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951.
During the last decades on the Spanish Mediterranean coastline there has been a great development of low-density urban areas, as well as a change in the sociodemographic structures, especially in the municipalities that have developed a residential tourism model. Likewise, urban and tourist development have stressed the balance between the availability of water resources and urban water demands, generating situations of scarcity that might be aggravated by climate change. This study identifies the determinants of water consumption on the Spanish Mediterranean coastline, focusing on the variables related to urban land uses and socioeconomic and sociodemographic variables at the municipal level using an ordinary least square (OLS) and a geographically weighted regression (GWR) model. The GWR model results substantially improved the results of the OLS model, explaining 88.27 percent of the variance in domestic water consumption and solving the spatial autocorrelation problem of some independent variables. The most influential variables include the percentage of second homes or the percentage of residential properties with swimming pools at the municipal level. These characteristics must be considered to develop demand management policies and an updated hydrological planning to ensure urban supply in a future with less available water resources.  相似文献   
952.
A change in economic structure influences the total energy consumption as well as CO2 emissions of a country, given the inherent difference in levels of energy intensity and energy fuel mix of different economic sectors. Its significance has been recognized in recent literature on China’s emission mitigation which could arguably raise China’s mitigation potential and thus the possibility of keeping the 2-degree trajectory on track. This article utilizes the past trend of economic structural change of five East Asian developed economies to project the energy consumption and CO2 emissions of China in the coming decades. A special delineation of the economic sector is made, putting private consumption together with the three typical economic production sectors, to resolve the mismatch between the statistical data of energy consumption and economic production, in that residential energy consumption is typically merged into the tertiary sector, although it does not directly correspond to gross domestic product (GDP) output. Results suggest that the level of CO2 emissions would be lower if China followed a development pathway emphasizing the development of the tertiary sector and continuously shrinking her secondary sector, making it possible for China to contribute more to global carbon mitigation. The impact from the rise of private consumption would be relatively insignificant compared to deindustrialization. In addition to continuous improvement in technology, economic structural change, which reduces carbon emission intensity, would be essential for China to be able to achieve the carbon emission level pledged in the Paris Agreement.

Key policy insights

  • For China, significant economic structural reform, particularly deindustrialization, is necessary to achieve the goal of ‘peak emission by 2030’.

  • Any additional contribution from China to the global effort to maintain a 2-degree trajectory would be limited – from a ‘fair-contribution’ perspective based on share of population or GDP – because the implied mitigation targets would be almost impossible to achieve.

  • If developing countries follow the pathway of developed economies, particularly in developing energy-intensive industries, energy consumption and CO2 emissions would significantly increase, reducing the possibility of keeping global temperature rise within the 2-degree Celsius benchmark.

  相似文献   
953.
文章使用云南1961—2015年观测气象资料和RegCM4区域气候模式模拟的RCP4.5和RCP8.5情景下2016—2099年气候变化预估资料,计算了云南逐日气候舒适度指数,采用线性趋势和通径分析等方法分析了云南近55年气候舒适度的时空演变特征和变化成因,最后对未来变化趋势作了预估。结果显示:(1)云南观测资料多年平均值舒适日数最多,占全年的55%,南多北少,夏季最多;寒冷日数次多,占全年的23%,北多南少,冬季最多;冷日数比寒冷日数稍少,占全年的20%;热日数仅占全年的1%,闷热日数多年平均值为零。(2) 1961—2015年寒冷(舒适)日数年际和空间变化都呈明显的减少(增加)趋势,冷和热日数没有明显的变化趋势,闷热日数没有变化。(3)气温是云南气候舒适度各等级日数变化的主要因素,其次是风速,相对湿度只在温度高的情况下影响明显。(4) RCP4.5和RCP8.5两种情景下,2016—2099年云南寒冷(舒适)日数年际和空间变化都是减少(增加)的趋势;冷日数年变化是减少的趋势,空间变化为西北部增加;热日数只在RCP8.5情景下增加明显,主要是南部地区增加。  相似文献   
954.
A cumulative emissions approach is increasingly used to inform mitigation policy. However, there are different interpretations of what ‘2°C’ implies. Here it is argued that cost-optimization models, commonly used to inform policy, typically underplay the urgency of 2°C mitigation. The alignment within many scenarios of optimistic assumptions on negative emissions technologies (NETs), with implausibly early peak emission dates and incremental short-term mitigation, delivers outcomes commensurate with 2°C commitments. In contrast, considering equity and socio-technical barriers to change, suggests a more challenging short-term agenda. To understand these different interpretations, short-term CO2 trends of the largest CO2 emitters, are assessed in relation to a constrained CO2 budget, coupled with a ‘what if’ assumption that negative emissions technologies fail at scale. The outcomes raise profound questions around high-level framings of mitigation policy. The article concludes that applying even weak equity criteria, challenges the feasibility of maintaining a 50% chance of avoiding 2°C without urgent mitigation efforts in the short-term. This highlights a need for greater engagement with: (1) the equity dimension of the Paris Agreement, (2) the sensitivity of constrained carbon budgets to short-term trends and (3) the climate risks for society posed by an almost ubiquitous inclusion of NETs within 2°C scenarios.

