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A Review of Impacts of Climate Change on Birds:Implications of Long-term Studies 被引量:18
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作者 石建斌 李迪强 肖文发 《Zoological Research》 CAS CSCD 北大核心 2006年第6期637-646,共10页
It is generally accepted that climate has changed greatly on a global scale, and that the earth's climate has already wanned by some degrees over the past century. Ample evidence shows that there have been apparent c... It is generally accepted that climate has changed greatly on a global scale, and that the earth's climate has already wanned by some degrees over the past century. Ample evidence shows that there have been apparent changes in avian population dynamics, life-history traits and geographic ranges in response to global climate change. This paper briefly reviews the possible effects of climate change on avian biology and ecology all over the world, with emphasis on new findings from several long-term studies in Europe and North America, which provide unique opportunities to investigate how long-term changes in climate affect birds at both individual and population levels. The implications of such long-term studies for future bird studies in China is discussed with hope that this review can contribute to the preparation and plan for studies of climatic effects on birds in China in the future. 展开更多
关键词 Climate change Global wanning Geographic range Phenological change BIRDS
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Applications of seismic techniques to gas hydrates prediction 被引量:3
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作者 刘彦君 刘喜武 +2 位作者 刘大锰 王燕津 赵迎新 《Applied Geophysics》 SCIE CSCD 2008年第1期67-73,共7页
Based on the sensitivity of geophysical response to gas hydrates contained in sediments, we studied the prediction of gas hydrates with seismic techniques, including seismic attributes analysis, AVO, inverted velocity... Based on the sensitivity of geophysical response to gas hydrates contained in sediments, we studied the prediction of gas hydrates with seismic techniques, including seismic attributes analysis, AVO, inverted velocity field construction for dipping formations, and pseudo-well constrained impedance inversion. We used an optimal integration of geophysical techniques results in a set of reliable and effective workflows to predict gas hydrates. The results show that the integrated analysis of the combination of reflectivity amplitude, instantaneous phase, interval velocity, relative impedance, absolute impedance, and AVO intercept is a valid combination of techniques for identifying the BSR (Bottom Simulated Reflector) from the lower boundary of the gas hydrates. Integration of seismic sections, relative and absolute impedance sections, and interval velocity sections can improve the validity of gas hydrates determination. The combination of instantaneous frequency, energy half attenuation time, interval velocity, AVO intercept, AVO product, and AVO fluid factor accurately locates the escaped gas beneath the BSR. With these conclusions, the combined techniques have been used to successfully predict the gas hydrates in the Dongsha Sea area. 展开更多
关键词 Geophysical data special processing gas hydrates BSR prediction.
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Soil carbon dioxide fluxes of a typical broad-leaved/Korean pine mixed forest in Changbai Mountain, China 被引量:3
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作者 王琛瑞 吴劼 +1 位作者 梁战备 黄国宏 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期268-272,共5页
The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static clos... The forest ecosystem plays an important role in the global carbon cycling. A study was conducted to evaluate soil CO2 flux and its seasonal and diurnal variation with the air and soil temperatures by using static closed chamber technique in a typical broad-leaved/Korean pine mixed forest area on the northern slope of Changbai Mountain, Jilin Province, China. The experiment was carried out through the day and night in the growing season (from June to September) in situ and sample gas was analyzed by a gas chromatograph. Results showed that the forest floor was a large net source of carbon, and soil CO2 fluxes had an obvi-ous law of seasonal and diel variation. The soil CO2 flux of broad-leaved/Korean pine mixed forest was in the range of 0.302.42 mmol穖-2穝-1 with the mean value of 0.98 mmol穖-2穝-1. An examination on the seasonal pattern of soil CO2 emission suggested that the variability in soil CO2 flux could be correlated with variations in soil temperature, and the maximum of mean CO2 flux occurred in July ((1.27±23%) mmol穖-2穝-1) and the minimum was in September ((0.50±28%) mmol穖-2穝-1). The fluctuations in diel soil CO2 flux were also correlated with changes in soil temperature; however, there existed a factor for a time lag. Soil CO2 flux from the forest floor was strongly related to soil temperature and had the highest correlation with temperature at 6-cm depth of soil. Q10 values based on air temperature and soil temperature of different soil depths were at the ranges of 2.09–3.40. 展开更多
