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31.
This article describes a method for determining the environmental load of Dutch private consumption. The method generates detailed information about consumption-related environmental impacts. The environmental load of households (direct) and production (indirect) was determined for 360 expenditure categories reported in the Dutch Expenditure Survey. The indirect environmental load was calculated with linked input-output tables covering worldwide production and trade. The environmental load per Euro turnover of industries was linked to consumer expenditures. With this method we can quantify several types of environmental load per expenditure category and per economic production region.
It was found that food production, room heating, and car use are the most important elements in the environmental load of Dutch private consumption. The impacts taking place abroad were—with the exception of emission of greenhouse gases and road traffic noise—found to be larger than domestic impacts. Most land use was found to take place in developing (non-OECD) countries, whereas most emissions occur in industrialized (OECD) countries.  相似文献   
32.
张雯  刘倩倩  王慧  陈彬 《生态学报》2023,43(12):4943-4953
高强度农业开发引起的农业水土资源生态问题日益增多,探究粮食及蔬菜(粮蔬)生产中水土资源空间配置及短缺压力对农业资源的可持续利用具有重要意义。从水足迹视角出发,分析了山东省3种主要粮食作物(冬小麦、玉米及大豆)和两种不同种植模式蔬菜(设施蔬菜和露地蔬菜)的生产水足迹空间特征;同时将资源数量及资源质量的概念纳入研究框架,分析了农业水土资源数量及质量匹配格局差异,并进一步探究了农业水土资源短缺压力及其影响因素。研究结果表明:(1)2019年,山东省粮食和蔬菜的生产总水足迹为811亿m3,其中粮食生产总水足迹占比78.50%,蔬菜生产总水足迹占比21.50%;粮蔬生产水足迹受地势影响明显,鲁西北及鲁西南平原地区的粮蔬生产水足迹占比较大。(2)考虑资源数量的水土资源匹配系数均值为0.622×104 m3/hm2,考虑资源质量的匹配系数均值为0.416×104 m3/hm2;水土资源数量及质量匹配系数在空间上呈现出一致性,表明山东省农业生产水土资源空间配置水平高的地区同时面临着较大的农业面源污染压力。(3)整体上,土地资源短缺压力略高于水资源短缺压力;基于生产视角的水土资源短缺压力受生产环境因素制约显著,受经济发展因素的影响具有差异性,社会因素对水土资源短缺压力无显著影响。研究可为农业资源可持续管理提供数据基础,为全面理解粮蔬生产所产生的水土资源短缺提供案例参考。  相似文献   
33.
云南省农田生态系统碳足迹时空变化及其影响因素   总被引:4,自引:0,他引:4  
李明琦  刘世梁  武雪  孙永秀  侯笑云  赵爽 《生态学报》2018,38(24):8822-8834
农田碳足迹研究对农田生态系统管理与农业可持续发展具有重要意义,也可表征农田扩展的生态影响程度。利用县域尺度统计数据与空间分析,对云南省农田生态系统近30年的碳足迹的时空演变进行研究。结果表明:1985—2015年期间,云南省农田生态系统碳排放年均增幅为13.9%,化肥施用引起的碳排放贡献率最大,为56%,2015年的化肥单位面积碳排放达到331.6kg/hm2。云南省农田生态系统碳吸收年均增幅为3.04%,稻谷的碳吸收比例最大,为41%,然而,玉米的碳吸收的增幅最大,为8.76%。云南省农田生态系统存在碳生态盈余,且碳足迹总体呈现增长趋势,年均增长率为16.8%,单位面积碳足迹随年份增加不断增长。从空间上看,云南省农田生态系统碳排放、碳吸收在空间上均呈东南高、西北低的分布格局,而碳足迹在空间上呈现东西部高、中部低的分布格局,三者的空间差异和变化幅度差异都较大。  相似文献   
34.
