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41.
Hurricanes devastated the Gulf coast of the USA in 2005. Hurricane Katrina, in particular, highlighted the compelling need to build more sustainable and hazard-resilient communities. Much can be learned from recovery efforts to rebuild the Gulf coast. Personal observations and interviews with planners, academics and others involved in recovery efforts inform this analysis, which focuses on New Orleans. A conceptual framework is developed and principles and operational imperatives outlined to guide action for building sustainable, hazard-resilient communities. Such communities will remain elusive unless ‘business as usual’ is confronted by a transformational process of developmental planning. Sustainable, hazard-resilient coastal communities are founded upon robust ‘critical infrastructure’ that is secured by planning and decision-making processes that enable coastal communities to build ‘layers of resilience’ to overcome ‘waves of adversity’. Planners need to take on a redefined role—as ‘new naval architects’—to design and build communities that are ‘sea-worthy’ in this age of coastal storms.
Bruce C. GlavovicEmail:
  相似文献   
42.
城市扩张速度的加快带来越来越多的农民丧失土地,从而引发的农民土地权益流失.这与我国“一切与农业为本,一切为农民着想”的扶农政策想违背,为解决这一问题,笔者从经济学角度探讨失地农民土地权益流失的原因,图1,参5.  相似文献   
43.
ABSTRACT

This article, through the use of political ecology perspectives on coercive conservation, aims to explain how in two separate Colombian Natural Parks and buffer zones, environmental policies designed to (re)take control of the frontier, have produced a similar territorial differentiation in the contention of illicit activities. Los Farallones in the Colombian Pacific and La Macarena/Puerto Rico in the Ariari region have experienced different stages of the armed conflict and are at the center of this analysis. I argue that in the contexts of both conflict escalation (1998–2007) and conflict de-escalation (2008–2016), the State in its attempt to control the frontier has not only had military intervention in areas of conservation but has also reinforced environmental programs that attack illegal mining and coca, producing both a territorially differentiated containment of illicit activities and an uneven progression of the illicit frontier.  相似文献   
44.
为研究人田泥沙对小开河灌区自然土壤的影响,用分析化验和工程测试等方法,分析了引黄泥沙和输沙人田后土壤颗粒组成、容重、孔隙状况等物理性状。结果表明:引黄泥沙中0.02~0.002mm的细粉粒比例最高,平均39-31%。小开河自然土壤中0.05-0.02mm的粗粉粒比例最高,为53.41%,泥沙中细粉粒和粘粒含量明显高于当地土壤。输沙人田使灌区土壤中0.02—0.002mm的细粉粒和〈0.002mm的粘粒比例明显增加,〉0.02mm的颗粒比例下降,虽有效避免了因渠首集中沉沙造成的土壤沙化和生态环境恶化,但增加了土壤的粘重程度。农田耕作在一定程度上增加土壤通气孔隙比例、降低土壤容重,但土壤毛管孔隙度依旧稳定在40%左右,毛管作用旺盛,使土壤通气状况不能满足作物需求。在黄河三角洲地区输沙入田的泥沙处理,应结合当地土壤的基本性质和水盐运动规律配置泥沙,以免增强当地土壤紧实、通透性差的性状。  相似文献   
45.
以兰州市西固区土地利用格局为例,利用2005年SPOT5遥感影像和正射航空影像数据,选取14个常用的景观指数,从景观水平和类型水平2个方面分析景观指数随尺度变化的基本规律,采用200m×200m正方形将研究区土地利用数据切分成规则格网,计算每个格网的多样性指数,通过半方差分析研究西固区多样性空间结构特征。结果表明:10m是西固区土地利用景观的本征观测尺度;研究区景观类型和景观格局特征随尺度增大变化显著,体现出一定的尺度依赖性;各乡(镇、街道)的景观指数呈现出城市中心—城乡交错带—乡村的分异特征,梯度变化明显;西固区多样性空间分布属于中等强度空间相关,高值区主要分布于黄河沿岸。  相似文献   
46.