关键词 Soil CO2 flux Broad-leaved/Korean pine mixed forest Q10 value Changbai Mountain
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Morphology, photoluminescence and gas sensing of Ce-doped ZnO microspheres 被引量:1
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作者 李酽 刘金城 +2 位作者 连晓雪 吕谭 赵方贤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3657-3663,共7页
Ce-doped ZnO microspheres were solvothermally prepared, and their microstructure, morphology, photoluminescence, and gas sensing were investigated by X-ray diffractometer, field emission scanning electron microscopy, ... Ce-doped ZnO microspheres were solvothermally prepared, and their microstructure, morphology, photoluminescence, and gas sensing were investigated by X-ray diffractometer, field emission scanning electron microscopy, transmission electron microscopy, fluorescence spectrometer and gas sensing analysis system. The results showed that the Ce-doped ZnO microspheres were composed of numerous nanorods with a diameter of 70 nm and a wurtzite structure. Ce-doping could cause a morphological transition from loose nanorods assembly to a tightly assembly in the microspheres. Compared with pure ZnO, the photoluminescence of the Ce-doped microspheres showed red-shifted UV emission and an enhanced blue emission. Particularly, the Ce-doped ZnO sensors exhibited much higher sensitivity and selectivity to ethanol than that of pure ZnO sensor at 320 °C. The ZnO microspheres doped with 6% Ce (mole fraction) exhibited the highest sensitivity (about 30) with rapid response (2 s) and recovery time (16 s) to 50×10?6 ethanol gas. 展开更多
关键词 Ce-doping ZNO MORPHOLOGY MICROSPHERES gas sensing PHOTOLUMINESCENCE
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Advances of study on atmospheric methane oxidation (consumption) in forest soil 被引量:2
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作者 王琛瑞 史奕 +2 位作者 杨晓明 吴杰 岳进 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期230-238,共9页
Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink fo... Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink for atmospheric CH4 in terrestrial ecosystem. Many comparison studies proved that forest soil had the biggest capacity of oxidizing atmospheric CH4 in various unsaturated soils. However, up to now, there is not an overall review in the aspect of atmospheric CH4 oxidation (consumption) in forest soil. This paper analyzed advances of studies on the mechanism of atmospheric CH4 oxidation, and re-lated natural factors (Soil physical and chemical characters, temperature and moisture, ambient main greenhouse gases con-centrations, tree species, and forest fire) and anthropogenic factors (forest clear-cutting and thinning, fertilization, exogenous aluminum salts and atmospheric deposition, adding biocides, and switch of forest land use) in forest soils. It was believed that CH4 consumption rate by forest soil was limited by diffusion and sensitive to changes in water status and temperature of soil. CH4 oxidation was also particularly sensitive to soil C/N, Ambient CO2, CH4 and N2O concentrations, tree species and forest fire. In most cases, anthropogenic disturbances will decrease atmospheric CH4 oxidation, thus resulting in the elevating of atmos-pheric CH4. Finally, the author pointed out that our knowledge of atmospheric CH4 oxidation (consumption) in forest soil was insufficient. In order to evaluate the contribution of forest soils to atmospheric CH4 oxidation and the role of forest played in the process of global environmental change, and to forecast the trends of global warming exactly, more researchers need to studies further on CH4 oxidation in various forest soils of different areas. 展开更多
关键词 Atmospheric methane Oxidation Global warming Forest soil SINK
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当前我国科技发展的趋势(下)
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《科学学与科学技术管理》 CSSCI 北大核心 1999年第10期7-9,共3页
关键词 科技发展 气球化 中国 趋势
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Obsevation for Epidermal Ultrastructure of Nostoc sphaeroides Kutzing under Scanning Electron Microscope 被引量:1
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作者 李莉 《Agricultural Science & Technology》 CAS 2009年第1期1-3,共3页
[Objective]The experiment aimed to explore a new way for observing surface structure of Nostoc sphaeroides Kutzing. [Method] The scanning electron microscope was used to observe the epidermal ultrastructure of wild an... [Objective]The experiment aimed to explore a new way for observing surface structure of Nostoc sphaeroides Kutzing. [Method] The scanning electron microscope was used to observe the epidermal ultrastructure of wild and cultured Nostoc sphaeroides Kutzing. [ Result] The epidermis of wild and cultured Nostoc sphaeroides Kutzing showed mixture structure of fibril colloid which was reticular arranged. The difference between wild and cultured Nostoc sphaeroides Kutzing was that the outer epidermis of cultured Nostoc sphaeroides Kutzing had trichome distribution but the wild Nostoc sphaeroides Kutzing did not has such distribution. The obsevation results of under smaller than 10 μm by scanning electron microscope was touched thick and showed many folds and distortions. [ Conclusion] The scanning electron microscope was an effective way to study development of Nostoc sphaeroides Kutzing colony and it was worth popularizing. 展开更多
