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961.
漫游峨眉山     
峨眉山位于成都西南约130km,主峰3099m,矗立在海拔不到500m的峨眉平原上。2600多米的高差造就了“一山有四季,十里不同天”的气候垂直分带。这使峨眉山有着非常丰富的动、植物资源,拥有3200多种植物,享有“植物王国”、“绿色宝库”的美称;拥有2300多种动物。这造成了峨眉山优美、秀丽的景色。峨眉山是中国佛教胜地的四大名山之一。孕育了悠久、灿烂的佛教文化。“蜀国多仙山,峨眉邈难四”。漫游雄、秀、幽、奇的峨眉山,足聆听一曲雄浑、优美的祖国颂歌。  相似文献   
962.
1IntroductionDuetotherapidglobalwarmingtrend,whichtookplaceinthe20thcentury,numerousunexpectedenvironmentalandecologicalisues...  相似文献   
963.
苏州苗家河水质污染对鱼类的影响   总被引:2,自引:0,他引:2  
通过对苏州古城区南园河水系苗家河水质和鱼类现状的调查,分析了水质对鱼类生长的影响。根据河道水质情况及渔业饵料基础,提出引进以摄食腐碎为主的鱼类等措施。  相似文献   
964.
介绍采用干湿结合法治理冲天炉烟尘及二氧化硫的工艺及治理效果,并对具体应用提出应该注意的问题  相似文献   
965.
We report a study which examined whether the decision of 135 couples to accept prenatal cystic fibrosis (CF) carrier screening would be influenced by the advent of gene therapy. A majority (91 couples; 67 per cent) felt that gene therapy for CF would not influence their decision to be screened. Twenty-two couples (16 per cent) stated that they would decline to be screened and an equal number felt ambivalent. Even if the life expectancy of a CF sufferer were increased by gene therapy to normal, 78 per cent of couples would still wish to avail themselves of prenatal carrier screening. A majority of women who decline screening do so because they are opposed to termination of pregnancy. The availability of gene therapy could increase the proportion of couples who accept screening.  相似文献   
966.
Abstract:  Invertebrates provide the majority of ecosystem services; thus, it is important that they be inventoried, monitored, and protected. Nevertheless, inventories, monitoring, and management generally focus on vertebrates and flowering plants. Consequently, there are few guidelines or case studies for invertebrates. We present a procedure for developing a monitoring program for species-rich invertebrates that entails (1) characterizing the community; (2) identifying surrogates for biodiversity; and (3) establishing efficient methods to monitor surrogates and any ecologically important or sensitive taxa. We used these procedures, biodiversity-based statistical advances, and a survey of arthropods to develop a monitoring plan for the forests of Shenandoah National Park, Virginia (U.S.A.). Our case study revealed that mixed hardwood and hemlock forests had significantly different compositions of arthropods in their soil and understory strata. Of the 10 orders tested Coleoptera and Hymenoptera were the only two to pass most of the five surrogate tests, and their combination improved predictions of overall arthropod diversity. Because arthropods represent the majority of macroscopic species in most ecosystems, the ability of this assemblage to predict overall arthropod diversity makes it a powerful surrogate. Of the 11 collecting methods used, the beat-sheet method was the most efficient for monitoring this surrogate assemblage. To complement this coarse-filter approach to monitoring at-risk, invasive, or other important taxa (fine filter), we used ordination analyses to match 66 taxa with the methods that most effectively sampled them. Our methods serve as a model for developing an invertebrate monitoring plan and should facilitate linking such monitoring with ecosystem functions and management.  相似文献   
967.
镇江市不断深化农业经营机制改革,大力发展产加销一条龙,贸工农一体化经营,把一家一户农民家庭小生产同国内外大市场有机联系起来,提高了农民的组织程度和专业化生产水平,协调了一二三产业间经济利益,建立了新的经济关系的优质,高产,高效,高创汇的市场产农业及新型组织管理体系,加快了农业生产社会化,产业化,市场化,现代化进程,使农业产业走向市场迈出了可喜的一步。  相似文献   
968.
ABSTRACT: A model for estimating seasonal fecal coliform concentrations in the Tchefuncte River as a function of river discharge was developed. Data on fecal coliform concentration were obtained from the Louisiana Department of Health and Hospitals and were available for a period of 15 years (1975 through 1992) from three locations. Stream flow data were obtained from a gaging station of the U. S. Geological Survey at Folsom, Louisiana. These data were available for 49 years (1943 through 1991). The climate of the area is characterized by different precipitation/runoff mechanisms for the summer and winter seasons. The division for seasons used in this analysis was May through October (summer season), and November through April (winter season). Because of the combined effects of climatic mechanisms causing precipitation and the seasonal variation of evapotranspiration, runoff is greater in the winter season resulting in higher fecal coliform counts in the Tchefuncte River. Statistical analysis revealed a statistically significant relationship between fecal coliform concentration and discharge for each season, at each of three sites on the Tchefuncte River.  相似文献   
969.
ABSTRACT: Major hydrometeorological factors pertinent to defining and understanding the hydrologic characteristics of urban and other small-basin storms were investigated using data from a continuous 44-year operation of a recording raingage network in Chicago. Factors included: the frequency distribution of basin mean rainfall and its relation to storm maximum precipitation; the spatial distribution characteristics of each storm, including storm rainfall reduction factors which are widely used in hydrologic design problems; and weather-related causes related to the frequency and intensity of severe rainstorms in the Chicago area in recent years. Results have indicated that urban mean rainfall frequencies were overestimated in earlier studies in which they were derived from point/areal mean rainfall ratios obtained from much shorter records on rural networks. Reduction factors were found to vary between urban and rural storm systems due to urban-related effects. Two factors were found to be potential contributors to the characteristics of severe rainstorm occurrences at Chicago. These include urban-induced rain enhancement and an upward climatic trend in the occurrence of heavy rainfall events during the sampling period. Study results should be generally applicable to other large urban areas in the Midwest and other regions of similar precipitation climate.  相似文献   
970.
李宏立 《灾害学》1996,11(3):89-92
针对灾区医疗队生存和救治工作中存在的问题,提出了解决办法,包括吃、住、行及救治等方面。  相似文献   
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