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1.
l introduCtionJiangsu Province is one of the fastest growing provinces in Cab and has eXPerienced aStonishingeconomic development since the Anplementahon of reform and open dOOr POlicy in 1978. As theeconomic development is closely related to the industrial develOPment, this Paper will examine tileperformance of industrial sector in Jiangsu in the period 1978-1995. ms may be helpfiil to understandthe regional economic development in the ProVince which serves as a good case study of this …  相似文献   

2.
Based on the statistical method and the historical evolution of meteorological stations,the temperature time series for each station in Hunan Province during 1910–2014 are tested for their homogeneity and then corrected.The missing data caused by war and other reasons at the 8 meteorological stations which had records before 1950 is filled by interpolation using adjacent observations,and complete temperature time series since the establishment of stations are constructed.After that,according to the representative analysis of each station in different time periods,the temperature series of Hunan Province during 1910–2014 are built and their changes are analyzed.The results indicate that the annual mean temperature has a significant warming trend during 1910–2014 and the seasonal mean temperature has the largest rising amplitude in winter and spring,followed by autumn,but no significant change in summer.Temperature variation over Hunan Province has several significant warm-cold alternations and more frequent than that in whole China.Annual and seasonal mean temperatures except summer and autumn have abrupt warming changes in the recent 100 years.The wavelet analysis suggests that the annual and four seasonal mean temperatures in recent 100 years have experienced two climatic shifts from cold to warm.  相似文献   

3.
Two typical provincial capitals (Nanjing and Zhengzhou) and two counties (Rugao and Yuanyang) in east (Jiangsu Province) and central (Henan Province) China were chosen respectively as the developed and less developed comparative cases for pedodiversity and land use diversity correlative analysis by borrowing the recently better developed pedodiversity methodology. Land use classification was worked out using remote sensing images in three different periods (1986-1988, 2000-2001 and 2004-2006) for these studied case areas before the calculation of the constituent diversity index and spatial distribution diversity index modified after Shannon entropy in 2 km×2 km grid scale of the soil and land use pattern were conducted and then a connection index was proposed to evaluate the relationship between soil and land use diversity. Results show that during the years from 1986 to 2006, the composition and spatial distribution of regional land use pattern had changed greatly. The agricultural land area of all the studied case areas decreased obviously in which Nanjing has the highest decrement of 895.98 km 2 mainly into urban use while the other land use type area changes show the same trend. The connection index of four typical soil family types and typical urban land use types, i.e., urban construction land, transportation land and industrial and mining area all increased in this period. In the studied case areas, there is the highest soil constituent diversity in Zhengzhou at 0.779 while the simplest soil constituent diversity in Rugao at 0.582. Meanwhile we have higher land use diversity in the more urbanized Jiangsu Province than Henan Province, Nanjing is ranking the first that has been getting higher and higher in the three periods at 0.366 in 1986-1988, 0.483 in 2000-2001 and 0.545 in 2004-2006. Finally, the connection index figures to evaluate the relationship between soil and land use diversity of the studied areas were compared to show the similar phenomenon that this figure grows fastest in Nanjing followed by Zhengzhou and other places.  相似文献   

4.
Land cover is the most evident landscape signal to characterize the influence of human activities on terrestrial ecosystems.Since the industrial revolution,the expansion of construction land has profoundly changed the status of land use coverage and changes.This study is proposed to reconstruct the spatial pattern of construction land(urban construction land and rural settlement land)for five historical periods over the past 200 years in Jiangsu Province with 200 m′200 m grids on the basis of quantitative estimation.Urban construction land is estimated based on data about city walls,four gates along walls,and other socio-economic factors.Rural settlement land is calculated based on the rural population and per capita housing allowance.The spatial pattern of historical construction land is simulated based on the distribution of modern construction land in 1985 with a quantitative-boundarysuitability control method and thorough consideration over connectivity of different land use types.The study concludes that:(1)the amount of construction land in Jiangsu Province is estimated at 963.46 km~2 in 1820,1043.46 km~2 in 1911,1672.40 km~2 in 1936,1980.34 km~2 in1952 and 10,687.20 km~2 in 1985;and(2)the spatial distribution of construction land features the great proclivity to water bodies and main roads and the strong polarization of existent residence.The results are verified directly and indirectly by applying the trend verification of construction land changes and patterns,the correlation analysis between rural settlement land and local arable land,and quantitative accuracy test of the reconstructed construction land to actual historical survey maps covering four sample regions in 1936.  相似文献   

