全文获取类型
收费全文 | 100篇 |
免费 | 0篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 1篇 |
环保管理 | 21篇 |
综合类 | 10篇 |
基础理论 | 28篇 |
污染及防治 | 23篇 |
评价与监测 | 7篇 |
社会与环境 | 5篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2019年 | 2篇 |
2017年 | 3篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 1篇 |
2009年 | 4篇 |
2008年 | 4篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有100条查询结果,搜索用时 15 毫秒
31.
Tony Svejcar Chad Boyd Kirk Davies Matthew Madsen Jon Bates Roger Sheley Clayton Marlow David Bohnert Mike Borman Ricardo Mata-Gonzàlez John Buckhouse Tamzen Stringham Barry Perryman Sherman Swanson Kenneth Tate Mel George George Ruyle Bruce Roundy Chris Call Kevin Jensen Karen Launchbaugh Amanda Gearhart Lance Vermeire John Tanaka Justin Derner Gary Frasier Kris Havstad 《Environmental management》2014,53(6):1035-1038
In a previous article, Beschta et al. (Environ Manag 51(2):474–491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and their publication is more of an opinion article. Their conclusions do not reflect the complexities associated with herbivore grazing. Because grazing is a complex ecological process, synthesis of the scientific literature can be a challenge. Legacy effects of uncontrolled grazing during the homestead era further complicate analysis of current grazing impacts. Interactions of climate change and grazing will depend on the specific situation. For example, increasing atmospheric CO2 and temperatures may increase accumulation of fine fuels (primarily grasses) and thus increase wildfire risk. Prescribed grazing by livestock is one of the few management tools available for reducing fine fuel accumulation. While there are certainly points on the landscape where herbivore impacts can be identified, there are also vast grazed areas where impacts are minimal. Broad scale reduction of domestic and wild herbivores to help native plant communities cope with climate change will be unnecessary because over the past 20–50 years land managers have actively sought to bring populations of native and domestic herbivores in balance with the potential of vegetation and soils. To cope with a changing climate, land managers will need access to all available vegetation management tools, including grazing. 相似文献
32.
Community Sustainability Plans to enable change towards sustainable practice – a Scottish case study
Joanneke Hélène Joséphine Kruijsen Alan Owen Donald Murray Gordon Boyd 《Local Environment》2013,18(7):748-766
There is a need for a global shift towards a low-carbon society and this requires action at the local level. The aim of the study into sustainable community development is to clarify the role of a community as a whole rather than the role of individuals within that community. Mixed methods of literature review and empirical study have been used to translate the knowledge and experience with urban sustainable development into empirical knowledge of a rural, market town setting. The exemplary case study is the Scottish market town Huntly. The main findings of the study show the need for three ingredients for a Community Sustainability Plan for a town such as Huntly. Community involvement is crucial in developing such plans in a rural setting. Further research in more remote settings, e.g. coastal and island communities, is needed to allow broader conclusions on rural sustainable development. 相似文献
33.
Trimethylphenylammonium-smectite as an effective adsorbent of water soluble aromatic hydrocarbons 总被引:1,自引:0,他引:1
Homoionic trimethylphenylammonium (TMPA)- and tetramethylammonium (TMA)-clays were prepared by ion-exchange reactions using two smectite clays that differed in their cation exchange capacities and surface charge densities. These clays are referred to as a low-charge (SAC) and high-charge (SWa)-smectite. The organo-clays were evaluated as adsorbents of water soluble aromatic hydrocarbons including benzene, toluene, ethylbenzene, p-xylene, butylbenzene, and naphthalene. All of the aromatic hydrocarbons tested were effectively removed from water by the low-charge TMPA-smectite. The low-charge TMA-smectite was an effective adsorbent for benzene but was ineffective in the removal of the alkylbenzenes and naphthalene from water. The effect of surface charge on the adsorption properties of TMPA-smectite was pronounced. The uptake of benzene and toluene by the high-charge TMPA-smectite was greatly reduced as compared to the low-charge TMPA-smectite. These results suggest the utility of TMPA-smectite as a liner material for petroleum storage containers and waste disposal reservoirs. The use of TMPA-smectite in conjunction with Na-smectite would provide a barrier with the ability to impede the flow of water and to effectively adsorb dissolved organic contaminants. 相似文献
34.
