全文获取类型
收费全文 | 475篇 |
免费 | 12篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 17篇 |
废物处理 | 9篇 |
环保管理 | 92篇 |
综合类 | 49篇 |
基础理论 | 118篇 |
污染及防治 | 137篇 |
评价与监测 | 22篇 |
社会与环境 | 38篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 12篇 |
2017年 | 14篇 |
2016年 | 15篇 |
2015年 | 9篇 |
2014年 | 10篇 |
2013年 | 35篇 |
2012年 | 23篇 |
2011年 | 35篇 |
2010年 | 18篇 |
2009年 | 34篇 |
2008年 | 25篇 |
2007年 | 31篇 |
2006年 | 32篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 19篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 7篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 3篇 |
1984年 | 4篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有490条查询结果,搜索用时 31 毫秒
71.
Ben Vanpeperstraete Sébastien Duyck Medani P. Bhandari Janis Brizga Leida Rijnhout Sylvia Lorek A. Peter Castro Chiung Ting Chang Herman Daly Robert J. Didham Gianluca Ferraro Oliver Greenfield Ashok Khosla Ernst Ulrich von Weizsäcker Birgit Lode Simon Miles Henrique Pacini Semida Silveira Leisa Perch Jaap Rijnsburger Mukul Sanwal Sameera Savarala S. Jacob Scherr Kallidaikurichi E. Seetharam A.M.M. Adeeb Donna Shepherd Adrian Smith Lisinka Ulatowska Alice Vincent Werner John 《Natural resources forum》2011,35(4):334-342
72.
Personality, individual differences, and demographic antecedents of self-reported household waste management behaviours 总被引:1,自引:0,他引:1
Viren Swami Tomas Chamorro-PremuzicRosemary Snelgar Adrian Furnham 《Journal of environmental psychology》2011,31(1):21-26
The present study sought to extend recent conceptual frameworks of waste management behaviours by examining personality, individual differences, and socio-demographic antecedents of self-reported waste recycling, reuse, and reduction behaviours. A total of 203 participants from a British community sample completed a questionnaire consisting of measures of their self-reported waste management behaviour, Machiavellianism, political cynicism, the Big Five personality traits, and socio-demographics. The results of structural equation modelling showed that individuals who were less Machiavellian, less politically cynical, older, and more conscientious were more likely to report positive waste management behaviours. In combination, these predictors explained 22.0% of the variance in waste management behaviours. Thus, these variables may improve the predictive validity of existing conceptual models of waste management behaviours. The results are discussed in relation to those models. 相似文献
73.
Stakeholder Opinions on the Assessment of MPA Effectiveness and Their Interests to Participate at Pacific Rim National Park Reserve,Canada 总被引:1,自引:1,他引:0
As the number of marine protected areas (MPAs) is globally increasing, information is needed on the effectiveness of existing
sites. Many protected area agencies however have limited resources and are unable to evaluate MPA effectiveness. An evaluation
conducted entirely by the managing agency may also lack credibility. Long-term monitoring and evaluation programs should ideally
offer opportunities for participation of diverse groups in the selection of evaluation indicators and their assessment. A
participatory approach has the potential to enhance evaluation capacity, to increase credibility and acceptance of results,
to strengthen relationships between managers and local stakeholders, and to address more locally relevant information. Using
a case study approach, this paper investigates diverse stakeholder groups’ opinions on the design of an evaluation and their
interest to participate in an assessment. Respondents were most interested in the assessment of MPA achievements and outcome
indicators. Most groups identified a range of government agencies and stakeholders that should participate in an assessment
but only half of all respondents were interested to participate in monitoring activities. Most frequently mentioned limitations
for more participation were a lack of time and money, but also governance shortcomings such as limited participation possibilities
and not paying enough credit to stakeholders’ input. Participation interest was also influenced by occupation, place of residency,
and familiarity with the marine environment. Differences exist among stakeholders about suitable evaluators and preferred
monitoring partners, which could affect the credibility of evaluation results and affect monitoring activities. 相似文献
74.
