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31.
This paper addresses issues of access to land for food production in Toronto by offering fresh perspectives on urban agriculture in the neo-liberal city of the global north. It examines attempts to scale up urban agriculture that emphasise changing the relationships between land access, property and new collaborative relationships among different stakeholders. These initiatives involve renegotiating access to land for growing food between private property owners and landless growers, concomitant shifts in control over valued resources and commercialisation. These shifts are often based on relations of trust within a sharing economy rather than public battles over political decisions to develop urban agriculture lands. Growing food on private lands in the city is political in challenging taken-for-granted ideas and practices of property and urban agriculture. New approaches offer options for training and income, as well as expanding the land base for urban agriculture. Small-scale farming projects are affirmative political manoeuvres. They challenge urban residents to consider land for food production across the categories of public and private property. We document three approaches that challenge current property relations: temporary use of a development site through “soft” squatting; redesignating suburban backyards for farmer training and community-based and private food production; and garden sharing of private home backyards for urban food production and commercial growing. Such initiatives articulate alternative visions of sustainability and food security that rely on principles of collaboration and a sharing economy that challenge prevailing notions of property ownership and food security.  相似文献   
32.
增施磷肥对提高强酸性高硒茶园土壤硒有效性的效果   总被引:3,自引:0,他引:3  
通过大田试验,研究了增施钙镁磷肥、过磷酸钙及与生物有机肥混施共6种调控措施对强酸性高硒茶园土壤基本化学性质、土壤有效硒和茶叶中硒质量比的调控效果.结果表明,不同磷肥及不同用量处理对土壤有效硒质量比增加均有效果,高用量的3种处理(钙镁磷肥高用量与生物有机肥混施、钙镁磷肥高用量和过磷酸钙高用量)效果好于正常用量的处理(钙镁磷肥正常用量与生物有机肥混施、钙镁磷肥正常用量、过磷酸钙正常用量),且用量相同的情况下,伴有生物有机肥的磷肥处理效果最好.增施磷肥调控均不同程度地增加了茶叶硒质量比,6种处理的增幅均达到极显著水平(p<0.01).  相似文献   
33.
论我国城市生态园林公墓建设及其发展   总被引:5,自引:0,他引:5  
随着工业占地的加剧和城市死亡人数的增长,城市公墓建设的不合理问题已非常尖锐,使得城市可用土地面积和人均绿地减少。因此,在我国实施城市生态园林公墓建设已迫在眉睫。本文就此指出了一些当前我国生态园林公墓建设中存在的问题,并提出了几点措施和建议。  相似文献   
34.
The effects of eleven pesticides on the populations of bacteria, actinomycetes, fungi and protozoa was investigated by treating a garden soil with their recommended rates. The microbial populations were estimated using the standard plate-count technique. Of the ll pesticides investigated, phenylmercuric acetate (agrosan) at 50 g g-1 inhibited bacterial density the most, i.e. from 4,600,000 to 220 cells g-1. The pesticides were Pentachloronitrobenzene (PCNB), tetramethylmethylthiuram disulphide (thiram),1- naphthylmethylcarbamate (Vetox 85), 1,2,3,4,5,6-hexachlorocyclohexane (Gammalin 20), phenylmercuric acetate (Agrosan), tetrachloroterephthalic acid (Dacthal), 4-nitrophenyl –2-nitro-4-trifluoromethylphenyl ether (Preforan), 2-ethyl-6-methyl –N-2-methoxy –1-methyl ethyl-chloroacetanide (Dual), Benlate, Brestan and Gramoxone. Pentachloronitrobenzene (PCNB) at 240,000 g g-1 reduced bacterial population from 4,600,000 to 2,100 cells g-1, whereas tetramethylthiuram disulphide (thiram) at 100 g g-1 suppressed it by 2 log orders of magnitude. Soil application of 1-naphthylmethylcarbamate (Vetox 85) at 100 g g-1 and 1,2,3,4,5,6,-hexachlorocyclohexane (Gamalin 20) at 1,300 g g-1 repressed the bacterial numbers by 2 log orders of magnitude each. Pentachloronitrobenzene reduced the actinomycetes density from 340,000 to 320 cells g-1 and completely eliminated all fungal and protozoan propagules from the soil. The Gammalin 20 completely wiped out all the fungi, whereas phenylmercuric acetate totally eliminated all the protozoa and reduced the fungal population from 34,000 to 60 cells g-1. In general, protozoa and fungi were more susceptible to fungicides than bacteria and actinomycetes. Pentachloronitrobenzene, 1,2,3,4,5,6,-hexachlorocyclohexane and phenylmercuric acetate were toxic particularly to soil microorganisms, whereas the herbicides dacthal, Preforan and Dual were quite harmless in soil at application rates of 0.1, 0.06 and 0.02 g g-1 respectively.  相似文献   
35.
