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61.
以中山市为例,在土地利用类型遥感解译数据的基础上,以系统网格采样法计算研究区内土地利用强度,并探索了土地利用强度的空间分布特征,以及受人类活动的驱动作用。研究结果表明:1 200 m能够很好地反映土地利用强度异质性在空间上的特征。研究区内的土地利用强度空间分布表现出较强的正相关性,2000—2010年,中山市土地利用强度分布模式由多点式向极化转变,而且还表现出核心区域的扩散效应。在整体的范围上看,土地利用强度的空间变异受尺度影响,随着尺度的增加各向同性的减弱,转变成明显的各向异性。研究区内自然条件以及区域发展政策的差异,导致研究区内行政单元间的土地利用强度空间分异明显。在人类活动影响的驱动下,研究区内土地利用强度异质性呈现增强的趋势。 相似文献
62.
选取废水、挥发酚、氰化物、COD、石油类和氨氮为中国工业水污染指标,利用分解分析方法将2004—2010年间的污染变化分解为规模效应、结构效应、污染治理效应、清洁技术效应和广义技术效应。结果显示,这5类效应的平均作用强度分别为2.08%、3.04%、15.61%、17.37%和32.88%,其中规模效应和广义技术效应是影响工业水污染的主导效应。各类效应对不同污染物的作用方向并不完全一致,规模效应促进污染物排放量的增加;结构效应以加重污染为主,污染治理效应和清洁技术效应以减轻污染为主;广义技术效应的平均作用强度和负向作用概率均最大,是现阶段中国工业水污染控制最为有效的手段。 相似文献
63.
Traditional agriculture benefits a rich diversity of plants and animals. The winter-flooded rice fields in the Qinling Mountains, China, are the last refuge for the endangered Asian crested ibis (Nipponia nippon), and intensive efforts have been made to protect this anthropogenic habitat. Analyses of multi-temporal satellite data indicate that winter-flooded rice fields have been continuously reduced across the current range of crested ibis during the past two decades. The rate of loss of these fields in the core-protected areas has unexpectedly increased to a higher level than that in non-protected areas in the past decade. The best fit (R2 = 0.87) numerical response model of the crested ibis population shows that a reduction of winter-flooded rice fields decreases population growth and predicts that the population growth will be constrained by the decline of traditional winter-flooded rice fields in the coming decades. Our findings suggest that the decline of traditional rice farming is likely to continue to pose a threat to the long-term survival and recovery of the crested ibis population in China.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0649-5) contains supplementary material, which is available to authorized users. 相似文献64.
土地资源的多级网格数据结构建立与应用研究 总被引:1,自引:0,他引:1
传统的基于行政区的土地统计数据不能完全表现区域内部土地利用的空间分异特征,以武汉市为实验区,对基于网格的统计信息算法STING(Statistical Information Grid-based method)进行扩展,以景观多样性指数为定量化指标对实验区进行四叉树划分生成不均匀多级网格,建立一种拟合了行政区划界线的不均匀的多级网格结构来存储、管理和分析土地数据。并以此多级网格数据结构为平台计算和生成实验区人口密度空间分异渲染图,初步抽取了人口分布与土地利用之间的关系。实验表明,基于多级网格的统计方法能更好地表达土地利用及其相关数据的空间分异性,利于对土地资源数据的进一步挖掘以抽取所需知识。 相似文献
65.
刘思佳 《环境工程技术学报》2022,12(6):1938-1946
为探索在新产业布局及发展形势下的产业园区外存量工业用地环境准入分类管控模式,采用空间叠图分析和承载力评估方法,基于“三线一单”分区管控要求对上海市产业园区外存量工业用地的空间布局约束、资源环境承载和环境风险防控进行评估。综合评估结果、新法规要求和规划方向的指引,梳理典型区环境准入管理的试点经验,提出以下建议:生态环境及产业、规划相关部门对产业园区外存量工业用地的现状及规划实施动态排摸;结合各地块资源环境特征、规划发展意向等因素,对不同规划导向的地块实施差异化分类管控;针对近中期保留的产业园区外存量工业用地,通过开展区域环评强化环境准入。
相似文献66.
