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121.
湖南省蚂蚁区系研究   总被引:4,自引:0,他引:4  
本文对湖南73种蚂蚁进行了区系研究.结果表明:湖南蚂蚁区系以东洋成分为主体,其次为东洋与古北共有成分.  相似文献   
122.
根据1990~1991年调查,鳡鱼河现有鱼类39种和亚种,分别隶属于3目8科32属。其中新记录7种,在鱼类区系成份中鲤科占绝对优势,鳅科占第2位,其地理分布表现出四川东、西部鱼类过渡性特点,鳡鱼河鱼类资源破坏严重,亟待加强保护。  相似文献   
123.
ABSTRACT: Studies on the responses of zooplankton to dredging are summarized and discussed. Design criteria for studies intended for impact assessment require careful consideration of sampling due to the highly variable spatial and temporal distributions of zooplankton. It is suggested that ocean dominated systems present different research requirements than those estuarine regions which have endemic zooplankton populations.  相似文献   
124.
• Earthworms increase CO2 and N2O emissions in agricultural and forest soil. • 10% biochar suppresses CO2 and N2O emissions in forest soil. • Biochar interacted with earthworm to significant affect CO2 and N2O emissions. The application of manure-derived biochar offers an alternative to avoid the direct application of manure to soil causing greenhouse gas emission. Soil fauna, especially earthworms, can markedly stimulate carbon dioxide (CO2) and nitrous oxide (N2O) emissions from soil. This study therefore investigated the effect of cattle manure biochar (added at rates of 0, 2%, or 10%, coded as BC0, BC2 and BC10, respectively) application, with or without earthworm Aporrectodea turgida, on emissions of CO2 and N2O and changes of physic-chemical properties of agricultural and forest soils in a laboratory incubation experiment. The BC10 treatment significantly enhanced cumulative CO2 emissions by 27.9% relative to the untreated control in the agricultural soil. On the contrary, the BC2 and BC10 treatments significantly reduced cumulative CO2 emissions by 16.3%–61.1% and N2O emissions by 92.9%–95.1% compared to the untreated control in the forest soil. The addition of earthworm alone significantly enhanced the cumulative CO2 and N2O fluxes in agricultural and forest soils. Cumulative CO2 and N2O fluxes were significantly increased when BC2 and BC10 were applied with earthworm in the agricultural soil, but were significantly reduced when BC10 was applied with earthworm in the forest soil. Our study demonstrated that biochar application interacted with earthworm to affect CO2 and N2O emissions, which were also dependent on the soil type involved. Our study suggests that manure biochar application rate and use of earthworm need to be carefully studied for specific soil types to maximize the climate change mitigation potential of such management practices.  相似文献   
125.
There is a lack of quantitative information on the effectiveness of selective‐logging practices in ameliorating effects of logging on faunal communities. We conducted a large‐scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest‐dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance‐tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance‐tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low‐intensity logging (≤3 trees/ha) a minimum 20‐year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. Recuperación de Ensambles de Anfibios en Dos Etapas Después de la Tala Selectiva de Bosques Tropicales  相似文献   
126.
/ The coastal environment of Kuwait has been under considerable stress since the onset of the oil era in the late 1950s and early 1960s. Oil, sewage, and industrial pollution were believed to be the main environmental problems in the coastal zone. The huge oil spill and destruction caused by the Gulf War further complicated those problems. In this article, the temperature, pH, salinity, and total dissolved sulfide (TDS) of the interstitial water in the intertidal zone and the water content and total organic carbon (TOC) of the intertidal sediment were investigated. The purpose of the study was to understand the effect of the physicochemical characteristics on the intertidal benthic ecology and to identify the level and sources of organic pollution in the intertidal zone. The study results indicated that the prevailing harsh environmental conditions, especially high temperature and salinity, restricted benthic fauna diversity and led to the development of a fragile intertidal ecosystem. The fauna inhabiting the intertidal zone was dominated by a few species probably living at their limit of tolerance. Organic pollution was evident mainly in Sulaibikhat Bay and to a lesser extent in Kuwait City waterfront and Shuaiba coast in the south. The pollution was attributed mainly to land-based sources such as the occasional discharge of raw sewage through stormwater outlets, the direct oil spillage, and industrial effluents from refineries, oil terminals, and petrochemical plants. Quantitative analysis was inconclusive in establishing a significant correlation between the chemistry and composition of the benthic fauna. However, close examination of sites with high TOC and TDS concentrations indicated that the benthic fauna in those sites was showing evidence of degradation. A number of strategies were recommended to ensure protection and sustainable management of the coastal environment.KEY WORDS: Intertidal environment; Pollution; Total organic carbon; Dissolved sulfide; Interstitial water; Benthic fauna  相似文献   
127.