POLICY RELEVANCE

Since the Paris meeting, there is increased awareness that most policy ‘solutions’ commensurate with 2°C include widespread deployment of negative emissions technologies (NETs). Yet much less is understood about that option’s feasibility, compared with near-term efforts to curb energy demand. Moreover, the many different ways in which key information is synthesized for policy makers, clouds the ability of policy makers to make informed decisions. This article presents an alternative approach to consider what the Paris Agreement implies, if NETs are unable to deliver more carbon sinks than sources. It illustrates the scale of the climate challenge for policy makers, particularly if the Agreement’s aim to address ‘equity’ is accounted for. Here it is argued that much more attention needs to be paid to what CO2 reductions can be achieved in the short-term, rather than taking a risk that could render the Paris Agreement’s policy goals unachievable.  相似文献   

955.
基于2014—2016年南京市常规气象逐时观测数据、逐日用电量和逐时用电负荷数据, 分析南京市用电量变化及其与气象因子的关系。结果表明: 南京市用电量7—8月、12月至翌年1月为两个峰值, 4月和10月为两个谷值, 年变化明显。四季均呈现显著“周末效应”。用电负荷一天内有两个峰值, 分别出现在10时和20时; 两个谷值, 一个谷值冬夏季在04时, 另一谷值冬季在14时, 夏季在18时。南京市用电量与气象条件的变化密切相关, 气象因子与用电量的关系在不同月份有所不同, 如夏(秋、冬)季气温日较差越大(小), 用电量越大; 7月、8月(10月至翌年3月)气温越高(低), 用电量越大; 冬季用电量受气象要素的影响程度总体低于夏季。冬季用电量主要受气温制约; 夏季用电量受气象要素的影响更为复杂, 除了气温, 还需综合考虑水汽、日照等因子。利用逐步回归法, 建立冬、夏季逐月日用电量气象预测方程, 方程中入选气象因子的存在明显的月际差异。不同月份分别针对性地考量入选气象因子的预报值, 做出用电量预估, 可为电力调度提供参考。  相似文献   
956.
David Grigg 《GeoJournal》1998,44(1):9-18
A number of writers have argued that differences in food consumption between the countries in Europe are declining. This article investigates the possibility of convergence in the consumption of alcoholic beverages. The combination of beverages consumed in 1895–97, 1961–62 and 1994–95 is considered. This reveals three distinctive regions where wine, beer or spirits are the dominant drink. However, in this century the dominance of the staple drink has fallen and differences in total alcohol consumption have diminished, indicating convergence.  相似文献   
957.
Water consumption by households is influenced by a host of factors, widely investigated in the literature. However, the effects of contingent situations like drought episodes and economic crises, which may strongly restrict direct water use in households, remain less explored, and especially a combination of both. Catalonia, a Mediterranean region, suffered the worst drought episode in the last 75 years in 2007 and 2008, followed immediately by the worst economic crisis also in several decades between 2009 and 2014 (though still fishtailing). Taking it as a case study and using metered water data for the household sector, we propose a generalized linear mixed model in which the influence of both the drought episode and the economic crisis on per capita water consumption by comarques (supra-municipal entities) is assessed using a drought index on one hand, and economic variables and the water price on the other hand. Likewise, demographic, territorial and climatic determinants, as well as environmental behaviour, are also evaluated. The dataset (N = 287) consists of panel data for the forty-one comarques