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491.
492.
城市旅游发展的动力:理论分析与案例研究   总被引:14,自引:0,他引:14  
20世纪80年代之初,深圳和珠海旅游发展的内外部条件极为类似,但是20年来两个城市旅游的发展模式却完全不同。本文研究发现:城市旅游发展取决于需求结构和相对优势两个因素的共同作用。基于旅游体验本质的需求结构的变化,决定了同一类型的旅游城市具有相似的变化规律;不同类型的旅游城市变化规律差异较大。另一方面,城市旅游驱动机制决定了相对优势的变化,旅游驱动机制演变轨迹的不同正是建成各个城市旅游目的地旅游发展模式差别的主因。由此可见,城市旅游要实现可持续发展就必须用随外部环境的变化(主要是需求结构的变化),适时培育和转变驱动机制。  相似文献   
493.
乡村振兴与新型城镇化耦合协调的动态演进及其驱动机制   总被引:11,自引:0,他引:11  
重构乡村振兴与新型城镇化的指标体系,采用耦合协调度模型、空间马尔可夫链以及地理加权回归模型,分析了2005—2017年中国30个省(市、自治区)乡村振兴与新型城镇化的耦合协调水平、时空分异格局、空间动态演进以及驱动机制。研究发现:(1)乡村振兴与新型城镇化的耦合协调度呈现“东部高、西南低”的分布特征,中级协调区域逐步向中部扩散,高级协调区域数量不断增加;高级协调类型省(市、自治区)中“乡村振兴滞后型”占大多数,初级协调和濒临失调类型省(市、自治区)中“新型城镇化发展滞后型”居多。(2)耦合协调度的动态演进呈现维持原有状态稳定性的特征,较难实现跨越式转移,处于高级协调阶段的省(市、自治区)存在“俱乐部趋同”现象。向上转移的省(市、自治区)主要集中在中部,向下调整的以北方省(市、自治区)居多;耦合协调较高的省(市、自治区)对邻近省(市、自治区)具有正向溢出效应,而耦合协调度低的省(市、自治区)对周围产生负向效应,且这种影响是不对称的。(3)影响乡村振兴与新型城镇化耦合协调度变化的驱动力空间差异显著,表现出层级带状分布的发展态势。政府驱动、投资驱动、人口驱动呈现南北层级带状分布。消费驱动、收入驱动、产业驱动呈现东西层级带状分布。  相似文献   
494.
Abstract: The important role of humans in the development of current ecosystems was recognized decades ago; however, the integration of history and ecology in order to inform conservation has been difficult. We identified four issues that hinder historical ecological research and considered possible solutions. First, differences in concepts and methods between the fields of ecology and history are thought to be large. However, most differences stem from miscommunication between ecologists and historians and are less substantial than is usually assumed. Cooperation can be achieved by focusing on the features ecology and history have in common and through understanding and acceptance of differing points of view. Second, historical ecological research is often hampered by differences in spatial and temporal scales between ecology and history. We argue that historical ecological research can only be conducted at extents for which sources in both disciplines have comparable resolutions. Researchers must begin by clearly defining the relevant scales for the given purpose. Third, periods for which quantitative historical sources are not easily accessible (before AD 1800) have been neglected in historical ecological research. Because data from periods before 1800 are as relevant to the current state of ecosystems as more recent data, we suggest that historical ecologists actively seek out data from before 1800 and apply analytic methods commonly used in ecology to these data. Fourth, humans are not usually considered an intrinsic ecological factor in current ecological research. In our view, human societies should be acknowledged as integral parts of ecosystems and societal processes should be recognized as driving forces of ecosystem change.  相似文献   
495.
为探究武南区域重点河流水质的变化规律、驱动因素以及河流治理成效,基于2006~2018年连续水质监测数据,综合分析了4条重点河流(太滆运河、武宜运河、武进港和永安河)水质演变趋势,并对污染较重的永安河各项水质指标进行了季节性分析和相关性分析.结果表明:2006~2018年,4条河流水质整体呈好转趋势,修正内梅罗指数分别下降36.2%,31.5%,56.4%,48.7%,受河流清淤工程影响,永安河2017年水质有所下降;4条河流氨氮浓度、总氮浓度与高锰酸盐指数下降趋势明显(P<0.05),总磷浓度则存在一定波动;永安河的总氮、氨氮和高锰酸盐指数间或存在同源关系,氨氮和总氮季节性变化明显,雨季浓度低于旱季,总磷和高锰酸盐指数没有明显季节性变化趋势;城镇化发展与产业结构由传统工业、农业向第三产业的转变均对区域水环境改善有积极作用.  相似文献   
496.