Emily Boyd Nate Hultman J. Timmons Roberts Esteve Corbera John Cole Alex Bozmoski Johannes Ebeling Robert Tippman Philip Mann Katrina Brown Diana M. Liverman 《Environmental Science & Policy》2009,12(7):820-831
The Clean Development Mechanism (CDM) has successfully demonstrated that market-based mechanisms can achieve some cost effective emissions reductions in developing countries. However the distribution of CDM projects has been extremely uneven across countries and regions, and a few technologies and sectors have dominated the early stages of CDM experience. This has caused some to question whether the CDM has fallen short of its potential in contributing to sustainable development. We review the broad patterns of CDM project approvals and evaluate 10 CDM projects according to their sustainability benefits. The difficulty of defining “sustainable development” and the process of defining criteria by individual non-Annex 1 governments has meant that sustainable development concerns have been marginalized in some countries. Given these observed limitations, we present possible CDM policy futures, focusing on the main proposals for a post-2012 climate regime. Five options for enhancing the sustainable development benefits in the CDM are discussed, including proactive approaches to favour eligibility of emission reduction projects which ensure such co-benefits. 相似文献
35.
The breeding performance of higher predators has often been used to monitor fluctuations in the abundance of important prey
stocks in marine ecosystems. The development of electronic data-loggers in recent years has also provided the opportunity
of using wide-ranging marine animals to measure physical oceanographic conditions. In this study, time–depth recorders (TDRs)
programmed to record temperature were deployed on female Antarctic fur seals (Arctocephalus gazella) at Bird Island, South Georgia (54°00′S; 38°02′W) during the breeding seasons 1994 to 1998. Temperature sensors had relatively
slow response times, and thermal radiation errors occurred during the day when seals spent a large proportion of their time
at the surface. Nevertheless, measurements provided temperature–depth profiles which were typical of the vertical stratification
of the ocean. During the early stages of a foraging trip temperature increased, suggesting that fur seals travelled northwards
from South Georgia towards the warmer waters of the Polar Front. In addition, higher temperatures were recorded by females
that remained at sea for longer, implying that these individuals also travelled further. Mean sea-surface temperature (SST)
increased from ∼1 to 4 °C from December to March and agreed with SSTs from ship, buoy and satellite. Future studies on marine
mammals which combine satellite tracking with oceanographic measurements are likely to provide valuable information on biophysical
aspects of the ocean.
Received: 16 June 1998 / Accepted: 13 February 1999 相似文献
36.
Rognvald Boyd Sarah-Jane Barnes Patrice De Caritat Victor A. Chekushin Victor A. Melezhik Clemens Reimann Michael L. Zientek 《Atmospheric environment (Oxford, England : 1994)》2009,43(7):1474-1480
Published estimates for base metal emissions from the copper–nickel industry on the Kola Peninsula are re-examined in the light of (a) chemical data on the composition of the ores; (b) official emission figures for 1994; and (c) modelled emissions based on dry and wet deposition estimates derived from data for snow and rain samples collected in 1994. The modelled emissions, official emission figures and chemical data are mutually compatible for Ni, Cu and Co and show that previously published figures underestimated the emissions of the major elements, Ni and Cu (though within the same order of magnitude) and overestimated the emissions of As, Pb, Sb and Zn by up to several orders of magnitude, in some cases exceeding the calculated total input to the plants. Published estimates have neglected information on the nature and chemistry of the ores processed in metallurgical industries in the Noril'sk area of Siberia and the Urals. Revised emission estimates for 1994, using knowledge of the chemistry of the ores, are proposed: taken with published information on total emissions up to 2000 these data give an indication of emission levels in more recent years. 相似文献
37.
