1971年以来珠穆朗玛峰地区气候变化

Global climate change has profound influence on natural ecosystem and socioeconomic system and is a focus which governments, scientific societies as well as common people of various countries have paid much attention to. Observations indicate that there i…     

近30年珠穆朗玛峰国家自然保护区冰川变化的遥感监测

利用1976、1988和2006年的3期陆地卫星遥感数据,采用面向对象的解译方法并结合专家知识分类规则自动提取珠穆朗玛峰国家自然保护区(以下简称珠峰保护区)3个时期的冰川信息,并利用遥感、地理信息系统和图谱的方法对冰川时空分布特征和变化及其原因与不确定性进行了分析。结果如下:(1)2006年珠峰保护区内冰川面积为2710.17±0.011km²,为研究区总面积的7.41%,主要分布在研究区南部海拔4700～6800m的高山区;(2)1976-2006年,珠峰保护区冰川持续退缩明显,总面积减少501.91±0.035km²,冰湖扩张迅速(净增加36.88±0.035km²);研究区南坡子流域冰川退缩率(16.79%)高于北坡子流域(14.40%);珠峰保护区冰川以退缩为主,退缩冰川主要分布于海拔4700～6400m,退缩区上限海拔为6600～6700m;(3)1976年以来,气温显著上升和降水减少是冰川退缩的关键因素。     

近50年黑河流域的冰川变化遥感分析(英文)

The Heihe River Basin is the second largest inland river basin in Northwest China and it is also a hotspot in arid hydrology, water resources and other aspects of researches in cold regions. In addition, the Heihe River Basin has complete landscape, moderate watershed size, and typical social ecological environmental problems. So far, there has been no detailed assessment of glaciers change information of the whole river basin. 1:50,000 topographic map data, Landsat TM/ETM+ remote sensing images and digital elevation model data were used in this research. Through integrated computer automatic interpretation and visual interpretation methods, the object-oriented image feature extraction method was applied to extract glacier outline information. Glaciers change data were derived from analysis, and the glacier variation and its response to climate change in the period 1956/1963–2007/ 2011 were also analyzed. The results show that:(1) In the period 1956/1963–2007/2011, the Heihe River Basin's glaciers had an evident retreat trend, the total area of glaciers decreased from 361.69 km2 to 231.17 km~2; shrinking at a rate of 36.08%, with average single glacier area decrease 0.14 km~2; the total number of the glaciers decreased from 967 to 800.(2) Glaciers in this basin are mainly distributed at elevations of 4300–4400 m, 4400–4500 m and 4500–4600 m; and there are significant regional differences in glaciers distribution and glaciers change.(3) Compared with other western mountain glaciers, glaciers retreat in the Heihe River Basin has a higher rate.(4) Analysis of the six meteorological stations' annual average temperature and precipitation data from 1960 to 2010 suggests that the mean annual temperature increased significantly and the annual precipitation also showed an increasing trend. It is concluded that glacier shrinkage is closely related with temperature rising, besides, glacier melting caused by rising temperatures greater than glacier mass supply by increased precipitation to some extent.     

珠穆朗玛峰地区近34年来气候变化

利用珠穆朗玛峰地区中国境内5个气象站1971~2004年月平均气温、月平均最高、最低气温、月降水资料,采用气候线性趋势分析、滑动平均、低通滤波、累积距平等方法对珠峰地区近34年气候变化的时空分布特征进行了分析。结果表明：(1) 1971~2004年珠峰地区气温呈现出明显的上升趋势,其中海拔最高的定日站增幅最高,且以冬半年非生长季气温增长更为显著;(2) 近34年珠峰地区的变暖要明显早于中国及全球,且升温幅度更大;(3) 珠峰南、北翼降水变化趋势明显不同,北翼4站降水以增加趋势为主,但是总体显著性水平不高,而珠峰南翼的聂拉木降水以减少趋势为主,从90年代初开始降水以较大幅度减少;(4) 与已有研究结果比较发现：珠峰高海拔地区是中国同期升温最显著的区域。设立在海拔5032 m珠峰大本营的世界上海拔最高的无人值守实时自动气象站将会在全球变化监测中发挥重要的作用。     

拉萨地区土地利用动态分析(英文)