The potential for mitigating climate change is growing worldwide, with an increasing emphasis on reducing CO2 emissions and minimising the impact on the environment. African continent is faced with the unique challenge of climate change whilst coping with extreme poverty, explosive population growth and economic difficulties. CO2 emission patterns in Africa are analysed in this study to understand primary CO2 sources and underlying driving forces further. Data are examined using gravity model, logarithmic mean divisia index and Tapio's decoupling indicator of CO2 emissions from economic development in 20 selected African countries during 1984?2014. Results reveal that CO2 emissions increased by 2.11% (453.73 million ton) over the research period. Gravity centre for African CO2 emissions had shifted towards the northeast direction. Population and economic growth were primary driving forces of CO2 emissions. Industrial structure and emission efficiency effects partially offset the growth of CO2 emissions. The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement. Industrial structure and emission efficiency were insufficient to decouple economic development from CO2 emissions and relieve the pressure of population explosion on CO2 emissions in Africa. Thus, future efforts in reducing CO2 emissions should focus on scale-up energy-efficient technologies, renewable energy update, emission pricing and long-term green development towards sustainable development goals by 2030.  相似文献   
497.
为了评估中国大气环境治理带来的健康效益,确定健康风险评价的主要驱动因素,本文使用结合人群活动因子的综合暴露响应模型,对中国东部和中部地区2013~2017年可归因于PM2.5的健康经济效益进行了估算,并量化了人口总量、人口老龄化、基准死亡率和PM2.5暴露浓度这4个因素对健康负担的影响贡献.结果表明,2013~2017年研究区域内PM2.5人口加权浓度下降了28.73%,PM2.5年均暴露浓度在35 μg·m-3及以下的人口比例从11.23%增加到27.91%.PM2.5浓度下降使得2017年归因死亡数下降了14.43%,可避免经济损失为5588.41亿元.当PM2.5暴露浓度达到国家二级标准(35 μg·m-3)、一级标准(15 μg·m-3)和世卫组织建议标准(10 μg·m-3)时,归因死亡人数较基准年(2017年)将减少8.22%、55.05%和79.36%,避免经济损失3190.85、21374.38和30812.97亿元.人口总量、人口老龄化、基准死亡率和PM2.5暴露浓度这4个因素对健康负担的贡献分别为-2.69%、-12.38%、1.66%和14.57%,其中污染物浓度降低是减轻健康负担的主导因素.中国的大气污染治理取得了显著成效,但在高PM2.5浓度和高人口密度的地区,大气污染导致的健康负担仍然很重,需要实施更加严格的空气污染控制政策.  相似文献   
498.
定量分析碳排放驱动因素,对优化能源结构、调整产业结构、推进技术进步、发展低碳经济具有重要的理论和现实意义.利用碳排放估算模型,测算了黑龙江省1995-2012年能源消费的碳排放量.基于扩展的STIRPAT模型,实证研究了各驱动因子对碳排放总量的影响及其驱动程度.结果表明,能源结构、经济发展水平、城市化率、人口总量对碳排放量有正向驱动作用,而产业结构、能源强度对碳排放总量的增加具有抑制作用,提出有效促进能源消费结构优化、加大产业结构调整、大力推进技术创新是实现黑龙江省低碳经济发展的有效路径.  相似文献   
499.
By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism in China from 1995 to 2009.According to the results,we drew the following conclusions:(1)The regional difference of domestic tourism in China tends to be narrowing generally,and is less than that of inbound tourism,playing an important role in narrowing the overall gap of regional tourism in China.(2)The regional internal difference features:inter-provincial difference in the eastern region and difference among the eastern,central and western regions are comparatively obvious and demonstrate a significantly shrinking tendency,the change tendency is consistent with the change tendency of overall difference and exercises a decisive role in overall difference,whereas the inter-provincial difference in the central and western regions is small and relatively stable,having less influence on the overall difference.(3)The temporal-spatial change in regional difference is featured by:low-level provinces occupy a majority and are concentrated in the central and western regions,showing a tendency of narrowing difference;high-level provinces are concentrated in the eastern region,showing a tendency of spreading to the central and western regions;spatial pattern of regional difference demonstrates 4 types,i.e."proliferation type","polarization type","quiescence type"and"collapse type."(4)The driving force for regional difference of domestic tourism in China comes down to 3 aspects:regional socio-economic attribute,regional transport accessibility level and regional development policy.  相似文献   
500.
Abstract

Increasing populations are causing an increase in food demands, and the area of cultivated land expands every year. Inappropriate land transition from ecology to production results in the constant decline of the ecological security level and influences the regional sustainable development. Adjusting unreasonable land use mode and reconstructing natural land cover are important ways to maintain and improve the ecological environment. Also reclaiming farmland as areas for forests and grasslands (FRFG) is another way. Successful implementation of FRFG in China is the result of comprehensive effect of the multi-scales driving forces. This paper analyses the driving forces of FRFG in China on a national (country)—regional (province)—local (county)—household (farmer) level scale, and the results are: driving forces at the national scale include ecological and food security and the western development of China; at the regional scale, ecological and economic benefits become the main factors to influence the dimension of FRFG under the same policy. The driving forces can be divided into 6 types: industrial structure adjustment, water source protection, flood prevention, the Three-Gorge Project protection, reduction of the amount of sediment flowing into the Yellow River and wind erosion desertification prevention. The driving forces at the local scale can be divided into 12 types with developing leading industries, increasing farmers' income and improving agricultural production conditions as the main types; at the household scale, the national policy meeting farmers' demands and the optimization of individual interests are all driving forces.  相似文献   
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