全文获取类型
收费全文 | 268篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 4篇 |
环保管理 | 68篇 |
综合类 | 32篇 |
基础理论 | 53篇 |
污染及防治 | 63篇 |
评价与监测 | 24篇 |
社会与环境 | 11篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 7篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 26篇 |
2012年 | 10篇 |
2011年 | 22篇 |
2010年 | 6篇 |
2009年 | 13篇 |
2008年 | 17篇 |
2007年 | 27篇 |
2006年 | 12篇 |
2005年 | 4篇 |
2004年 | 10篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 5篇 |
1993年 | 2篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1968年 | 2篇 |
1930年 | 1篇 |
排序方式: 共有273条查询结果,搜索用时 31 毫秒
101.
Linley Chiwona-Karltun Franklin Amuakwa-Mensah Caroline Wamala-Larsson Salome Amuakwa-Mensah Assem Abu Hatab Nolwandle Made Nathan Kanuma Taremwa Lemayon Melyoki Lettice Kinunda Rutashobya Thulisile Madonsela Marna Lourens Wendy Stone Alfred R. Bizoza 《Ambio》2021,50(4):794
Like the rest of the world, African countries are reeling from the health, economic and social effects of COVID-19. The continent’s governments have responded by imposing rigorous lockdowns to limit the spread of the virus. The various lockdown measures are undermining food security, because stay at home orders have among others, threatened food production for a continent that relies heavily on agriculture as the bedrock of the economy. This article draws on quantitative data collected by the GeoPoll, and, from these data, assesses the effect of concern about the local spread and economic impact of COVID-19 on food worries. Qualitative data comprising 12 countries south of the Sahara reveal that lockdowns have created anxiety over food security as a health, economic and human rights/well-being issue. By applying a probit model, we find that concern about the local spread of COVID-19 and economic impact of the virus increases the probability of food worries. Governments have responded with various efforts to support the neediest. By evaluating the various policies rolled out we advocate for a feminist economics approach that necessitates greater use of data analytics to predict the likely impacts of intended regulatory relief responses during the recovery process and post-COVID-19. 相似文献
102.
Lake Powell is a large reservoir in Utah and Arizona that has experienced large changes in water level during a recent drought. As a first step in assessing the connection between hydrologic and chemical changes at Lake Powell, we characterized the particle size and solid-phase bulk concentrations for 31 elements and 25 minerals in sediment from the inflow region and some shoreline locations by using laser diffractometry, X-ray fluorescence, elemental analysis, and X-ray diffraction Our results are consistent with previous results that show a negative correlation between particle size and concentrations of most elements and most minerals other than quartz and some feldspars. In our samples, however, solid-phase iron, rather than particle size or organic carbon, is the best predictor variable for the solid-phase concentrations of elements and minerals. Sediment characteristics vary on a scale of tens of kilometers, with fine sediment that is enriched in trace elementsnearer to the dam. These trends allow formulation of an algorithm for determining a water-level threshold below which sediment resuspension may alter water chemistry in a generic reservoir with a long and narrow sediment delta. 相似文献
103.
Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines 总被引:1,自引:0,他引:1
Zipper CE Burger JA Skousen JG Angel PN Barton CD Davis V Franklin JA 《Environmental management》2011,47(5):751-765
Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is
unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem
services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged
by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive
forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation
practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation
Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working
collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is
used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils
and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands’ capabilities
to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed
protection, and water quality protection to a greater extent than conventional reclamation practices. 相似文献
104.
Plant populations are regulated by a diverse array of herbivores that impose demographic filters throughout their life cycle. Few studies, however, simultaneously quantify the impacts of multiple herbivore guilds on the lifetime performance or population growth rate of plants. In African savannas, large ungulates (such as elephants) are widely regarded as important drivers of woody plant population dynamics, while the potential impacts of smaller, more cryptic herbivores (such as rodents) have largely been ignored. We combined a large-scale ungulate exclusion experiment with a five-year manipulation of rodent densities to quantify the impacts of three herbivore guilds (wild ungulates, domestic cattle, and rodents) on all life stages of a widespread savanna tree. We utilized demographic modeling to reveal the overall role of each guild in regulating tree population dynamics, and to elucidate the importance of different demographic hurdles in driving population growth under contrasting consumer communities. We found that wild ungulates dramatically reduced population growth, shifting the population trajectory from increase to decline, but that the mechanisms driving these effects were strongly mediated by rodents. The impact of wild ungulates on population growth was predominantly driven by their negative effect on tree reproduction when rodents were excluded, and on adult tree survival when rodents were present. By limiting seedling survival, rodents also reduced population growth; however, this effect was strongly dampened where wild ungulates were present. We suggest that these complex interactions between disparate consumer guilds can have important consequences for the population demography of long-lived species, and that the effects of a single consumer group are often likely to vary dramatically depending on the larger community in which interactions are embedded. 相似文献
105.