Land use change is the result of the interplay between socioeconomic, institutional and environmental factors, and has important impacts on the functioning of socioeconomic and environmental systems with important tradeoffs for sustainability, food security, biodiversity and the vulnerability of people and ecosystems to global change impacts. Based on the results of the First Land Use Survey in Tibet Autonomous Region carried out in the late 1980s, land use map of Lhasa area in 1990 was compiled for the main agricultural area in Lhasa valley using aerial photos obtained in April, May and October 1991 and Landsat imagery in the late 1980s and 1991 as remotely sensed data sources. Using these remotely sensed data, the land use status of Lhasa area in 1991, 1992, 1993, 1995, 1999 and 2000 were mapped through updating annual changes of cultivated land, artificial forest, grass planting, grassland restoration, and residential area and so on. Land use map for Lhasa area in 2007 was made using ALOS AVNIR-2 composite images acquired on October 24 and December 26, 2007 through updating changes of main land use types. According to land use status of Lhasa area in 1990, 1995, 2000 and 2007, the spatial and temporal land use dynamics in Lhasa area from 1990 to 2007 are further analyzed using GIS spatial models in this paper.     

1990年以来中国小麦农业气象灾害时空变化特征(英文)

Agro-meteorological disasters(AMD) have become more frequent with climate warming. In this study, the temporal and spatial changes in the occurrence frequency of major meteorological disasters on wheat production were firstly explored by analyzing the observed records at national agro-meteorological stations(AMS) of China from 1991 to 2009. Furthermore, impact of climate change on AMD was discussed by comparing the warmer decade(2000–2009) with another decade(1991–2000). It was found that drought was the most frequent disaster during the last two decades, with a highest proportion of 79%. And the frequency of AMD increased significantly with climate change. Specifically, the main disasters occurred more frequently in the reproductive period than in the vegetative period. Besides, the spatial changes in the AMD frequency were characterized by region-specific. For example, the wheat cultivation areas located on the Loess Plateau and the middle-lower reaches of the Yellow River suffered mainly from drought. All these results were strongly linked to climate change in China. Therefore, sound adaptation options should be taken based on the latest changes of AMD under global warming to reduce agricultural damages.     

1971-2009 年珠穆朗玛峰地区尼泊尔境内气候变化

利用珠穆朗玛峰南坡尼泊尔境内(科西河流域) 的10 个气象站1971-2009 年月平均气温、月平均最高、最低气温和逐月降水资料, 采用线性趋势、Sen 斜率估计、Mann-Kendall 等方法分析区域气候变化状况及其时空特征, 并与珠穆朗玛峰北坡地区气候进行比较, 分析了珠穆朗玛峰地区气候变化的特征与趋势。结果表明:(1) 1971-2009 年间, 珠穆朗玛峰南坡年平均气温为20.0℃, 线性升温率为0.25℃/10a, 与北坡主要受年平均最低气温影响相反, 增幅主要受年平均最高气温升高的影响, 并且在1974 年及1992 年间出现两次显著增温, 增温特别明显的月份为2 月和9 月;(2) 该地区降水变化的局地性较强, 近40 年间年平均降水量为1729.01 mm, 年平均降水量以每年约4.27 mm的线性增幅有所增加, 但并不显著, 且降水月变化和季变化特征均不明显;(3) 由于珠穆朗玛峰南坡受到季风带来暖湿气流和喜马拉雅山阻挡的双重影响, 珠峰南坡的年平均降水量远高于北坡;(4) 珠穆朗玛峰南坡气温变暖的海拔依赖性并不明显, 且南坡地区的变暖趋势并没有北坡变暖趋势明显。     

三江源地区1961-2010年降水时空变化(英文)

