全文获取类型
收费全文 | 508篇 |
免费 | 4篇 |
国内免费 | 11篇 |
专业分类
安全科学 | 9篇 |
废物处理 | 53篇 |
环保管理 | 28篇 |
综合类 | 55篇 |
基础理论 | 104篇 |
污染及防治 | 197篇 |
评价与监测 | 55篇 |
社会与环境 | 22篇 |
出版年
2023年 | 9篇 |
2022年 | 24篇 |
2021年 | 28篇 |
2020年 | 13篇 |
2019年 | 6篇 |
2018年 | 18篇 |
2017年 | 22篇 |
2016年 | 43篇 |
2015年 | 18篇 |
2014年 | 42篇 |
2013年 | 46篇 |
2012年 | 31篇 |
2011年 | 46篇 |
2010年 | 22篇 |
2009年 | 20篇 |
2008年 | 24篇 |
2007年 | 33篇 |
2006年 | 18篇 |
2005年 | 9篇 |
2004年 | 19篇 |
2003年 | 6篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1983年 | 1篇 |
排序方式: 共有523条查询结果,搜索用时 362 毫秒
491.
Carvalho LR Vasconcellos PC Mantovani W Pool CS Pisani SO 《Journal of environmental monitoring : JEM》2005,7(5):493-499
This study is part of a three-year project on biogenic volatile organic compound (VOC) emissions from trees of the temperate warm Atlantic rainforest found in the metropolitan area of Sao Paulo City (MASP). No study of VOC emission rates from plant species has been carried out in the temperate warm Atlantic rainforest of Brazil prior to this work. Eleven species were selected (Alchornea sidifolia, Cupania oblongifolia, Cecropia pachystachia, Syagrus romanzoffiana, Casearia sylvestris, Machaerium villosum, Trema micrantha, Croton floribundus, Myrcia rostrata, Solanum erianthum and Ficus insipida) and some of them were studied in urban, sub-urban and forest areas inside the MASP in order to evaluate biogenic VOC composition at sites characterized by different emission sources. Biogenic VOC emissions were determined by placing branches of plants in a dynamic enclosure system, an all-Teflon cuvette, and by sampling the compounds in the air leaving the cuvette. Pre-concentration using adsorbents to retain the VOC, followed by GC-MS after thermal desorption of the sample, was employed to determine the amount of biogenic hydrocarbons. The collection of carbonyl compounds on a 2,4-dinitrophenylhydrazine coated silica followed by HPLC-UV was used to analyze low molecular weight carbonyl compounds. Emission rates of isoprene, alpha-pinene, camphene and limonene ranged from 0.01 to 2.16 microg C h(-1) g(-1) and emission rates of aldehydes (C(2)-C(6)), acrolein, methacrolein and 2-butanone ranged from 1.5 x 10(-2) to 2.3 micro g C h(-1) g (-1). Ambient and leaf temperatures, relative humidity, light intensity, O(3) and NO(x) levels in the local atmosphere were monitored during experiments. It was possible to identify different biogenic VOCs emitted from typical plants of temperate warm Atlantic rainforest. The emission rates were reported as a function of the type of site investigated and were only provided for compounds for which quantification was feasible. Other biogenic compounds were only identified. 相似文献
492.
The response of Pinus maximartinezii Rzedowski to photochemical oxidant air pollution was examined using 100 trees, during a 1 year cycle, at Vivero de Coyoacán, a tree nursery located in the south central part of México City, where exposure to polluted air masses has been continuous. The tree response assessment method was based upon documented symptoms of pollutant injury on the foliage. The results showed a homogeneous pattern of health and vigor and only medium sensitivity (based on foliar injury) to photochemical oxidants, although the trees maintained their needles through a three and not the normal 5 year period as at its geographic location of origin (different habitat or environment). Nevertheless, these data suggest that this species of pine could be proposed as good planting material for reforestation in the urban metropolitan area of México city. 相似文献
493.
Mapping and Modeling the Biogeochemical Cycling of Turf Grasses in the United States 总被引:6,自引:0,他引:6
Milesi C Running SW Elvidge CD Dietz JB Tuttle BT Nemani RR 《Environmental management》2005,36(3):426-438
Turf grasses are ubiquitous in the urban landscape of the United States and are often associated with various types of environmental
impacts, especially on water resources, yet there have been limited efforts to quantify their total surface and ecosystem
functioning, such as their total impact on the continental water budget and potential net ecosystem exchange (NEE). In this
study, relating turf grass area to an estimate of fractional impervious surface area, it was calculated that potentially 163,800
km2 (± 35,850 km2) of land are cultivated with turf grasses in the continental United States, an area three times larger than that of any irrigated
crop. Using the Biome-BGC ecosystem process model, the growth of warm-season and cool-season turf grasses was modeled at a
number of sites across the 48 conterminous states under different management scenarios, simulating potential carbon and water
fluxes as if the entire turf surface was to be managed like a well-maintained lawn. The results indicate that well-watered
and fertilized turf grasses act as a carbon sink. The potential NEE that could derive from the total surface potentially under
turf (up to 17 Tg C/yr with the simulated scenarios) would require up to 695 to 900 liters of water per person per day, depending
on the modeled water irrigation practices, suggesting that outdoor water conservation practices such as xeriscaping and irrigation
with recycled waste-water may need to be extended as many municipalities continue to face increasing pressures on freshwater. 相似文献
494.
