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641.
Integrated conservation and development projects (ICDPs) have been a pervasive, although widely criticized, approach to tropical conservation for more than 20 years. More recently, international conservation discourse has shifted away from project-based approaches and towards reducing emissions from deforestation and forest degradation (REDD). While REDD is based upon experience with payment for environmental services (PES) initiatives and forest-related discussions in the United Nations (UN), REDD implementation will still require sub-national projects. Issues of equity will likely pit these sub-national projects against some of the same challenges that have dogged ICDPs. This suggests that REDD project developers stand to learn a great deal from the lessons generated by experience with ICDPs. This paper provides a list of best practices for ICDPs and applies their lessons as principles to guide the development and implementation of sub-national REDD projects. The intent of this approach is to encourage the design and implementation of sub-national REDD projects in a way that avoids the past pitfalls and mistakes, while building upon some successes, of the ICDP conservation approach. By doing so, REDD will be more likely to be implemented in a way that is effective, efficient and equitable. 相似文献
642.
Teresa I. Schueller Erik V. Nordheim Benjamin J. Taylor Robert L. Jeanne 《Die Naturwissenschaften》2010,97(11):1017-1022
This study explores whether or not foragers of the Neotropical swarm-founding wasp Polybia occidentalis use nest-based recruitment to direct colony mates to carbohydrate resources. Recruitment allows social insect colonies to rapidly exploit ephemeral resources, an ability especially advantageous to species such as P. occidentalis, which store nectar and prey in their nests. Although recruitment is often defined as being strictly signal mediated, it can also occur via cue-mediated information transfer. Previous studies indicated that P. occidentalis employs local enhancement, a type of cue-mediated recruitment in which the presence of conspecifics at a site attracts foragers. This recruitment is resource-based, and as such, is a blunt recruitment tool, which does not exclude non-colony mates. We therefore investigated whether P. occidentalis also employs a form of nest-based recruitment. A scented sucrose solution was applied directly to the nest. This mimicked a scented carbohydrate resource brought back by employed foragers, but, as foragers were not allowed to return to the nest with the resource, there was no possibility for on-nest recruitment behavior. Foragers were offered two dishes—one containing the test scent and the other an alternate scent. Foragers chose the test scent more often, signifying that its presence in the nest induces naïve foragers to search for it off-nest. P. occidentalis, therefore, employs a form of nest-based recruitment to carbohydrate resources that is mediated by a cue, the presence of a scented resource in the nest. 相似文献
643.
While foraging, social insects encounter a dynamic array of food resources of varying quality and profitability. Because food
acquisition influences colony growth and fitness, natural selection can be expected to favor colonies that allocate their
overall foraging effort so as to maximize their intake of high-quality nutrients. Social wasps lack recruitment communication,
but previous studies of vespine wasps have shown that olfactory cues influence foraging decisions. Odors associated with food
brought into the nest by successful foragers prompt naive foragers to leave the nest and search for the source of those odors.
Left unanswered, however, is the question of whether naive foragers take food quality into account in making their decisions
about whether or not to search. In this study, two different concentrations of sucrose solutions, scented differently, were
inserted directly into each of three Vespula germanica nests. At a feeder away from the nest, arriving foragers were given a choice between two 1.5 M sucrose solutions with the
same scents as those in the nest. We show that wasps chose higher-quality resources in the field using information in the
form of intranidal food-associated odor cues. By this simple mechanism, the colony can bias the allocation of its foraging
effort toward higher-quality resources in the environment. 相似文献
644.
Randolf Menzel Jacqueline Fuchs Leonard Nadler Benjamin Weiss Nicole Kumbischinski Daniel Adebiyi Sergej Hartfil Uwe Greggers 《Die Naturwissenschaften》2010,97(8):763-767
Honeybees use their visual flow field to measure flight distance. It has been suggested that the experience of serial landmarks
encountered on the flight toward a feeding place contributes to distance estimation. Here, we address this question by tracing
the flight paths of individual bees with a harmonic radar system. Bees were trained along an array of three landmarks (tents),
and the distance between these landmarks was either increased or decreased under two test conditions. We find that absolute
distance estimation dominates the search for the feeding place, but serial position effects are also found. In the latter
case, bees search only or additionally at locations determined by serial experience of the landmarks. 相似文献
645.