Based on a monthly dataset of precipitation time series (1961-2010) from 12 meteorological stations across the Three-River Headwater Region (THRHR) of Qinghai Province, China, the spatio-temporal variation and abrupt change analysis of precipitation were examined by using moving average, linear regression, spline interpolation, the Mann-Kendall test and so on. Major conclusions were as follows. (1) The long-term annual and seasonal precipitation in the study area indicated an increasing trend with some oscillations during 1961-2010; however, the summer precipitation in the Lantsang (Lancang) River Headwater Region (LARHR), and the autumn precipitation in the Yangtze River Headwater Region (YERHR) of the THRHR decreased in the same period. (2) The amount of annual precipitation in the THRHR and its three sub-headwater regions was greater in the 1980s and 2000s. The springs were fairly wet after the 1970s, while the summers were relatively wet in the 1960s, 1980s and 2000s. In addition, the amount of precipitation in the autumn was greater in the 1970s and 1980s, but it was relatively less for the winter precipitation, except in the 1990s. (3) The normal values of spring, summer, winter and annual precipitation in the THRHR and its three sub-headwater regions all increased, but the normal value of summer precipitation in the LARHR had a negative trend and the normal value of winter precipitation declined in general. (4) The spring and winter precipitation increased in most of the THRHR. The summer, autumn and annual precipitation increased mainly in the marginal area of the west and north and decreased in the regions of Yushu, Zaduo, Jiuzhi and Banma. (5) The spring and winter precipitation in the THRHR and its three sub-headwater regions showed an abrupt change, except for the spring precipitation in the YARHR. The abrupt changes of spring precipitation were mainly in the late 1980s and early 1990s, while the abrupt changes of winter precipitation were primary in the mid-to late 1970s. This research would be helpful for further understanding the trends and periodicity of precipitation and for watershed-based water resource management in the THRHR.     

1959-2008年新疆阿尔泰山友谊峰地区冰川变化特征

 利用1959年地形图、2008年ASTER数字遥感影像及数字高程模型,在地理信息系统技术支持下分析了新疆阿尔泰山友谊峰地区冰川的变化特征。研究表明：1959-2008年该区冰川整体呈萎缩趋势,且变化幅度相对较大。相对于1959年,2008年冰川面积和数量分别变化-32.5%和-27.9%。其中,小于1 km2的冰川面积平均变化率为-66.7%,面积小于0.5 km2的冰川面积变化率大于-70%,面积大于1 km2以上的冰川面积变化率为-35.0%,1~5 km2的冰川面积变化率为-27.9%。冰川末端平均后退253 m,末端退缩比例为-18.3%,且南坡冰川末端变化率大于北坡。分析发现,研究区冰川面积亏损较大主要缘于该区小冰川分布数量较多（面积小于1 km2的冰川数量达75%),对气候变化的响应较为敏感。     

1976年以来香港入境旅游关系圈变化及指示性

入境旅游是衡量一个旅游目的地发展和国际化程度的重要标志。本文引入社会学人际关系理论与地理学距离衰减理论相结合,提出入境旅游关系圈（ITRC）的三层结构概念模型：周边圈、洲内圈和洲际圈。随后,以香港为案例提出了香港入境旅游关系圈（HKITRC）概念模型假设与实际HKITRC变化的指示性假设。在1976-2013年香港各入境客源地的旅游统计数据的基础上,利用空间分层与时间分段的方法对40年来实际HKITRC的变化及指示性进行了深入的实证分析。研究结果验证了假设,总结得出了40年来实际HKITRC三层结构和其内部各地区的变化规律,也证明了实际HKITRC变化对签证政策、人口规模、政治归属、文化传统和经济兴衰这5种因素的指示性。研究对学界及业界认识旅游目的地入境旅游关系圈的变化规律及其指示作用有一定启发和现实意义。     

1972～2013年东天山博格达峰地区冰川变化遥感监测

利用1972年MSS,1990、1999年TM和2013年ETM+遥感影像资料作为数据源,通过目视解译结合GIS技术,提取博格达峰地区4期冰川边界,同时对研究区周边气温降水进行趋势分析和周期分析,研究其与冰川的响应关系。结果表明:1 1972~2013年冰川面积退缩了23.79%(占1972年),退缩速率为0.58%/a。1972~1990年冰川退缩较慢,为0.38%/a,近20 a来冰川退缩加剧,达到0.74%/a;2冰川规模越小,退缩越快;3东南坡退缩最快,东坡次之,北坡最慢;4冰川退缩比率随坡度的变化呈正态分布;5研究区处于气温偏高期,降水偏少期,气候变暖是冰川退缩的主要原因;6对比发现该地区与天山其他区域冰川退缩速率相吻合。     

1980～2007年喜马拉雅东段洛扎地区冰川变化遥感监测

利用1980年地形图和多年遥感资料,采用目视解译方法手工提取了喜马拉雅东段洛扎地区4个时期的冰川信息,对冰川时空分布特征和变化与不确定性进行了分析,并结合近28年(1980～2007年)的气温、降水量资料对研究区的冰川变化原因进行了研究.结果表明:(1)1980～2007年,洛扎地区冰川面积从491.64 km<'2>...     