5.
2007 Annual Meeting of the Geographical Society of China (GSC) was held on November 2-4 in Nanjing, Jiangsu Province of East China. A total of over 1300 geographical researchers and educators from 190 geographical institutions across the country participated in this meeting. More than 800 papers were submitted and discussed during this academic meeting. This meeting was co-sponsored by the GSC, Nanjing Normal University, Nanjing Institute of Geography and Limnology under the Chinese Academy of Sciences (CAS), Nanjing University, and Institute of Geographic Sciences and Natural Resources Research (IGSNRR) under the CAS.  相似文献   

6.
Based on the MODIS NDVI data and Landsat TM/ETM data of 2002 and 2012, this paper extracts the planting area of winter wheat–summer maize, single spring maize, cotton and forest/fruit trees, vegetable and paddy, and made the agricultural land use map of the North China Plain(NCP). Agricultural land use area accounted for 63.32% compared to the total area of the NCP in 2002. And it increased to 65.66% in 2012, which mainly caused by the vegetables and forest/fruit trees increasing. Planting areas of winter wheat–summer maize, cotton, single spring maize, forest/fruit trees, vegetables and paddy were 5031.21×10~3, 865.90×10~3, 1226.10×10~3, 1271.17×10~3, 648.02×10~3, 216.51×10~3 ha in 2012. Rank of changes was: vegetables(+45%) forest/fruit trees(+27.4%) paddy(–23.7%) cotton(–20.4%) single spring maize(+17.3%) winter wheat–summer maize(–0.6%). In developed region like Beijing and Tianjin, planting area of crops with high economic benefit(such as fruit trees and vegetables) increased significantly. Government policies for groundwater protection caused obvious decline of winter wheat cultivation in Hebei Province. Cotton planting in Shandong Province decreased more than 200,000 ha during 2002–2012. The data products will be published in the website: http://hydro.sjziam.ac.cn/Default.aspx. To clarify the agricultural land use in the NCP will be very helpful for the regional agricultural water consumption research, which is the serious problem in the NCP.  相似文献   

7.
Climate change is one of the most important factors that affect vegetation distribution in North China. Among all climatic factors, drought is considered to have the most significant effect on the environment. Based on previous studies, the climate drought index can be used to assess the evolutionary trend of the ecological environment under various arid climatic conditions. It is necessary for us to further explore the relationship between vegetation coverage(index) and climate drought conditions. Therefore, in this study, based on MODIS-NDVI products and meteorological observation data, the Palmer Drought Severity Index(PDSI) and vegetation coverage in North China were first calculated. Then, the interannual variations of PDSI and vegetation coverage during 2001–2013 were analyzed using a Theil-Sen slope estimator. Finally, an ecoregion perspective of the correlation between them was discussed. The experimental results demonstrated that the PDSI index and vegetation coverage value varied over different ecoregions. During the period 2001–2013, vegetation coverage increased in the southern and northern mountains of North China, while it showed a decreasing trend in the Beijing-Tianjin-Tangshan City Circle area and suburban agricultural zone located in Hebei Province and Henan Province). Over 13 years, the climate of the northeastern part of North China became more humid, while in the southern part of North China, it tended to be dry. According to the correlation analysis results, 73.37% of North China showed a positive correlation between the vegetation coverage and climate drought index. A negative correlation was observed mainly in urban and suburban areas of Beijing, Tianjin, Hebei Province, and Henan Province. In most parts of North China, drought conditions in summer and autumn had a strong influence on vegetation coverage.  相似文献   

8.
Soil water repellency (SWR) is one of the most important physical properties of soils found all over the world, and it may have significant effects on the eco-hydrological processes of land ecosystems. In this study, the Capillary Rise Method was used to measure the SWR in the artificial vegetation area in Shapotou, located in the southeast area of the Tengger Desert, Ningxia Province of western China. The variation of the soil water repellency among different minor topographies, different depths and different particle sizes was analyzed. The results of the study indicate that the SWR shows distinct changes with vegetation restoration, and it increases with an increase in the period of dune stabilization. In the same vegetation area, the SWR of soils in inter-dune depressions or windward slopes is slightly greater than that in crest or leeward slopes. The SWR of 0–3 cm topsoil is significantly greater than that in the 3–6 cm soil layer. The SWR decreases with an increase in grain size and the differences among the SWRs of different sieved soil fractions are found to be significant. There is also a significantly positive correlation between the SWR and the proportion of soils with grain sizes of 0–0.05, 0.05–0.01 and 0.01–0.15 mm, and a significantly negative correlation between the SWR and the propotion of soils with grain sizes exceeding 0.15 mm. The increase of SWR in revegetation areas may depend on the continuous depositing of atmospheric dust on the stabilized dune surface as well as the formation of biological soil crusts, especially on the formation of algal and lichen crusts. Enhanced SWR influences the effectiveness of water use of sand plants inhabiting the sand dunes.  相似文献   

