全文获取类型
收费全文 | 286篇 |
免费 | 6篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 16篇 |
废物处理 | 7篇 |
环保管理 | 74篇 |
综合类 | 36篇 |
基础理论 | 76篇 |
环境理论 | 1篇 |
污染及防治 | 54篇 |
评价与监测 | 19篇 |
社会与环境 | 5篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 5篇 |
2022年 | 3篇 |
2021年 | 3篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 11篇 |
2015年 | 7篇 |
2014年 | 5篇 |
2013年 | 22篇 |
2012年 | 10篇 |
2011年 | 14篇 |
2010年 | 4篇 |
2009年 | 14篇 |
2008年 | 14篇 |
2007年 | 12篇 |
2006年 | 10篇 |
2005年 | 10篇 |
2004年 | 15篇 |
2003年 | 9篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 6篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 8篇 |
1989年 | 4篇 |
1987年 | 6篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1972年 | 3篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1961年 | 1篇 |
1959年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有293条查询结果,搜索用时 15 毫秒
271.
Laban Musinguzi Jackson Efitre Konstantine Odongkara Richard Ogutu-Ohwayo Fredrick Muyodi Vianny Natugonza Mark Olokotum Sharon Namboowa Shamim Naigaga 《Environment, Development and Sustainability》2016,18(4):1255-1273
Fisheries resources support livelihoods of fishing communities but are threatened by over-exploitation, habitat degradation, pollution, invasive species and climate change. Unlike the other threats, climate change has received limited consideration and reducing its risks requires appropriate adaptation strategies. This study used quantitative and qualitative methods to generate knowledge on fishers’ perceptions of climate change, changes in climate variables and their impacts on livelihoods, adaptation strategies, constraints to adaptation and required interventions to promote adaptation strategies that would enable fishers to build resilience to sustain their livelihoods. We found that fishers were aware of changes in climate conditions manifested by unpredictable seasons, floods and droughts. Fishing remained the main livelihood activity. However, the dominance of fishes had changed from Nile tilapia (Oreochromis niloticus L.) to the African catfish (Clarias gariepinus Burchell). Floods and droughts were associated with damage to gears, boats, landing sites and changes in fish catches and sizes, income from fishing and fish consumption. The fishers adapted by increasing time on fishing grounds and changing target species and fishing gear among other things. Some innovative fishers diversified to high-value crops and livestock. This increased their income beyond what was solely earned from fishing which provided an incentive for some of them to quit fishing. Livelihood diversification was enhanced by use of communications technology, membership of social groups, increasing fishing days and fishing experience. Adaptation was, however, constrained by limited credit, awareness and access to land, which require interventions such as improving access to credit, irrigation facilities, appropriate planting materials and awareness raising. We identified adaptation strategies, which if promoted and their constraints addressed, could increase resilience of fishers to the influence of climate change and sustain their livelihoods. 相似文献
272.
Kiley Daley Lisbeth Truelstrup Hansen Rob C. Jamieson Jenny L. Hayward Greg S. Piorkowski Wendy Krkosek Graham A. Gagnon Heather Castleden Kristen MacNeil Joanna Poltarowicz Emmalina Corriveau Amy Jackson Justine Lywood Yannan Huang 《Environmental science and pollution research international》2018,25(33):32926-32937
Drinking water in the vast Arctic Canadian territory of Nunavut is sourced from surface water lakes or rivers and transferred to man-made or natural reservoirs. The raw water is at a minimum treated by chlorination and distributed to customers either by trucks delivering to a water storage tank inside buildings or through a piped distribution system. The objective of this study was to characterize the chemical and microbial drinking water quality from source to tap in three hamlets (Coral Harbour, Pond Inlet and Pangnirtung—each has a population of <2000) on trucked service, and in Iqaluit (population ~6700), which uses a combination of trucked and piped water conveyance. Generally, the source and drinking water was of satisfactory microbial quality, containing Escherichia coli levels of <1 MPN/100 mL with a few exceptions, and selected pathogenic bacteria and parasites were below detection limits using quantitative polymerase chain reaction (qPCR) methods. Tap water in households receiving trucked water contained less than the recommended 0.2 mg/L of free chlorine, while piped drinking water in Iqaluit complied with Health Canada guidelines for residual chlorine (i.e. >0.2 mg/L free chlorine). Some buildings in the four communities contained manganese (Mn), copper (Cu), iron (Fe) and/or lead (Pb) concentrations above Health Canada guideline values for the aesthetic (Mn, Cu and Fe) and health (Pb) objectives. Corrosion of components of the drinking water distribution system (household storage tanks, premise plumbing) could be contributing to Pb, Cu and Fe levels, as the source water in three of the four communities had low alkalinity. The results point to the need for robust disinfection, which may include secondary disinfection or point-of-use disinfection, to prevent microbial risks in drinking water tanks in buildings and ultimately at the tap. 相似文献
273.
