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61.
环保执法是政府环境保护行政主管部门对环境保护工作统一监督管理的主要抓手之一,是实现环境质量根本好转的重要手段,文章从环保法律体系、环保法制建设、政府环境管理体制、市区两级环保部门执法现状等方面,分析了上海市环保执法的现状及存在的问题。从完善环境保护法律法规、强化经济手段、解决环保执法监督机制和工作机制,实行执法效能评估、健全环保执法监督制约机制等方面,提出了建设性的对策建议。 相似文献
62.
D. Kline L. Vimmerstedt R. Benioff 《Mitigation and Adaptation Strategies for Global Change》2004,9(1):1-35
This paper describes the experience andresults of programs designed tooperationalize the technology transferprovisions of the United Nations FrameworkConvention on Climate Change (UNFCCC). These programs share a common goal ofdemonstrating modalities for developedcountry parties to fulfill their obligationunder the UNFCCC to supporttechnology transfer to developing countryparties that facilitates theirparticipation in global efforts to combatclimate changes. Several related U.S.bilateral programs and programs supportedby the Climate Technology Initiative, amultilateral effort on behalf of a numberof Organization for Economic Cooperation and Development (OECD) countries, are included in thisreview. The discussion highlights a numberof common elements of the approaches ofmany of these programs as well as somedifferences. It presents case studies thatfocus on methods and results in China,Mexico, and Southern Africa, and cataloguesand describes the implementation activitiesand results that these programs haveachieved. It concludes by assessing theimplications of this experience for theinternational community as it moves forwardwith the climate change technology transferenterprise. 相似文献
63.
Aviva E. Liebert Peter Nonacs Robert K. Wayne 《Behavioral ecology and sociobiology》2005,57(5):445-456
Female Polistes paper wasps are capable of independent nesting, yet many populations demonstrate a mixture of solitary and cooperative nest foundation. Previous studies of Polistes have found survival and/or productivity advantages of cooperative nest foundation compared to solitary nesting, and reproductive skew models have been designed to predict the dynamics of such flexible cooperation. In this paper, we examine the success of different nesting strategies in a previously unstudied population of Polistes aurifer in southern California. The colony cycle of this population is less synchronous than that of other temperate species, and the frequency of solitary nesting averages 86.2%. Our data suggest that this low rate of cooperative nest founding is adaptive, as demonstrated by the lack of survival or productivity advantages for cooperative foundress associations. Due to foundress turnover and nest foundation later in the season, many nests produce only one set of offspring. This results in a loss of the eusocial nature of some nests in the population. Data from a small sample of multifoundress nests show significant positive reproductive skew, despite concession model predictions that skew should be low in populations with low ecological constraints on independent nesting. This lack of support for the concessions skew model reflects a diminished incentive for cooperation.Communicated by L. Keller 相似文献
64.
The process by which ant scouts move a group of nestmates toward a newly discovered food site is called recruitment. In this paper, I report on the interactions between scouts and nestmates that result in a graded recruitment response to graded food quality in the fire ant, Solenopsis invicta. Twelve experimental groups composed of 100 fire ant workers and 50 fire ant larvae were established (three experimental groups per colony × four stock colonies). Each experimental group was placed in a shallow, artificial nest with a glass cover. After a 48-h period of food deprivation, experimental groups were exposed to one of three concentrations of sugar water. Behavioral interactions between scouts and nestmates in each group were videotaped at 10× magnification for 20 min. Detailed behavioral data on a total of 120 scouts (10 scouts per experimental group) and ~1,000 nestmates (~90 nestmates per experimental group) were transcribed from the videotapes using standard play and frame-by-frame techniques. Throughout the recruitment process, scouts employed six discrete behaviors to inform nestmates of the location and quality of a food site. Scouts laid incoming trails, waggled their heads, increased walking tempo, stroked nestmates with their antennae, advertised with a brief food display, and led groups of nestmates to the food site by laying outgoing trails. In turn, nestmates assessed the food sample with antennae, then responded to or resisted recruitment based on the quality of food advertised, their employment status and their level of hunger. In summary, recruitment was an emergent property based on competent supply and demand decisions made face-to-face inside the nest rather than on the trail or at the food site.Communicated by J. Heinze 相似文献
65.
Walter R. Tschinkel 《Behavioral ecology and sociobiology》1998,43(4-5):247-257
Many benefits and risks of cooperative colony founding (pleometrosis) have been identified, but rarely have the proximate
factors that lead to association been considered. This study examined the choices queens make during the first few hours after
mating, and some of the correlates of those choices. Queens had a strong affinity for preformed holes in the soil and readily
used these as their initial founding chambers. This affinity was so strong that in a field experiment, the dispersion pattern
of preformed holes controlled the final dispersion of colony-founding queens. Attraction to partially formed holes is thus
an important cause of pleometrosis. The excavation of complete founding chambers incurred no measurable cost on the subsequent
reproductive output of queens, suggesting that the primary benefit of using preformed holes is to remove the queen quickly
from exposure to predation and desiccation. In the field, pairs of queens offered five equivalent preformed holes in soil
were more likely to share the same hole if the holes were shallow and close together. In these experiments, queens modified
preformed soil holes so that the test holes were no longer equivalent, causing the choice of queen and hole to become confounded.