The present article aims to determine the current carbon footprint (CF) of Zernez, a Swiss mountain village, and to identify reduction potentials of greenhouse gas (GHG) emissions. For this purpose, material and energy flows were assessed mainly based on detailed household surveys, interviews, and energy bills, but also by means of other information sources, for example, national statistics, traffic censuses, and literature values. To set up the GHG balance, special attention was paid to the consistent definition of system boundaries by adopting two fundamentally different perspectives: purely geographical accounting (PGA) and the consumption‐based footprint (CBF) method. Each of these two perspectives total approximately 10 tonnes of carbon dioxide equivalents per capita per year. The PGA revealed that 70% of the direct emissions in Zernez are caused by agricultural activities, whereas no consumption area dominated the consumption‐induced CF. For the identification of targeted measures, both perspectives were considered in a complementary manner. The building stock and its underlying energy supply system showed a GHG reduction potential of 80%. The building sector was thus detected as a reasonable first step for the municipality to adopt GHG mitigation strategies. In the case of Zernez, building‐stock‐related measures are predicted to decrease the current CF by 13% (CBF) and 17% (PGA), respectively.  相似文献   
35.
城市水资源生态足迹核算模型及应用——以沈阳市为例   总被引:11,自引:0,他引:11  
水资源生态足迹可以直接反映区域人类社会经济活动对水资源的压力.本研究在现有的生态足迹模型基础上,充分考虑城市自然生态系统对水资源的需求,建立了包括居民日常生活用水、生产运营用水、公共服务用水和生态需水4类帐户的城市水资源生态足迹核算模型,并结合沈阳市实际情况,确定了模型中的相关参数,对沈阳市水资源生态足迹和生态承载力进行分析.结果表明:2000-2009年,沈阳市人均水资源生态足迹总体呈下降态势,但各年度均为水生态赤字;2005年较2000年水资源生态足迹人均下降0.31 hm2,2006、2007年有小幅回升,2008、2009年趋于平稳,说明沈阳市水资源可持续利用状况有一定改善,但仍处于不可持续状态.  相似文献   
36.
在快速工业化和城镇化的影响下,农业文化遗产的保护与管理正面临着适龄劳动力大量外流、土地抛荒、传统知识体系难以维持等诸多威胁与挑战。推动土地流转、进行适度规模经营,可在农业文化遗产的保护中产生积极作用。土地流转在给遗产地带来经济效益的同时,对当地生态环境产生的影响变化同样值得关注,但现有研究却少有涉及。本研究以全球重要农业文化遗产——浙江青田稻鱼共生系统为例,将不同经营规模的稻鱼共生系统分为小农户经营模式和规模化经营模式,运用生命周期法对两种模式的碳足迹进行核算。结果表明: 小农户经营模式和规模化经营模式的碳足迹分别为6510.80和5917.00 kg CO2-eq·hm-2,单位产值碳足迹分别为0.13和0.10 kg CO2-eq·yuan-1。与小农户经营模式相比,规模化经营模式温室气体排放更少,单位产值的环境影响更小。农户扩大经营规模后,当地温室气体排放减少了4097.20 kg CO2-eq。农业生产过程中积累的CH4在碳足迹中占比最大,农业生产资料中复合肥是仅次于CH4的第二大温室气体排放来源。对于小农户经营模式,饲料中使用的玉米和小麦也对温室气体排放有重要的影响。因此,推动土地适度规模经营,有利于传统农业系统实现经济效益和环境效益的双赢,对于农业文化遗产保护具有重要作用。  相似文献   
37.
Life cycle impact of emissions, energy requirements, and exergetic losses are calculated for a novel process for producing titanium dioxide nanoparticles from an ilmenite feedstock. The Altairnano hydrochloride process analyzed is tailored for the production of nanoscale particles, unlike established commercial processes. The life cycle energy requirements for the production of these particles is compared with that of traditional building materials on a per unit mass basis. The environmental impact assessment and energy analysis results both emphasize the use of nonrenewable fossil fuels in the upstream life cycle. Exergy analysis shows fuel losses to be secondary to material losses, particularly in the mining of ilmenite ore. These analyses are based on the same inventory data. The main contributions of this work are to provide life cycle inventory of a nanomanufacturing process and reveal potential insights from exergy analysis that are not available from other methods.  相似文献   
38.