By committing to green procurement, the UK government has taken a key initial step towards sustainable development. But can this be put into practice? This policy analysis explores the background to green procurement in English local government through desk research and data collection, including interviews with five local authorities. It finds that green procurement has been encouraged through legislation, providing information and dismantling barriers, but momentum was lost following the Gershon review. Implementation of the new action plan would ensure green procurement becomes embedded within government procurement. New information to link up green procurement with organisational goals would also expand the horizons of green procurement. 相似文献
274.
The southeastern United States has experienced severe, recurrent drought, rapid human population growth, and increasing agricultural
irrigation during recent decades, resulting in greater demand for the water resources. During the same time period, freshwater
mussels (Unioniformes) in the region have experienced substantial population declines. Consequently, there is growing interest in determining how
mussel population declines are related to activities associated with water resource development. Determining the causes of
mussel population declines requires, in part, an understanding of the factors influencing mussel population dynamics. We developed
Pradel reverse-time, tag-recapture models to estimate survival, recruitment, and population growth rates for three federally
endangered mussel species in the Apalachicola–Chattahoochee–Flint River Basin, Georgia. The models were parameterized using
mussel tag-recapture data collected over five consecutive years from Sawhatchee Creek, located in southwestern Georgia. Model
estimates indicated that mussel survival was strongly and negatively related to high flows during the summer, whereas recruitment
was strongly and positively related to flows during the spring and summer. Using these models, we simulated mussel population
dynamics under historic (1940–1969) and current (1980–2008) flow regimes and under increasing levels of water use to evaluate
the relative effectiveness of alternative minimum flow regulations. The simulations indicated that the probability of simulated
mussel population extinction was at least 8 times greater under current hydrologic regimes. In addition, simulations of mussel
extinction under varying levels of water use indicated that the relative risk of extinction increased with increased water
use across a range of minimum flow regulations. The simulation results also indicated that our estimates of the effects of
water use on mussel extinction were influenced by the assumptions about the dynamics of the system, highlighting the need
for further study of mussel population dynamics. 相似文献
275.
Brian Miller Richard Reading Courtney Conway Jerome A. Jackson Michael Hutchins Noel Snyder Steve Forrest Jack Frazier Scott Derrickson 《Environmental management》1994,18(5):637-645
This paper discusses common organizational problems that cause inadequate planning and implementation processes of endangered
species recovery across biologically dissimilar species. If these problems occur, even proven biological conservation techniques
are jeopardized. We propose a solution that requires accountability in all phases of the restoration process and is based
on cooperative input among government agencies, nongovernmental conservation organizations, and the academic community. The
first step is formation of a task-oriented recovery team that integrates the best expertise into the planning process. This
interdisciplinary team should be composed of people whose skills directly address issues critical for recovery. Once goals
and procedures are established, the responsible agency (for example, in the United States, the US Fish and Wildlife Service)
could divest some or all of its obligation for implementing the plan, yet still maintain oversight by holding implementing
entities contractually accountable. Regular, periodic outside review and public documentation of the recovery team, lead agency,
and the accomplishments of implementing bodies would permit evaluation necessary to improve performance. Increased cooperation
among agency and nongovernmental organizations provided by this model promises a more efficient use of limited resources toward
the conservation of biodiversity. 相似文献
276.