9.
Rapeseed is one of the major oil crops in China and it is very sensitive to climate change.The Yangtze River Basin is the main rapeseed production area in China.Therefore,a better understanding of the impact of climate change on rapeseed production in the basin is of both scientific and practical importance to Chinese oil industry and food security.In this study,based on climate data from 5 General Circulation Models(GCMs) with 4 representative concentration pathways(RCPs) in 2011–2040(2020 s),2041–2070(2050 s) and 2071–2100(2080 s),we assessed the changes in rapeseed production potential between the baseline climatology of 1981–2010 and the future climatology of the 2020 s,2050 s,and 2080 s,respectively.The key modelling tool – the AEZ model – was updated and validated based on the observation records of 10 representative sites in the basin.Our simulations revealed that:(1) the uncertainty of the impact of climate change on rapeseed production increases with time;(2) in the middle of this century(2050 s),total rapeseed production would increase significantly;(3) the average production potential increase in the 2050 s for the upper,middle and lower reaches of the Yangtze River Basin is 0.939,1.639 and 0.339 million tons respectively;(4) areas showing most significant increases in production include southern Shaanxi,central and eastern Hubei,northern Hunan,central Anhui and eastern Jiangsu.  相似文献   

10.
正On November 17–18, the 2018 Academic Annual Meeting of China Society of Cryospheric Science was held successfully in Foshan City, Guangdong Province. In the context of global warming, the cryosphere is undergoing significant changes and has major impacts on global and regional ecosystems and socio-economic sustainability. In order to further promote the development process of China's cryosphere science, strengthen the exchanges between scientific research personnel in different sectors and fields, further condense the scientific research team of the cryosphere science, explore the new development directions of the cryosphere science, and  相似文献   

11.
Based on analysis of parameters of cores taken from Gaoyou Lake, including magnetic susceptibility, grain-size characteristics and sedimentary rate, environmental changes during the modern period were examined with the assistance of historical records and Gaoyou Lake water level materials. It is concluded that during the modern period a higher value of magnetic susceptibility and a lower sediment grain size coincided with a wet climate, while a lower value of magnetic susceptibility and a higher grain size were related with a dry climate. The results indicate that the climate in the 123 years period from 1880 to 2003AD can be divided into four stages: two low water level stages (1880–1915AD, 1948–1981AD) and two high water level stages (1915–1948AD, 1981–2003AD). It appears that the regional cli-mate generally underwent a dry–wet–dry–wet pattern in 30-year cycles. At present, it is at the end of a wet period, so the regional climate is expected to become dry in the near future. This conclusion corresponds with the climate records in the historical literature of the Gaoyou area, and it also matches with the climatic changes in North Jiangsu area.  相似文献   

12.
Based on analysis of parameters of cores taken from Gaoyou Lake, including magnetic susceptibility, grain-size characteristics and sedimentary rate, environmental changes during the modern period were examined with the assistance of historical records and Gaoyou Lake water level materials. It is concluded that during the modern period a higher value of magnetic susceptibility and a lower sediment grain size coincided with a wet climate, while a lower value of magnetic susceptibility and a higher grain size were related with a dry climate. The results indicate that the climate in the 123 years period from 1880 to 2003AD can be divided into four stages: two low water level stages (1880-1915AD, 1948-1981AD) and two high water level stages (1915-1948AD, 1981-2003AD). It appears that the regional climate generally underwent a dry-wet-dry-wet pattern in 30-year cycles. At present, it is at the end of a wet period, so the regional climate is expected to become dry in the near future. This conclusion corresponds with the climate records in the historical literature of the Gaoyou area, and it also matches with the climatic changes in North Jiangsu area.  相似文献   

