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771.
Manuel Larrán Jorge Jesús Herrera Madueño 《Journal of Environmental Planning and Management》2019,62(6):1019-1044
In the business context, many papers have examined whether certain variables can affect sustainability disclosure practices. However, research on universities has mainly been addressed to explore the extent of sustainability information reported with little focus on determining the factors that may affect it. This paper analyzes the influence exerted by some variables concerning the extent of information reported in the university sustainability reports included in this study. To accomplish this task, data were collected using a content analysis of the university sustainability reports extracted from the GRI sustainability disclosure database. The findings reveal that sustainability disclosure practices by universities are explained by different factors, among which are institutionalization, geographical region, external assurance and leadership. Such results are supported jointly by the underpinnings of the institutional and legitimacy theories in response to coercive and mimetic pressures and by the need to improve reputation in society. 相似文献
772.
Mar′?a Arrib′ere Mar′?a C Di′eguez Sergio Ribeiro Guevar Claudia P Queimali?nos Vesna Fajon Mariana Reissig Milena Horvat 《环境科学学报(英文版)》2010,22(8):1171-1178
The deep, ultraoligotrophic piedmont lakes of Northern Patagonia (Argentina) are located in pristine and barely impacted areas,
along a wide latitudinal range. Several studies have reported moderate to high total mercury (Hg) concentrations and contrasting
methylmercury (CH3Hg+) production in di erent lake compartments. Sources of Hg for western Patagonian terrestrial and aquatic
ecosystems are still not clear; while point sources can be ruled out and atmospheric deposition is a plausible source, along with
contribution from active volcanic areas of the Andes. In this investigation, we reported a noticeably seasonal, spatial (between lake
branches), and vertical (between water column strata) heterogeneity in the total Hg concentrations found in the pelagic zone of Lake
Moreno. Sterile water samples taken in a depth profile of the lake showed moderate to high concentrations of CH3Hg+ in autumn with
a decreasing trend with depth. Our results indicated that Hg is largely allocated in the plankton fraction between 10–53 m; which
dominated within the euphotic (epilimnetic) zone of the lake due to the high densities attained by two species of the dinoflagellate
Gymnodinium. The 53–200 m planktonic size fraction (comprising rotifers, ciliates and immature stages of crustaceans) and the > 200
m fraction (calanoid copepods and cladocerans) were found to bear strikingly lower total Hg concentrations, suggesting that the
magnification of Hg at the planktonic consumer level is negligible. 相似文献
773.
Rogelio Cruz-Martínez Adolfo Etchegaray Saulo Molina-Giraldo Belen Nieto-Castro Enrique Gil Guevara Joaquin Bustillos Miguel Martínez-Rodríguez Alma Gámez-Varela Daniel Saldivar-Rodríguez Erendira Chávez-González Rodolfo Keller Ricardo Russo Eduardo Yepez-García Fausto Coronel-Cruz Johnatan Torres-Torres Alejandro Rojas-Macedo Daniel Ibarra-Ríos Ricardo Ordorica-Flores Jaime Nieto-Zermeño Manuel Alcocer-Alcocer 《黑龙江环境通报》2019,39(7):519-526
774.
The influence of temperature (175 to 195°C), residence time (5 to 15 min), and sulfuric acid concentration in high (2 to 4% w/w) and low (0.5 to 1.5% w/w) levels in dilute acid pretreatment of Moringa oleifera Lam is studied. Glucose recoveries in the liquid fraction and in the hydrolyzed insoluble fraction as well as the presence of inhibitors in the liquid fraction are determined. Best experimental results are achieved at 185°C, 2% w/w acid concentration, and 5 min reaction time obtaining a glucose recovery of 83.68%. An increment in 48.81% in glucose yield compared with the one of not pretreated Moringa is obtained. 0.13 g ethanol/g Moringa from fermentation of pre-hydrolysate and hydrolysate obtained at the optimal pre-treatment conditions are obtained. 相似文献
775.
Julieta Soledad Borello Franca Giannini-Kurina Diego Alejandro Grassi Gonzalo Tentor Ana Irene Cañas Mirtha Maria Nassetta Edda Cristina Villaamil Lepori 《环境质量管理》2023,33(1):239-255
Veterinary drugs used in dairy production are potential contaminants of surface or groundwater sources, being able to affect human and environmental health. It is known that chronic exposure to antibiotics in low concentrations present in water can generate microbial resistance. This study aimed to evaluate the presence of veterinary drugs in 53 groundwater samples used for animal and human consumption, collected in dairy milking parlors, in an important milk-producing area of central Argentina, and to assess the risk to human health when they are used as drinking water. In 75% of the total samples analyzed, at least one veterinary drug was detected. The most frequently found drugs in water samples were the antibiotics tetracycline in 58.5% and oxytetracycline in 56.6%, and an anti-inflammatory, flunixin in 39.6%. In the water samples, the tetracycline and oxytetracycline concentrations were between 0.1 and 5.3 μg/L and flunixin concentrations were between 0.01 and 2.1 μg/L. The frequency of appearance and the concentration levels of the substances found in the water samples were evaluated according to the productivity, size, and production system (confined or pasture) of the dairy farms. Higher concentrations and proportions of water samples containing antibiotics were observed when the number of animals per dairy farm was >182 and when the productivity was high (>25 liters per animal per day). In the case of flunixin, the percentage of detection was similar in all evaluated categories. The risk assessment for children and adults, considering the intake of drinking water containing residues of these drugs, did not indicate a significant health risk. It would be advisable to evaluate other sources of drinking water, both surface and underground, in other regions of the country, to provide data to assess the impact of these substances and the other contaminants on environmental and human health. 相似文献
776.
