Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandoned during the Northern and Southern Dynasties, 21.05% ...Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandoned during the Northern and Southern Dynasties, 21.05% during the end of the Tang Dynasty and the Five Dynasties, and 57.9% during the Ming and Qing dynasties. At the same time, main lakes were shrinking rapidly from the 5th Century to the 6th Century and the end of the Qing Dynasty. The climate in these periods was relatively arid and cold with frequent dusts. The phase of these changes indicated that there were three periods of desertification enlargement in the northern China. They were Northern and Southern Dynasties, the end of Tang Dynasty and Five Dynasties, the Ming and Qing dynasties. The macro-process of desertification in the study area was controlled mainly by the climatic changes. But from the facts that the population density in the middle of Qing Dynasty had exceeded the critical index of population pressure in arid area and the usage rate of water resources had exceeded 40% in Hexi Corridor, this paper also suggests that human activities have played an important role in desertification processes of the study area mainly during the recent 300 years.展开更多
Historical desertification of the Mu Us Sandy Land is linked to both environmental changes and anthropogenic activities. This paper reports on an analysis of grain size parameters as indicative of such changes in the ...Historical desertification of the Mu Us Sandy Land is linked to both environmental changes and anthropogenic activities. This paper reports on an analysis of grain size parameters as indicative of such changes in the southwestern area of the Mu Us Sandy Land. Combined with analysis of chronologies and historical records, our results indicate that Beidachi Lake and a nearby season- al river have retreated continuously in history and that sand dunes appeared at approximately the end of the Ming dynasty. This study sheds new light on the understanding of spatial-temporal changes of the interior Mu Us Sandy Land in history and has great significance in revealing environmental changes of the interior region of the Mu Us Sandy Land.展开更多
Songnen Sandy Land lies in the eastern fringe of huge sandy belt of middle latitude inEurasia Continent Here is also the eastern fringe of desertification-prone land in China. Its specialconditions such as biology and...Songnen Sandy Land lies in the eastern fringe of huge sandy belt of middle latitude inEurasia Continent Here is also the eastern fringe of desertification-prone land in China. Its specialconditions such as biology and climate, the history of evolution of sandy land and its location make itpossess features differing from other sandy lands in the country. This article systematitaly discussesthe regional featured such as the historical process, modern process, environmental factors ondesertification and the sandy land landscape and the degree of desertification, and raises some advicesfor rehabilitation and development in this area.展开更多
文摘Over the last 2000 years, approximately 38 ancient cities were abandoned through desertification in Hexi Corridor, Northwest China. Among them, 21.05% were abandoned during the Northern and Southern Dynasties, 21.05% during the end of the Tang Dynasty and the Five Dynasties, and 57.9% during the Ming and Qing dynasties. At the same time, main lakes were shrinking rapidly from the 5th Century to the 6th Century and the end of the Qing Dynasty. The climate in these periods was relatively arid and cold with frequent dusts. The phase of these changes indicated that there were three periods of desertification enlargement in the northern China. They were Northern and Southern Dynasties, the end of Tang Dynasty and Five Dynasties, the Ming and Qing dynasties. The macro-process of desertification in the study area was controlled mainly by the climatic changes. But from the facts that the population density in the middle of Qing Dynasty had exceeded the critical index of population pressure in arid area and the usage rate of water resources had exceeded 40% in Hexi Corridor, this paper also suggests that human activities have played an important role in desertification processes of the study area mainly during the recent 300 years.
基金supported by National Natural Science Foundation of China (41101187)the Specialized Research Fund for the Doctoral Program of Higher Education (20100211120006)+2 种基金the Ministry of Education, Humanities and Social Science Projects (10YJCZH053)the Fundamental Research Funds for the Central Universities (LZUJBKY-2012-136)the National Science Foundation for Post-Doctoral Scientists of China (2012M512051)
文摘Historical desertification of the Mu Us Sandy Land is linked to both environmental changes and anthropogenic activities. This paper reports on an analysis of grain size parameters as indicative of such changes in the southwestern area of the Mu Us Sandy Land. Combined with analysis of chronologies and historical records, our results indicate that Beidachi Lake and a nearby season- al river have retreated continuously in history and that sand dunes appeared at approximately the end of the Ming dynasty. This study sheds new light on the understanding of spatial-temporal changes of the interior Mu Us Sandy Land in history and has great significance in revealing environmental changes of the interior region of the Mu Us Sandy Land.
文摘Songnen Sandy Land lies in the eastern fringe of huge sandy belt of middle latitude inEurasia Continent Here is also the eastern fringe of desertification-prone land in China. Its specialconditions such as biology and climate, the history of evolution of sandy land and its location make itpossess features differing from other sandy lands in the country. This article systematitaly discussesthe regional featured such as the historical process, modern process, environmental factors ondesertification and the sandy land landscape and the degree of desertification, and raises some advicesfor rehabilitation and development in this area.
