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21.
Quantitative analysis of the impact factors of conventional energy carbon emissions in Kazakhstan based on LMDI decomposition and STIRPAT model 总被引:2,自引:2,他引:0
Quantitative analysis of the impact factors in energy-related CO2 emissions serves as an important guide for reducing carbon emissions and building an environmentally-friendly society. This paper aims to use LMDI method and a modified STIRPAT model to research the conventional energy-related CO2 emissions in Kazakhstan after the collapse of the Soviet Union. The results show that the trajectory of CO2 emissions displayed U-shaped curve from 1992 to 2013. Based on the extended Kaya identity and additive LMDI method, we decomposed total CO2 emissions into four influencing factors. Of those, the economic active effect is the most influential factor driving CO2 emissions, which produced 110.86 Mt CO2 emissions, with a contribution rate of 43.92%. The second driving factor is the population effect, which led to 11.87 Mt CO2 emissions with a contribution rate of 4.7%. On the contrary, the energy intensity effect is the most inhibiting factor, which caused–110.90 Mt CO2 emissions with a contribution rate of–43.94%, followed by the energy carbon structure effect resulting in–18.76 Mt CO2 emissions with a contribution rate of–7.43%. In order to provide an in-depth examination of the change response between energy-related CO2 emissions and each impact factor, we construct a modified STIRPAT model based on ridge regression estimation. The results indicate that for every 1% increase in population size, economic activity, energy intensity and energy carbon structure, there is a subsequent increase in CO2 emissions of 3.13%, 0.41%, 0.30% and 0.63%, respectively. 相似文献
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23.
Stable isotopes of water have been widely used in understanding the hydrological functions of alpine inland catchments. This study identifies dominant runoff generation mechanisms based on isotopic data (δ18O and δ2H) of 487 rainwater and river-water samples from three tributaries in the Tarim River Basin in China for the period May–September 2013. The isotope hydrograph separation results provide a comprehensive overview of the rainfall influence on hydrological processes. Stream water and groundwater have varied responses to different intensities of rainfall events. Only a small proportion of rainfall is directly transported to the stream during such events. An inconsistent temporal trend of event water contribution is observed in the three catchments. The average fractional contributions of rainfall for the Tizinafu, Kumalak and Huangshuigou rivers are 10.3% (±1.1%), 9.7% (±2.9%) and 8.7% (±2.4%), respectively. 相似文献
24.
巴西马托格罗索州阿尔塔·弗洛雷斯塔(Alta Floresta)地区是亚马孙盆地西南部重要的金成矿省。为了满足中资矿业公司进行矿业投资和开发活动的需求,在实地考察和文献资料搜集的基础上,对该地区金矿地质特征和矿床类型进行了初步总结。该区主要的金矿类型有石英脉型、花岗斑岩型、红土型金矿等,其中石英脉型和红土型金矿为主要的金矿开发类型。区域构造对岩浆作用、金矿化作用和矿床类型等具有重要控制作用。总体来说,该地区具有多次金成矿活动,金成矿类型丰富,可作为中资矿业公司实施"走出去"战略的重要成矿区带。 相似文献
25.
Ruifeng Zhao Yaning Chen Huarong Zhou Yiqing Li Yibing Qian Lihua Zhang 《Environmental Geology》2009,57(2):455-464
The wetlands in the middle and lower reaches of the Tarim River are a rich area of biodiversity and natural resources in the
inland arid region of China. However, this wetland area has decreased in size during the past several decades. Water quality
and biodiversity has declined due to expanded agricultural activities since 1960s. Using remote sensing (RS), geographic information
system (GIS) and global positioning system (GPS) techniques, we investigated the dynamics, spatial patterns and fragmentation
of the wetlands in the middle and lower reaches of the Tarim River from 1980 to 2000. We found that the total area of the
wetlands was reduced by 45.8% and the density of the patches increased four times from 1980 to 1990. From 1990 to 2000, though
the total area of the wetlands slightly increased the number of the patches increased three times and the density of the patches
doubled. Based on the analyses of transition matrixes, diversity and fragmentation indexes, and spatial distribution alternation
of the wetlands, we found the landscape diversity and fragmentation indices increased while wetland dominance index decreased
dramatically. Among the wetland types, the areas of the river-channel, reservoir and pond wetlands increased while the areas
of the lake and marsh wetlands decreased continuously. 相似文献
26.
In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation.The results from TWINSPAN and DCCA showed that:1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region,the basic patterns characteristic of the different habitats are due to topographic factors,nutrients and moisture conditions;2) The elevation affected the most basic differentiation of plant communities in the study area,indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area;3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities;4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities.In summary,under complicated mountainous topographic conditions,the habitat conditions for the communities differed very significantly,and the combination of elevation,soil moisture content,total nitrogen,slope aspect,and pH value influenced and controlled the formation of community distribution patterns in the study area. 相似文献
27.