of Catalonia covering the 2007 to 2013 period. Results confirm that the contingent factors analysed have contributed to further reduce per capita water consumption, being significant the drought index and water price. The proportion of elderly people, the household size and the proxy for environmental behaviour, also have a negative effect on consumption; whereas seasonal population has the expected positive effect. However, neither the climatic and economic variables analysed, nor urban density and the proportion of foreign population, are found to be significant. A better understanding of the factors influencing residential water consumption in a context of growing water scarcity and economic downturn may aid policy makers and water managers not only to improve the effectiveness and efficiency of demand-side management measures that affect households, but to address emerging social concerns such as water poverty.  相似文献   
958.
Remotely sensed nighttime light (NTL) from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) provides a spatially consistent and cost-effective mean to estimate energy consumption pattern. While previous researches have documented the application of NTL to predict electric power consumption (EPC) with varying degrees of success, few have systematically studied the possible factors affecting the EPC-NTL relationship. Moreover, no substantial research effort has been made to relate overall energy consumption (OEC) to NTL. This study investigated key factors governing the EPC/OEC-NTL relationship by examining the influences of affluence, urbanization, technology, temperature, and NTL pattern. Results show that EPC increased with higher per capital GDP, urbanization rate, and high-technology exports, and lower agricultural development, both globally and regionally. Meanwhile, EPC generally reduced with higher temperature and more agglomerate human activities. A strong OEC-NTL relationship was found; but the influencing factors to the OEC-NTL relationship varied across regions due to the natures of energy use. These factors must be considered especially for the studies of less-affluent regions where NTL was undetectable by the DMSP-OLS sensor.  相似文献   
959.
节能和就业导向下中国中部地区产业结构优化   总被引:1,自引:0,他引:1  
产业结构优化是人文—经济地理学重要的研究对象,也是政府部门加强宏观调控的作用对象,更是近年来中国步入“新常态”面临的现实问题。研究采用多区域投入产出模型,结合线性规划,构建了节能和就业导向下产业结构整体最优的模型和优化度模型。结果表明:① 节能导向下,安徽的产业结构优化度最高(0.763),山西的产业结构优化度最低(0.662);就业导向下,江西的产业结构优化度最高(0.768),山西的产业结构优化度最低(0.659)。② 节能导向下,产业结构优化度与单位产值能耗、重工业比重负相关;就业导向下,产业结构优化度与国有经济比重、大型企业比重负相关。③ 如果考虑节能和就业不同的目标导向,中国中部6省之间产业结构优化的方向存在明显的差异。④ 整体看,中国中部地区应保持不变或适度提高资源型产业比重,较大提高交通运输设备制造业、通信设备、计算机及其他电子设备制造业等现代制造业的比重,适度降低金属冶炼及压延加工业、非金属矿物制品业等比重。在服务业方面,较大提高燃气及水的生产和供应业、旅游业等比重,适度降低或较大降低批发零售业和餐饮业的比重,保持不变或适度降低交通运输及仓储业的比重。  相似文献   
960.
中国省域城镇居民碳排放驱动因素分析   总被引:5,自引:3,他引:2  
刘晔  刘丹  张林秀 《地理科学》2016,36(5):691-696
从消费角度出发,分别对2003和2012年中国城镇(不含港、澳、台地区)居民碳排放的特征及影响因素进行分析。结果显示,不同地区城镇居民碳排放存在明显差异,人口因素对区域分异有弱化作用。从城镇居民人均碳排放来看,不同地区消费构成、能源结构、产业结构3因素对城镇居民碳排放影响的差异总体表现为:消费结构/能源结构>产业结构。与其他部门相比,大多数地区工业部门的生产能耗、投入产出周转量和产品购买量是影响当地城镇居民碳排放的主要因素,各地区城镇居民碳排放的影响因素具有明显的区域特点。政府应在当前研究的基础上,根据当地能耗模式、产业模式和消费模式因地置宜管理城镇居民碳排放。  相似文献   
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