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51.
Family insurance: kin selection and cooperative breeding in a solitary primate (Microcebus murinus) 总被引:1,自引:0,他引:1
Lactation imposes substantial physiological costs on mothers and should therefore not be directed towards foreign offspring. Such allonursing, however, is common in mammal species that share roosts. Hypotheses to explain allonursing among such plural breeders include misdirected parental care, milk evacuation, brood parasitism, reciprocity, and kin selection. The necessary behavioral data, in combination with data on kinship and kin recognition, have rarely been available to distinguish among these explanations, however. In this study, we provide evidence for cooperative nursing and adoption by plural-breeding females in a nocturnal primate, the gray mouse lemur (Microcebus murinus), in which females forage solitarily during the night, but form day-time sleeping groups with one to two other females. We observed 34 resident females in an 8 ha study area in Kirindy Forest, Madagascar, over three consecutive annual breeding seasons and determined genetic relationships among all members of this population. Five sleeping groups of adult females were filmed inside their roosts during one breeding season after females gave birth. The composition of groups changed substantially across years, but they always consisted of close maternal relatives. All females within a group gave birth to one to three infants. They regularly transferred only their own offspring among roosting sites, demonstrating an ability to discriminate between their own and other’s offspring, but they regularly groomed and nursed related offspring other than their own and adopted related dependent young after their mother’s death. Kin selection may therefore be the main selective force behind cooperative breeding among these closely related females with a high mortality risk, providing each of them with family insurance. 相似文献
52.
Elena P. Kruchenkova Michael Goltsman Sergei Sergeev David W. Macdonald 《Die Naturwissenschaften》2009,96(4):457-466
The Arctic Fox Alopex lagopus semenovi population on Mednyi Island is completely isolated and subsists largely by scavenging on seabird colonies, which have remained
abundant and spatio-temporally predictable for many years. We compared population data at the beginning of 1976/1978 and some
time after 1994–2005, finding an 85% decline in fox numbers due to disease, to assess the effect of population size on social
structure. A total of 81 groups of known size and composition was observed during this 29-year period. Overall, helpers (usually
non-lactating yearling females) occurred in 25.7% of groups, and in 32.4% of groups there were two or three lactating females.
Female engagement in alloparental behaviour decreased, but not statistically significantly, after the decline in population
density. Total food availability was apparently constant throughout the study period, and therefore, the amount available
per individual was much higher later in the study. Both communally nursing females and helpers brought food and helped to
guard the litter. However, the benefits of communal rearing were unclear. While cubs were left without guards significantly
more rarely in the groups with an additional adult, the number of cubs weaned per lactating female was greater in groups with
one (3.93 ± 1.60), as opposed to two or three (3.06 ± 0.92), lactating females. Survival of cubs to 1 year of age in the groups
with two lactating females and/or with helpers was lower than that in the families with one lactating female without helpers (22.2% vs 32.2%). Fewer second-generation litters were
born to foxes produced by composite families than to those produced by pairs. Reproductive adults producing by pairs had,
on average, 1.23 (±1.72) second-generation litters. In groups that initially included additional adults, the average number
of second-generation litters per reproductive female was 0.21 (±0.49) and 0.46 (±0.81) litters per male. Thus, according to
three measures, increased group size had no apparent positive impact on reproductive success. The increased parental investment
and enhanced guarding of the cubs in the larger families could be beneficial under conditions of high population density and
a saturated biotope to which the island fox population was presumably adapted before the population crash in the late 1970s. 相似文献
53.
Devolution of responsibilities is transforming how flood risk is managed in many countries. Research assessing the emergence and role of a new element in the governance of flood risk management in England explored the numerous ‘flood action groups’ that have developed over the last decade. We identified two broad categories of relationship between the public and authorities. The first displays ‘contractual’ characteristics: a level of protection provided by the authority in exchange for taxes or similar support. The second embodies a ‘collaborative’ relationship: public knowledge, social and financial resources are equal and complementary to those of authority, and seeking ‘collective security’. In general, the former were more successful than the latter, but common lessons were that success in FRM should not be defined purely as the ability to prevent flooding, but as the ability to access a variety of resources across different levels of society at different stages of flood risk management. 相似文献
54.
Different regulatory agencies in food and drug administration and environmental protection worldwide are employing quantitative structure-activity relationship (QSAR) models to fill the data gaps related with properties of chemicals affecting the environment and human health. Carcinogenicity is a toxicity endpoint of major concern in recent times. Interspecies toxicity correlations may provide a tool for estimating sensitivity towards toxic chemical exposure with known levels of uncertainty for a diversity of wildlife species. In this background, we have developed quantitative interspecies structure-carcinogenicity correlation models for rat and mouse [rodent species according to the Organization for Economic Cooperation and Development (OECD) guidelines] based on the carcinogenic potential of 166 organic chemicals with wide diversity of molecular structures, spanning a large number of chemical classes and biological mechanisms. All the developed models have been assessed according to the OECD principles for the validation of QSAR models. Consensus predictions for carcinogenicity of the individual compounds are presented here for any one species when the data for the other species are available. Informative illustrations of the contributing structural fragments of chemicals which are responsible for specific carcinogenicity endpoints are identified by the developed models. The models have also been used to predict mouse carcinogenicities of 247 organic chemicals (for which rat carcinogenicities are present) and rat carcinogenicities of 150 chemicals (for which mouse carcinogenicities are present). Discriminatory features for rat and mouse carcinogenicity values have also been explored. 相似文献
55.