关键词 Nostoc sphaeroides Kutzing Epidermal ultrastructure Scanning electron microscope
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Emission and Fixation of CO_2 from Soil System as Influenced by Long-Term Application of Organic Manure in Paddy Soils 被引量:8
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作者 CHEN Yi WU Chun-yan SHUI Jian-guo WANG Jia-yu 《Agricultural Sciences in China》 CAS CSCD 2006年第6期456-461,共6页
The observations of 25-yr long-term experiment in Zhejiang paddy soils showed that the soil organic matter could increase continuously with applying organic manure, and the increase in rate enhanced along with the app... The observations of 25-yr long-term experiment in Zhejiang paddy soils showed that the soil organic matter could increase continuously with applying organic manure, and the increase in rate enhanced along with the application rates of organic manure. By mathematical modeling, the soil organic matter increased by 22 kg when 1 t of fresh FYM was applied. The CO2 emission resulting from the mineralization of soil organic matter increased with the increase in the application rate of the organic manure as well as the increase in the root residues. It is expected that the CO2 emission will be at 10.04-21.61 t ha-1 yr-1 when 16.5-49.5 t ha-1 yr-1 of fresh FYM is applied. The soil organic carbon from mineralization and release of applied organic carbon (fresh FYM and root residues) will affect the CO2 concentration in the atmosphere. So, the higher the application rate of organic manure, the more is the fixed organic carbon. The CO2 fixation will be at 1.885-3.463 t ha-1 yr-1 when 16.5-49.5 t ha-1 yr-1 of fresh FYM is applied. Thus, the CO2 fixation will increase by 46.7 kg by applying 1 t fresh FYM. To apply organic manure continuously in rice fields may reduce the contribution to the increase of CO2 concentration in the atmosphere. 展开更多
关键词 paddy soil organic manure carbon cycle carbon dioxide global climatic changes
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Microstructure evolution of Al_(0.6)CoCrFeNi high entropy alloy powder prepared by high pressure gas atomization 被引量:6
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作者 Shang-cheng ZHOU Peng ZHANG +6 位作者 Yun-fei XUE Fu-chi WANG Lu WANG Tang-qing CAO Zhen TAN Bao-ynan CHENG Ben-peng WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第5期939-945,共7页
The influence of cooling rate on the microstructure of Al0.6CoCrFeNi high entropy alloy(HEA) powders was investigated. The spherical HEA powders(D50≈78.65 μm) were prepared by high pressure gas atomization. The ... The influence of cooling rate on the microstructure of Al0.6CoCrFeNi high entropy alloy(HEA) powders was investigated. The spherical HEA powders(D50≈78.65 μm) were prepared by high pressure gas atomization. The different cooling rates were achieved by adjusting the powder diameter. Based on the solidification model, the relationship between the cooling rate and the powder diameter was developed. The FCC phase gradually disappears as particle size decreases. Further analysis reveals that the phase structure gradually changes from FCC+BCC dual-phase to a single BCC phase with the increase of the cooling rate. The microstructure evolves from planar crystal to equiaxed grain with the cooling rate increasing from 3.19×10^4 to 1.11×10^6 K/s. 展开更多
关键词 Al0.6CoCrFeNi high entropy alloy high pressure gas atomization spherical powder MICROSTRUCTURE cooling rate
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Impact of Regional Development on Carbon Emission: Empirical Evidence Across Countries 被引量:8
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作者 LI Guoping YUAN Yuan 《Chinese Geographical Science》 SCIE CSCD 2014年第5期499-510,共12页
Global warming is recently an urgent issue worldwide. The increase of carbon emissions induced by human economic activi- ties has become a major driving force behind global climate change. Thus, as a matter of social ... Global warming is recently an urgent issue worldwide. The increase of carbon emissions induced by human economic activi- ties has become a major driving force behind global climate change. Thus, as a matter of social responsibility, reasonable carbon con- straints should be implemented to ensure environmental security and sustainable development for every country. Based on a summary of studies that examined the relationship between carbon emissions and regional development, this paper shows that human activity-led carbon emission is caused by the combination of several influencing factors, including population size, income level, and technical pro- gress. Thus, a quantitative model derived from IPAT-ImPACT-Kaya series and STIRPAT models was established. Empirical analysis using multivariate nonlinear regression demonstrated that the origins of growing global carbon emission included the increasing influ- encing elasticity of the population size and the declining negative effect of technical progress. Meanwhile, in context of classification of country groups at different income levels, according to the comparison of fluctuating patterns of the influencing elasticity, technical progress was found as the main factor influencing carbon emission levels in high-income countries, and population size might he the controlling factor in middle-income countries. However, for low-income countries, the nonlinear relationship between carbon emission and its influencing factors was not significant, whereas population growth was identified as an important potential driving force in future carbon emissions. This study can therefore provide a reference for the formulation of policies on carbon constraints, especially to de- velop more efficient carbon mitigating policies for countries at different income levels. 展开更多
