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591.
María E. Ibarrarán Elizabeth L. Malone Antoinette L. Brenkert 《Environment, Development and Sustainability》2010,12(3):365-388
Climate change alters different localities on the planet in different ways. The impact on each region depends mainly on the
degree of vulnerability that natural ecosystems and human-made infrastructure have to changes in climate and extreme meteorological
events, as well as on the coping and adaptation capacity toward new environmental conditions. This study assesses the current
resilience of Mexico and Mexican states to such changes, as well as how this resilience will look in the future. In recent
studies (Moss et al. in Vulnerability to climate change: a quantitative approach. Pacific Northwest National Laboratory, Washington
DC, 2001; Brenkert and Malone in Clim Change 72:57–102, 2005; Malone and Brenkert in Clim Change 91:451–476, 2008), the Vulnerability–Resilience Indicators Model (VRIM) is used to integrate a set of proxy variables that determine the resilience
of a region to climate change. Resilience, or the ability of a region to respond to climate variations and natural events
that result from climate change, is given by its adaptation and coping capacity and its sensitivity. On the one hand, the
sensitivity of a region to climate change is assessed, emphasizing its infrastructure, food security, water resources, and
the health of the population and regional ecosystems. On the other hand, coping and adaptation capacity is based on the availability
of human resources, economic capacity, and environmental capacity. This paper presents two sets of results. First, we show
the application of the VRIM to determine state-level resilience for Mexico, building the baseline that reflects the current
status. The second part of the paper makes projections of resilience under socioeconomic and climate change and examines the
varying sources and consequences of those changes. We used three tools to examine Mexico’s resilience in the face of climate
change, i.e., the baseline calculations regarding resilience indices made by the VRIM, the projected short-term rates of socioeconomic
change from the Boyd–Ibarrarán computable general equilibrium model, and rates of the IPCC-SRES scenario projections from
the integrated assessment MiniCAM model. This allows us to have available change rates for VRIM variables through the end
of the twenty-first century. 相似文献
592.
Livestock production in both industrial systems, where livestock are packed tightly together, and in highly traditional systems,
where a shepherd follows her herd in dispersed rangelands, are cited as key contributors in some of the most acute environmental
problems around the globe. Israel is one of the few countries where both of these systems exist, with surprisingly little
contact between them. The environmental impact of the sectors were examined along with Israel’s public policies in the field.
While historically, much attention has been placed on the contribution of the Bedouin pastoralists to desertification and
erosion, this may be linked to historic misapprehension about actual impacts of goats on local rangelands as well as political
motivations and concerns about losing national sovereignty over large areas of rangelands. The true environmental effects
appear to be minor. A far more critical concern is water pollution caused by the industrial sector of livestock production—an
issue that recently has attracted considerable government attention and investment in a successful dairy infrastructure initiative.
The divisions between governmental supports for the Jewish and Arab sectors of livestock management are inconsistent with
efficient environmental management. Policies should be designed to encourage Bedouin to find ways to sustainably continue
their traditional livestock husbandry practises, which today are largely associated with ecological benefits and constitute
a unique cultural asset for Israel and the world. 相似文献
593.
Correa-Reyes G Viana MT Marquez-Rocha FJ Licea AF Ponce E Vazquez-Duhalt R 《Chemosphere》2007,68(4):662-670
Nonylphenol is a metabolic intermediate from the microbial transformation of detergents used worldwide. While nonylphenol shows some acute toxicity, it is also able to mimic important hormones resulting in the disruption of several processes by interfering with the signals that control the overall physiology of the organism. The effect of the pollutant nonylphenol (NP) through the trophic chain was studied. Microalgae Isochrysis galbana was able to bioconcentrate NP 6940 times, where 77% of initial NP (100microgl(-1)) is accumulated intracellularly after 1-h incubation. Crustacean Artemia fransiscana showed 25% higher growth when fed with NP-rich algae. However, Artemia metabolized almost all NP ingested and only traces of NP could be found in the organism, eliminating future NP effects. Zebrafish (Brachydanio rerio) were affected by the presence of 171microgg(-1) of NP in the diet, showing higher levels of the hormone vitellogenin and lower levels of cytochrome P450 activity. These results showed that organisms placed in the first level of trophic chain are able to significantly bioconcentrate the pollutant and endocrine disruptor NP. These grassed organisms affect the growth of crustacean. Moreover, the organisms placed on the top of some trophic chains, such as fish, could be affected by the presence of NP in their food, in both the hormone levels and metabolic enzymes. This work shows that the environmental presence of NP should be considered as a risk for the organisms living in an ecosystem. 相似文献
594.