Laboratory experiments in plaster arenas with unmodifiable holes confirmed the field experiments: queens were more likely
to share a hole when the holes were shallow than when they were deep. Because queens entering adequately deep holes seldom
reemerged, this suggested that the likelihood of sharing increased with increasing contact between queens, that is, when queens
were readily and frequently detected. Such contacts will also predict the future competitive environments to be experienced
by incipient colonies, and may temper the tendency of queens to associate. However, experiments in which queens were exposed
to high and low densities before pairing in the choice arenas failed to show an effect on the choice to join the resident
queen. Queens that joined a resident queen differed in their robustness from queens that did not join. Queens choosing their
own partners did no better reproductively than those assigned partners at random. Overall, this study suggests that (1) newly
mated queens are under strong selection to leave the soil surface and do so by using any available holes, whether dug by another
queen or of some other origin; (2) they are attracted to other queens, and are more likely to cofound as contact with the
potential cofoundress becomes more frequent and (3) they choose whether or not to cofound partly on the basis of their own
reproductive characteristics.
Received: 20 November 1997 / Accepted after revision: 14 March 1998 相似文献
66.
Stephen T. Trumbo 《Behavioral ecology and sociobiology》2007,61(11):1717-1723
A positive correlation between the parental effort of a male and female should promote stable biparental care. Risk-taking
(as assessed by injuries) against infanticidal intruders by Nicrophorus pustulatus females was expected to be low when females had a low probability of successful defense of the young. I tested the hypothesis
that when the presence of a male partner increased the probability of successful defense from low to moderate that female
risk-taking would increase. Single females and pairs with first instar larvae were confronted by potentially infanticidal
male and female conspecific intruders. Male intruders routinely took over nests from unpaired females (30 of 36 trials). Unpaired
females and male intruders were injured infrequently, indicating less intense fights despite the high probability of infanticide.
A resident female defending against a male intruder was injured more often when paired than unpaired, suggesting greater risk-taking.
A male parent that delays desertion, therefore, receives fitness benefits not only from his own defense of the young, but
from greater female defense against male intruders as well. It is hypothesized that the threat of infanticidal takeovers by
males promotes extended biparental care in burying beetles. When the intruder was female, on the other hand, a female parent
on her own had a moderate probability of successfully defending the brood (22 of 36 trials). The presence of a male partner
against female intruders almost guaranteed successful defense (35 of 36 trials) and female intruders did not appear to contest
pairs vigorously. Against female intruders the presence of a male partner did not significantly change injury rates of the
defending female. 相似文献
67.
Julie K. Desjardins Kelly A. Stiver John L. Fitzpatrick Nicole Milligan Glen J. Van Der Kraak Sigal Balshine 《Behavioral ecology and sociobiology》2008,62(5):785-794
Among taxonomically widespread cooperatively breeding vertebrates, those with non-breeding helpers-at-the-nest provide an
excellent opportunity to understand the proximate mechanisms underlying care and allocare. In this study, we examined androgen
levels in relation to care behavior in a cooperatively breeding cichlid fish, Neolamprologus pulcher, from Lake Tanganyika. We concentrated on androgens, as these hormones have been linked to the defense behavior, and the
defense of young is a common form of parental care in fishes. N. pulcher dominant female breeders performed the most care and also displayed the highest levels of plasma testosterone (T) compared
with other individuals within the social group. We also found that dominant male breeders provided a similar amount of care
as did the subordinate helpers, but breeding males had the highest levels of 11-ketotestosterone (11KT), an important androgen
in fish. Breeders had higher levels of both androgens (T and 11KT) compared to helpers. There was a weak but significant positive correlation between T levels and the frequency of
care regardless of sex and status. Our results suggest that androgens may promote defense of young and are in contrast to
the commonly reported trade-off between androgen and parental care. 相似文献
68.
Stefan M. Klose Justin A. Welbergen Anne W. Goldizen Elisabeth K. V. Kalko 《Behavioral ecology and sociobiology》2009,63(3):371-380
The social structure of animal aggregations may vary considerably in both space and time, yet little is known about how this
affects vigilance. Here, we investigate the vigilance architecture of a colony of wild-living grey-headed flying-foxes (Pteropus poliocephalus) in Australia and examine how spatial as well as temporal variation in social organization influences social and environmental
vigilance. We sampled color-marked individuals at different stages of the reproductive cycle and the year and at different
locations in the colony to examine the effects of temporal and spatial factors on social and environmental vigilance. We found
that vigilance architecture reflected the social structure of the colony, with the highest environmental vigilance being displayed
by bats at the periphery of the colony, and the highest social vigilance by bats that roosted at intermediate distances from
the colony’s edge. Furthermore, we found that vigilance levels reflected changes in reproductive state, with social vigilance
increasing toward the mating season, particularly in males. Our findings show that spatial and temporal variation in social
structure can have differential effects on social and environmental vigilance. This highlights the necessity to differentiate
between functions of vigilance to understand fully vigilance architecture in aggregations of social animals. 相似文献
69.
Lubell M 《Environmental management》2004,33(5):677-691
Since its beginning in 1987, researchers and policymakers have touted the US Environmental Protection Agency National Estuary program (NEP) as one of the leading examples of collaborative institutions designed to resolve conflict and build cooperation at the watershed level. Using the NEP as an example, I summarize the advantages and disadvantages of collaborative institutions. Using data gathered from focused surveys of policy elites in 22 estuaries, I estimate statistical models that show the NEP does a better job of resolving conflict and building project-level cooperation than similar estuaries without the NEP. I also describe the activities of the NEP mentioned by respondents as contributing to this outcome. 相似文献
70.
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