关键词 carbon emission regional development population size income level technical progress
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Contentious Petroleum Geochemical Issues in China’s Sedimentary Basins 被引量:5
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作者 黎茂稳 庞雄奇 《Petroleum Science》 SCIE CAS CSCD 2004年第3期4-22,40,共20页
Petroleum geochemistry contributes to exploration successes by providing key constraints for geological models and critical input to exploration scenarios. One of the most important tasks in a typical exploration pr... Petroleum geochemistry contributes to exploration successes by providing key constraints for geological models and critical input to exploration scenarios. One of the most important tasks in a typical exploration program is to identify the most effective source intervals or kitchens in a basin, through oil-source correlation. The results of correlation are valid only if the geochemical parameters used address adequately the genetic characteristics of the source rocks as well as the mass transport and mixing processes of hydrocarbon fluids occurring in the carrier beds and reservoirs. This manuscript discusses four of the major contentious petroleum geochemical issues in China’s sedimentary basins. It is suggested that marine incursions played a significant role in the formation of prolific petroleum source rocks in the gigantic, dominantly freshwater, Songliao Basin. Several models are proposed to account for the occurrence of immature oils in the Cathaysian rift system including the Bohai Bay Basin, thus immature source rocks are considered a mere minor contributor to the known economic immature oil resources. Both geological and geochemical evidence are reviewed to refute a dominantly coaly source for the petroleum discovered in the Turpan Basin. Results of case studies are presented to demonstrate the importance of recognizing petroleum fluid mixing to solve the oil-source correlation issues in the structurally complex Tarim Basin. In addressing the fundamental assumptions and potential flaws of the molecular geochemical parameters commonly used for oil-source correlation, the need of a mass fraction approach is proposed to deal with such contentious issues as marine versus lacustrine, coal versus lacustrine, and mature versus immature oils. 展开更多
关键词 Oil-source correlation immature oil coal-derived oil oil-gas mixed sources Songliao Basin Bohai Bay Basin Tuha Basin Tarim Basin
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Effect of Climate Variability and Human Activities on Runoff in the Jinghe River Basin, Northwest China 被引量:4
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作者 YAO Jun-qiang ZHAO Qiu-dong LIU Zhi-hui 《Journal of Mountain Science》 SCIE CSCD 2015年第2期358-367,共10页
Much attention has recently been focused on the effects of climate variability and human activities on the runoff. In this study, we analyzed 56-yr(1957–2012) runoff change and patterns in the Jinghe River Basin(JRB)... Much attention has recently been focused on the effects of climate variability and human activities on the runoff. In this study, we analyzed 56-yr(1957–2012) runoff change and patterns in the Jinghe River Basin(JRB) in the arid region of northwest China. The nonparametric Mann–Kendall test and the precipitation-runoff double cumulative curve(PRDCC) were used to identify change trend and abrupt change points in the annual runoff. It was found that the runoff in the JRB has periodically fluctuated in the past 56 yr. Abrupt change point in annual runoff was identified in the JRB, which occurred in the years around 1964 and 1996 dividing the long-term hydrologic series into a natural period(1957 – 1964) and a climate and man-induced period(1965 – 1996 and 1997 – 2012). In the 1965 – 1996 period, human activities were the main factor that decreased runoff with contribution of 88.9%, while climate variability only accounted for 11.1%. However,the impact of climate variability has been increased from 11.1% to 47.5% during 1997 – 2012, showing that runoff in JRB is more sensitive to climate variability during global warming. This study distinguishes theeffect of climate variability from human activities on runoff, which can do duty for a reference for regional water resources assessment and management. 展开更多
关键词 Water resource RUNOFF Climate variability Precipitation Jinghe River Basin