为研究入田泥沙对小开河灌区自然土壤的影响,用分析化验和工程测试等方法,分析了引黄泥沙和输沙入田后土壤颗粒组成、容重、孔隙状况等物理性状。结果表明:引黄泥沙中0.02~0.002mm的细粉粒比例最高,平均39.31%。小开河自然土壤中0.05~0.02mm的粗粉粒比例最高,为53.41%,泥沙中细粉粒和粘粒含量明显高于当地土壤。输沙入田使灌区土壤中0.02~0.002mm的细粉粒和﹤0.002mm的粘粒比例明显增加,0.02mm的颗粒比例下降,虽有效避免了因渠首集中沉沙造成的土壤沙化和生态环境恶化,但增加了土壤的粘重程度。农田耕作在一定程度上增加土壤通气孔隙比例、降低土壤容重,但土壤毛管孔隙度依旧稳定在40%左右,毛管作用旺盛,使土壤通气状况不能满足作物需求。在黄河三角洲地区输沙入田的泥沙处理,应结合当地土壤的基本性质和水盐运动规律配置泥沙,以免增强当地土壤紧实、通透性差的性状。  相似文献   
47.
西安市生态文明建设评价及预测   总被引:2,自引:0,他引:2  
根据生态文明的涵义和生态市建设的总体思路,提出了生态文明建设3(系统层、子系统层、单项指标层)×3(经济发展,社会进步,环境保护)评价体系,其中包括25个单项指标。对西安市1998-2007年生态文明建设进行了定量评价研究,结果表明西安市生态文明建设处于整体上升的趋势;在此基础上,应用自回归预测模型对西安市经济、社会、环境和生态文明建设发展进行了预测,为西安市全面协调发展提供参考借鉴。  相似文献   
48.
为了更好地利用青岛崂山区地下空间资源,在全面分析该区地形、地质、水文等条件的基础上,结合岩土工程勘察原始数据和现场水样调查分析报告,根据模糊数学理论和专家经验,遴选出地形地貌、地质构造、工程地质、水文地质、洪水淹没、人口密集程度为评价因子并确定各因子的权重,研究构建了该区地下空间利用评价模型。将评价模型与GIS相结合,利用ArcGIS强大的空间分析功能,采用定量分析的方法得到地下空间利用适宜性分区。研究表明青岛崂山区地下空间建设适宜区面积为106.1km^2,占评价区域面积的73.8%;一般区域面积为26.5km^2,占评价区域面积的18.4%;不适宜区域面积为11.14km^2,占评价区域面积的7.8%。  相似文献   
49.
Late Quaternary extinctions and population fragmentations have severely disrupted animal‐plant interactions globally. Detection of disrupted interactions often relies on anachronistic plant characteristics, such as spines in the absence of large herbivores or large fruit without dispersers. However, obvious anachronisms are relatively uncommon, and it can be difficult to prove a direct link between the anachronism and a particular faunal taxon. Analysis of coprolites (fossil feces) provides a novel way of exposing lost interactions between animals (depositors) and consumed organisms. We analyzed ancient DNA to show that a coprolite from the South Island of New Zealand was deposited by the rare and threatened kakapo (Strigops habroptilus), a large, nocturnal, flightless parrot. When we analyzed the pollen and spore content of the coprolite, we found pollen from the cryptic root‐parasite Dactylanthus taylorii. The relatively high abundance (8.9% of total pollen and spores) of this zoophilous pollen type in the coprolite supports the hypothesis of a former direct feeding interaction between kakapo and D. taylorii. The ranges of both species have contracted substantially since human settlement, and their present distributions no longer overlap. Currently, the lesser short‐tailed bat (Mystacina tuberculata) is the only known native pollinator of D. taylorii, but our finding raises the possibility that birds, and other small fauna, could have once fed on and pollinated the plant. If confirmed, through experimental work and observations, this finding may inform conservation of the plant. For example, it may be possible to translocate D. taylorii to predator‐free offshore islands that lack bats but have thriving populations of endemic nectar‐feeding birds. The study of coprolites of rare or extinct taxonomic groups provides a unique way forward to expand existing knowledge of lost plant and animal interactions and to identify pollination and dispersal syndromes. This approach of linking paleobiology with neoecology offers significant untapped potential to help inform conservation and restoration plans. Un Eslabón Perdido entre un Loro No Volador y una Planta Parásita y el Papel Potencial de Coprolitos en Paleobiología de la Conservación  相似文献   
50.
Ken Burns' series on the national parks reveals the evolving values of the American nation, particularly in relation to nature. Through both the beauty and the history of these set apart spaces, Burns presents and to some extent critiques America's mythic dreams of nature. Nature as new world garden and as frontier shapes the story that is told. This essay focuses on two themes, science and pluralism, and argues the presentation of each (the former with less depth, the latter with more) is constrained by the mythic narrative of pristine America that seems unable to evolve, either in the face of ecological values of interrelationships or pluralistic values that re-shape understandings of democracy. More attention to the problematic of the notion of preservation of pristine America would have enabled the film to speak more powerfully not only of the history of the parks, but also of their future.  相似文献   
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