Sweden has led the way in Europe in environmental protection, ecologically based technological innovation and social democracy. As new economic and ethnographic realities impact upon it, it faces challenges to its policies and practices long familiar elsewhere in Europe. We report on a study for the Swedish Research Councils in which we examined the national framework and political strategy for sustainable development, and how the strategy is being implemented in Sweden's three major cities and two case-study municipalities. History and tradition, cultural homogeneity and a strong and shared sense between sectors of 'the public good', emerged as very important. Until recently, these have obviated the need for formal links between the environmental, social and economic agendas. They now appear inadequately developed at all levels of governance. Tensions in policy are being played out at the level of the municipality, to which power is highly devolved, and Local Agenda 21, interpreted as project rather than process, seems unequal to the task of integration. We suggest what lessons may be drawn from the Swedish experience if issues of power and trust, leadership and participatory vs representative democracy are to be resolved. 相似文献
106.
107.
Jennifer E. Dixon Neil J. Ericksen Janet L. Crawford Philip Berke 《Journal of Environmental Planning and Management》1997,40(5):603-614
The Resource Management Act 1991 provides a new mandate for effectsbased planning with its goal of sustainable management. Regional, city and district councils are responsible for administering the Act, including preparation of regional policy statements, regional and district plans. The paper reports on a collaborative research programme,funded by the New Zealand Foundation for Research, Science and Technology. The three-year programme has two objectives: (1) to determine the quality of policy statements and plans; and (2) to identify the extent and means by which councils co-ordinate policy statements and plans. Preliminary findings on implementation of the Act are presented. 相似文献
108.
The geographic distribution of the animals of Venezuela was analyzed as a basis for a series of guidelines to help develop strategies for their conservation. A total of 313 animal taxa is distributed among 24 geographic units, corresponding to the political divisions of the country. Three different criteria were considered in analyzing these data: (1) the number and density of threatened taxa were used to define a ranking system for geographic units; (2) "hotspots" were identified using the distribution of threatened endemics, and (3) a "critical faunas analysis" was used to determine the minimum number of geographic units needed to maximize the number of sampled taxa. The first two criteria emphasize the importance of protecting habitat in the northern portion of the country, where most human intervention has already taken place. But the southern portion of the country is where most of the undisturbed habitat remains. We suggest that the conservation of the animals of Venezuela must follow a mixed strategy, based on two principles: one, aimed mainly at threatened endemics, should focus on the protection of critical habitat north of the Orinoco river, the second, aimed at all threatened animals— particularly high-risk taxa—should focus on assuring the long-term persistence of the pristine habitat in the south. 相似文献
109.
110.
Janet K. Kern David A. Geier Françoise Ayzac James B. Adams Jyutika A. Mehta Mark R. Geier 《毒物与环境化学》2013,95(2):396-405
The purpose of this blinded study was to evaluate potential environmental toxicity in a cohort of neurotypical children (n = 28) living in a suburban area of north-central Texas in the United States (US) with a comparable age- and gender-matched cohort of neurotypical children (n = 28) living in a suburban area of southeastern France using urinary porphyrin testing: uroporphyrin (uP), heptacarboxyporphyrin (7cxP), hexacarboxyporphyrin (6cxP), pentacarboxyporphyrin (5cxP), precoproporphyrin (prcP), and coproporphyrin (cP). Results showed significantly elevated 6cxP, prcP (an atypical, mercury-specific porphyrin), and cP levels, and increasing trends in 5cxP levels, among neurotypical children in the USA compared to children in France. Data suggest that in US neurotypical children, there is a significantly increased body-burden of mercury (Hg) compared to the body-burden of Hg in the matched neurotypical children in France. The presence of lead contributing to the higher levels of cP also needs to be considered. Further, other factors including genetics can not be completely ruled out. 相似文献