Based on the runoff and meteorological data of Langan（兰干） Hydrological Station from 1957 to 2009 in Keriya（克里雅） River,the periodicities,abrupt changes,and trends of climate factors and runoff were investigate...Based on the runoff and meteorological data of Langan（兰干） Hydrological Station from 1957 to 2009 in Keriya（克里雅） River,the periodicities,abrupt changes,and trends of climate factors and runoff were investigated by wavelet analysis and nonparametric test;then,the future change of the annual runoff was predicted by a periodic trend superposition model.In succession,the influencing volumes of climate change on the annual runoff were separated from the observation values of the an-nual runoff in Keriya River.The results show that（1） temperature series increased significantly,while the annual runoff and precipitation of Keriya River increased insignificantly at the significant level of α=0.05;（2） the common periods of 9 and 15 years existed in the annual runoff evolution process,and the primary periods of temperature and precipitation were 9 and 22 years and 9 and 13 years,respec-tively;（3） the annual runoff did not vary simultaneously with the abrupt change of climate factors in the headstream;the abrupt points of annual runoff and temperature are at 1998 and 1980 year,and that of precipitation is not so significant;and（4） the annual runoff will experience a decrease trend in the future period;the total increasing volume owing to climate change is 23.154×108 m3 in the head-stream during the period of 1999-2009;however,the stream flow has been nearly utilized completely due to the human activities in the mainstream area of Keriya River.展开更多
黄土是地质时期沙尘天气形成的粉尘堆积物,其粒度特征记录了粉尘搬运过程中的古大气环流格局和古环境演化信息。本文对昆仑山北坡克里雅河支流的第5级阶地羊场黄土剖面进行了系统的粒度分析,结果表明,黄土粒度组成主要以粗粉砂和砂砾为...黄土是地质时期沙尘天气形成的粉尘堆积物,其粒度特征记录了粉尘搬运过程中的古大气环流格局和古环境演化信息。本文对昆仑山北坡克里雅河支流的第5级阶地羊场黄土剖面进行了系统的粒度分析,结果表明,黄土粒度组成主要以粗粉砂和砂砾为主,分选较好;羊场黄土为塔克拉玛干沙漠的近源风成堆积,粒度指标主要指示沙漠范围和源区气候干旱程度;粒度结果的详细分析及其与全球其他记录的对比表明,塔里木盆地南缘气候在8.5~3.6 ka B.P.较为湿润稳定,3.6 ka B.P.以来气候急剧变干并出现大幅度波动的千年尺度突变事件,与其他地区古气候记录有较好的一致性。塔里木盆地南缘8.5 ka B.P.以来的气候变化具有季风模式和千年尺度气候振荡的双重特点,可能同时受低纬度亚洲季风和北半球高纬度地区气候的影响;太阳辐射减弱引起的亚洲夏季风衰退可能导致了3.6 ka B.P.以来盆地的干旱化,同时,受太阳辐射驱动的北半球高纬度地区的气候变化,可能通过增加西风环流的强度及其波动幅度,进一步加剧了3.6 ka B.P.以来塔里木盆地南缘气候的干旱化和不稳定性。展开更多
生态基流承担着维持河道形态稳定,保障河道内生态环境基本健康的作用。确定河流生态基流量对保护流域生态环境,促进区域经济社会发展有着十分重要的意义。以干旱区克里雅河为研究对象,根据兰干水文站月径流资料,分别采用Texas法、不同...生态基流承担着维持河道形态稳定,保障河道内生态环境基本健康的作用。确定河流生态基流量对保护流域生态环境,促进区域经济社会发展有着十分重要的意义。以干旱区克里雅河为研究对象,根据兰干水文站月径流资料,分别采用Texas法、不同频率最枯月平均值法(Q_(P)法)、典型水文频率年法、Northern Great Plains Resource Program法(NGPRP法)、最枯月平均流量法、频率曲线法以及年内展布法等7种水文学方法分别计算克里雅河生态基流量。从生态基流的基本功能出发,从维持河道基本形态稳定、保障河道水生生物基本生存,反映径流年内丰枯变化特征等三方面划定标准,评估不同方法生态基流计算结果的达标情况,综合分析评价不同计算方法的适用性。同时结合克里雅河径流特征,对传统生态基流计算方法Texas法进行适当改进。改进后的Texas法计算所得克里雅河全年生态基流对应水量1.89亿m^(3),约占全年径流总量的24.83%,汛期生态基流对应水量1.02亿m^(3),约占同时段径流量的20.1%;非汛期生态基流对应水量0.87亿m^(3),约占同时段径流量的34.4%。研究认为,改进后的Texas法计算得出的生态基流在满足年内不同时段、不同标准水量需求的同时,能更合理的兼顾干旱区河流年内分配差异大的径流特征以及流域水资源总量稀缺的实际情况。在保障河流发挥其基本功能、维持河道形态稳定,避免生态环境遭受严重破坏的前提下,将尽可能多的水资源用于当地日益增长的人民生产生活用水,较好的权衡了该地区生态环境用水与生产生活用水之间的矛盾,具有一定的现实意义。展开更多