13.
通过对腾格里沙漠东南部昂格尔图湖岩芯AGE15A的粒度、碳酸盐的百分含量和主要化学元素等多项沉积学气候代用指标及精确定年的综合分析,重建了该区域988 AD以来的古气候变化序列。结果表明:988 AD以来的研究区的气候环境的演化过程与我国西北西风区古气候变化基本一致,呈现"冷湿-暖干"交替变化的特征,但在时间上存在一定的延迟。具体表现为:988~1383 AD,昂格尔图湖由洼地发育成小型湖泊,化学风化作用弱,湖区气候环境整体偏冷湿,期间出现几次暖波动;1383~1560 AD,研究区处在中世纪暖期,为温暖、干旱的气候特征,此时湖泊扩张,湖中水生植物生长茂盛,呼吸作用增强,造成大量的碳酸盐沉淀,最高值达到8.16%;1560~1700 AD,致使气候在昂格尔图湖形成之后出现最寒冷的时期,降水增加,气候湿冷,此时段与小冰期最盛期相对应;1700 AD之后,温度开始上升,气候回暖,在1900 AD左右达到最甚,此时沉积物中碳酸盐的百分含量也达到最大值,为10.15%,此期间湖泊继续扩张,出现几次气候冷波动。基于我国古代文献重建的历史时期气候变化基本不包括沙漠地区,所以本文利用湖相沉积记录来反演腾格里沙漠昂格尔图湖历史时期的气候环境演变,对中国沙漠研究有着重要参考价值,同时也为中国西北历史时期的气候重建提供科学依据。  相似文献   

14.
对滇北拱王山狐狸房峰南侧老碳房村附近冰蚀湖相沉积剖面进行粒度、磁化率分析,结合^14C年代,建立了8.4ka至今的古气候环境变化序列。全新世早期以来经历5次较明显的气候波动:8.4—7.7ka,磁化率(xlf)变化在1.62-3.88μm^3kg^-1,粒度平均值为5.46φ,气候凉湿;7.7~6.5ka,粒度均值为5.83φ,磁化率降低,变化在1.44-2.28μm^3kg^-1。之间,气候冷湿;6.5-4.7ka,粒度均值为5.95φ,磁化率值变化在1.53—3.65μm^3kg^-1之间,气候冷干;4.7-2.1ka,粒度均值为5.91φ,磁化率增加,变化在2.0—5.2μm^3kg^-1。之间,气候凉湿;2.1ka以来,粒径平均值为5.63φ,磁化率值显著增加,介于3.44-6.33μm^3kg^-1。之间,平均值为4.80μm^3kg^-1,气候以暖湿为主。  相似文献   

15.
通过黄土高原西部平凉剖面的植硅体分析,对黄土高原西部全新世中晚期气候进行研究,将研究时期的气候分为5个阶段:8.43~7.78KaB.P.,气候凉湿;7.78~7.17KaB.P.,气候暖湿;7.17~6.27KaB.P.,气候总体仍为暖湿,但较上带有变冷趋势;6.27~5.55KaB.P.,气候特征为凉湿;5.55~0KaB.P.,气候特征仍为凉湿,但具有偏凉干趋势。明显的气候波动与全新世中晚期全球变化可以对比,与相邻区域的孢粉、粒度、磁化率等研究工作结果较为一致。  相似文献   

16.
山东沂沭河流域2000BC前后古文化兴衰的环境考古   总被引:6,自引:0,他引:6  
高华中  朱诚  曹光杰 《地理学报》2006,61(3):255-261
龙山文化早、中期 (2600BC~2300BC),沂沭河流域气候暖湿,以水稻种植为主的农业十分发达,社会全面繁荣,聚落遗址的数量得到了极大的扩展。2260BC前后开始的降温,对龙山文化中、晚期 (2300BC~2000BC) 的面貌造成了显著影响。气温下降,使得水稻产量大幅度下降甚至绝产,加剧了人口与资源之间的矛盾,随之而来的便是人口的大量减少和文化面貌的改变。2000BC前后龙山文化被较为落后古朴的岳石文化所取代。  相似文献   