Solar geoengineering has received increasing attention as an option to temporarily stabilize global temperatures. A key concern is that heterogeneous preferences over the optimal amount of cooling combined with low deployment costs may allow the country with the strongest incentive for cooling, the so-called free-driver, to impose a substantial externality on the rest of the world. We analyze whether the threat of counter-geoengineering technologies capable of negating the climatic effects of solar geoengineering can overcome the free-driver problem and tilt the game in favour of international cooperation. Our game-theoretical model of countries with asymmetric preferences allows for a rigorous analysis of the strategic interaction surrounding solar geoengineering and counter-geoengineering. We find that counter-geoengineering prevents the free-driver outcome, but not always with benign effects. The presence of counter-geoengineering leads to either a climate clash where countries engage in a non-cooperative escalation of opposing climate interventions (negative welfare effect), a moratorium treaty where countries commit to abstain from either type of climate intervention (indeterminate welfare effect), or cooperative deployment of solar geoengineering (positive welfare effect). We show that the outcome depends crucially on the degree of asymmetry in temperature preferences between countries. 相似文献
56.
Shan Weidong 《中国人口.资源与环境(英文版)》2013,11(2):58-62
Abstract This paper analyses redounded profits of cooperation and non-cooperation among cities in urban agglomerations based on game theory. It discusses the problems of economical development among cities with feeble cooperation, and deduces the conclusion that only cooperation of cities produces the maximum profits and realizes Pareto efficiency for cities and urban agglomerations. The paper states that cooperation is the cornerstone of economic sustainable development in urban agglomerations in profits produced by cooperation among cities. Some suggestions to accelerate cooperation among cities are proposed. 相似文献
57.
Most research on animal contests has focused on the factors that influence the intensity and outcome of aggressive contests
within nonsocial species, while relatively little is known about contests in social taxa. Here, we examine contests among
queens of the social paper wasp, Polistes dominulus. Queens use multiple reproductive strategies, including nesting alone, usurping established colonies, and cooperatively joining
other queens. We stage contests between a nesting queen and a challenger to test how resource value (RV) and resource holding
potential (RHP) influence (a) who occupies the nest at the end of the contest and (b) the extent of conflict between the queen
and challenger. We found that RHP, as measured by individuals’ facial patterns and body size, influenced the outcome of the
contest. Challengers with high RHP were more likely to successfully usurp the nest than challengers with low RHP. Interestingly,
queens with relatively high RHP were more likely to form a cooperative association with the challenger than queens with lower
RHP, suggesting that queens may evict individuals that are an aggressive threat. RV influenced the intensity of conflict.
There was more aggressive conflict over large nests than over small nests. Overall, social taxa have complex contest dynamics
with important parallels to contests in nonsocial taxa. Studying contests in social taxa provides an important perspective
on the factors that influence individual decisions about conflict versus cooperation. 相似文献
58.
59.
孔繁德 《中国环境管理干部学院学报》2003,13(2):14-16
中荷水处理示范研究培训中心是中荷合作的产物,今后将对中国各城市污水处理技术人员、高校师生等进行培训,为建设和管理污水处理厂提供技术咨询,开展污水处理新技术的开发与推广,并开展对内对外的合作与交流。 相似文献
60.
为研究"一带一路"国际合作高峰论坛在京召开期间北京市典型城区环境空气中挥发性有机物(VOCs)的污染特征及有毒有害VOCs的健康风险,本研究于2017年5月1—17日,在北京市典型城区利用Airmo VOC在线分析仪进行了观测研究.结果表明,整个观测期间总VOCs质量浓度日均值为29.99μg·m~(-3);空气质量保障期间(5月6—15日),大气中VOCs的浓度低于未采取控制措施的其它阶段,沙尘阶段VOCs浓度由于受到风速和气团传输影响出现最低值;各类VOCs的质量浓度在交通早高峰出现高值.PMF来源解析表明,移动源尾气排放(37.62%)、溶剂使用源(33.25%)、油气挥发源(16.39%)和天然气燃烧源(12.74%)的排放是北京市"一带一路"会议期间环境空气中VOCs的主要来源.化学活性分析表明,芳香烃和烯烃对臭氧生成潜势贡献的占比最多,需要重点控制的VOCs物种为间对二甲苯、甲苯和丙烯.健康风险评价结果表明,研究区整个观测期间及各阶段的苯和1,2-二氯乙烷均存在潜在的致癌风险,14种有毒有害VOCs(包括苯和1,2-二氯乙烷)不存在非致癌风险. 相似文献