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491.
492.
Importance of dispersal routes that minimize open‐ocean movement to the genetic structure of island populations 下载免费PDF全文
E. L. Harradine M. E. Andrew J. W. Thomas R. A. How L. H. Schmitt P. B. S. Spencer 《Conservation biology》2015,29(6):1704-1714
Islands present a unique scenario in conservation biology, offering refuge yet imposing limitations on insular populations. The Kimberley region of northwestern Australia has more than 2500 islands that have recently come into focus as substantial conservation resources. It is therefore of great interest for managers to understand the driving forces of genetic structure of species within these island archipelagos. We used the ubiquitous bar‐shouldered skink (Ctenotus inornatus) as a model species to represent the influence of landscape factors on genetic structure across the Kimberley islands. On 41 islands and 4 mainland locations in a remote area of Australia, we genotyped individuals across 18 nuclear (microsatellite) markers. Measures of genetic differentiation and diversity were used in two complementary analyses. We used circuit theory and Mantel tests to examine the influence of the landscape matrix on population connectivity and linear regression and model selection based on Akaike's information criterion to investigate landscape controls on genetic diversity. Genetic differentiation between islands was best predicted with circuit‐theory models that accounted for the large difference in resistance to dispersal between land and ocean. In contrast, straight‐line distances were unrelated to either resistance distances or genetic differentiation. Instead, connectivity was determined by island‐hopping routes that allow organisms to minimize the distance of difficult ocean passages. Island populations of C. inornatus retained varying degrees of genetic diversity (NA = 1.83 – 7.39), but it was greatest on islands closer to the mainland, in terms of resistance‐distance units. In contrast, genetic diversity was unrelated to island size. Our results highlight the potential for islands to contribute to both theoretical and applied conservation, provide strong evidence of the driving forces of population structure within undisturbed landscapes, and identify the islands most valuable for conservation based on their contributions to gene flow and genetic diversity. 相似文献
493.
Sidhu Jatinder P. S. Ahmed Warish Palmer Andrew Smith Kylie Hodgers Leonie Toze Simon 《Environmental science and pollution research international》2017,24(23):19001-19010
Environmental Science and Pollution Research - Large-scale wastewater schemes rely on multi-barrier approach for the production of safe and sustainable recycled water. In multi-barrier wastewater... 相似文献
494.
Andrew Macintosh 《Mitigation and Adaptation Strategies for Global Change》2013,18(7):1035-1055
Urban planning has the potential to be a powerful tool for facilitating efficient and equitable adaptation to climate change-related coastal hazards (‘coastal climate hazards’). However, if urban planning measures are poorly designed or implemented, it can increase costs and vulnerability, and unfairly affect the interests of particular groups. Through a case study on the coastal climate hazard planning framework in Victoria, Australia, this paper aims to illustrate how urban planning measures can lead to maladaptation and draw lessons for the future design and implementation of planning responses. Five main policy lessons are drawn from the case study. First, planning frameworks should encourage the adoption of robust approaches that are as insensitive to the uncertainties associated with coastal climate hazards as possible. Secondly, policy makers need to be mindful of the opportunity costs and equity implications of planning responses. Thirdly, to be sustainable, planning responses must be robust to social and political factors, something that can be achieved through the use of flexible approaches that allow continued use and development of land but on conditions that protect the interests of governments and communities. Fourthly, policy makers need to be mindful of transaction costs. Finally, when devolving planning responsibilities to lower levels of government, policy makers need to ensure that the objectives of planning frameworks are clear, there is minimal ambiguity in decision guidelines, and that the resourcing and capacity constraints of planning bodies are appropriately considered. 相似文献
495.
Alola Andrew Adewale Lasisi Taiwo Temitope Eluwole Kayode Kolawole Alola Uju Violet 《Environmental science and pollution research international》2021,28(2):1752-1761
Environmental Science and Pollution Research - Although the Organization for Economic Co-operation and Development (OECD) member countries are largely regarded as a high human development index and... 相似文献
496.
Twum Florence Appiah Long Xingle Salman Muhammad Mensah Claudia Nyarko Kankam William Adomako Tachie Andrew Kwamena 《Environmental science and pollution research international》2021,28(14):17119-17131
Environmental Science and Pollution Research - This study employs super-efficiency DEA model with desirable inputs and an undesirable output in calculating environmental efficiency values in... 相似文献
497.
