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701.
David J. C. Gill John E. Fa J. Marcus Rowcliffe Noëlle F. Kümpel 《Conservation biology》2012,26(6):1052-1060
Economic development in Africa is expected to increase levels of bushmeat hunting through rising demand for meat and improved transport infrastructure. However, few studies have tracked long‐term changes in hunter behavior as a means of testing this prediction. We evaluated changes in hunter behavior in a rural community in Equatorial Guinea over a period of rapid national economic growth, during which time road access to the regional capital greatly improved. We conducted offtake surveys (Supporting Information) over 3 7‐week periods at the same time of year in 1998, 2003, and 2010 and conducted hunter and household interviews (Supporting Information) in 2003 and 2010. We tested whether relations existed among catch, hunting effort, hunting strategy, and income earned through hunting and other livelihoods in 2003 and 2010. Although village offtake increased from 1775 kg in 1998 to 4172 kg in 2003, it decreased in 2010 to 1361 kg. Aggregate catch per unit effort (i.e., number of carcasses caught per hunter and per trap) decreased from 2003 to 2010, and the majority of hunters reported a decrease in abundance of local fauna. Although these results are indicative of unsustainable hunting, cumulative changes in offtake and catch per unit effort were driven by a contraction in the total area hunted following an out‐migration of 29 of the village's hunters, most of whom left to gain employment in the construction industry, after 2003. Hunters operating in both 2003 and 2010 hunted closer to the village because an increased abundance of elephants posed a danger and because they desired to earn income through other activities. Our study provides an example of national economic development contributing to a reduction in the intensity and extent of hunting. Factores de Cambio en la Captura de Cazadores y Estrategias de Caza en Sendje, Guinea Ecuatorial 相似文献
702.
703.
新毒性试验生物萼花臂尾轮虫的特性试验 总被引:2,自引:0,他引:2
研究了萼花臂尾轮虫Brachionus calyciflorus 24h标准化急性毒性试验的可行性和优越性。应用轮虫休眠卵,在25℃、3000lx的强光照下进行孵化,吸取孵化后3h内的幼体,进行24h(暗相)急性毒性试验。研究表明,Cu、Hg、NaPCP、SDS、Cd、Zn、Ni、NH3对B.calyciflorus的24h LC50值分别为0.022、0.043、1.30、1.47、1.77、1 相似文献
704.
Sophia Winkler-Schor Carena J. van Riper Adam Landon Rose Keller 《Conservation biology》2020,34(6):1404-1415
Values are the fundamental reasons why people engage in conservation behaviors. Recent research has called for a more refined approach to studying values in a way that accounts for the concept of eudaimonia. However, the empirical properties for a eudaimonic value scale have not been tested given that previous investigations have remained at the theoretical level. Drawing from an on-site survey of visitors to Denali National Park and Preserve, Alaska, we used a latent profile analysis to better understand the expression of multiple values of nature. Specifically, we segmented respondents by their value orientations with a particular focus on evaluating eudaimonic and hedonic values, alongside the established dimensions of altruistic, biospheric, and egoistic values. We identified 4 distinct subgroups defined by value orientations and validated these subgroups based on measures of conservation behavior and sociodemographic characteristics (e.g., age). These results indicated campaign messaging should harness a combination of eudaimonic, biospheric, and altruistic values to propel individual behavior. We also observed that hedonic and egoistic values defined how people related to nature and played a role, albeit less pronounced, in motivating them to take action. Our study is one of the first efforts to operationalize eudaimonia in a conservation context; thus, we have opened a new avenue for protected-area managers to align their strategies with the underlying values of stakeholders. 相似文献
705.
A. Deluca Luca R. Wagener C. Bough L. H. Melges De Figueiredo R. Carreira K. Wagener 《Chemistry and Ecology》2013,29(1-4):19-39
A survey was made in an area of 28 km2 around the outlest of Ipanema's submarine outfall in order to evaluate the impact of the raw domestic sewage effluent on coastal waters. Nutrient concentrations, dissolved oxygen, particulate matter and other physico-chemical parameters were measured monthly for 15 months. Copper and lead concentrations were also determined for two of the samplings. The outfall has been in operation for 18 years, and the parameters measured within the observation area appear to be in steady state. From the observed radial concentration gradients within the survey area, a real extension of the steady state distribution of particulate matter and of sewage-derived nitrogen was estimated. the stationary cloud of particulate organic matter was about 150 km2. From its total inventory and the discharge rate, a mean residence time of the particles in the sea of 56 days is estimated, prior to their being decomposed by bacterial action or settling to the bottom. for sewage derived N (as ammonia or nitrate), the steady state amount (above background) covers an area of about 60 km2 and leads to a mean residence time of 5 ± 1 days in the ocean. Phosphorus is readily absorbed by the phytoplankton. The presence of temperature gradients established by cold upwelling waters controls the dispersion of the sewage material and the rising of the sewage plume to the surface waters. 相似文献
706.
程锦晖 《石油化工环境保护》2001,24(1):24-27
电子束法是一种能够同时脱硫、脱硝的烟气处理方法,具有脱硫、脱硝率高,副产品能够有效综合利用,不产生二次污染的特点,是一种先进的烟气处理技术。 相似文献
707.
