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141.
吴希龙 《地下水》2002,24(1):21-24
水污染是我国面临的最主要的水环境问题。本文在分析泰安市水污染现状、原因的基础上,提出了水污染物总量控制方案,探讨了从根本上治理水污染的对策。  相似文献   
142.
工业废水和城市生活污水的大量排放、已使安帮河的水质恶化,水质监测结果表明,安帮河水为严重污染水,并已危及了地下水水源地,而且还有进一步发展的趋势,因此文中提出,治理安帮河污染已是刻不容缓,否则双鸭山市将成为缺水城市。  相似文献   
143.
144.
废弃物处理温室气体排放的主要排放源之一为废水(生活污水和工业废水)处理CH4排放。根据统计资料和IPCC提供的方法,选择适合中国的排放因子,分析了中国废水处理2005-2010年的CH4排放特征和2000-2010年CH4产生的各驱动因子。并且根据中国的实际情况预测和分析了中国废水处理CH4排放趋势和排放潜力。结果显示:2010年中国生活污水处理CH4排放量为61.10万t,工业废水处理的CH4排放量为162.37万t,造纸等八大行业CH4排放量达到总CH4排放量的92%以上,2005-2010年的CH4排放量逐年增加;到2020年在减排情景下,生活污水处理CH4排放量为101.36万t,减排潜力为7.63万t,比2010年排放量增加了66%;工业废水处理CH4排放量233.93万t,减排潜力为25.99万t,比2010年排放量增加了44%。  相似文献   
145.
一次能源消费导致的二氧化碳排放量变化   总被引:12,自引:4,他引:8  
郭义强  郑景云  葛全胜 《地理研究》2010,29(6):1027-1036
从不同燃料和不同地区入手,分析了我国1995~2006年间一次能源消费导致的二氧化碳排放量变化情况。结果表明:1995~2006年间,我国一次能源消费导致的二氧化碳年总排放量呈现"先减少后增加"的发展态势,其拐点出现在2000年,而且2001年后各个省(区、市)的二氧化碳年排放量较前期均有大幅度的增加,总排放量由1995年的78678万t碳增长到2006年的146919万t碳,年均增长率5.84%,人均二氧化碳年排放量也由0.62t碳/人增加到1.12t碳/人;煤炭消费导致的二氧化碳排放量占全国二氧化碳年总排放量的79%~85%;我国七大区和大部分省(区、市)二氧化碳年排放量与全国总排放量有类似的发展态势,其中华北、华东地区二氧化碳排放量居全国首位,山西省的二氧化碳排放量位居全国第一。  相似文献   
146.
Methane (CH4) emissions estimated with the Intergovernmental Panel on Climate Change (IPCC) inventory method at the city and regional scale are subject to large uncertainties.In this study,we determined the CH4:CO2 emissions ratio for both Nanjing and the Yangtze River Delta (YRD),using the atmospheric CH4 and CO2 concentrations measured at a suburban site in Nanjing in the winter.The atmospheric estimate of the CH4:CO2 emissions ratio was in reasonable agreement with that calculated using the IPCC method for the YRD (within 20%),but was 200% greater for the municipality of Nanjing.The most likely reason for the discrepancy is that emissions from unmanaged landfills are omitted from the official statistics on garbage production.  相似文献   
147.
Carbon sequestration occurs when cultivated soils are re-vegetated. In the hilly area of the Loess Plateau, China, black locust(Robinia pseudoacacia) plantation forest and grassland were the two main vegetation types used to mitigate soil and water loss after cultivation abandonment. The purpose of this study was to compare the soil carbon stock and flux of these two types of vegetation which restored for 25 years. The experiment was conducted in Yangjuangou catchment in Yan′an City, Shaanxi Province, China. Two adjacent slopes were chosen for this study. Six sample sites were spaced every 35–45 m from summit to toe slope along the hill slope, and each sample site contained three sampling plots. Soil organic carbon and related physicochemical properties in the surface soil layer(0–10 cm and 10–20 cm) were measured based on soil sampling and laboratory analysis, and the soil carbon dioxide(CO2) emissions and environmental factors were measured in the same sample sites simultaneously. Results indicated that in general, a higher soil carbon stock was found in the black locust plantation forest than that in grassland throughout the hill slope. Meanwhile, significant differences in the soil carbon stock were observed between these two vegetation types in the upper slope at soil depth 0–10 cm and lower slope at soil depth 10–20 cm. The average daily values of the soil CO2 emissions were 1.27 μmol/(m2·s) and 1.39 μmol/(m2·s) for forest and grassland, respectively. The soil carbon flux in forest covered areas was higher in spring and less variation was detected between different seasons, while the highest carbon flux was found in grassland in summer, which was about three times higher than that in autumn and spring. From the carbon sequestration point of view, black locust plantation forest on hill slopes might be better than grassland because of a higher soil carbon stock and lower carbon flux.  相似文献   
148.
The nitrogen (N) input and Spartina alterniflora invasion in the tidal marsh of the southeast of China are increasingly serious. To evaluate CH4 emissions in the tidal marsh as affected by the N inputs and S. alterniflora invasion, we measured CH4 emissions from plots with vegetated S. alterniflora and native Cyperus malaccensis, and fertilized with exogenous N at the rate of 0 (NO), 21 (N1) and 42 (N2) g N/(m2.yr), respectively, in the Shanyutan marsh in the Minjiang River estuary, the southeast of China. The average CH4 fluxes during the experiment in the C. malaccensis and S. alterniflora plots without N addition were 3.67 mg CHa/(m2.h) and 7.79 mg CH4/(m2-h), respectively, suggesting that the invasion of S. alterniflora into the Minjiang River estuary stimulated CH4 emission. Exogenous N had positive effects on CH4 fluxes both in native and in invaded tidal marsh. The mean CH4 fluxes of NI and N2 treat- ments increased by 31.05% and 123.50% in the C. malaccensis marsh, and 63.88% and 7.55% in the S. alterniflora marsh, respectively, compared to that of NO treatment. The CH4 fluxes in the two marshes were positively correlated with temperature and pH, and nega- tively correlated with electrical conductivity and redox potential (Eh) at different N addition treatments. While the relationships between CH4 fluxes and environmental variables (especially soil temperature, pH and Eh at different depths) tended to decrease with N additions. Significant temporal variability in CH4 fluxes were observed as the N was gradually added to the native and invaded marshes. In order to better assess the global climatic role of tidal marshes as affected by N addition, much more attention should be paid to the short-term temporal variability in CH4 emission.  相似文献   
149.
温室气体排放评价指标及其定量分析   总被引:20,自引:0,他引:20  
温室气体排放的科学定量评价是建立国际温室气体减排框架、确定各国合理的减排责任、部署国际减排行动的基础。通过系统阐述目前国际上通行的温室气体排放的主要评价指标(国别排放指标、人均排放指标、GDP 排放指标和国际贸易排放指标等), 并通过定量评价剖析这些评价指标的优缺点及其局限性。讨论了发展科学、公平和易于广泛接受的新评价指 标的可能性。基于可持续发展的公平性原则, 提出了“工业化累积人均排放量” 的新指标, 以客观定量评价世界各国工业化以来温室气体历史累积排放量的当代人均量。新指标的结果显示, 英美等老牌工业化国家的工业化累积人均排放量远高于全球平均水平和发展中国家的 水平。还提出并讨论了人均单位GDP 排放量、消费排放量、生存排放量等潜在的评价指标。  相似文献   
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