本文选取二连油田蒙古林作业区生态环境质量为研究对象,对该区域内的土地利用/覆盖状况、植被状况、景观类型及其破碎度进行定性、定量研究。结果表明:(1)2008年,该区域土地利用类型主要为有林地、中覆盖度草地、低覆盖度草地、工矿交通建设用地和盐碱地等;工交建设占地明显。(2)该区2008年主要植物群落类型有:克氏针茅+羊草+杂类草、克氏针茅+锦鸡儿+杂类草、羊草+针茅+杂类草等;受到气候变暖等原因影响,小针茅已经在本区广泛分布。(3)该区2008年主要景观类型为针茅+锦鸡儿草原景观、针茅草原景观、羊草草原景观、林地景观、人工建设区景观和道路景观;景观破碎度较高,人为干扰较为严重。建议相关单位足够重视并采取切实可行的措施,防止本区生态环境恶化。 相似文献
67.
Mark C. Stone Rollin H. Hotchkiss Carter M. Hubbard Thomas A. Fontaine Linda O. Mearns Jeff G. Arnold 《Journal of the American Water Resources Association》2001,37(5):1119-1129
ABSTRACT: Water from the Missouri River Basin is used for multiple purposes. The climatic change of doubling the atmospheric carbon dioxide may produce dramatic water yield changes across the basin. Estimated changes in basin water yield from doubled CO2 climate were simulated using a Regional Climate Model (RegCM) and a physically based rainfall‐runoff model. RegCM output from a five‐year, equilibrium climate simulation at twice present CO2 levels was compared to a similar present‐day climate run to extract monthly changes in meteorologic variables needed by the hydrologic model. These changes, simulated on a 50‐km grid, were matched at a commensurate scale to the 310 subbasin in the rainfall‐runoff model climate change impact analysis. The Soil and Water Assessment Tool (SWAT) rainfall‐runoff model was used in this study. The climate changes were applied to the 1965 to 1989 historic period. Overall water yield at the mouth of the Basin decreased by 10 to 20 percent during spring and summer months, but increased during fall and winter. Yields generally decreased in the southern portions of the basin but increased in the northern reaches. Northern subbasin yields increased up to 80 percent: equivalent to 1.3 cm of runoff on an annual basis. 相似文献
68.
Zhenxu Tang Bernie A. Engel Kyoung J. Lim Brayn C. Pijanowski Jon Harbor 《Journal of the American Water Resources Association》2005,41(6):1347-1359
Increasing concern about the problems caused by urban sprawl has encouraged development and implementation of smart growth approaches to land use management. One of the goals of smart growth is water resources protection, in particular minimizing the runoff impact of urbanization. To investigate the magnitude of the potential benefits of land use planning for water resources protection, possible runoff impacts of historical and projected urbanization were estimated for two watersheds in Indiana and Michigan using a long term hydrological impact analysis model. An optimization component allowed selection of land use change placements that minimize runoff increase. Optimizing land use change placement would have reduced runoff increase by as much as 4.9 percent from 1973 to 1997 in the Indiana study watershed. For nonsprawl and sprawl scenarios in the Michigan watershed for 1978 to 2040, optimizing land use change placement would have reduced runoff increase by 12.3 percent and 20.5 percent, respectively. The work presented here illustrates both an approach to assessing the magnitude of the impact of smart growth and the significant potential scale of smart growth in moderating runoff changes that result from urbanization. The results of this study have significant implications for urban planning. 相似文献
69.
Glenn A. Hodgkins Robert W. Dudley Thomas G. Huntington 《Journal of the American Water Resources Association》2005,41(2):403-411
ABSTRACT: High springtime river flows came earlier by one to two weeks in large parts of northern New England during the 20th Century. In this study it was hypothesized that late spring/early summer recessional flows and late summer/early fall low flows could also be occurring earlier. This could result in a longer period of low flow recession and a decrease in the magnitude of low flows. To test this hypothesis, variations over time in the magnitude and timing of low flows were analyzed. To help understand the relation between low flows and climatic variables in New England, low flows were correlated with air temperatures and precipitation. Analysis of data from 23 rural, unregulated rivers across New England indicated little evidence of consistent changes in the timing or magnitude of late summer/early fall low flows during the 20th Century. The interannual variability in the timing and magnitude of the low flows in northern New England was explained much more by the interannual variability in precipitation than by the interannual variability of air temperatures. The highest correlation between the magnitude of the low flows and air temperatures was with May through November temperatures (r =?0.37, p= 0.0017), while the highest correlation with precipitation was with July through August precipitation (r = 0.67, p > 0.0001). 相似文献
70.