Multimethod,multistate Bayesian hierarchical modeling approach for use in regional monitoring of wolves 下载免费PDF全文
José Jiménez Emilio J. García Luis Llaneza Vicente Palacios Luis Mariano González Francisco García‐Domínguez Jaime Múñoz‐Igualada José Vicente López‐Bao 《Conservation biology》2016,30(4):883-893
In many cases, the first step in large‐carnivore management is to obtain objective, reliable, and cost‐effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical‐site‐occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the naïve estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost‐effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well‐coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population‐parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters. 相似文献
777.
M.D. Bovea V. Ibáñez-Forés A. Gallardo F.J. Colomer-Mendoza 《Waste management (New York, N.Y.)》2010,30(11):2383-2395
The aim of this study is to compare, from an environmental point of view, different alternatives for the management of municipal solid waste generated in the town of Castellón de la Plana (Spain). This town currently produces 207 ton of waste per day and the waste management system employed today involves the collection of paper/cardboard, glass and light packaging from materials banks and of rest waste at street-side containers.The proposed alternative scenarios were based on a combination of the following elements: selective collection targets to be accomplished by the year 2015 as specified in the Spanish National Waste Plan (assuming they are reached to an extent of 50% and 100%), different collection models implemented nationally, and diverse treatments of both the separated biodegradable fraction and the rest waste to be disposed of on landfills.This resulted in 24 scenarios, whose environmental behaviour was studied by applying the life cycle assessment methodology. In accordance with the ISO 14040-44 (2006) standard, an inventory model was developed for the following stages of the waste management life cycle: pre-collection (bags and containers), collection, transport, pre-treatment (waste separation) and treatment/disposal (recycling, composting, biogasification + composting, landfill with/without energy recovery). Environmental indicators were obtained for different impact categories, which made it possible to identify the key variables in the waste management system and the scenario that offers the best environmental behaviour. Finally, a sensitivity analysis was used to test some of the assumptions made in the initial life cycle inventory model. 相似文献
778.
Polymorphism in soft coral larvae revealed by amplified fragment-length polymorphism (AFLP) markers 总被引:2,自引:0,他引:2
The dioecious Red Sea soft coral Parerythropodium fulvum fulvum breeds its nonsymbiotic planula larvae on the surface of female colonies for less than a week. After completing their development,
larvae crawl and settle near maternal colonies. Here we study the genetic polymorphism of developing larvae by the use of
amplified fragment-length polymorphism markers. Four reproductive colonies from shallow water populations (two from a dense
population and two from a less densely populated area 100 m away) were chosen, and ten larvae were randomly collected from
each colony. DNA was analyzed by using three different primer combinations producing 61, 63, 63 polymorphic markers, respectively.
All larvae exhibited different banding patterns from one another, illustrating the prominent role of sexual reproduction for
the production of larvae. Nei's mean genetic distances for all 12 possible pair-wise combinations for larval origins revealed,
in most cases, that sister larvae are genetically closer than larvae from different colonies and that larvae may be grouped
into three statistical clusters in accordance with colony origin and population studied. The usefulness of molecular methodologies
in coral population genetics is discussed.
Received: 26 March 1999 / Accepted: 19 October 1999 相似文献
779.
Pincheira Roxana Zúñiga Felipe Valencia Francisco 《Environmental science and pollution research international》2021,28(46):65573-65594
Environmental Science and Pollution Research - Planetary boundaries (PB) is a novel conceptual framework that assesses the state of processes fundamental to the stability of the Earth system.... 相似文献
780.
David W. Gibbons Chris Sandbrook William J. Sutherland Rezvin Akter Richard Bradbury Steven Broad Andy Clements Humphrey Q. P. Crick Joanna Elliott Ngawang Gyeltshen Melanie Heath Jonathan Hughes Richard K. B. Jenkins Alastair H. Jones Rocio Lopez de la Lama Nicholas B. W. Macfarlane Mike Maunder Ravikash Prasad Alfredo Romero-Muñoz Noa Steiner James Tremlett Rosie Trevelyan Savita Vijaykumar Irushinie Wedage Nancy Ockendon 《Conservation biology》2022,36(1):e13781
The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future. 相似文献