The global pet trade is a major risk to biodiversity and humans and has become increasingly globalized, diversified, digitalized, and extremely difficult to control. With billions of internet users posting online daily, social media could be a powerful surveillance tool. But it is unknown how reliably social media can track the global pet trade. We tested whether Instagram data predicted the geographic distribution of pet stores and the taxonomic composition of traded species in the emerging pet trade in ants (Hymenoptera, Formicidae). We visited 138 online stores selling ants as pets worldwide and recorded the species traded. We scraped ∼38,000 Instagram posts from ∼6300 users referencing ants as pets and analyzed comments on post and geolocation (available for ∼1800 users). We tested whether the number of Instagram users predicted the number of ant sellers per country and whether the species referenced as pets on Instagram matched the species offered in online stores, with a particular focus on invasive species. The location of Instagram users referencing ants as pets predicted the location of ant sellers across the globe (R2 = 0.87). Instagram data detected 439 of the 631 ant species traded in online stores (70%), including 59 of the 68 invasive species traded (87%). The number of Instagram users referencing a species was a good predictor of the number of sellers offering the species (R2 = 0.77). Overall, Instagram data provided affordable and reliable data for monitoring the emerging pet trade in ants. Easier access to these data would facilitate monitoring of the global pet trade and help implement relevant regulations in a timely manner. 相似文献
708.
Alice C. Hughes 《Conservation biology》2019,33(4):883-894
China's Belt and Road Initiative (BRI) sets to create connections and build infrastructure across Eurasia, Asia, and parts of the African continent in its initial phase and is the largest infrastructure project of all time. Any infrastructure project on this scale will necessarily pass through ecofragile regions and key biodiversity areas (KBAs). This creates an imperative to identify possible areas of impact and probable effects on conservation values to facilitate adaptive planning and to mitigate, minimize, or avoid impacts. Using the highest resolution route maps of the BRI available, I overlaid the proposed road and rail routes on KBAs, protected areas, and predicted biodiversity hotspots for over 4138 animal and 7371 plant species. I also assessed the relationship between the proposed route with the distribution of mines across BRI countries and the proportion of deforestation and forest near routes. Infrastructure, especially mining, was clustered near the proposed route; thus, construction and development along the route may increase the size and number of mines. Up to 15% of KBAs were within 1 km of proposed railways. Thus, planned and probable development along the routes may pose a significant risk to biodiversity, especially because the majority of KBAs are unprotected. Many biodiversity hotspots for different taxa were near the route. These hotspots varied between taxa, making systematic management and environmental impact assessments an effective strategy for at least some taxa. A combination of planning and mitigation strategies will likely be necessary to protect the most important areas for biodiversity proximal to development, especially in currently unprotected KBAs and other regions that need protection. A fuller assessment of trade-offs between conservation and other values will be necessary to make good decisions for each project and site being developed, including potentially modifying parts of the route to minimize impacts. Modification or foregoing of infrastructure may be needed if stakeholders consider the conservation costs too high. 相似文献
709.
SHANNON M. BARBER‐MEYER 《Conservation biology》2010,24(4):918-923
Abstract: Illegal international trade in wildlife (excluding fisheries and timber) has been valued at more than US$20 billion. A more precise figure has not been determined in part because of the clandestine nature of the trade, and for this same reason even regional and local levels of wildlife trade are difficult to assess. The application of recent developments in wildlife field‐survey methods (e.g., occupancy) now allows for a more‐accurate estimation of wildlife trade occurrence, including its hidden components at a variety of scales (e.g., regional, local) and periods (e.g., single season, 1 year, multiple years). Occupancy models have been applied in wildlife field studies to address the problem of false absences when conducting presence–absence surveys. Occupancy surveys differ from traditional presence–absence surveys because they incorporate repeat surveys, allowing for the likelihood of detecting a species (the probability of detection) to be estimated explicitly (in contrast to traditional surveys that often incorrectly treat this probability as close to one to allow for estimation of presence). Occupancy methods can be applied to a variety of wildlife‐trade surveys, including, for example, single‐species availability, links between two illegally traded species (i.e., co‐occurrence), and disease occurrence in live trade. In addition, free user‐friendly software (i.e., PRESENCE) allows even nonstatisticians to adequately address this issue. I simulated a hypothetical wildlife‐trade market survey that resulted in an apparent 20% decline in naïve occupancy (proportion of surveyed towns engaged in the trade) over 2 years, but when I accounted for change in probability of detection over the years the difference in occupancy was not statistically significant. As more sophisticated methods, such as occupancy, are applied to wildlife‐trade market surveys, results will be more robust and defensible and therefore, theoretically, more powerful when presented to conservation policy and decision makers. 相似文献
710.
Systematic reviews comprehensively summarize evidence about the effectiveness of conservation interventions. We investigated the contribution to management decisions made by this growing body of literature. We identified 43 systematic reviews of conservation evidence, 23 of which drew some concrete conclusions relevant to management. Most reviews addressed conservation interventions relevant to policy decisions; only 35% considered practical on‐the‐ground management interventions. The majority of reviews covered only a small fraction of the geographic and taxonomic breadth they aimed to address (median = 13% of relevant countries and 16% of relevant taxa). The likelihood that reviews contained at least some implications for management tended to increase as geographic coverage increased and to decline as taxonomic breadth increased. These results suggest the breadth of a systematic review requires careful consideration. Reviews identified a mean of 312 relevant primary studies but excluded 88% of these because of deficiencies in design or a failure to meet other inclusion criteria. Reviews summarized on average 284 data sets and 112 years of research activity, yet the likelihood that their results had at least some implications for management did not increase as the amount of primary research summarized increased. In some cases, conclusions were elusive despite the inclusion of hundreds of data sets and years of cumulative research activity. Systematic reviews are an important part of the conservation decision making tool kit, although we believe the benefits of systematic reviews could be significantly enhanced by increasing the number of reviews focused on questions of direct relevance to on‐the‐ground managers; defining a more focused geographic and taxonomic breadth that better reflects available data; including a broader range of evidence types; and appraising the cost‐effectiveness of interventions. Contribuciones de las Revisiones Sistemáticas a las Decisiones de Manejo 相似文献