The significance of metal hyperaccumulation for biotic interactions 总被引:13,自引:0,他引:13
Metal hyperaccumulating plants contain very high metal contents. Because of the general toxicity of metals, chemically-mediated
biotic interactions involving hyperaccumulating plants may differ greatly from those of non-hyperaccumulators. Recent research
has demonstrated a defensive function for hyperaccumulated metals against herbivores and pathogens. We predict that some herbivore/pathogen
species have evolved metal tolerance, and suggest that resulting high metal levels in herbivores/pathogens may defend them
against their own predators. Little is known regarding interference and commensal interactions involving hyperaccumulating
plants. Decreased competition may occur through an interference interaction similar to allelopathy, in which enrichment of
metal in the soil under a hyperaccumulator plant's canopy may inhibit another plant species, thus resulting in “elemental
allelopathy”. Metal enrichment of soil under hyperaccumulators also may result in commensalism if another plant species (possibly
another hyperaccumulator) derives a benefit from growing in the metal-enriched soil under the canopy of a hyperaccumulating
overstory plant. It seems likely that high-metal plant litter will host a specialized microflora of decomposers and may affect
nutrient cycling rates. Mutualist biotic interactions also may be affected by the elevated metal contents of hyperaccumulating
species. Mycorrhizal fungi may form mutualisms with hyperaccumulators, but the phenomenon is poorly-explored. The few cases
investigated to date have not detected mycorrhizae. Pollination and seed dispersal mechanisms may require biotic vectors that
might be affected by plant metal content. Hyperaccumulating plants may have solved this dilemma in three ways. First, some
may rely on abiotic vectors for pollen or seed dispersal. Second, biotic vectors used by these species may have varied diets
and thus dilute metal intake to non-toxic levels. Finally, biotic vectors may have evolved tolerance of elevated dietary levels
of metals, and perhaps have become specialists on hyperaccumulator species.
Received 7 November 1997; accepted 28 December 1997. 相似文献
38.
39.
A microcosm experiment was designed to evaluate the effects of the simulated deposition of uncontaminated dredged material
on nematode assemblages from estuarine intertidal mud. The main objective was to assess the ability of nematodes to migrate
vertically into native muddy and non-native sandy sediment deposited in different amounts and frequencies. Results from univariate
and graphical methods of data-evaluation revealed that nematodes were capable of migrating over a wide depth range from the
bottom mud layer into the top layer of deposited sand and mud. A diverse mud assemblage of nematodes was able to survive in
non-native fine sand for the experimental period of 2 mo. Multivariate analyses showed that the amount of deposit and the
frequency of deposition were interactive factors. A high amount of sediment deposited once at the beginning of the experiment
caused more severe changes in assemblage structure than the same amount deposited in more frequent but smaller doses. The
response of most species to the experimental treatments appeared to be an integrated response to the enhancing effect of food
input accompanying the deposit and the negative effect of burial. Upward migration of nematodes is a process which has often
been underestimated in its importance for recolonisation of areas where uncontaminated dredged material is deposited. Active
migration of nematodes can significantly affect the recovery of a dredgings disposal site.
Received: 29 July 1999 / Accepted: 17 January 2000 相似文献
40.
Ten placentae from pregnancies proceeding to term from mothers who on routine screening at 16–18 weeks gestation were found to have a raised serum AFP but no increase in amniotic fluid AFP and no fetal abnormality, were studied using morphometric techniques. The results were compared with 20 placentae from normal term pregnancies where the maternal serum AFP level was not elevated. The mean total placental volume, volume of parenchyma and villous surface area were increased in the placentae associated with a raised maternal serum AFP. More of these placentae were infarcted and the fetal-placental weight ratio was significantly lower. The hypothesis that elevation of maternal serum AFP level is related to the increase in placental size is addressed. 相似文献