M.S. Sankar Padmanava Dash Shatrughan Singh YueHan Lu Andrew E. Mercer Shuo Chen 《环境科学学报(英文版)》2019,31(3):130-147
The objective of this research was to quantify the temporal variation of dissolved organic matter(DOM) in five distinct waterbodies in watersheds with diverse types of land use and land cover in the presence and absence of sunlight. The water bodies were an agricultural pond, a lake in a forested watershed, a man-made reservoir, an estuary, and a bay. Two sets of samples were prepared by dispensing unfiltered samples into filtered samples in 1:10 ratio(V/V). The first set was exposed to sunlight(10 hr per day for 30 days) for examining the combined effect of photo-biodegradation, while the second set was stored in dark for examining biodegradation alone. Spectroscopic measurements in tandem with multivariate statistics were used to interpret DOM lability and composition. The results suggest that the agricultural pond behaved differently compared to other study locations during degradation experiments due to the presence of higher amount of microbial humic-like and protein-like components derived from microbial/anthropogenic sources. For all samples, a larger decrease in dissolved organic carbon(DOC) concentration(10.12% ±9.81% for photo-biodegradation and 6.65% ± 2.83% for biodegradation) and rapid transformation of DOM components(i.e., terrestrial humic-like components into microbial humic and protein-like components) were observed during photo-biodegradation experiments.Results suggest that sunlight facilitated DOM biodegradation, resulting in simpler recalcitrant molecules regardless of original composition. Overall, it was found that combined effects of light and bacteria are more efficient than bacterial effects alone in remineralizing and altering DOM, which highlights the crucial importance of sunlight in transforming aquatic DOM. 相似文献
498.
Elevated arsenic and selenium concentrations in water cause health problems to both humans and wildlife. Natural and anthropogenic activities have caused contamination of these elements in waters worldwide, making the development of efficient cost-effective methods in their removal essential. In this work, removal of arsenate and selenite from water by adsorption onto a natural goethite(α-FeO OH) sample was studied at varying conditions. The data was then compared with other arsenate, selenite/goethite adsorption systems as much of literature shows discrepancies due to varying adsorption conditions. Characterization of the goethite was completed using inductively coupled plasma mass spectrometry, X-ray diffraction, Fouriertransform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller surface area analysis. Pseudo-first order(PFO) and pseudo-second order(PSO) kinetic models were applied; including comparisons of different regression methods. Various adsorption isotherm models were applied to determine the best fitting model and to compare adsorption capacitates with other works. Desorption/leaching of arsenate and selenite was studied though the addition of phosphate and hydroxyl ions. Langmuir isotherm modeling resulted in maximum adsorption capacities of 6.204 and 7.740 mg/g for arsenate and selenite adsorption,respectively. The PSO model applied with a non-linear regression resulted in the best kinetic fits for both adsorption and desorption of arsenate and selenite. Adsorption decreased with increasing pH. Phosphate induced desorption resulted in the highest percentage of arsenate and selenite desorbed, while hydroxide induced resulted in the fastest desorption kinetics. 相似文献
499.
Jarvie HP Neal C Withers PJ Baker DB Richards RP Sharpley AN 《Journal of environmental quality》2011,40(2):492-504
Extended end-member mixing analysis (E-EMMA) is presented as a novel empirical method for exploring phosphorus (P) retention and release in rivers and watersheds, as an aid to water-quality management. E-EMMA offers a simple and versatile tool that relies solely on routinely measured P concentration and flow data. E-EMMA was applied to two river systems: the Thames (U.K.) and Sandusky River (U.S.), which drain similar watershed areas but have contrasting dominant P sources and hydrology. For both the Thames and Sandusky, P fluxes at the watershed outlets were strongly influenced by processes that retain and cycle P. However, patterns of P retention were markedly different for the two rivers, linked to differences in P sources and speciation, hydrology and land use. On an annual timescale, up to 48% of the P flux was retained for the Sandusky and up to 14% for the Thames. Under ecologically critical low-flow periods, up to 93% of the P flux was retained for the Sandusky and up to 42% for the Thames. In the main River Thames and the Sandusky River, in-stream processes under low flows were capable of regulating the delivery of P and modifying the timing of delivery in a way that may help to reduce ecological impacts to downstream river reaches, by reducing ambient P concentrations at times of greatest river eutrophication risk. The results also suggest that by moving toward cleaner rivers and improved ecosystem health, the efficiency of P retention may actually increase. 相似文献
500.
Detecting water quality improvements following watershed management changes is complicated by flow-dependent concentrations and nonlinear or threshold responses that are difficult to detect with traditional statistical techniques. In this study, we evaluated the long-term trends (1997-2009) in total P (TP) concentrations in the Illinois River of Oklahoma, and some of its major tributaries, using flow-adjusted TP concentrations and regression tree analysis to identify specific calendar dates in which change points in P trends may have occurred. Phosphorus concentrations at all locations were strongly correlated with stream flow. Flow-adjusted TP concentrations increased at all study locations in the late 1990s, but this trend was related to a change in monitoring practices where storm flow samples were specifically targeted after 1998. Flow-adjusted TP concentrations decreased in the two Illinois River sites after 2003. This change coincided with a significant decrease in effluent TP concentrations originating with one of the largest municipal wastewater treatment facilities in the basin. Conversely, flow-adjusted TP concentrations in one tributary increased, but this stream received treated effluent from a wastewater facility where effluent TP did not decrease significantly over the study period. Results of this study demonstrate how long-term trends in stream TP concentrations are difficult to quantify without consistent long-term monitoring strategies and how flow adjustment is likely mandatory for examining these trends. Furthermore, the study demonstrates how detecting changes in long-term water quality data sets requires statistical methods capable of identifying change point and nonlinear responses. 相似文献