珠穆朗玛峰高海拔地区冰雪中的微量元素

珠穆朗玛峰(以下称“珠峰”)高海拔地区冰雪中微量元素的研究是1966—1968年珠峰地区表生地球化学和化学地理研究工作的继续。本文旨在通过对地表高海拔地区降水和冰雪覆盖中微量元素的地球化学研究,来阐明远离工业污染地区大气降水中微量元素的含量和分布特征。通过与南北极冰原地区的冰雪和大气气溶胶化学成分的对比分析,来探讨珠峰高海拔地区的大气质量,并追溯这些微量元素的来源。     

珠穆朗玛峰高海拔地区冰雪中的微量元素

珠穆朗玛峰(以下称“珠峰”)高海拔地区冰雪中微量元素的研究是1966—1968年珠峰地区表生地球化学和化学地理研究工作的继续。本文旨在通过对地表高海拔地区降水和冰雪覆盖中微量元素的地球化学研究,来阐明远离工业污染地区大气降水中微量元素的含量和分布特征。通过与南北极冰原地区的冰雪和大气气溶胶化学成分的对比分析,来探讨珠峰高海拔地区的大气质量,并追溯这些微量元素的来源。     

西辽河流域全新世以来的农业垦殖活动(英文)

The agricultural reclamations in the Xiliao River Valley since the Holocene have led to a huge landscape change from grassland to farmland. In this paper we reconsider the man-land relationship in the Xiliao River Valley by analyzing three major agricultural reclamations in prehistory, the Liao-Jin Dynasty and the period since the Qing Dynasty. We argue that when the demographic pressure appears in this area, especially during the last reclamation, the intraregional migration (second migration) is the major response to relieve such pressure, which also distinguishes two different settlement locations: "the initial area" and "the secondary area". Due to the environmental differences between these two areas, the cultivation on the latter one has caused more serious disturbance to the local environment. Thus the secondary area has become the key region which needs environmental management seri-ously.     

13kaBP以来黄土高原西部的植被与环境演化(英文)

Pollen records from the Chinese Loess Plateau revealed a detailed history of vegetation variation and associated climate changes during the last 13.0 ka BP.Before 12.1 ka BP,steppe or desert-steppe vegetation dominated landscape then was replaced by a coniferous forest under a generally wet climate(12.1-11.0 ka BP).The vegetation was deteriorated into steppe landscape and further into a desert-steppe landscape between 11.0 and 9.8 ka BP.After a brief episode of a cool and wet climate(9.8-9.6 ka BP),a relati...     

1975-2016年天山中段阿克苏河流域冰川变化分析（英文）

In this study, we analyzed glacier changes in the Aksu River Basin during the period 1975–2016, based on Landsat MSS/TM/ETM+/OLI imagery analysis and the Chinese Glacier Inventory(CGI). The results showed that the total number, area, and volume of the studied glaciers in the Aksu River Basin decreased by 202(7.65%), 965.7 km~2(25.88%), and 74.85–78.52 km~3(23.72%–24.3%), respectively. The rate of glacier retreat in the basin was slower in the north, northwest and west, but reached the highest in the east(measuring 0.86% yr~(-1)). Furthermore, there were significant regional differences in the distribution and change of glaciers, the Kumalak River Basin had the largest glacier number and area, about 63.15% and 76.47% of the studied basin, and the rate of glacier retreat in the Kumalak River Basin was 0.65% yr~(-1), it was higher than the Toxkan River Basin which reached 0.57% yr~(-1). We found the shrinkage rate of glacier for different periods in the past 41 years, during 1975–1990 the glaciers showed the greatest retreat, while the rate of glacier area retreat slowed down significantly from 1990 to 2000. In recent 16 years since 2000, the rate of glacier retreat in the Toxkan River Basin was higher compared with 1990–2000. The RGI50~(-1)3.04920 glacier of Kumalak River Basin had been in a state of retreat since 1990. Over the past 41 years, the temperature and precipitation in the Aksu River Basin increased obviously, and the warming temperatures were clearly the main reason for glacier retreat in the region, while the increased precipitation in the mountain area may have a direct relation with the retreating rate of glaciers.     