David L. Clark J. Andrew Roberts Meghan Rector George W. Uetz 《Behavioral ecology and sociobiology》2011,65(6):1237-1247
Animal color patterns often reflect a compromise between natural selection for crypsis or inconspicuousness to predators and
sexual selection for conspicuousness to potential mates. In leaf litter-dwelling wolf spider species like Schizocosa ocreata, body coloration often closely matches the background coloration of a generally brown environment. However, body parts used
in communication should exhibit high contrast against background coloration. We used spectral analysis to examine male and
female S. ocreata for matching and contrasting coloration against leaf litter. Values were plotted in multivariate color space, based on reflectivity
in different frequency ranges. When viewed from above, colors of both males and females overlap with values for dead brown
leaf litter and soil, suggesting cryptic coloration when viewed by potential predators. However, when viewed from a lateral
perspective, both males and females show color values that are polar opposites of litter backgrounds, suggesting higher contrast
when viewed by other spiders. Moreover, male secondary characters used in visual signaling by S. ocreata (tibia brushes) show the highest level of background contrast. These findings suggest that S. ocreata wolf spiders have color patterns that provide both crypsis and background contrast at the same time, depending on receiver
viewing perspective. 相似文献
75.
Spatial elements of mortality risk in old-growth forests 总被引:3,自引:0,他引:3
For many species of long-lived organisms, such as trees, survival appears to be the most critical vital rate affecting population persistence. However, methods commonly used to quantify tree death, such as relating tree mortality risk solely to diameter growth, almost certainly do not account for important spatial processes. Our goal in this study was to detect and, if present, to quantify the relevance of such processes. For this purpose, we examined purely spatial aspects of mortality for four species, Abies concolor, Abies magnifica, Calocedrus decurrens, and Pinus lambertiana, in an old-growth conifer forest in the Sierra Nevada of California, USA. The analysis was performed using data from nine fully mapped long-term monitoring plots. In three cases, the results unequivocally supported the inclusion of spatial information in models used to predict mortality. For Abies concolor, our results suggested that growth rate may not always adequately capture increased mortality risk due to competition. We also found evidence of a facilitative effect for this species, with mortality risk decreasing with proximity to conspecific neighbors. For Pinus lambertiana, mortality risk increased with density of conspecific neighbors, in keeping with a mechanism of increased pathogen or insect pressure (i.e., a Janzen-Connell type effect). Finally, we found that models estimating risk of being crushed were strongly improved by the inclusion of a simple index of spatial proximity. Not only did spatial indices improve models, those improvements were relevant for mortality prediction. For P. lambertiana, spatial factors were important for estimation of mortality risk regardless of growth rate. For A. concolor, although most of the population fell within spatial conditions in which mortality risk was well described by growth, trees that died occurred outside those conditions in a disproportionate fashion. Furthermore, as stands of A. concolor become increasingly dense, such spatial factors are likely to become increasingly important. In general, models that fail to account for spatial pattern are at risk of failure as conditions change. 相似文献
76.
Judith A. Zbinden Adrian Aebischer Dimitris Margaritoulis Raphaël Arlettaz 《Marine Biology》2008,153(5):899-906
Sea turtle populations worldwide suffer from reduced survival of immatures and adults due to fishery bycatch. Unfortunately,
information about the whereabouts of turtles outside the breeding habitat is scarce in most areas, hampering the development
of spatially explicit conservation plans. In the Mediterranean, recoveries of adult females flipper-tagged on nesting beaches
suggest that the Adriatic Sea and Gulf of Gabès are important foraging areas for adults, but such information could be heavily
biased (observing and reporting bias). In order to obtain unbiased data, we satellite-tracked seven loggerhead sea turtles
after they completed nesting in the largest known Mediterranean rookery (Bay of Laganas, Zakynthos, Greece). Three females
settled in the north Adriatic Sea, one in the south Adriatic Sea and two in the Gulf of Gabès area at the completion of their
post-nesting migrations (one individual did not occupy a distinct foraging area). The concordance of tracking results with
information from recoveries of flipper-tagged turtles suggests that the north Adriatic Sea and the Gulf of Gabès represent
key areas for female adult Mediterranean loggerhead sea turtles. 相似文献
77.
Love bites: male fang use during coercive mating in wolf spiders 总被引:1,自引:1,他引:0
Julianna L. Johns J. Andrew Roberts David L. Clark George W. Uetz 《Behavioral ecology and sociobiology》2009,64(1):13-18
Evolutionary conflicts of interest between the sexes are common, as mating tactics and strategies that increase fitness benefits
for one sex may incur costs for the other. As a consequence, antagonistic coevolution between the sexes often results in a
complex arms race between male persistence and female resistance. Coercive mating (e.g., forced copulation) likely benefits
males by increasing the probability of mating; however, costs to females may be high, including injury or even death. Here,
we report on a study of the use of fangs by males of the wolf spider Schizocosa ocreata (Hentz) during forcible mating with resistant females, which results in hemolymph loss and scar tissue formation in females.