Over one hundred artifacts, including shards, chopped wood, bronze and iron ware debris as well as footprints, have been discovered during archaeological investigations at and around the central Taklamakan Desert Yuan...Over one hundred artifacts, including shards, chopped wood, bronze and iron ware debris as well as footprints, have been discovered during archaeological investigations at and around the central Taklamakan Desert Yuansha Site (38°52′N, 81°35′E). Dating (14C and OSL) and landform study show that the present-day dry Keriya River once sustained an oasis human settle- ment in 2.6 ka BP, historically falling into the Spring and Autumn Period (716-475 BCE) of Chinese history. The chronology and archaeological interpretations also show that some 400 years later, the local Keriya River channel had shifted 40 km southeast to sustain a Western Han (206 BCE-25 CE) Wumi settlement at the Karadun site. In the meantime, river-channel migration had allowed reoccupation of a site west of Yuansha City around 1.9 ka BP (abandoned again by 1.6 ka BP). The remains' chronology shows that this site was affiliated to Wumi culture and Eastern Han (24-220 CE) dynasty rule. Palaeoclimatic records indicate that the migrations of the river and oasis settlers between 2.7 and 1.6 ka BP were coeval with Central Asian climate changes. Yuansha City was built just after the end of 2.8 ka BP glacier advances in western China, suggesting that release of more water during the subsequent glacier recession may have facilitated oasis development such that Iron Age European peoples could settle in the Tarim Basin. As shown from analysis of archeological remains, not only at Yuansha but also in other ancient cities in the Tarim such as Loulan and Jingjue (Niya), conditions around 1.6 ka BP were dry enough to cause oasis decline. Thus, the results reported here enhance our knowledge about environmental changes and their effects on human activities and cultural evolution in western China and will stimulate further interdisciplinary studies of landscape and oasis history in the Tarim Basin.展开更多
基金supported by the National Basic Research Program of China (No. 2009CB421308)the Ministry of Water Resources Special Fund for Scientific Research on Public Causes (No. 201101049)
文摘Based on the runoff and meteorological data of Langan（兰干） Hydrological Station from 1957 to 2009 in Keriya（克里雅） River,the periodicities,abrupt changes,and trends of climate factors and runoff were investigated by wavelet analysis and nonparametric test;then,the future change of the annual runoff was predicted by a periodic trend superposition model.In succession,the influencing volumes of climate change on the annual runoff were separated from the observation values of the an-nual runoff in Keriya River.The results show that（1） temperature series increased significantly,while the annual runoff and precipitation of Keriya River increased insignificantly at the significant level of α=0.05;（2） the common periods of 9 and 15 years existed in the annual runoff evolution process,and the primary periods of temperature and precipitation were 9 and 22 years and 9 and 13 years,respec-tively;（3） the annual runoff did not vary simultaneously with the abrupt change of climate factors in the headstream;the abrupt points of annual runoff and temperature are at 1998 and 1980 year,and that of precipitation is not so significant;and（4） the annual runoff will experience a decrease trend in the future period;the total increasing volume owing to climate change is 23.154×108 m3 in the head-stream during the period of 1999-2009;however,the stream flow has been nearly utilized completely due to the human activities in the mainstream area of Keriya River.