30年来呼伦贝尔地区草地植被对气候变化的响应(英文)

Global warming has led to significant vegetation changes especially in the past 20 years. Hulun Buir Grassland in Inner Mongolia, one of the world’s three prairies, is undergoing a process of prominent warming and drying. It is essential to investigate the effects of climatic change (temperature and precipitation) on vegetation dynamics for a better understanding of climatic change. NDVI (Normalized Difference Vegetation Index), reflecting characteristics of plant growth, vegetation coverage and biomass, is...     

1961-2010年三江源地区气温变化与突变分析(英文)

In this study, a monthly dataset of temperature time series (1961-2010) from 12 meteorological stations across the Three-River Headwater Region of Qinghai Province (THRHR) was used to analyze the climate change. The temperature variation and abrupt change analysis were examined by using moving average, linear regression, Spline interpo-lation, Mann-Kendall test and so on. Some important conclusions were obtained from this research, which mainly contained four aspects as follows. (1) There were several cold and warm fluctuations for the annual and seasonal average temperature in the THRHR and its three sub-headwater regions, but the temperature in these regions all had an obviously rising trend at the statistical significance level, especially after 2001. The spring, summer, autumn and annual average temperature increased evidently after the 1990s, and the winter average temperature exhibited an obvious upward trend after entering the 21st century. Except the standard value of spring temperature, the annual and seasonal temperature standard value in the THRHR and its three sub-headwater regions increased gradually, and the upward trend for the standard value of winter average temperature indicated significantly. (2) The tendency rate of annual average temperature in the THRHR was 0.36℃10a?1, while the tendency rates in the Yellow River Headwater Region (YERHR), Lancangjiang River Headwater Region (LARHR) and Yangtze River Headwater Region (YARHR) were 0.37℃10a?1, 0.37℃10a?1 and 0.34℃10a?1 respectively. The temperature increased significantly in the south of Yushu County and the north of Nangqian County. The rising trends of temperature in winter and autumn were higher than the upward trends in spring and summer. (3) The abrupt changes of annual, summer, autumn and winter average temperature were found in the THRHR, LARHR and YARHR, and were detected for the summer and autumn average temperature in the YERHR. The abrupt changes of annual and summer average temperatures were mainly in the late 1990s, while the abrupt changes of autumn and winter average temperatures ap-peared primarily in the early 1990s and the early 21st century respectively. (4) With the global warming, the diversities of altitude and underlying surface in different parts of the Tibetan Plateau were possibly the main reasons for the high increasing rate of temperature in the THRHR.     

1961–2011年中国南方地区极端降水事件变化(英文)

Based on the daily precipitation from a 0.5°×0.5° gridded dataset and meteorological stations during 1961–2011 released by National Meteorological Information Center, the reliability of this gridded precipitation dataset in South China was evaluated. Five precipitation indices recommended by the World Meteorological Organization(WMO) were selected to investigate the changes in precipitation extremes of South China. The results indicated that the bias between gridded data interpolated to given stations and the corresponding observed data is limited, and the proportion of the number of stations with bias between –10% and 0 is 50.64%. The correlation coefficients between gridded data and observed data are generally above 0.80 in most parts. The average of precipitation indices shows a significant spatial difference with drier northwest section and wetter southeast section. The trend magnitudes of the maximum 5-day precipitation(RX5day), very wet day precipitation(R95), very heavy precipitation days(R20mm) and simple daily intensity index(SDII) are 0.17 mm·a–1, 1.14 mm·a–1, 0.02 d·a–1 and 0.01 mm·d–1·a–1, respectively, while consecutive wet days(CWD) decrease by –0.05 d·a–1 during 1961–2011. There is spatial disparity in trend magnitudes of precipitation indices, and approximate 60.85%, 75.32% and 75.74% of the grid boxes show increasing trends for RX5 day, SDII and R95, respectively. There are high correlations between precipitation indices and total precipitation, which is statistically significant at the 0.01 level.