The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future.  相似文献   
128.
Unsustainable exploitation of wild species represents a serious threat to biodiversity and to the livelihoods of local communities and Indigenous peoples. However, managed, sustainable use has the potential to forestall extinctions, aid recovery, and meet human needs. We analyzed species-level data for 30,923 species from 13 taxonomic groups on the International Union for Conservation of Nature Red List of Threatened Species to investigate patterns of intentional biological resource use. Forty percent of species (10,098 of 25,009 species from 10 data-sufficient taxonomic groups) were used. The main purposes of use were pets, display animals, horticulture, and human consumption. Intentional use is currently contributing to elevated extinction risk for 28–29% of threatened or near threatened (NT) species (2752–2848 of 9753 species). Intentional use also affected 16% of all species used (1597–1631 of 10,098). However, 72% of used species (7291 of 10,098) were least concern, of which nearly half (3469) also had stable or improving population trends. The remainder were not documented as threatened by biological resource use, including at least 172 threatened or NT species with stable or improving populations. About one-third of species that had use documented as a threat had no targeted species management actions to directly address this threat. To improve use-related red-list data, we suggest small amendments to the relevant classification schemes and required supporting documentation. Our findings on the prevalence of sustainable and unsustainable use, and variation across taxa, can inform international policy making, including the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, the Convention on Biological Diversity, and the Convention on International Trade in Endangered Species.  相似文献   
129.
为了解采伐干扰对巨桉人工林土壤动物的影响,采用手捡法和干湿漏斗法对四川省洪雅县巨桉人工林采伐干扰前和干扰后土壤动物群落进行调查.结果显示:巨桉人工林采伐干扰前后共获大中小型土壤动物5 578头,分属4门10纲25目,采伐干扰后共减少1 290头,类群数减少了3个.采伐干扰前后中小型湿生、干生土壤动物剖面分布具有明显的表聚性,均与地温呈负相关,与土壤有机质含量和土壤含水量呈正相关.采伐干扰对各层中小型湿生、干生土壤动物个体数均有极显著影响(P<0.01),并导致Shannon-Wiener(H′)多样性指数和Pielou(J)均匀性指数增加,密度-类群指数(DG)减小,Simpson(C)优势度指数无显著变化,表明采伐干扰对巨桉人工林土壤动物群落结构有较大影响.  相似文献   
130.
Reducing costs and increasing benefits for rural communities coexisting with large carnivores is necessary for conservation of jaguar (Panthera onca) and puma (Puma concolor). To design acceptable incentives, stakeholders must be involved in the process. We conducted an innovative, structured, group communication process based on a Delphi technique as a template for identifying potential incentives. Community workshops with 133 members of 7 communities and surveys with 25 multidisciplinary experts from government, nongovernmental organizations, and academia provided iterative data to design a plan of incentives through 4 rounds of discussion. The final product integrated 862 ideas into 6 types of incentives: organization of communities, mechanisms for improved dialogue, citizen technical assistance, green labeling for community products, payment for the ecosystem service of biodiversity, and an assessment of financial alternatives. We used quantitative and qualitative techniques to indicate support for decisions about the design of incentives, which reduced researcher subjectivity. The diverse incentives developed and the cooperation from multiple stakeholders resulted in an incentive plan that integrated issues of governance, equity, and social norms.  相似文献   
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