文摘黄土是地质时期沙尘天气形成的粉尘堆积物,其粒度特征记录了粉尘搬运过程中的古大气环流格局和古环境演化信息。本文对昆仑山北坡克里雅河支流的第5级阶地羊场黄土剖面进行了系统的粒度分析,结果表明,黄土粒度组成主要以粗粉砂和砂砾为主,分选较好;羊场黄土为塔克拉玛干沙漠的近源风成堆积,粒度指标主要指示沙漠范围和源区气候干旱程度;粒度结果的详细分析及其与全球其他记录的对比表明,塔里木盆地南缘气候在8.5~3.6 ka B.P.较为湿润稳定,3.6 ka B.P.以来气候急剧变干并出现大幅度波动的千年尺度突变事件,与其他地区古气候记录有较好的一致性。塔里木盆地南缘8.5 ka B.P.以来的气候变化具有季风模式和千年尺度气候振荡的双重特点,可能同时受低纬度亚洲季风和北半球高纬度地区气候的影响;太阳辐射减弱引起的亚洲夏季风衰退可能导致了3.6 ka B.P.以来盆地的干旱化,同时,受太阳辐射驱动的北半球高纬度地区的气候变化,可能通过增加西风环流的强度及其波动幅度,进一步加剧了3.6 ka B.P.以来塔里木盆地南缘气候的干旱化和不稳定性。
文摘生态基流承担着维持河道形态稳定,保障河道内生态环境基本健康的作用。确定河流生态基流量对保护流域生态环境,促进区域经济社会发展有着十分重要的意义。以干旱区克里雅河为研究对象,根据兰干水文站月径流资料,分别采用Texas法、不同频率最枯月平均值法(Q_(P)法)、典型水文频率年法、Northern Great Plains Resource Program法(NGPRP法)、最枯月平均流量法、频率曲线法以及年内展布法等7种水文学方法分别计算克里雅河生态基流量。从生态基流的基本功能出发,从维持河道基本形态稳定、保障河道水生生物基本生存,反映径流年内丰枯变化特征等三方面划定标准,评估不同方法生态基流计算结果的达标情况,综合分析评价不同计算方法的适用性。同时结合克里雅河径流特征,对传统生态基流计算方法Texas法进行适当改进。改进后的Texas法计算所得克里雅河全年生态基流对应水量1.89亿m^(3),约占全年径流总量的24.83%,汛期生态基流对应水量1.02亿m^(3),约占同时段径流量的20.1%;非汛期生态基流对应水量0.87亿m^(3),约占同时段径流量的34.4%。研究认为,改进后的Texas法计算得出的生态基流在满足年内不同时段、不同标准水量需求的同时,能更合理的兼顾干旱区河流年内分配差异大的径流特征以及流域水资源总量稀缺的实际情况。在保障河流发挥其基本功能、维持河道形态稳定,避免生态环境遭受严重破坏的前提下,将尽可能多的水资源用于当地日益增长的人民生产生活用水,较好的权衡了该地区生态环境用水与生产生活用水之间的矛盾,具有一定的现实意义。
基金supported by the National Basic Research Program of China (Grant No. 2009CB421308)the National Natural Science Foundation of China (Grant Nos. 40701188 and 40971020)+2 种基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region (Grant No. 2010211A12)the Natural Science Foundation of Xinjiang University (Grant No. BS060112)the Project of Oasis Ecological Key Lab of Education Ministry Xinjiang University (Grant No. XJDX0206-2007-08)
文摘Over one hundred artifacts, including shards, chopped wood, bronze and iron ware debris as well as footprints, have been discovered during archaeological investigations at and around the central Taklamakan Desert Yuansha Site (38°52′N, 81°35′E). Dating (14C and OSL) and landform study show that the present-day dry Keriya River once sustained an oasis human settle- ment in 2.6 ka BP, historically falling into the Spring and Autumn Period (716-475 BCE) of Chinese history. The chronology and archaeological interpretations also show that some 400 years later, the local Keriya River channel had shifted 40 km southeast to sustain a Western Han (206 BCE-25 CE) Wumi settlement at the Karadun site. In the meantime, river-channel migration had allowed reoccupation of a site west of Yuansha City around 1.9 ka BP (abandoned again by 1.6 ka BP). The remains' chronology shows that this site was affiliated to Wumi culture and Eastern Han (24-220 CE) dynasty rule. Palaeoclimatic records indicate that the migrations of the river and oasis settlers between 2.7 and 1.6 ka BP were coeval with Central Asian climate changes. Yuansha City was built just after the end of 2.8 ka BP glacier advances in western China, suggesting that release of more water during the subsequent glacier recession may have facilitated oasis development such that Iron Age European peoples could settle in the Tarim Basin. As shown from analysis of archeological remains, not only at Yuansha but also in other ancient cities in the Tarim such as Loulan and Jingjue (Niya), conditions around 1.6 ka BP were dry enough to cause oasis decline. Thus, the results reported here enhance our knowledge about environmental changes and their effects on human activities and cultural evolution in western China and will stimulate further interdisciplinary studies of landscape and oasis history in the Tarim Basin.