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Detecting Global Vegetation Changes Using Mann-Kendal(MK) Trend Test for 1982–2015 Time Period 被引量:9
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作者 GUO Meng LI Jing +2 位作者 HE Hongshi XU Jiawei JIN Yinghua 《Chinese Geographical Science》 SCIE CSCD 2018年第6期907-919,共13页
Vegetation is the main component of the terrestrial ecosystem and plays a key role in global climate change. Remotely sensed vegetation indices are widely used to detect vegetation trends at large scales. To understan... Vegetation is the main component of the terrestrial ecosystem and plays a key role in global climate change. Remotely sensed vegetation indices are widely used to detect vegetation trends at large scales. To understand the trends of vegetation cover, this research examined the spatial-temporal trends of global vegetation by employing the normalized difference vegetation index(NDVI) from the Advanced Very High Resolution Radiometer(AVHRR) Global Inventory Modeling and Mapping Studies(GIMMS) time series(1982–2015). Ten samples were selected to test the temporal trend of NDVI, and the results show that in arid and semi-arid regions, NDVI showed a deceasing trend, while it showed a growing trend in other regions. Mann-Kendal(MK) trend test results indicate that 83.37% of NDVI pixels exhibited positive trends and that only 16.63% showed negative trends(P < 0.05) during the period from 1982 to 2015. The increasing NDVI trends primarily occurred in tree-covered regions because of forest growth and re-growth and also because of vegetation succession after a forest disturbance. The increasing trend of the NDVI in cropland regions was primarily because of the increasing cropland area and the improvement in planting techniques. This research describes the spatial vegetation trends at a global scale over the past 30+ years, especially for different land cover types. 展开更多
关键词 vegetation trend NDVI3g.v1 Mann-Kendall (MK) trend test land cover types
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Detection of spatial hot spots and variation for the neon flying squid Ommastrephes bartramii resources in the northwest Pacific Ocean 被引量:6
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作者 冯永玖 陈新军 刘艳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期921-935,共15页
With the increasing effects of global climate change and fishing activities,the spatial distribution of the neon flying squid(Ommastrephes bartramii) is changing in the traditional fishing ground of 150°-160°... With the increasing effects of global climate change and fishing activities,the spatial distribution of the neon flying squid(Ommastrephes bartramii) is changing in the traditional fishing ground of 150°-160°E and 38°-45°N in the northwest Pacific Ocean.This research aims to identify the spatial hot and cold spots(i.e.spatial clusters) of O.bartramii to reveal its spatial structure using commercial fishery data from2007 to 2010 collected by Chinese mainland squid-j igging fleets.A relatively strongly-clustered distribution for O.bartramii was observed using an exploratory spatial data analysis(ESDA) method.The results show two hot spots and one cold spot in 2007 while only one hot and one cold spots were identified each year from2008 to 2010.The hot and cold spots in 2007 occupied 8.2%and 5.6%of the study area,respectively;these percentages for hot and cold spot areas were 5.8%and 3.1%in 2008,10.2%and 2.9%in 2009,and 16.4%and 11.9%in 2010,respectively.Nearly half(>45%) of the squid from 2007 to 2009 reported by Chinese fleets were caught in hot spot areas while this percentage reached its peak at 68.8%in 2010,indicating that the hot spot areas are central fishing grounds.A further change analysis shows the area centered at156°E/43.5°N was persistent as a hot spot over the whole period from 2007 to 2010.Furthermore,the hot spots were mainly identified in areas with sea surface temperature(SST) in the range of 15-20℃ around warm Kuroshio Currents as well as with the chlorophyll-a(chl-a) concentration above 0.3 mg/m^3.The outcome of this research improves our understanding of spatiotemporal hotspots and its variation for O.bartramii and is useful for sustainable exploitation,assessment,and management of this squid. 展开更多
关键词 Ommastrephes bartramii exploratory spatial data analysis (ESDA) spatial hot spot spatialautocorrelation variation assessment northwest Pacific Ocean
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Early warning for geo-hazards based on the weather condition in China 被引量:11
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作者 Chuanzheng LIU Yanhui LIU Mingsheng WEN Can TANG Tiefeng LI Jianfa LIAN 《Global Geology》 2006年第2期131-137,共7页
