By combining living trees and archaeological wood, the annual mean temperatures were reconstructed based on ring-width indices of the mid-eastern Tibetan Plateau for the past 2485 years. The climate variations reveale...By combining living trees and archaeological wood, the annual mean temperatures were reconstructed based on ring-width indices of the mid-eastern Tibetan Plateau for the past 2485 years. The climate variations revealed by the reconstruction indicate that there were four periods to have average tem- peratures similar to or even higher than that mean of 1970 to 2000 AD. A particularly notable rapid shift from cold to warm, we call it the "Eastern Jin Event", occurred from 348 AD to 413 AD. Calculation re- sults show that the temperature variations over the mid-eastern Tibetan Plateau are not only repre- sentative for large parts of north-central China, but also closely correspond to those of the entire Northern Hemisphere over long time scales. During the last 2485 years, the downfall of most major dynasties in China coincides with intervals of low temperature. Compared with the temperature records in other regions of China during the last 1000 years, this reconstruction from the Tibetan Plateau shows a significant warming trend after the 1950s.展开更多
The precipitation at 17 stations over the middle and lower reaches of the Yellow River is reconstructed during the period of 1736―1910, using the snow and rainfall records in the Qing Dynasty, together with the instr...The precipitation at 17 stations over the middle and lower reaches of the Yellow River is reconstructed during the period of 1736―1910, using the snow and rainfall records in the Qing Dynasty, together with the instrumental observation data of precipitation and farmland soil moisture content. The soil physics model related to rainfall infiltration and the surface water bal-ance equation are taken as main reconstruction methodology. The field infiltration experiment by artificial rainfall is conducted to check the reliability. And the precipitation series over the middle and lower reaches of the Yellow River and its 4 sub-regions are established, going back to 1736. Analysis of the time series indicates that the abrupt change of precipitation from high to low oc-curs around 1915 over the middle and lower reaches of the Yellow River. During the three peri-ods of 1791―1805, 1816―1830 and 1886―1895, the precipitation is markedly higher than the mean of the series. While both the periods of 1916―1945 and 1981―2000 are characterized by less precipitation. Three periodicities of 22―25a, 3.9a and 2.7a are shown in the precipitation fluctuation over the middle and lower reaches of the Yellow River. Moreover, the periodical signal of 22―25a becomes weaker and weaker since the abrupt change of 1915 and disappears in the late 1940s, and then the periodical signal of 35―40a appears instead.展开更多
Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GI...Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.展开更多
Based on the historical records of the annual increase in the workforce (men older than 16 years of age), the annual new taxed cropland in the Shengjing area (Northeast China), the extreme climate events in North Chin...Based on the historical records of the annual increase in the workforce (men older than 16 years of age), the annual new taxed cropland in the Shengjing area (Northeast China), the extreme climate events in North China, and related management policies in Northeast China during 1661―1680, a case study has been conducted to investigate the relationship between the extreme climate events in North China and the migration to Northeast China for cultivation. This study has found that the migration to Northeast China for cultivation from 1661 to 1680 was a response to the drought events that occurred in North China. The upsurge of migration, which occurred in 1665―1680, was a response to the drought period during 1664―1680 in North China while the fewer disasters period in Northeast China. There were three migratory peaks during the upsurge of migration, which corresponded to the three drought events. The peaks of migration, however, often lagged behind the drought events about 1―2 years. The encourag-ing-migration policy, which was adopted to encourage cultivation in Northeast China, did not produce much migration into the region in the early Qing Dynasty. It did, however, provide a policy background, which ensured more than 10000 migrants per year to Northeast China when North China suffered from drought/flood disasters. As a response to the highest peak of migration induced by the severe droughts in North China during 1664―1667, a prohibiting-migration policy restricted further migration to Northeast China was carried out in 1668. Although the prohibiting-migration policy could not entirely stop the migrants fleeing from famine in North China to Northeast China, the migrants and cultivation were significantly reduced under the policy. The frequent changes of the policy on the years when taxation started after the land was cultivated were also related to climate events. The extreme climate events in North China, migration to Northeast China for cultivation, and the related management poli-cies showed an impa展开更多
