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251.
Montane Meadows as Indicators of Environmental Change 总被引:1,自引:0,他引:1
Diane M. Debinski Mark E. Jakubauskas Kelly Kindscher 《Environmental monitoring and assessment》2000,64(1):213-225
We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change 相似文献
252.
Claudia Pahl-Wostl Christoph Schlumpf Martin Büssenschütt Andreas Schönborn Jan Burse 《Integrated Assessment》2000,1(4):267-280
Within the CLEAR project a new approach to integrated assessment modelling has been developed for the participatory integrated
assessment of regional climate change involving citizens' focus groups. The climate change decision problem was structured
by focusing separately on climate impacts and mitigation options. The attempt was made to link the different scales of the
problem from the individual to the global level. The abstract topic of climate change was related to options on the level
of a citizen's individual lifestyle. The option of a low energy society was emphasised in order to embed the climate change
decision problem in a wider range of societal concerns. Special emphasis was given to the characterisation and communication
of uncertainties. The chosen approach allows different kinds of uncertainties in one framework to be addressed. The paper
concludes with a summary of the experience made, and recommendations for the use of models in participatory integrated assessments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
253.
Past changes and possible future variations in the nature of extreme precipitation and flood events in Central Europe and
the Alpine region are examined from a physical standpoint. An overview is given of the following key contributory physical
processes: (1) the variability of the large-scale atmospheric flow and the associated changes of the North-Atlantic storm
track; (2) the feedback process between climate warming and the water cycle, and in particular the potential for more frequent
heavy precipitation events; and (3) the catchment-scale hydrological processes associated with variations in major river flooding
events and that are related to land-use changes, river training measures, and shifts in the proportion of rain to snowfall.
In this context an account is provided of the possible future forecasting and warning methodologies based upon high-resolution
weather prediction and runoff models. Also consideration is given to the detectability of past (future) changes in observed
(modeled) extreme events. It is shown that their rarity and natural fluctuation largely impedes a detection of systematic
variations. These effects restrict trend analysis of such events to return periods of below a few months. An illustration
using daily precipitation from the Swiss Alps does yield evidence for pronounced trends of intense precipitation events (return
period 30 days), while trends of stronger event classes are not detectable (but nevertheless can not be excluded). The small
detection probability for extreme events limits possible mitigation of future damage costs through an abatement of climate
change alone, and points to the desirability of developing improved early forecasting/warning systems as an additional no-regret
strategy.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
254.
关于植物中氟化物测定结果的计算 总被引:1,自引:0,他引:1
针对植物中氟化物测定时由于绘制校准曲线的标准溶液体积与分析样品的定容体积不一样而引出的结果计算时的某些问题,提出了正确的计算方法和建议。 相似文献
255.
A. Veldkamp P.H. Verburg K. Kok G.H.J. de Koning J. Priess A.R. Bergsma 《Environmental Modeling and Assessment》2001,6(2):111-121
This paper introduces some of the issues that are relevant to the spatially explicit modeling of land use systems. A short overview is given of the ways and means in which a number of different land use change models describe the land use system. Specific attention is given to the empirical modeling approach used in the CLUE (Conversion of Land Use and its Effects) modeling framework. This approach is demonstrated for three case studies in China, Ecuador and the Atlantic Zone of Costa Rica. These case-studies illustrate the methodology for multi-scale analysis of land use driving factors and their application in spatially explicit modeling exercises. Model functioning, performance and limitations are discussed. The presented case-studies indicate that empirical modeling results can contribute to a better theoretic imbedding of land use change research in scale sensitive and integrated theories. 相似文献
256.
T. Stuczyiński G. Demidowicz T. Deputat T. Górski S. Krasowicz J. Kuś 《Environmental monitoring and assessment》2000,61(1):133-144
This paper demonstrates the ability of Polish agriculture to adapt to predicted climate change according to GISS and GFDL scenarios. Both climate-change scenarios will significantly affect farming conditions in Poland through water deficit, shifts in planting and harvesting seasons, changes in crop yields and crop structure. Neither scenario seems to endanger the self-sufficiency of Poland as long as preventative measures are taken. Moreover, the realization of GISS creates the possibility of a surplus in production. It must be emphasized that regardless of the scenario, the adaptation of agriculture to an expected climate change cannot be handled by the farming community itself. 相似文献
257.
258.
连云港市空气质量变化趋势分析 总被引:2,自引:0,他引:2
依据连云港市2002—2011年空气质量监测数据,对连云港市空气质量现状及其变化趋势进行系统的分析,并结合实际提出相应对策建议。结果表明,近年来连云港市空气质量总体良好,SO2浓度逐年下降,NO2浓度变化较平稳,PM10浓度下降显著。污染物浓度表现出明显的季节性特征,夏季浓度较低,春冬季较高;主城区各污染物浓度高于其他地区,但总体呈下降趋势。 相似文献
259.
Nathan L. Engle 《Journal of the American Water Resources Association》2012,48(6):1139-1150
Abstract: It is critical to understand the ability of water management to prepare for and respond to the likely increasing duration, frequency, and intensity of droughts brought about by climate variability and change. This article evaluates this ability, or adaptive capacity, within large urban community water systems (CWSs) in Arizona and Georgia. It analyzes interview data on the bridges and barriers to adapting water management approaches in relation to extreme droughts over the past decade. This study not only finds levers for building adaptive capacity that are unique to each state but also identifies several unifying themes that cut across both cases. The interviews also show that a particular bridge or barrier, such as state regulation, is not universally beneficial or detrimental for building adaptive capacity within each state. Such knowledge is useful for improving water and drought management and for understanding how CWSs might prepare for future climate variability and change by removing the barriers and bolstering the bridges in efforts to build adaptive capacity. 相似文献
260.
In the midst of rapidly proliferating engagement efforts around climate adaptation, attention to the design and evaluation of decision support processes and products is warranted. We report on the development and evaluation of a process framework called the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS) process. VCAPS is a systematic approach to integrate local knowledge with scientific understanding by providing opportunities for facilitated, deliberative learning-based activities with local decision makers about climate change vulnerability and adaptation. We introduce the conceptual basis of the process in analytic-deliberation, hazard management, and vulnerability. Our evaluations from eight coastal communities where the approach was applied point to four assets of VCAPS: it promotes synthesis of local and scientific knowledge; it stimulates systems thinking and learning; it facilitates governance by producing action plans with transparent justifications; and it accommodates participant time constraints and preferences. 相似文献