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281.
Eucalyptus albens (White Box) woodlands are among the most poorly conserved and threatened communities in Australia. Remnants are under further
threat from stock grazing, deteriorating soil conditions, weed invasion, and salinity. There is an urgent need to restore
degraded White Box and other woodland ecosystems to improve landscape function. However, there is still a poor understanding
of the ecology of degraded woodland ecosystems in fragmented agricultural landscapes, and consequently a lack of precise scientific
guidelines to manage these ecosystems in a conservation context. State and Transition Models (STMs) have received a great
deal of attention, mainly in rangeland applications, as a suitable framework for understanding the ecology of complex ecosystems
and to guide management. We have developed a STM for endangered White Box woodlands and discuss the merits of using this approach
for land managers of other endangered ecosystems. An STM approach provides a greater understanding of the range of states,
transitions, and thresholds possible in an ecosystem, and provides a summary of processes driving the system. Importantly,
our proposed STM could be used to clarify the level of “intactness” of degraded White Box woodland sites, and provide the
impetus to manage different states in complementary ways, rather than attempting to restore ecosystems to one pristine stable
state. We suggest that this approach has considerable potential to integrate researcher and land manager knowledge, focus
future experimental studies, and ultimately serve as a decision support tool in setting realistic and achievable conservation
and restoration goals. 相似文献
282.
283.
Conservation planning aims to protect biodiversity by sustainng the natural physical, chemical, and biological processes within
representative ecosystems. Often data to measure these components are inadequate or unavailable. The impact of human activities
on ecosystem processes complicates integrity assessments and might alter ecosystem organization at multiple spatial scales.
Freshwater conservation targets, such as populations and communities, are influenced by both intrinsic aquatic properties
and the surrounding landscape, and locally collected data might not accurately reflect potential impacts. We suggest that
changes in five major biotic drivers—energy sources, physical habitat, flow regime, water quality, and biotic interactions—might
be used as surrogates to inform conservation planners of the ecological integrity of freshwater ecosystems. Threats to freshwater
systems might be evaluated based on their impact to these drivers to provide an overview of potential risk to conservation
targets. We developed a risk-based protocol, the Ecological Risk Index (ERI), to identify watersheds with least/most risk
to conservation targets. Our protocol combines risk-based components, specifically the frequency and severity of human-induced
stressors, with biotic drivers and mappable land- and water-use data to provide a summary of relative risk to watersheds.
We illustrate application of our protocol with a case study of the upper Tennessee River basin, USA. Differences in risk patterns
among the major drainages in the basin reflect dominant land uses, such as mining and agriculture. A principal components
analysis showed that localized, moderately severe threats accounted for most of the threat composition differences among our
watersheds. We also found that the relative importance of threats is sensitive to the spatial grain of the analysis. Our case
study demonstrates that the ERI is useful for evaluating the frequency and severity of ecosystemwide risk, which can inform
local and regional conservation planning. 相似文献
284.
Christina A. Holcroft Author Vitae Laura Punnett Author Vitae 《Journal of Safety Research》2009,40(4):247-3552
Problem
The reported injury rate for wood product manufacturing in Maine, 1987-2004, was almost twice the state-wide average for all jobs. Method: A case-control study was conducted in wood processing plants to determine preventable risk factors for injury. A total of 157 cases with injuries reported to workers' compensation and 251 controls were interviewed. Results: In multivariable analyses, variables associated with injury risk were high physical workload, machine-paced work or inability to take a break, lack of training, absence of a lockout/tagout program, low seniority, and male gender. Different subsets of these variables were significant when acute incidents and overexertions were analyzed separately and when all injuries were stratified by industry sub-sector. Impact on industry: Generalizability may be limited somewhat by non-representative participation of workplaces and individuals. Nevertheless, these findings provide evidence that many workplace injuries occurring in wood processing could be prevented by application of ergonomics principles and improved work organization. 相似文献285.
Dirac Twidwell Carissa L. Wonkka Christine H. Bielski Craig R. Allen David G. Angeler Jacob Drozda Ahjond S. Garmestani Julia Johnson Larkin A. Powell Caleb P. Roberts 《Conservation biology》2018,32(4):905-915
A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus. 相似文献
286.