The USDA Forest Service, Forest Inventory and Analysis program (FIA) recently produced a nationwide map of forest biomass
by modeling biomass collected on forest inventory plots as nonparametric functions of moderate resolution satellite data and
other environmental variables using Cubist software. Efforts are underway to develop methods to enhance this initial map.
We explored the possibility of modeling spatial structure to make such improvements. Spatial structure in the field biomass
data as well as in residuals from the map was investigated across 18 ecological zones in the Interior Western U.S. Exploratory
tools included directional graphs of summary statistics, three dimensional maps, Moran’s I correlograms, and variograms. Where
spatial pattern was present, field and residual biomass were kriged, and predictions made for an independent test set were
evaluated for improvement over predictions in the initial biomass map. While kriging has some potential benefit when analyzing
the field data and exploring spatial structure, kriging residuals resulted in little or no improvement in the initial biomass
map developed using Cubist software. Stationarity assumptions, variogram behavior, and appropriate model fitting strategies
are discussed. 相似文献
595.
María A. Rubio Irene Fuenzalida Elizabeth Salinas Eduardo Lissi Ralf Kurtenbach Peter Wiesen 《Environmental monitoring and assessment》2010,162(1-4):209-217
CO/CO2 ratios have been measured in different locations of Santiago de Chile city. Measurements were carried out in a tunnel (prevailing emissions from cars with catalytic converter) and close to heavy traffic streets. Concentrations measured along the city traffic tunnel or temporal profiles of concentrations measured near heavy traffic streets allow an estimation of CO/CO2 ratios emitted from mobile sources. Values obtained range from 0.0045 ± 0.0006 to 0.0100 ± 0.0004 and depend on the prevailing type of mobile sources. In particular, lowest values were found close to a street with heavy traffic dominated by diesel-powered public transportation, while the highest values were found at the city tunnel. Places located near streets of mixed mobile sources (public buses and cars) showed intermediate values. Average CO/CO2 ratios are compatible with emission factors proposed for Santiago’s main mobile sources. 相似文献
596.
Contemporary estimates of atmospheric nitrogen deposition to the watersheds of New York State, USA 总被引:1,自引:0,他引:1
Atmospheric inputs of reactive nitrogen (N) to ecosystems are a particular concern in the northeastern USA, including New York State, where rates of atmospheric N deposition are among the highest in the nation. We calculate the seasonal and annual spatial variations of contemporary inorganic atmospheric N deposition loading to multi-scale watersheds across New York State using numerous monitoring datasets of precipitation and ambient atmospheric N concentrations. Our models build upon and refine previous efforts estimating the spatial distribution of N deposition. Estimates of total inorganic wet deposition (NH4-N + NO3-N) across New York ranged from 4.7 to 10.5 kg ha(-1) yr(-1) under contemporary conditions (averaged 2002-2004), and both seasonal and annual predicted rates of inorganic N deposition (NH4-N, NO3-N, and total) fit relatively well with that of observed measurements. Our results suggest that "hot spots" of N deposition are, for the most part, spatially distributed according to geographic positions (i.e., relative location from sources and the Great Lakes system) and elevation. We also detect seasonal variations in deposition, showing that total wet atmospheric inorganic N deposition inputs to watersheds (extracted from the four-digit HUC calculations) are highest during the spring (mean = 2.4 kg ha(-1), stddev = 0.29) and lowest during the winter months (mean = 1.4 kg ha(-1), stddev = 0.23). Results also suggest that wet NO3(-) consistently comprises a slightly higher proportion of wet N deposition than wet NH4+ throughout watersheds of New York, ranging from 2.5 to 6.1 kg NO3-N ha(-1) yr(-1) compared to NH4+, which ranges from 2.2 to 4.4 kg NH4-N ha(-1) yr(-1). 相似文献
597.
