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461.
利用辽宁省1971年以来近40a气候资料和1981年以来25a物候期观测资料,采用数理统计、气候倾向率、地理信息系统精细化模拟等方法,对辽宁地区气候变化对主要农作物及自然物候的影响进行了分析,结果表明:近40a来辽宁地区增温趋势明显,气候变暖显著,2001-2006年全省平均大于10℃积温比20世纪70年代增加277.4℃,无霜期延长13d。农作物与自然物候对气候变暖反应敏感,种植带北移,近36a(1971-2006年)玉米适宜播期提前4d左右,水稻适宜生长期延长近8d;近25a(1981-2005年)草本植物春季展叶期每10a提前2~4d,草本、木本植物秋季枯黄期每10a推后5~7d。干旱、暴雨、暴雪等极端气象灾害频发,危害程度加重。气候变化对农业影响利弊并存。  相似文献   
462.
赤峰的第四纪冰川遗迹分布广泛,数量众多,而以冰臼群最为壮观,堪称"世界之最",开辟了中国花岗岩冰臼研究的新时代,增加了新的旅游类型,现已成为地质科学研究考察的科考旅游胜地,本文在评述赤峰冰臼资源的挖掘、保护与开发现状基础上、提出了赤峰冰臼资源在旅游开发中的功能定位与发展方向,并与其它内外景区间的协同开发等系列建议措施。  相似文献   
463.
ABSTRACT: An established trend analysis methodology was applied to the problem of identifying and quantifying stream base flow impacts from water withdrawals and water loss through interbasin transfers. Impacts were simulated using base flow values selected from two U.S. Geological Survey (USGS) continuous record streamflow sites located within the Pinelands of southern New Jersey. Study site base flows were regressed against index site base flows with monotonic and step trend tests applied to the residuals from the regression model. The smallest, significantly detectable (α= 0.10) percentage reduction within a given simulation was used as an estimate of the sensitivity of a trend test. Evaluation of the trend analysis methodology led to the following practical considerations regarding trend test sensitivity. The proportion of study site base flow variability explained by index site base flows should be maximized, while at the same time minimizing positive, first-order autocorrelation in the regression residuals. Given the importance of detecting autocorrelation, missing values should be avoided or minimized. The quarterly (three-month) interval reduced the magnitude of autocorrelation relative to a shorter two-month sampling interval. Sensitivity appeared to improve when equalizing the number of values before and after a base flow impact(s) while seasonally biased sampling appeared to reduce sensitivity. Based primarily on past trend detection studies, nonparametric tests were deemed a better choice over their parametric counterparts, due to the lack of stringent data distributional requirements coupled with little or no loss of power even when applied to normally distributed data.  相似文献   
464.
The most important question raised from issues of environmental degradation is how economic activities bring about changes that will result in pollution. In the pursuit of tourism economy, contrary to popular interest, the travel and tourism (T&T) industry may cause environmental damages through the emissions of carbon dioxide (CO2) from energy consumption in areas such as transportation and delivery of amenities. Given this major concern, this paper attempts to investigate the linkage between tourism and CO2 emissions in Malaysia between 1981 and 2011. In particular, this study fills the knowledge gap by taking a closer look at the impact of international tourist arrivals on CO2 emissions by sector – electricity and heat generation and transport. Results from the bound test method suggest that there exists a long-run relationship among the variables under consideration when CO2 emissions become the dependent variable. The original result is similarly robust to alternatives, which are CO2 emissions from sectors of electricity and heat generation and transport. Furthermore, the vector error correction model causality analysis indicates a causal relationship between tourism and CO2 emissions by transport and electricity and heat generation. Subsequently, several tourism-related policies are drawn from these findings.  相似文献   
465.
Recent studies have yielded definitive information about the nation's economic impacts from extreme climates, although some sectoral values rely on educated estimates since hard data does not exist. Review of existing measures of the national impacts from weather—climate conditions reveals annual average losses of $36 billion from extremes and gains averaging $26 billion when conditions are favorable (good growing seasons, mild winters, etc.). Comparison of these values with various measures of the national economy reveals that the impacts are relatively small, typically about 1% of the Gross Domestic Product and less than 2% of the federal budget. The current impact information provides a basis for assessing various estimates of the nation's financial impacts resulting from a future climate change due to global warming. Most such estimates predict values similar to the magnitude of current climate impacts. Moreover, most economists attempting such estimates express a large degree of uncertainty about their projections.  相似文献   
466.
This contribution presents the multi-objective synthesis of a company's supply network by integrating renewables (biomass and other waste, and solar energy) and accounting for several environmental footprints. The synthesis is based on a Mixed-Integer Linear Programming (MILP) problem. A previously developed model by the authors for achieving energy self-sufficiency by integrating renewables into companies’ supply networks has been extended for the evaluation of environmental impacts, such as energy, carbon, nitrogen, and water footprints. The achievement of an energy self-sufficient supply network has been considered whilst significantly reducing environmental impacts.The presented model is applied to multinational poultry-meat producing company. Direct (burdening) and indirect (unburdening) effects that form total effects on the environment are considered for the evaluation of environmental footprints. The results showed significant unburdening of the environment in terms of carbon and nitrogen footprints but, however, higher burdening in terms of the water footprint.  相似文献   
467.