Biodiversity conservation has been criticized for undermining or ignoring social well‐being. Currently efforts to mutually promote social justice, rural development, and biodiversity conservation, which have been contentious and yielded mixed results, continue to spread despite a general dearth of effective management strategies. We contend that social and economic concerns should be integral to conservation planning and propose that the scale of these phenomena is also critical. To evaluate the merit of this proposal, we adopted and expanded a conservation management strategy framework developed by Joel Heinen and examined how population density, economic disparity, and ethnic heterogeneity vary spatially surrounding 2 contrasting protected areas in East Africa: Kibale National Park in Uganda and Tarangire National Park in Tanzania. Analyses of demographic, wealth, and ethnicity data from regional censuses and household surveys conducted in 2009 and 2010 indicated that choice of scale (landscape or community) changed the management strategies recommended by the model. Therefore, “several small” people?park management strategies varying around a given protected area may be more appropriate than a “single large” people–park strategy applied across an entire protected area. Correspondingly, scale adjusted Heinen recommendations offered new strategies for effective conservation management within these human landscapes not incorporated in current in situ management plans. Uso de Varias Políticas Pequeñas o una Única Política Mayor como Estrategias para Manejar las Interacciones Gente – Parque 相似文献
287.
Jesper Slver Schou Jesper Bladt Rasmus Ejrns Maria Nygrd Thomsen Suzanne Elizabeth Vedel Camilla Fljgaard 《Ambio》2021,50(5):1047
Policies aiming at improving biodiversity often consist of costly agri-environmental schemes, i.e. subsidized grazing or mowing of semi-natural areas. However, these practices have widely been found to be insufficient to mitigate biodiversity loss. Rewilding, i.e. restoring natural processes in self-sustaining biodiverse ecosystems, has been proposed as an alternative and is hypothesized to be a more cost-efficient approach to promote biodiversity conservation. Rewilding requires the availability of large natural areas which are not allocated for farming, forestry, and infrastructure to avoid potential conflicts over the use of the area. We perform an ex-ante private cost–benefit analysis of the establishment of four large nature reserves for rewilding in Denmark. We analyse the economic effects of changing from summer grazing in nature areas in combination with cultivated fields and forestry to the establishment of nature reserves in four case areas. We consider two scenarios involving conversion of agriculture and forestry areas into natural areas in combination with either extensive year-round cattle grazing or rewilding with wild large herbivores. In two case areas, it appears possible to establish large nature areas without incurring extra costs. Additionally, rewilding further reduces costs compared to year-round cattle grazing. Two opposing effects were dominant: increased economic rent occurred from the shift from summer grazing to year-round grazing or rewilding, while cessation of agriculture and forestry caused opportunity costs. 相似文献
288.
Online crowdfunding can help address the perennial financial shortfalls in environmental conservation and management. Although many online crowdfunding campaigns fail to collect any funds due to not achieving their targets, little is known about what drives success. To address this knowledge gap, we applied a mixed-methods approach to data from 473 successful and failed campaigns hosted on the online crowdfunding platform Readyfor. We found that fundraising performance varied by topic, with campaigns on pet animal management outperforming those focussed on landscape management and sustainable use. We also found that marketing strategies associated with online findability and increased reach through social networks, increased fundraising success. However, the existence of other environmental campaigns running simultaneously, reduced the chance of success, which implies that the selecting popular topics does not always increase the likelihood of success due to increased competition. Wider applications of marketing could enhance the ability of environmental crowdfunding campaigns to raise funds.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01522-0. 相似文献
289.
Caitlin A. Grady Adam P. Reimer Jane Frankenberger Linda Stalker Prokopy 《Journal of the American Water Resources Association》2013,49(4):883-895
There is an increasing need to document the impacts of conservation‐related best management practices (BMPs) on water quality within a watershed. However, this impact analysis depends upon accurate geospatial locations of existing practices, which are difficult to obtain. This study demonstrates and evaluates three different methods for obtaining geospatial information for BMPs. This study was focused on the Eagle Creek Watershed, a mixed use watershed in central Indiana. We obtained geospatial information for BMPs through government records, producer interviews, and remote‐sensing aerial photo interpretation. Aerial photos were also used to validate the government records and producer interviews. This study shows the variation in results obtained from the three sources of information as well as the benefits and drawbacks of each method. Using only one method for obtaining BMP information can be incomplete, and this study demonstrates how multiple methods can be used for the most accurate picture. 相似文献
290.
《Environmental Communication: A Journal of Nature and Culture》2013,7(4):406-421
Successful conservation efforts require understanding predictors of private-land stewardship (PLS), its definitions, and what people feel they owe stewardship responsibility to. Various strands of research have touched on the concept, but there is little research focusing on how it is communicated and enacted among the lay public, especially among Latinos. We used a case study in the Lower Rio Grande Valley of Texas to address this gap by identifying and assessing Latino views of PLS. Our results indicate positive relationships between self-identification as a land steward, male gender, and agricultural-land ownership. Respondents associated PLS with property maintenance (60%), natural-resource conservation (14%), and addressing pollution problems (21%). They viewed PLS as a responsibility owed to family rather than to a larger community. 相似文献