Elizabeth R. Smith 《Environmental monitoring and assessment》2000,64(1):9-15
Regional Vulnerability Assessment (ReVA) is an approach to place-based ecological risk assessment that is currently under development by EPA's Office of Research and Development. The pilot assessment will be done for the mid-Atlantic region and builds on data collected for the Environmental Monitoring and Assessment Program. ReVA is being developed to identify those ecosystems most vulnerable to being lost or degraded in the next 5 to 50 years and to elucidate which stressors cause the greatest risk to ecosystem goods and services. The goal here is not exact predictions, but an early warning system to identify and prioritize the undesirable environmental changes we should expect over the next few decades. As such, ReVA represents a new risk paradigm for EPA that will require innovative approaches to combine existing knowledge, focus new research, and synthesize many types of information into a meaningful assessment designed to inform environmental decision-makers about future environmental risk. 相似文献
598.
Elizabeth B. Connelly Craig R. Allen Kirk Hatfield José M. Palma-Oliveira David D. Woods Igor Linkov 《The Environmentalist》2017,37(1):46-50
The National Academy of Sciences (NAS) definition of resilience is used here to organize common concepts and synthesize a set of key features of resilience that can be used across diverse application domains. The features in common include critical functions (services), thresholds, cross-scale (both space and time) interactions, and memory and adaptive management. We propose a framework for linking these features to the planning, absorbing, recovering, and adapting phases identified in the NAS definition. The proposed delineation of resilience can be important in understanding and communicating resilience concepts. 相似文献
599.
The dominant discourse in 20th century UK food and agricultural policies of a liberal, free trade agenda was modified at the
turn of the 21st to embrace ecological sustainability and “food security.” The latter term has a long international history;
the relationship between issues of technical production and equality of distributional access are also much debated. The paper
examines shifts in UK policy discourse in the context of international research, policy, and initiatives to promote food security,
and highlights the implications for social justice in and through the food system. 相似文献
600.
While the age of physical environments is the central tenet of historic preservation, there is a lack of empirical evidence about how everyday people actually value, perceive, and experience age as an intrinsic part of an urban environment. In order to ameliorate this knowledge deficit, this study employs phenomenology to understand the lived experience of being in a “new” versus an “old” or “historic” urban residential environment. The new environment is the I'On new urbanist development in Mt. Pleasant, South Carolina, and the old environment is the location of the United States' first historic district in Charleston, South Carolina. These locations are approximately within five miles of each other. In both places, the physical characteristics of the built environment are remarkably similar in density, form, layout, and design, but the age is dramatically different. Through photo elicitation techniques and interviews, the results of this study reveal that residents of historic Charleston and I'On value their built environments in remarkably similar ways. Surprisingly, elements that evoke a strong sense of attachment tend to be landscape features, such as gates, fountains, trees, and gardens rather than buildings. The informants valued the “mystery” that they felt was part of the landscape and which consisted of layered elements such as fences, gates, and paths, such that these features (including buildings) had to be “discovered.” Lastly, the informants strongly valued landscapes that showed “people care” through regular maintenance. The essential difference in people's experience and valuation of the new environment (I'On) and the old environment (historic Charleston) is in the older environment's ability to instill creative fantasies in the minds of the informants based on a hypothetical past of their own creation. The informants in I'On did not share these kinds of meanings. 相似文献