Mussoorie, a hill resort in the Garhwal Himalaya reveals the changing trends and impacts of tourist activity on its environment. This study was carried out during 1993–1994 and it showed that while Mussoorie had a permanent residential population of 25400 during the winter months, in the peak tourist season of May and June the population exceeded 200000 per month. Because of this huge influx of tourists the demand for lodges/hotels and other related infra-structure and super-structure facilities and amenities in the area was enormous, and it imposed a great stress on the natural environment.The data collected showed that from 1958 to 1988 the number of tourists had increased gradually but that from 1989 tourism in the town escalated following the political disturbances in the Kashmir Valley. The main purpose of the tourism was recreation (80%). It was recorded that the greatest number (60%) of the tourists were middle aged, 53% of the tourists worked in professional services. The majority of the tourists preferred to use the indigenous hotels and about 96% of the tourists used a private vehicle rather than public transport.The installation of modern tourist related facilities and infra-structure has led to the aesthetic degradation of the landscape. Tourist facility development is often disorderly and scattered. To reduce the traffic to Mussoorie town it is suggested that some nearby places like Dhanolti and Park estate should be developed for tourism.  相似文献   
468.
This paper examines the role played by winds as a weather hazard in urban centres of southern Nigeria. It is observed that strong winds associated with rainstorms at the beginning of the rainy season are a threat to urban centres as they directly affect buildings and infrastructure. Wind hazards also have indirect social and economic consequences on the communities affected. Much of the damage done to buildings is as a result of inappropriate building designs that have not taken into consideration the wind environment. An inventory of reports of damage caused by winds during the first half of 1995 showed that different towns in eight states were affected. These incidences occurred mainly at the beginning of the rainy season when strong winds are associated with linesqualls. Although wind related hazards have not been adequately acknowledged as an environmental problem that needs to be properly addressed in Nigeria, as in the case of flooding, results have shown that it is a problem that requires government intervention in view of global climate change and consequent extreme weather events. Wind hazard awareness and preparedness as integral aspects of development policy and planning of the environment is therefore needed in West African countries where linesqualls are very significant rain producers.  相似文献   
469.
Atmospheric Change and Biodiversity in the Arctic   总被引:2,自引:0,他引:2  
The Canadian Arctic is characterized by a high variation in landform types and there are complex interactions between land, water and the atmosphere which dramatically affect the distribution of biota. Biodiversity depends upon the intensity, predictability and scale of these interactions. Observations, as well as predictions of large-scale climate models which include ocean circulation, reveal an anomalous cooling of northeastern Canada in recent decades, in contrast to the overall significant increase in average annual temperature in the Northern Hemisphere. Predictions from models are necessary to forecast the change in the treeline in the 21st century which may lead to a major loss of tundra. The rate of change in vegetation in response to climate change is poorly understood. The treeline in central Canada, for example, is showing infilling with trees, and in some locations, northerly movement of the boundary. The presence of sea ice in Hudson Bay and other coastal areas is a major factor affecting interactions between the marine and terrestrial ecosystems. Loss of ice and therefore hunting of seals by polar bears will reduce bear and arctic fox populations within the region. In turn, this is likely to have significant effects on their herbivorous prey populations and forage plants. Further, the undersurface of sea ice is a major site for the growth of algae and marine invertebrates which in turn act as food for the marine food web. A rise in sea-level may flood coastal saltmarsh communities leading to changes in plant assemblages and a decline in foraging by geese and other consumers. The anomalous cooling in the eastern Arctic, primarily in late winter and early spring, has interrupted northern migration of breeding populations of geese and ducks and led to increased damage to vegetation in southern arctic saltmarshes as a result of foraging. It is likely that there has been a significant loss of invertebrates in those areas where the vegetation has been destroyed. Warming will have major effects on permafrost distribution and on ground-ice resulting in a major destabilization of slopes and slumping of soil, and disruption of tundra plant communities. Disruption of peat and moss surfaces lead to loss of insulation, an increase in active-layer depth and changes in drainage and plant assemblages. Increases of UV-B radiation will strongly affect vulnerable populations of both plants and animals. The indigenous peoples will face major changes in life style, edibility of food and health standards, if there is a significant warming trend. The great need is for information which is sensitive to the changes and will assist in developing an understanding of the complex interactions of the arctic biota, human populations and the physical environment.  相似文献   
470.
Waste prevention has been addressed in the literature in terms of the social and behavioural aspects, but very little quantitative assessment exists of the environmental benefits. Our study evaluates the environmental consequences of waste prevention on waste management systems and on the wider society, using life-cycle thinking. The partial prevention of unsolicited mail, beverage packaging and food waste is tested for a "High-tech" waste management system relying on high energy and material recovery and for a "Low-tech" waste management system with less recycling and relying on landfilling. Prevention of 13% of the waste mass entering the waste management system generates a reduction of loads and savings in the waste management system for the different impacts categories; 45% net reduction for nutrient enrichment and 12% reduction for global warming potential. When expanding our system and including avoided production incurred by the prevention measures, large savings are observed (15-fold improvement for nutrient enrichment and 2-fold for global warming potential). Prevention of food waste has the highest environmental impact saving. Prevention generates relatively higher overall relative benefit for "Low-tech" systems depending on landfilling. The paper provides clear evidence of the environmental benefits of waste prevention and has specific relevance in climate change mitigation.  相似文献   
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