According to national early warning practice for geo-hazards from 2003 to 2005,it is systematically concluded that the basic characteristics of geo-hazards,early warning method and forecast result based on the geologi... According to national early warning practice for geo-hazards from 2003 to 2005,it is systematically concluded that the basic characteristics of geo-hazards,early warning method and forecast result based on the geological maps of China in a scale 1∶6 000 000.With the contrast of different characters between sustained rainfall and typhoon rainfall inducing geo-hazards,the disaster reduction result and some problems are preliminarily analyzed.Some basic recognition is that early warning to geo-hazards is feasible,national scale forecast is only to call attention,but can't immediately be used to disaster reduction decision-making.And,the future direction is to build a united disaster reduction framework of early warning system including national,provincial and county levels based on weather factors in different scale of area. 展开更多
关键词 China geo-hazards early warning based on weather condition result analysis
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The gap report of global climate change mitigation, finance, and governance after the United States declared its withdrawal from the Paris Agreement 被引量:4
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作者 Qimin Chai Sha Fu +2 位作者 Huaqing Xu Weiran Li Yan Zhong 《Chinese Journal of Population,Resources and Environment》 2017年第3期196-208,共13页
On 1 June 2017, the US President Donald Trump officially announced the withdrawal from the Paris Agreement, thus the study on the reasons of withdrawal, the potential impacts, and coping strategies has become a focus ... On 1 June 2017, the US President Donald Trump officially announced the withdrawal from the Paris Agreement, thus the study on the reasons of withdrawal, the potential impacts, and coping strategies has become a focus among policy circles and of the international community. Based on the self-developed US Policy Assessment Model, this paper systematically evaluates the three potential "major deficits" in terms of mitigation, climate finance, and global climate governance, as a result of the US withdrawal from the Paris Agreement and puts forward policy suggestions for coping with such transformations accordingly. The study shows that the United States 'withdrawal from the Paris Agreement will affect the existence and implementation of successive climate policies and result in an additional 8.8-13.4% increase in the global emissions reduction deficit. The United States' withdrawal will also deteriorate the existing climate finance mechanism. The Green Climate Fund (GCF)'s funding gap will increase by USS2 billion, while the gap of long-term climate finance will increase by about USS5 billion a year. Either the China-EU or the "BASIC plus" mechanism could fill the governance deficit caused by the United States and the lack of political momentum may continue for a while in the future. 展开更多
关键词 Trump administration Paris Agreement mitigationdeficit finance deficit global climate governance deficit
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Global Trend of Low-carbon Economy and China's Responses 被引量:1
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作者 He Jiankun Zhou Jian +1 位作者 Liu Bin Sun Zhenqing 《Chinese Journal of Population,Resources and Environment》 2011年第2期3-17,共15页
Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crise... Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the global trend of low-carbon economy on China can not be overlooked,and it is both a challenge and an opportunity for China's future development.Based on comparative studies on the low-carbon economy of China,the U.S.,EU and Japan,the authors conclude that China should blaze a new path of lowcarbon economy development with Chinese characteristics,and the authors have put forward relevant countermeasures for China to address the global trend of low-carbon economy from angles of countries,enterprises and the public 展开更多
关键词 global trend of low-carbon economy Green NewDeal low-carbon development economic development address-ing global climate change
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Effect of Aspect on Climate Variation in Mountain Ranges of Shennongjia Massif, Central China 被引量:1
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作者 ZHANG Yi 《Chinese Geographical Science》 SCIE CSCD 2018年第1期74-85,共12页
The aim of this study was to better understand the mechanisms of regional climate variation in mountain ranges with contrasting aspects as mediated by changes in global climate. It may help predict trends of vegetatio... The aim of this study was to better understand the mechanisms of regional climate variation in mountain ranges with contrasting aspects as mediated by changes in global climate. It may help predict trends of vegetation variations in native ecosystems in natural reserves. As measures of climate response, temperature and precipitation data from the north, east, and south-facing mountain ranges of Shennongjia Massif in the coldest and hottest months(January and July), different seasons(spring, summer, autumn, and winter) and each year were analyzed from a long-term dataset(1960 to 2003) to tested variations characteristics, temporal and spatial quantitative relationships of climates. The results showed that the average seasonal temperatures and precipitation in the north, east, and south aspects of the mountain ranges changed at different rates. The average seasonal temperatures change rate ranges in the north, east, and south-facing mountain ranges