的适宜海拔高度和栽培措施,为广东省山区合理利用垂直气候资源,发展反季节蔬菜生产提供了科学依据。 相似文献
986.
Agricultural adaptation to climate change in China 总被引:4,自引:0,他引:4
YOU Song-cai 《环境科学学报(英文版)》2001,13(2):192-197
IntroductionAdaptationreferstoeffortstoreducesystem’svulnerabilitiestoclimate.Amongthemostfrequentlycitedhumansystemslikelytobeaffectedbyclimaticchangeisagriculture.Itisespeciallysensitivetotheconsequencesofglobalwarmingasitreliesheavilyontheweatheran… 相似文献
987.
988.
Preliminary analysis based on an aggregate model of global carbon emissions suggests that constraining emissions to the levels that would be imposed by compliance with the results of the Kyoto negotiations can increase the discounted cost of ultimately limiting atmospheric concentrations. Kyoto targets can be either too restrictive or too permissive depending upon the (currently unknown) trajectory of carbon emissions over the near- to medium-term and the (as yet unspecified) concentration target that frames long-term policy. The discounted cost of meeting low concentration targets like 450 ppmv. is diminished by allowing large sinks and/or by imposing more restrictive near-term emissions benchmarks (even if only Annex B countries are bound by the Kyoto accord). Conversely, the cost of achieving high concentration targets like 650 ppmv. is diminished by disallowing sinks and/or by imposing less restrictive emissions benchmarks. Intermediate concentration targets like 550 ppmv. look like high concentration targets (favoring no sinks and expanded near-term emissions) along low emissions paths; but they look like low concentration targets (favoring the opposite) along high emissions paths. Emissions trajectories that lie above the median, but not excessively so, represent cases for which adjustments in the Kyoto emissions benchmarks and/or negotiated allowances for sinks have the smallest effect on the cost of mitigation. 相似文献
989.
In this paper, an investigation of simulated monthly precipitations from April to September is made. Though the precipitations are sometimes overestimated or underestimated, the geographical advance and recession of precipitation zones are well simulated by the UKMO global climate model with a simple mixed-layer ocean. Main characteristics of large-scale precipitation distribution are changed less on CO2-doubling, but the change is significant in some regions. The change in precipitation threatens us while the dry region is imposed by rainfall defect or the wet region by abundant rainfall induced by CO2-doubling. 相似文献
990.
Active Amplification of the Terrestrial Albedo to Mitigate Climate Change: An Exploratory Study 总被引:1,自引:0,他引:1
Robert M. Hamwey 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):419-439
To date, international efforts to mitigate climate change have focussed on reducing emissions of greenhouse gases in the energy,
transportation and agriculture sectors, and on sequestering atmospheric carbon dioxide in forests. Here, the potential to
complement these efforts by actions to enhance the reflectance of solar insolation by the human settlement and grassland components
of the Earth's terrestrial surface is explored. Preliminary estimates derived using a static two dimensional radiative transfer
model indicate that such efforts could amplify the overall planetary albedo enough to offset the current global annual average
level of radiative forcing caused by anthropogenic greenhouse gases by as much as 30% or 0.76 Wm− 2. Terrestrial albedo amplification may thus extend, by about 25 years, the time available to advance the development and use
of low-emission energy conversion technologies which ultimately remain essential to mitigate long-term climate change. While
a scoping analysis indicates the technical feasibility of sufficiently enhancing human settlement and grassland albedos to
levels needed to achieve reductions in radiative forcing projected here, additional study is required on two fronts. Firstly,
the modelled radiative forcing reductions are static estimates. As they would generate climate feedbacks, more detailed dynamic
climate modelling would be needed to confirm the stationary value of the radiative forcing reduction that would result from
land surface albedo amplification. Secondly, land surface albedo amplification schemes may have important economic and environmental
impacts. Accurate ex ante impact assessments would be required to validate global implementation of related measures as a viable mitigation strategy. 相似文献