17.
中国西北干旱区小冰期的湿度变化特征   总被引:3,自引:0,他引:3  
选取中国西北干旱区11 条具有明确古湿度指示意义的气候记录, 结合冰芯、地层沉积、 湖泊沉积、树木年轮、河流阶地等各种研究资料和历史记载, 研究中国西北干旱区小冰期的湿 度变化。结果表明研究区小冰期(1400-1920 AD) 从整体而言处于相对湿润的阶段: 区内高大 山系降水处于较高时段- -西昆仑山古里雅冰芯积累量增大, 天山山间湖泊水位回升, 祁连山 敦德冰芯孢粉总浓度增加; 而盆地内流系统水量也出现了相应的变化- -塔里木盆地克里雅 河和塔里木河流量增大, 准噶尔盆地艾比湖水位上升, 巴丹吉林沙漠地下水补给量上升, 居延 海入湖水量增大, 湖面扩展, 青海湖盆地降水增加, 有效湿度增大, 苏干湖水体盐度降低, 入湖 水量/ 蒸发量之比升高。同时, 较高分辨率的湿度资料显示, 研究区东-南边缘地带在小冰期 内部存在次一级的干湿波动, 两个湿度较高的时期出现在16 世纪和18 世纪, 分别与小冰期内 部的两个相对温暖时期有很好的对应。中国西北相对湿润的小冰期主要是西风带强度增加和 位置南移造成该区域降水增多和全球性普遍降温导致有效湿度增大两个因素共同作用的结果, 研究区边缘地带小冰期内部冷干暖湿的配置则主要体现了夏季风的影响。  相似文献   

18.
岱海湖泊沉积物频率磁化率对历史时期环境变化的反映*   总被引:52,自引:4,他引:48  
在探讨封闭湖泊沉积物频率磁化率的环境意义的基础上,根据岱海DH32孔湖泊沉积物磁化率的测量结果,结合粒度、孢粉、历史资料和硅藻分析结果,对岱海历史时期的环境变化进行了探讨。研究认为:历史时期内陆封闭湖泊沉积物频率磁化率高值段指示气候偏湿阶段;低值段指示气候干旱阶段;DH32孔湖泊沉积物频率磁化率反映的近300年来岱海气候变化可划分七个阶段,并与粒度、孢粉、硅藻和历史资料的分析结果基本一致。湖泊沉积物频率磁化率是恢复历史时期环境变化的重要环境指标之一。  相似文献   

19.
为分析荆南三口河系水位演变规律与江湖水量交换关系。依据1956—2017年荆南三口、湖南四水、洞庭湖城陵矶站以及长江干流枝城站月平均水位及流量和该流域8个雨量站的降水数据,运用Mann-Kendall趋势检验法、回归分析、流量年特征值等方法研究了三口水位的时序演变特征及其与流量、降水、江湖水量交换、人类活动的关系。结果表明:① 与阶段一(1956—1966年)相比,阶段二(1967—1980年)、三(1981—2002年)、四(2003—2017年)河系年平均水位、年最高水位分别下降0.74 m、0.37 m,年最低水位上升0.07 m;② 在涨(4—5月)、丰(6—9月)、退(10—11月)、枯(12月—次年3月)四个水文节点上,最低水位降幅最大(-0.98 m),平均水位次之(-0.78 m),最高水位最小(0.55 m),并将其降幅按水文节点排序依次为退水期(-0.95 m)>丰水期(-0.61 m)>涨水期(-0.21 m)>枯水期(0.15 m);③ 河系水位变化与其流量变化有着较好的一致性(二者的相关系数r =0.65),与降水量相关性较弱(r =-0.16),但2002—2017年相对干旱的气候加剧了河系水位的下降。从总体上看,长江枝城来水量减少和以水利工程为代表的人类活动方式是导致荆南三口河系特征水位下降的主要驱动因素。  相似文献   

20.
何则  何元庆  王世金  庞娟  辛惠娟  刘婧 《中国沙漠》2016,36(5):1278-1285
基于历史文献中的旱涝灾害记录,采用5级制划分的旱涝灾害等级,使用系统聚类法将中国西北地区19个站点划分为7个分区,利用湿润指数公式重建了西北地区7个分区1470-2008年的年分辨率干湿变化序列,比较分析了各分区干湿气候变化的阶段特征、周期性及跃变现象。结果表明:重建序列信度较高,可用作气候干湿变化研究。西北地区7个分区1470-2008年干湿变化存在着11 a、25~35 a和80~100 a的3类周期变化。其中,11 a和25~35 a的两个周期变化在整个分析时间段内表现得较为稳定;80~100 a的周期变化则表现的较不稳定。世纪尺度和气候代尺度的跃变信号各区皆有出现,位于研究区两边的陕西和玉树地区出现最少,宁夏和格尔木地区次之;位置居中的兰州、张掖、西宁等地区跃变信号出现最多,是气候干湿变化的敏感地带。检测出的干湿跃变信号主要集中在17世纪前后,近百年气候干湿变化则相对稳定。  相似文献   

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