Derek B. Booth David Hartley Rhett Jackson 《Journal of the American Water Resources Association》2002,38(3):835-845
ABSTRACT: For 20 years, King County, Washington, has implemented progressively more demanding structural and nonstructural strategies in an attempt to protect aquatic resources and declining salmon populations from the cumulative effects of urbanization. This history holds lessons for planners, engineers, and resource managers throughout other urbanizing regions. Detention ponds, even with increasingly restrictive designs, have still proven inadequate to prevent channel erosion. Costly structural retrofits of urbanized watersheds can mitigate certain problems, such as flooding or erosion, but cannot restore the predevelopment flow regime or habitat conditions. Widespread conversion of forest to pasture or grass in rural areas, generally unregulated by most jurisdictions, degrades aquatic systems even when watershed imperviousness remains low. Preservation of aquatic resources in developing areas will require integrated mitigation, which must including impervious‐surface limits, forest‐retention policies, stormwater detention, riparian‐buffer maintenance, and protection of wetlands and unstable slopes. New management goals are needed for those watersheds whose existing development precludes significant ecosystem recovery; the same goals cannot be achieved in both developed and undeveloped watersheds. 相似文献
277.
Amy M. Breman Jennifer C. Chow Lance U'Ren Elizabeth A. Normand Sadeem Qdaisat Li Zhao David M. Henke Rui Chen Chad A. Shaw Laird Jackson Yaping Yang Liesbeth Vossaert Rachel H. V. Needham Elizabeth J. Chang Daniel Campton Jeffrey L. Werbin Ron C. Seubert Ignatia B. Van den Veyver Jackie L. Stilwell Eric P. Kaldjian Arthur L. Beaudet 《黑龙江环境通报》2016,36(11):1009-1019
278.
Debra L. Bisson Danny R. Jackson Kenneth R. Williams Walter E. Grube 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1348-1354
WILT, ANS 16.1 and TCLP leach tests were performed on solidified/stabilized (s/s) wastes treated by Soliditech, Inc. of Houston, Texas as part of a U.S. EPA SITE demonstration project conducted in December 1988 at the Imperial Oil Company/ Champion Chemical Company Superfund site in Morganville, New Jersey. All three leaching tests performed on the s/s wastes indicated that the primary contaminants of concern (lead and PCBs) were not leachable. The ANS 16.1 static leach test for the s/s wastes provided diffusion coefficients (De) for Al, Ca, and Na that were comparable to those obtained from the WILT test. However, plots of the ANS 16.1 data indicated that wetting of the samples confounded the static leaching process. The large column WILT De was used to estimate that less than 0.8 μg/cm2 lead would leach from a one-cubic yard block of s/s waste in contact with groundwater over a 60-month leaching period. This corresponds to concentrations less than 10 μg/L lead in the water contacting the block of s/s waste. 相似文献
279.
280.
Yves Cherel Camille Fontaine George D. Jackson Christine H. Jackson Pierre Richard 《Marine Biology》2009,156(4):699-708
Stable isotopes are increasingly used in the study of trophic interactions of many aquatic animals and most recently cephalopods.
To evaluate the application of the method to squids, it is important to assess isotopic differences among and within consumer
tissues that may confound the resolution of ecological relationships. Inter- and intra-tissue isotopic variation was examined
in 55 individuals of the oceanic squid Todarodes filippovae that were collected at the beginning of April 2000 in the southwestern Indian Ocean (between 44°S, 76°E, and Saint Paul and
Amsterdam islands, 38°S, 78°E). Delipidated soft tissues (mantle, arm, buccal mass, gill and reproductive organs) showed small
δ13C and δ15N differences, which were probably tissue-specific. A lower carbon value was observed in the digestive gland as a consequence
of incomplete lipid removal. Hard tissues, such as beaks and gladii, had lower 15N values than soft tissues, which can be explained by the presence of chitin, a 15N-depleted molecule. Females (n = 38) and males (n = 17) had identical δ13C values, but females showed higher δ15N values than males. The difference was size-related rather than sex-related, however, as females were generally larger than
males. A comparison of similar-sized females and males produced identical nitrogen values. These data suggest dietary shifts
from lower to higher trophic levels during growth, because δ15N values of large T. filippovae were much higher than that of small specimens. As expected, nitrogen values of lower beaks and gladii of large squids increased
from the oldest to the most recently formed region, reflecting the progressive growth of chitinized tissues in parallel with
dietary changes. Sequential sampling along the growth increments of squid beaks and gladii can likely be used to produce a
chronological record of dietary information throughout an individual’s history. 相似文献