2004—2013年东北三省主要粮食作物生产碳足迹   总被引:1,自引:0,他引:1  
东北是我国重要的粮食主产区,在国家粮食安全保障中起着至关重要的作用.作物生产是主要的碳排放源,探明不同作物生产的碳足迹差异,对促进低碳农业发展具有重要意义.本研究利用2004—2013年东北三省主要粮食作物(水稻、玉米和大豆)的产量、播种面积、农田生产投入等统计数据,估算了该区粮食生产碳足迹.结果表明: 2004—2013年,东北地区3种主要粮食作物中,水稻生产单位面积碳足迹最高,平均达到(2463±56) kg CE·hm-2,玉米次之.玉米的碳足迹上升趋势最明显,从2004年的1164 kg CE·hm-2增加到2013年的1768 kg CE·hm-2,增速为67 kg CE·hm-2·a-1.在碳足迹构成中,化肥贡献最大,分别占水稻、玉米、大豆总碳投入的45%、90%、83%.水稻生产中灌溉用电所占比例为29%~42%,远高于玉米和大豆.东北三省碳足迹差异显著,3种作物的单位产量碳足迹均在吉林省最高,单位面积碳足迹均在黑龙江省最低.随着农村劳动力非农化和作物生产机械化的快速递增,未来粮食生产中柴油等机械化碳投入将快速增长.提升化肥利用效率、灌溉效率和机械化作业效率将是发展东北地区低碳农业的关键途径.  相似文献   
39.
采用能值-生态足迹模型,对辽宁省2003—2012年生态安全状况进行时间序列的定量分析与评价,并采用灰色动力学模型预测其动态变化趋势.结果表明: 研究期内辽宁省人均能值生态承载力从3.13 hm2下降到3.07 hm2,人均能值生态足迹由13.88 hm2增加到21.96 hm2,处于生态赤字状态,且赤字增大趋势明显;生态压力指数由4.43增长到7.16,生态安全预警等级由轻警过渡到中警程度.照此发展,2013—2022年辽宁省人均能值生态承载力将由3.04 hm2下降到2.98 hm2,人均能值生态足迹将由22.72 hm2上升到35.87 hm2;生态赤字将越来越大,生态压力指数将由7.46上升到12.04,生态安全等级将由较安全变为轻度不安全状态,并呈现由中警到重警的生态安全预警等级,生态安全问题亟待解决.  相似文献   
40.
Biodiversity loss can be accelerated by human consumption in regions that are far removed from habitat degradation because of economic globalization, but no study has directly quantified the effects of global trade on extinction risks at a global scale with consideration for species differences. We propose a novel biodiversity footprint index based on bird extinction risks to evaluate the effects of global wood production and trade on biodiversity. Using 536 endangered bird species threatened by wood harvesting and logging, we calculated the “quasi-extinction” probabilities, that is, the probabilities that population sizes become lower than an extinction threshold after habitat loss based on initial population sizes and forest habitat loss rates. We then used bilateral wood trade data to link the biodiversity impacts in wood exporters to wood importers. We found that if recent trends in forest cover loss continue until 2100, bird species in Brazil would be the most rapidly and heavily affected by wood production and trade, followed by those in Indonesia; these two countries alone would account for about half of all global bird extinctions. Large-scale wood importers (i.e., China, Japan, and the United States) significantly elevate overseas extinction risks and, simultaneously, reduce domestic impacts, indicating a heavy responsibility of these countries for global biodiversity loss. We also conducted a scenario analysis, which showed that the total projected number of extinct species would not decrease if each country produced the amount of wood materials necessary to meet current consumption levels. This is because bird extinction risks in tropical wood importers, such as Mexico and the Philippines, as well as Japan and China will increase if these countries increase domestic wood production. Our biodiversity footprint index is useful to identify countries whose bird species are highly affected by wood production and trade, and to quantify the role of wood trade in bird species extinctions. Additional scenario analyses are needed to establish effective patterns of wood production and consumption for bird biodiversity conservation.  相似文献   
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