塔里木河干流径流损耗及其人类活动影响强度变化 总被引:6,自引:1,他引:5
依据塔里木河干流1957-2008 年的年径流量监测数据,计算出干流年径流损耗量,利用线性回归法,对干流年径流损耗量时间序列变化趋势进行分析,建立影响径流损耗的社会经济指标体系,运用层次分析法和权重加权法剖析人类活动影响强度变化趋势,并探讨人为径流损耗的主要原因。研究结果表明:① 近50 多年来,塔河干流年径流损耗量表现出递减变化趋势,但上、中、下游存在差异,上游增加显著,增速约为2.09×108 m3/10a,而中、下游递减趋势显著,减速分别为1.61×108 m3/10a 和2.30×108 m3/10a;② 干流来水量与径流损耗量之间呈明显的正相关,R2 = 0.9996,可认为来水量减少是诱发径流损耗量减少的直接原因;③ 人类活动强度指数与人为径流损耗量之间亦呈显著的正相关,R2 = 0.9822,说明自20 世纪70 年代中期开始,随着人类活动强度的逐渐增大,人类活动对径流损耗的干扰就处于一个扩大和加重的过程;④ 人口增长、产业结构调整、居民对物质经济的追求等社会经济活动是引起人为径流损耗量增加的主要原因。 相似文献
28.
SUN Huilan CHEN Yaning LI Weihong LI Feng CHEN Yapeng HAO Xingming YANG Yuhui 《地理学报》2010,20(5):652-666
In this paper, the monthly precipitation and temperature data collected at 7 stations in the Ili River Basin from 1961 to 2007 were analyzed by means of simple regression analysis, running mean, db6 wavelet function and Mann-Kendall test. This study revealed the characteristics of climate change and abrupt change points of precipitation and temperature during different time scales in the Ili River Basin within the past 50 years. The results showed that the precipitation increased from the mid-1980s until 2000 and has continued to increase at a smaller magnitude since 2000. Over the studied period, the precipitation increased significantly during the summer and winter months. The temperature increased greatly in the late 1980s, and has continued to show an increasing trend from the year 2000 to present. The temperature increases were most significant during the summer, autumn and winter months. In terms of different geographies, the temperature increase was significant during the winter in the plains and hilly regions; the increase was also significant during autumn in the intermontane basins. The climate change trends in the Ili River Basin were consistent with the changing trends of the North Atlantic Oscillation and the plateau monsoon. 相似文献
29.
塔里木河下游植被生态需水量(英文) 总被引:4,自引:0,他引:4
We have appraised the relationships between soil moisture,groundwater depth, and plant species diversity in the lower reaches of the Tarim River in western China,by analyzing field data from 25 monitoring wells across eight study sites and 25 permanent vegetation survey plots.It is noted that groundwater depth,soil moisture and plant species diversity are closely related.It has been proven that the critical phreatic water depth is five meters in the lower reaches of the Tarim River.We acquired the mean phreatic evaporation of different groundwater levels every month by averaging the two results of phreatic evaporation using the Qunk and Averyanov formulas.Based on different vegetation types and acreage with different groundwater depth,the total ecological water demand(EWD)of natural vegetation in 2005 was 2.4×108m 3in the lower reaches of the Tarim River.Analyzing the monthly EWD,we found that the EWD in the growth season(from April to September)is 81%of the year's total EWD.The EWD in May,June and July was 47%of the year's total EWD,which indicates the best time for dispensing artificial water.This research aims at realizing the sustainable development of water resources and provides a scientific basis for water resource management and sound collocation of the Tarim River Basin. 相似文献
30.
Impacts of climatic change on river runoff in northern Xinjiang of China over last fifty years 总被引:4,自引:2,他引:2
The characteristics of climatic change and river runoff, as well as the response of river runoff to climatic change in the northern Xinjiang are analyzed on the basis of the hydrological and meteorological data over the last 50 years by the methods of Mann-Kendall nonparametric test and the nonlinear regression model. The results show that: 1) The temperature and the precipitation increased significantly in the whole northern Xinjiang, but the precipitation displayed no obvious change, or even a decreasing trend in the northern mountainous area of the northern Xinjiang. 2) River runoff varied in different regions in the northern Xinjiang. It significantly increased in the northern slope of the Tianshan Mountains and the north of the northern Xinjiang (p=0.05), while slightly increased in the west of the northern Xinjiang. 3) North Atlantic Oscillation (NAO) affects river runoff by influencing temperature and precipita-tion. The NAO and precipitation had apparent significant correlations with the river runoff, but the temperature did not in the northern Xinjiang. Since the mid-1990s river runoff increase was mainly caused by the increasing temperature in the northern slope of the Tianshan Mountains and the north of the northern Xinjiang. Increased precipitation resulted in increased river runoff in the west of the northern Xinjiang. 相似文献