were from –0.0210℃/yr to 0.0143℃/yr, –0.0166℃/yr to 0.0311℃/yr, and –0.0290 ℃/yr to 0.0084℃/yr, respectively, and seasonal precipitation variation magnitude were from –1.4940 mm/yr to 0.6217 mm/yr, –1.6833 mm/yr to 2.6182 mm/yr, and –0.8567 mm/yr to 1.4077 mm/yr, respectively. The climates variation trend among the three mountain ranges were different in magnitude and direction, showing a complicated change of the climates in mountain ranges and some inconsistency with general trends in global climate change. The climate variations were significantly different and positively correlated cross mountain ranges, revealing that aspects significantly affected on climate variations and these variations resulted from a larger air circulation system, which were sensitive to global climate change. We conclude that location and terrain of aspect are the main factors affecting differences in climate variation among the mountain ranges with contrasting aspects. 展开更多
关键词 regional climate variation slope aspect Shennongjia Massif One-way ANOVA global climate change
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Spatial and Quantitative Comparison of Satellite-Derived Land Cover Products over China 被引量:5
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作者 GAO Hao JIA Gen-Suo 《Atmospheric and Oceanic Science Letters》 2012年第5期426-434,共9页
Because land cover plays an important role in global climate change studies, assessing the agreement among different land cover products is critical. Significant discrepancies have been reported among satellite-derive... Because land cover plays an important role in global climate change studies, assessing the agreement among different land cover products is critical. Significant discrepancies have been reported among satellite-derived land cover products, especially at the regional scale. Dif- ferent classification schemes are a key obstacle to the comparison of products and are considered the main fac- tor behind the disagreement among the different products. Using a feature-based overlap metric, we investigated the degree of spatial agreement and quantified the overall and class-specific agreement among the Moderate Resolution Imaging Spectoradiometer (MODIS), Global Land Cover 2000 (GLC2000), and the National Land Cover/Use Data- sets (NLCD) products, and the author assessed the prod- ucts by ground reference data at the regional scale over China. The areas with a low degree of agreement mostly occurred in heterogeneous terrain and transition zones, while the areas with a high degree of agreement occurred in major plains and areas with homogeneous vegetation. The overall agreement of the MODIS and GLC2000 products was 50.8% and 52.9%, and the overall accuracy was 50.3% and 41.9%, respectively. Class-specific agree- ment or accuracy varied significantly. The high-agreement classes are water, grassland, cropland, snow and ice, and bare areas, whereas classes with low agreement are shru- bland and wetland in both MODIS and GLC2000. These characteristics of spatial patterns and quantitative agree- ment could be partly explained by the complex landscapes, mixed vegetation, low separability of spectro-temporal- texture signals, and coarse pixels. The differences of class definition among different the classification schemes also affects the agreement. Each product had its advantages and limitations, but neither the overall accuracy nor the class-specific accuracy could meet the requirements of climate modeling. 展开更多
关键词 land cover COMPARISON spatial pattern quantitative agreement
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Impact of Climatic Change on Agricultural Production and Response Strategies in China 被引量:1
20
作者 Liu Yansui Liu Yu Guo Liying 《Chinese Journal of Population,Resources and Environment》 2011年第4期16-23,共8页
A number of studies indicate that global climate warming has been increasing, especially in recent decades. Climate warming greatly affects global agro-production and food security-- becoming a hotspot of global envir... A number of studies indicate that global climate warming has been increasing, especially in recent decades. Climate warming greatly affects global agro-production and food security-- becoming a hotspot of global environmental change. This paper proposes a structural and orientational framework for scientifically addressing climatic change impact on agroroduction. Through literature reviews and comparative studies, the paper systematically summarizes influencing mechanisms and impact of climate warming on such agro-production factors as light, temperature, soil quality and water environment. The impact of climate warm- ing on cultivation regions, cropping systems, crop pests, agro- production capacity, agro-economy and farm management is analyzed. Then, suitable climate-adapting agro-development strategies are put forward for different regions in China. The strategies are carefully selected from a repository of international tested climatic change countermeasures in agriculture at national or district level. 展开更多
关键词 agro-production food security climatic change response strategy China
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