Fok TF Lam HS Ng PC Yip AS Sin NC Chan IH Gu GJ So HK Wong EM Lam CW 《Environment international》2007,33(1):84-92
This study was designed to examine newborn infants in Hong Kong prenatally exposed to levels of methylmercury considered to increase risk of neurotoxic effects and to examine subject characteristics that modify the degree of prenatal mercury exposure. Mercury concentrations in 1057 sets of maternal and cord blood samples and 96 randomly selected maternal hair samples were measured. Subject characteristics were measured or collected by questionnaire. Of the 1057 cord blood samples collected only 21.6% had mercury concentrations less than 29 nmol/L (5.8 micro g/L). Median maternal hair mercury concentration was 1.7 ppm. The geometric mean cord to maternal blood mercury ratio was 1.79 to 1. Increasing maternal fish consumption and maternal age were found to be associated with increased cord blood mercury concentrations. Marine fish consumption increased cord blood mercury concentrations more than freshwater fish (5.09%/kg vs 2.86%/kg). Female babies, maternal alcohol consumption and increasing maternal height were associated with decreased cord blood mercury concentrations. Pregnant women in Hong Kong consume large amounts of fish and as a result, most of their offspring have been prenatally exposed to moderately high levels of mercury. In this population, pregnant women should choose freshwater over marine fish and limit fish consumption. 相似文献
646.
Climate adaptation planning in practice: an evaluation of adaptation plans from three developed nations 总被引:5,自引:2,他引:3
Benjamin?L.?PrestonEmail author Richard?M.?Westaway Emma?J.?Yuen 《Mitigation and Adaptation Strategies for Global Change》2011,16(4):407-438
Formal planning for climate change adaptation is emerging rapidly at a range of geo-political scales. This first generation
of adaptation plans provides useful information regarding how institutions are framing the issue of adaptation and the range
of processes that are recognized as being part of an adaptation response. To better understand adaptation planning among developed
nations, a set of 57 adaptation plans from Australia, the United Kingdom and the United States was evaluated against a suite
of 19 planning processes identified from existing guidance instruments for adaptation planning. Total scores among evaluated
plans ranged from 16% of the maximum possible score to 61%, with an average of 37%. These results suggest adaptation plans
are largely under-developed. Critical weaknesses in adaptation planning are related to limited consideration for non-climatic
factors as well as neglect for issues of adaptive capacity including entitlements to various forms of capital needed for effective
adaptation. Such gaps in planning suggest there are opportunities for institutions to make better use of existing guidance
for adaptation planning and the need to consider the broader governance context in which adaptation will occur. In addition,
the adaptation options prescribed by adaptation plans reflect a preferential bias toward low-risk capacity-building (72% of
identified options) over the delivery of specific actions to reduce vulnerability. To the extent these findings are representative
of the state of developed nation adaptation planning, there appear to be significant deficiencies in climate change preparedness,
even among those nations often assumed to have the greatest adaptive capacity. 相似文献
647.
Impact of ultrasonication(ULS) and ultrasonication–ozonation(ULS-Ozone) pre-treatment on the anaerobic digestibility of sewage sludge was investigated with semi-continuous anaerobic reactors at solid retention time(SRT) of 10 and 20 days. The control, ULS and ULS-Ozone reactors produced 256, 309 and 348 m L biogas/g CODfedand the volatile solid(VS) removals were 35.6%, 38.3% and 42.1%, respectively at SRT of 10 days. At SRT of20 days, the biogas yields reached 313, 337 and 393 m L biogas/g CODfedand the VS removal rates were 37.3%, 40.9% and 45.3% in the control, ULS and ULS-Ozone reactors, respectively.ULS-Ozone pre-treatment increased the residual organic amount in the digested sludge.These soluble residual organics were found to contain macromolecules with molecular weights(MW) larger than 500 k Da and smaller polymeric products with MW around 19.4and 7.7 k Da. These compounds were further characterized to be humic acid-like substances with fluorescent spectroscopy analysis. 相似文献
648.
Ultrafine particles are associated with adverse health effects. Total Particle Number Concentration (TNC) of fine particles were measured during 2002 at the St. Louis — Midwest supersite. The time series showed overall low level with frequent large peaks. The time series was analyzed alongside criteria pollutant measurements and meteorological observations. Multiple regression analysis was used to identify further contributing factors and to determine the association of different pollutants with TNC levels. This showed the strong contribution of sulfur dioxide (SO2) and nitrogen oxides (NOx) to high TNC levels. The analysis also suggested that increased dispersion resulting from faster winds and higher mixing heights led to higher TNC levels. Overall, the results show that there were intense particle nucleation events in a SO2 rich plume reaching the site which contributed around 29% of TNC. A further 40% was associated with primary emissions from mobile sources. By separating the remaining TNC by time of day and clear sky conditions, we suggest that most likely 8% of TNC are due to regional nucleation events and 23% are associated with the general urban background. 相似文献
649.
Environmental Science and Pollution Research - Cremation is commonly practiced around the world because it requires small space for the disposal of ashes. Among various options for ash disposal,... 相似文献
650.
Environmental Chemistry Letters - Climate change damage induced by growing carbon dioxide (CO2) emissions has rapidly fostered research on capturing, utilizing, and converting CO2 into valuable C1... 相似文献