495.
Marguerite Miguet Julien Thevenon Vincent Laugel Mathilde Lefebvre Aurélie Bourchany Jean-Baptiste Rivière Yannis Duffourd Elise Schaefer Maria Cristina Antal Rosalie Abida Anne-Sophie Weingertner Valérie Kremer Pierre Vabres Fanny Morice-Picard Marie Gonzales Dan Lipsker Sylvie Fraitag Jean-Louis Mandel Jamel Chelly Hélène Dollfus Laurence Faivre Christel Thauvin-Robinet Nadège Calmels Salima El Chehadeh 《黑龙江环境通报》2016,36(13):1276-1279
496.
Dielle Monteiro Teixeira Juliana Merces Hernandez Luciana Damascena Silva Darleise de Souza Oliveira Paula Katharine de Pontes Spada Tereza Cristina Monteiro Gurjão Joana D’Arc Pereira Mascarenhas Alexandre Costa Linhares Lena Líllian Canto de Sá Morais Yvone Benchimol Gabbay 《Food and environmental virology》2016,8(1):101-104
Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil. 相似文献
497.
Chingoileima Maibam Patrick Fink Giovanna Romano Maria Cristina Buia Maria Cristina Gambi Maria Beatrice Scipione Francesco Paolo Patti Maurizio Lorenti Emanuela Butera Valerio Zupo 《Marine Biology》2014,161(7):1639-1652
Plants evolve the production of wound-activated compounds (WACs) to reduce grazing pressure. In addition, several plant-produced WACs are recognized by various invertebrates, playing the role of infochemicals. Due to co-evolutionary processes, some invertebrates recognize plant infochemicals and use them to identify possible prey, detect the presence of predators or identify algae containing various classes of toxic metabolites. Different metabolites present in the same algae can play the role of toxins, infochemicals or both simultaneously. We investigated the infochemical activity of compounds extracted from three diatoms epiphytes of the seagrass Posidonia oceanica, by conducting choice experiments on invertebrates living in the same community or in close proximity. Furthermore, the specific toxicity of the extracts obtained from the same algae was tested on sea urchin embryos using a standard bioassay procedure, to detect the presence of toxins. The comparison of the two effects demonstrated that invertebrates are subjected to diatom wound-activated toxicants when these algae are not associated with their own habitat, but they are able to recognize volatile infochemicals derived from diatoms associated with their habitats. The specific toxicity of WACs was shown to be inversely correlated to the perceptive ability of invertebrates towards volatile compounds liberated by the same algae. Hence, when the recognition of specific algae by a given invertebrate species evolves, their detrimental effects on the receiving organism may be lost. 相似文献
498.
499.
The likely introduction of non-indigenous species into the coastal ecosystems of oceanic islands through live-bait utilizations was studied. A store survey identified the species that are traded as live fishing-bait. Only Polychaeta species were identified as imported live-bait on São Miguel Island and all specimens were identified as Perinereis linea. Reponses to surveys of 77 anglers showed that: 44 % harvest from native sources, 44 % buy live-bait and 12 % do both; 56 % of the anglers’ fish on a weekly basis; 31 % dispose of the bait into the sea. A field survey at five sites where fishing rods are routinely utilized was developed to investigate if the non-indigenous polychaetes sold as fishing-bait are already established in the natural environment of the Azores archipelago. Three species of Nereididae were identified: the native Neanthes nubila and P. oliveirae and the cryptogenic P. cultrifera. The escalating utilization of live-bait argues for a change in the habits of fishermen with respect to the discarding of leftover bait, as the higher the volume of discards the higher becomes the probability of non-indigenous species establishment successes, especially on oceanic islands characterized by vulnerable ecosystems with simpler trophic webs. 相似文献
500.
Raymond V. Barbehenn Julie Niewiadomski Cristina Pecci Juha-Pekka Salminen 《Chemoecology》2013,23(1):59-70
The rapid growth of insects that feed on tree leaves in the spring is believed to be due to high nutritional quality. This study tested the hypothesis that both high nutritional quality and low levels of oxidative stress (i.e., toxicological effects) benefit caterpillars that feed in the spring. Fourth-instar larvae of Lymantria dispar (Lepidoptera: Lymantriidae) were used to bioassay the leaves of two contrasting host plants in the spring and summer: red oak (Quercus rubra), a high-quality host, and sugar maple (Acer saccharum), a low-quality host. On spring foliage, the combined effects of rapid consumption rate, efficient nutrient assimilation, and high nutritional quality allowed larvae to grow rapidly and attain larger body mass. Ellagitannins, a major source of oxidative stress in the midgut, were at higher concentrations in the spring than in the summer in maple leaves, but were at negligible levels throughout the growing season in oak. Thus, the impact of phenolic defenses (measured as semiquinone free radicals and oxidized glutathione in the midgut) was not decreased in spring-feeding larvae. Instead, oxidative stress in larvae on maple remained at elevated levels in the spring and summer. By contrast, larvae that fed on oak had consistently low levels of oxidative stress. We conclude that oak and maple were better host plants in the spring because of their higher nutritional quality, and not because of a lower effectiveness of their chemical defenses. This work emphasizes the need to measure not only foliar nutritional and phenolic chemistry but also specific physiological responses in the herbivore, such as oxidative stress. These physiological mechanisms add to our understanding of why spring-feeding life-history strategies have evolved in some insect herbivores. 相似文献