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111.
通过建立引入气候因素的种植业生产函数模型,利用1990-2009年山东省40个县市种植业生产及气象面板数据,运用产出增长分解法,实证分析气候因素和非气候因素对山东省种植业产出的影响并对产出增长的各要素贡献进行分解。结果表明:气候变暖对山东省种植业带来明显的负面影响。1990-2009年间气候因素对山东省40个县市的总体产出增长的影响为-11.03%,在其他条件不变的情况下,平均温度每升高1℃,总体种植业总产值减少2.2%,总体产值增长下降1.48%;温度升高对鲁西北地区、鲁南地区种植业产出的影响最为明显;同时,降水对种植业产出影响显著,降水因素使得山东省种植业产出增长减少16.86%;物质投入中化肥和农药对种植业产出增长贡献最大,但农业劳动力减少,特别是种植业劳动力的减少,开始显著地影响种植业产出,使得种植业产出增长减少5.90%;技术进步的影响作用在下降。 相似文献
112.
Lindahl P Maquet A Hult M Gasparro J Marissens G González de Orduña R 《Journal of environmental radioactivity》2011,102(2):163-169
The distribution of natural radionuclides was studied in winter wheat plants collected from three sites in Belgium during 2004-2007. Activity concentrations of 40K, 226Ra, 228Ra and 228Th in organically and conventionally grown wheat, and in the corresponding soil samples, were determined using ultra low-level gamma-ray spectrometry. The observed soil-to-wheat concentration ratios were calculated for the different parts of the wheat plant (root, stem and grain) in the two agricultural systems (organic and conventional). There were large variations in radionuclide activity concentrations between the sites and fields, but no significant difference between conventionally and organically grown wheat plants was observed. 相似文献
113.
Combination of multispectral remote sensing, variable rate technology and environmental modeling for citrus pest management 总被引:1,自引:0,他引:1
The Lower Rio Grande Valley (LRGV) of south Texas is an agriculturally rich area supporting intensive production of vegetables, fruits, grain sorghum, and cotton. Modern agricultural practices involve the combined use of irrigation with the application of large amounts of agrochemicals to maximize crop yields. Intensive agricultural activities in past decades might have caused potential contamination of soil, surface water, and groundwater due to leaching of pesticides in the vadose zone. In an effort to promote precision farming in citrus production, this paper aims at developing an airborne multispectral technique for identifying tree health problems in a citrus grove that can be combined with variable rate technology (VRT) for required pesticide application and environmental modeling for assessment of pollution prevention. An unsupervised linear unmixing method was applied to classify the image for the grove and quantify the symptom severity for appropriate infection control. The PRZM-3 model was used to estimate environmental impacts that contribute to nonpoint source pollution with and without the use of multispectral remote sensing and VRT. Research findings using site-specific environmental assessment clearly indicate that combination of remote sensing and VRT may result in benefit to the environment by reducing the nonpoint source pollution by 92.15%. Overall, this study demonstrates the potential of precision farming for citrus production in the nexus of industrial ecology and agricultural sustainability. 相似文献
114.
Frank W. Oudshoorn Reint Jan Renes Imke J. M. De Boer 《Journal of Agricultural and Environmental Ethics》2008,21(3):205-228
The aim of this study was to explore stakeholder perceptions of the contribution of an Automatic Milking System (AMS) to sustainable
development of organic dairy production in Denmark and the Netherlands. In addition, reasons for the current difference in
AMS use on organic dairy farms between both countries were explored. To answer above mentioned aims, farmers and advisors
in both countries were interviewed using a focus group approach. Questions of the interviews were based on a literature review
on sustainability issues affected by introduction of AMS. Participants expressed no moral problems regarding AMS use. They,
however, pointed out uncertainty about the economic gain, difficulties with grazing, adaptation problems to technology, and
image problems towards consumers. The latter results from a reduction in grazing time affecting both animal welfare and product
quality. The participants did not recognize eutrophication, as result of high stocking density on farmstead lots, as a problem
caused by AMS. The milk quality problem related to AMS use, although acknowledged as crucial towards consumers, was not prioritized
very highly, especially not by the farmers in both countries. All groups were, however, unanimous in their perception of how
important image was as far as the consumers are concerned. The perception analysis revealed that Dutch participants were more
concerned about the economic payoff of AMS use, and showed more reluctance towards enlargement than Danish ones. In addition,
they acknowledged the small-scale naturalness of organic production. These differences in perception could possibly explain
observed differences in AMS use in organic dairy production between Denmark and the Netherlands. 相似文献
115.