Microscopic inspection revealed that fang wounds (evidenced by scar tissue) were absent on unmated (virgin) females but were
found on mated females and were significantly more frequent in coercively mated females. Experimental fang immobilization
studies found no difference in copulation success between experimental (fangs immobilized) and control (sham manipulation)
males. However, males that had use of their fangs had significantly longer copulation duration. These findings represent a
previously unknown male mating tactic in spiders and an unrecognized potential cost of mating for female spiders. 相似文献
78.
Christer Wiklund Adrian Vallin Magne Friberg Sven Jakobsson 《Behavioral ecology and sociobiology》2008,62(3):379-389
Insects that hibernate as adults have a life span of almost a whole year. Hence, they must have extraordinary adaptations
for adult survival. In this paper, we study winter survival in two butterflies that hibernate as adults and have multimodal
anti-predator defences—the peacock, Inachis io, which has intimidating eyespots that are effective against bird predation, and the small tortoiseshell, Aglais urticae, which does not have an effective secondary defence against birds. We assessed predation on wild butterflies hibernating
in the attic of an unheated house, as well as survival of individually marked butterflies placed by hand on different sites
in the attic. Our objectives were to assess (1) the number of butterflies that were killed during hibernation, (2) whether
survival differed between butterfly species, and (3) how predation was related to hibernation site and the identity of the
predator. There was a strong pulse of predation during the first 2 weeks of hibernation: 58% of A. urticae and 53% of I. io were killed during this period. Thereafter, predation decreased and butterfly survival equalled 98% during the final 16 weeks
of hibernation. There was no difference in survival between the two butterfly species, but predation was site-specific and
more pronounced under light conditions in locations accessible to a climbing rodent, such as the common yellow-necked mouse,
Apodemus flavicollis. We contend that small rodents are likely important predators on overwintering butterflies, both because rodents are active
throughout winter when butterflies are torpid and because they occur at similar sites. 相似文献
79.
Prudence Jarrett Frank J. Zadravecz Jennifer O'Keefe Marius Nshombo Augustin Karume Les Roberts 《Disasters》2020,44(2):390-407
Prospective, community-based surveillance systems for measuring birth, death, and population movement rates may have advantages over the ‘gold-standard’ retrospective household survey in humanitarian contexts. A community-based, monthly surveillance system was established in South Kivu, Democratic Republic of the Congo, in partnership with a local implementing partner and the national ministry of health. Data were collected on the occurrence of births, deaths, arrivals, and departures over the course of one year, and a retrospective survey was conducted at the end of the period to validate the information. Discrepancies between the two approaches were resolved by a third visit to the households with discordant records. The study found that the surveillance system was superior in terms of its specificity and sensitivity in measuring crude mortality and birth rates as compared to the survey, demonstrating the method's potential to measure accurately important population-level health metrics in an insecure setting in a timely, community-acceptable manner. 相似文献
80.
Alan E. Wilson Michael F. Chislock Zhen Yang Mário U. G. Barros John F. Roberts 《Environmental monitoring and assessment》2018,190(4):247
Forty-one livestock drinking water ponds in Alabama beef cattle pastures during were surveyed during the late summer to generally understand water quality patterns in these important water resources. Since livestock drinking water ponds are prone to excess nutrients that typically lead to eutrophication, which can promote blooms of toxigenic phytoplankton such as cyanobacteria, we also assessed the threat of exposure to the hepatotoxin, microcystin. Eighty percent of the ponds studied contained measurable microcystin, while three of these ponds had concentrations above human drinking water thresholds set by the US Environmental Protection Agency (i.e., 0.3 μg/L). Water quality patterns in the livestock drinking water ponds contrasted sharply with patterns typically observed for temperate freshwater lakes and reservoirs. Namely, we found several non-linear relationships between phytoplankton abundance (measured as chlorophyll) and nutrients or total suspended solids. Livestock had direct access to all the study ponds. Consequently, the proportion of inorganic suspended solids (e.g., sediment) increased with higher concentrations of total suspended solids, which underlies these patterns. Unimodal relationships were also observed between microcystin and phytoplankton abundance or nutrients. Euglenoids were abundant in the four ponds with chlorophyll concentrations >?250 μg/L (and dominated three of these ponds), which could explain why ponds with high chlorophyll concentrations would have low microcystin concentrations. Based on observations made during sampling events and available water quality data, livestock-mediated bioturbation is causing elevated total suspended solids that lead to reduced phytoplankton abundance and microcystin despite high concentrations of nutrients, such as phosphorus and nitrogen. Thus, livestock could be used to manage algal blooms, including toxic secondary metabolites, in their drinking water ponds by allowing them to walk in the ponds to increase turbidity. 相似文献