客观地介绍了循环经济产生的社会背景及发展趋势、国内外发展循环经济的成功经验,阐述了发展循环经济的理论基础及实践意义,详细地提出了秦皇岛市发展循环经济的奋斗目标、实施对策.  相似文献   
36.
The small-rodent populations of five collective gardens have been studied. The example of one of the populations has been used to monitor the annual cycle of population size. The species composition and animal number depends on the biotope, climatic conditions, and the anthropogenic load. The ratios between species in the gardens and neighboring biotopes differ from each other, with different species being dominant. It is assumed that small mammals use garden plots as refugia.  相似文献   
37.
When conservation strategies require new, field‐based information, practitioners must find the best ways to rapidly deliver high‐quality survey data. To address this challenge, several rapid‐assessment approaches have been developed since the early 1990s. These typically involve large areas, take many months to complete, and are not appropriate when conservation‐relevant survey data are urgently needed for a specific locale. In contrast, bioblitzes are designed for quick collection of site‐specific survey data. Although bioblitzes are commonly used to achieve educational or public‐engagement goals, conservation practitioners are increasingly using a modified bioblitz approach to generate conservation‐relevant data while simultaneously enhancing research capacity and building working partnerships focused on conservation concerns. We term these modified events expert bioblitzes. Several expert bioblitzes have taken place on lands of conservation concern in Southern California and have involved collaborative efforts of government agencies, nonprofit organizations, botanic gardens, museums, and universities. The results of expert bioblitzes directly informed on‐the‐ground conservation and decision‐making; increased capacity for rapid deployment of expert bioblitzes in the future; and fostered collaboration and communication among taxonomically and institutionally diverse experts. As research and conservation funding becomes increasingly scarce, expert bioblitzes can play an increasingly important role in biodiversity conservation.  相似文献   
38.
基于GIS的贵州省茶园生态适宜性研究   总被引:3,自引:0,他引:3  
通过利用GIS技术,在土地利用现状以及喀斯特空间分布的基础上初步划分茶叶种植适宜地和不适宜地。选择对茶叶生长密切相关的地形地貌(海拔、坡度、坡向)、气候条件(光、热、降水条件及空气相对湿度)及土壤条件(土壤pH值)等8个生态评价因子,通过专家打分确定各因子权重,应用GIS空间叠加分析模块实现贵州茶园生态适宜性评价。结果表明:贵州省适宜茶叶种植的面积为32417.00km2,占国土面积的18.40%,其中非常适宜种植茶叶的区域面积为10618.00km2,占国土面积的6.03%;适宜种植茶叶的区域面积为11554.00km2,占国土面积的6.56%;比较适宜种植茶叶的区域面积为10245.00km2,占国土面积的5.81%;不适宜种植茶叶的区域面积为143735.45km2,占国土面积的81.60%。以上评价结果将为贵州茶产业的大力发展提供科学依据和技术基础。  相似文献   
39.
粤东凤凰山茶区土壤氟化学形态特征及其影响因素   总被引:2,自引:0,他引:2  
李张伟 《环境化学》2011,30(8):1468-1473
采用连续化学提取法对粤东凤凰山茶区12个较大型茶园共60份土壤样品氟的5种化学形态分布进行研究.结果发现,土壤中氟的5种化学形态分布的规律为残余态〉〉铁锰结合态〉有机态〉水溶态〉可交换态.水溶态氟含量与可交换态氟含量、残余态氟含量及总氟含量呈显著正相关性,而铁锰结合态含量与有机束缚态之间呈显著正相关性,残余态与总氟之间...  相似文献   
40.
从群落生态学的角度对茶园节肢动物群落动态变化进行了初步探讨.通过对安徽省黄山市休宁县农家茶园的调查,获得了关于茶园节肢动物群落的组成、个体数量及其物种数等数据.结果表明,4-5月份茶园一般不需要进行施药防治,此时天敌种类和数量相对较多,对害虫起控制作用,这一时期应做好害虫测报和防治准备,为茶农防治茶园害虫提供科学方法.  相似文献   
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