Abstract The vulnerable eco-area is one of the important research targets in the field of sustainable development. It is the requirement of building a well-off society in an all-round way that we should study more on the vulnerable eco-areas, deal with the relationship between environmental protection and economic development, speed up the economic development in these areas and increase the living standard of the local people. This paper puts forward the countermeasures of environment—economy coordination, on the basis of the recognition of eco- environment features and social economic conditions in the vulnerable eco-areas of China, in view of the progress in sustainable development studies of the vulnerable ones, taking the transitional areas of farming and pasturing in northeast China as an example to study the regional environment vulnerability. 相似文献
116.
Yali Liu Jianqing Du Boyang Ding Yuexian Liu Wenjun Liu Anquan Xia Ran Huo Qinwei Ran Yanbin Hao Xiaoyong Cui Yanfen Wang 《Frontiers of Environmental Science & Engineering》2022,16(3):28
117.
Bhavana Rao Kuchimanchi Imke J. M. De Boer Raimon Ripoll-Bosch Simon J. Oosting 《Ambio》2021,50(10):1809
Increasing food demands are causing rapid transitions in farming systems, often involving intensified land and resource use. While transitioning has benefits regarding poverty alleviation and food outputs, it also causes environmental and social issues over time. This study aims to understand the transitions in farming systems in a region in Telangana, from 1997 to 2015, and their effect on livestock rearing and smallholder livelihoods. We also examine the impact of the transitions on lower caste groups and women in particular. We collected data using a combination of methods, i.e., a household survey, focus group discussions, and secondary data sources, to build a comprehensive picture of the transitions in the region. We found that subsistence mixed farming systems transitioned to market-orientated specialized systems over a short time span. As the transition process gained momentum, households either intensified their production or got marginalized. Technological interventions, development programs with integrated approaches, and market demand for certain agricultural produce triggered increased regional production but also led to the scarcity of water, land, and labor. The transitions marginalized some of the households, changed the role of livestock in farming, and have been inclusive of both lower caste groups and women in terms of increased ownership of large ruminants and access to technologies. However, for women specifically, further increase in workload in the context of farming is also found. 相似文献
118.
Nicholas P. Guehlstorf 《Journal of Agricultural and Environmental Ethics》2008,21(6):541-558
In the beginning, policy debates between critics and advocates of genetically modified (GM) crops focused on scientifically
determined risks. Ten years later, the argument between environmentalists or consumers and regulators or industry has changed
into a discussion about the implementation of more democratic policymaking about GM farming. A notable omission from the political
debate about food biotechnology in the United States, however, is the opinion of farmers who cultivate the GM crops. Policymakers
should value practical knowledge based on experiences from farmers, not only scientific industry reports or consumer product
opinions. This project uses in-depth interviews to create an original mail survey that uses the practical discourse of farmers
in order to explore the relationship of farmer attitudes and GM agriculture. Although national research indicates that larger
yields are the most common reason for GM adoption, qualitative information suggest that the potential of GM crops to increase
revenue per acre does not truly reflect all the concerns of modern farmers. For example, farmers who use GM seeds indicate
that they constantly question the social impacts of their agricultural practices. As such, GM policies should be restructured
as a political rationalization of both economic modeling and political theory because this research suggests that farmers’
business decisions are utility calucations that consider economics without ignoring environmental and political contexts.
Farmers’ concerns about non-economic risks suggest that they need more information about GM crops and that governmental policies
should respond to their interests, as they are more democratic or pluralistic than industry or consumer arguments. 相似文献
119.
湿地农田低产土壤改良利用研究 总被引:5,自引:1,他引:4
系统地阐述了四湖地区湿地农田低产土壤的分布、成因、类型、特性及障碍因素,并着重对采取“三沟”配套排水、增肥调养、使用释氧化物、选手抗逆良种及轮作养地等综合改良利用技术的试验研究对果作了系统分析。 相似文献
120.
长江上游陡坡耕地退耕的难点与对策 总被引:2,自引:0,他引:2
长江上游属于 2 5°以上的陡坡退耕还林地面积达 170万hm2 ,是长江上游水土流失的重要策源地 ,严重制约了该区域社会经济的可持续发展。因此 ,实行陡坡耕地退耕还林是建设长江上游生态屏障的重要组成部分 ,也是生态建设的主要内容之一。本文较为系统地论述了陡坡耕地的形成原因与危害 ,以及退耕的难点与有利时机 ,并探讨了详细分析了主要对策 相似文献