To understand historical human-induced land cover change and its climatic effects, it is necessary to create historical land use datasets with explicit spatial information. Using the taxes-cropland area and number of ...To understand historical human-induced land cover change and its climatic effects, it is necessary to create historical land use datasets with explicit spatial information. Using the taxes-cropland area and number of families compiled from historical documents, we estimated the real cropland area and populations within each Lu （a province-level political region in the Northern Song Dynasty） in the mid-Northern Song Dynasty （AD1004-1085）. The estimations were accomplished through analyzing the contemporary policies of tax, population and agricultural development. Then, we converted the political region-based cropland area to geographically explicit grid cell-based fractional cropland at the cell size of 60 km by 60 km. The conversion was based on calculating cultivation suitability of each grid cell using the topographic slope, altitude and population density as the independent variables. As a result, the total area of cropland within the Northern Song territory in the 1070s was estimated to be about 720 million mu （Chinese area unit, 1 mu = 666.7 m2）, of which 40.1% and 59.9% oc- curred in the north and south respectively. The population was estimated to be about 87.2 million, of which 38.7% and 61.3% were in the north and south respectively, and per capita cropland area was about 8.2 mu. The national mean reclamation ratio （i.e. ratio of cropland area to total land area; RRA hereafter for short） was bout 16.6%. The plain areas, such as the North China Plain, the middle and lower reaches of the Yangtze River, Guanzhong Plain, plains surrounding the Dongting Lake and Poyang Lake and Sichuan Basin, had a higher RRA, being mostly over 40%; while the hilly and mountainous areas, such as south of Nanling Mountains, the southwest regions （excluding the Chengdu Plain）, Loess Plateau and south- east coastal regions, had a lower RRA, being less than 20%. Moreover, RRA varied with topographic slope and altitude. In the areas of low altitude （~〈250 m）, middle altitude （250-100 m） and high altit展开更多
During the war between Liao Dynasty(907-1125)and Northern Song Dynasty(960-1127),there was a classic battle that happened in Yanmen Pass(located in today’s Dai County,Xinzhou,Shanxi Province,China).It was a well know...During the war between Liao Dynasty(907-1125)and Northern Song Dynasty(960-1127),there was a classic battle that happened in Yanmen Pass(located in today’s Dai County,Xinzhou,Shanxi Province,China).It was a well known battle of ancient China because a commander of the Song army named Yang Ye(?-986)was really famous in both classical Chinese fictions and Chinese war history.He is the early protagonist of a famous Chinese classic fiction named The Romance of the Yang family’s generals(written in the 16th century,Ming Dynasty of China).The story of his family also appears in other novels.Besides,in history,he was a general who was active in the early stages of the war between Liao Dynasty and Northern Song Dynasty.The battle of Yanmen Pass(980)was one of the most important battles of Yang’s military career.His combat style especially his cavalry tactic can be summarized through researching this battle.展开更多
All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Y...All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Yu the Great's flood control has a long history and is considered to be closely linked to the establishment of the Xia Dynasty. However, there is a lack of solid scientific evidence. Against this issue, some scholars have proposed that an earthquake around 1920 BCE in the Guanting Basin along the upper reaches of the Yellow River led to the creation of a lake by damming in the Jishi Gorge and that the outburst of water from that lake led to the massive flood in the Yellow River region. These studies provided new scientific evidence for the Chinese legend. In this paper, we date skeletal samples embedded in earthquake sand blasting from the Lajia site, analyze remains from natural disasters(such as earthquakes and floods) and also archaeological remains. In addition, we compared the skeletal samples dating with that of sediments from the dammed-up lake. Our results are inconsistent with those of previous scholars. The earthquake at the Lajia site occurred no earlier than 1800 BCE, and the dammed-up lake in Jishi Gorge had disappeared by 3600 BCE. Thus, the formation and outburst of the dammed lake, the sudden death of ancient humans at the Lajia site and the ancient earthquake were independent events occurring at different times. In addition, the massive flood in the upper reaches of the Yellow River did not actually happen. Thus, we argue against and invalidate the hypothesis that the massive flood was related to Yu the Great's flood control and the establishment of the Xia Dynasty.展开更多
Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland a...Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland areas for the years AD976, 997, 1066, and 1078 were estimated at the level of Lu（an administrative region of the Northern Song Dynasty）. The results indicated that（1） the cropland area of the whole study region for AD976, 997, 1066, and 1078 was about 468.27 million mu（a Chinese unit of area, with1 mu=666.7m2）, 495.53 million mu, 697.65 million mu, and 731.94 million mu, respectively. The fractional cropland area（FCA） increased from 10.7% to 16.8%, and the per capita cropland area decreased from 15.7 mu to 8.4 mu.（2） With regard to the cropland spatial pattern, the FCA of the southeast, north, and southwest regions of the Northern Song territory increased by 12.0%, 5.2%, and 1.2%, respectively. The FCA of some regions in the Yangtze River Plain increased to greater than 40%, and the FCA of the North China Plain increased to greater than 20%. However, the FCA of the southwest region（except for the Chengdu Plain） in the Northern Song territory was less than 6%.（3） There were 84.2% Lus whose absolute relative error was smaller than 20% in the mid Northern Song Dynasty. The validation results indicate that our models are reasonable and that the results of reconstruction are credible.展开更多
基金Supported by National Natural Science Foundation of China (Grant Nos. 40525004, 40599420, 40890051)National Basic Research Program of China (Grant Nos. 2007BAC30B00, 2004CB720200, 2006CB400503)the Swedish International Development Cooperation Agency (SIDA, Grant to Hans W. Linderholm)
文摘By combining living trees and archaeological wood, the annual mean temperatures were reconstructed based on ring-width indices of the mid-eastern Tibetan Plateau for the past 2485 years. The climate variations revealed by the reconstruction indicate that there were four periods to have average tem- peratures similar to or even higher than that mean of 1970 to 2000 AD. A particularly notable rapid shift from cold to warm, we call it the "Eastern Jin Event", occurred from 348 AD to 413 AD. Calculation re- sults show that the temperature variations over the mid-eastern Tibetan Plateau are not only repre- sentative for large parts of north-central China, but also closely correspond to those of the entire Northern Hemisphere over long time scales. During the last 2485 years, the downfall of most major dynasties in China coincides with intervals of low temperature. Compared with the temperature records in other regions of China during the last 1000 years, this reconstruction from the Tibetan Plateau shows a significant warming trend after the 1950s.
基金This study was supported by the Key Project from the National Natural Science Foundation of China(Grant No.40331013)the project from the Chinese Academy of Sciences(Grant No.KZCX3-SW-321).
文摘The precipitation at 17 stations over the middle and lower reaches of the Yellow River is reconstructed during the period of 1736―1910, using the snow and rainfall records in the Qing Dynasty, together with the instrumental observation data of precipitation and farmland soil moisture content. The soil physics model related to rainfall infiltration and the surface water bal-ance equation are taken as main reconstruction methodology. The field infiltration experiment by artificial rainfall is conducted to check the reliability. And the precipitation series over the middle and lower reaches of the Yellow River and its 4 sub-regions are established, going back to 1736. Analysis of the time series indicates that the abrupt change of precipitation from high to low oc-curs around 1915 over the middle and lower reaches of the Yellow River. During the three peri-ods of 1791―1805, 1816―1830 and 1886―1895, the precipitation is markedly higher than the mean of the series. While both the periods of 1916―1945 and 1981―2000 are characterized by less precipitation. Three periodicities of 22―25a, 3.9a and 2.7a are shown in the precipitation fluctuation over the middle and lower reaches of the Yellow River. Moreover, the periodical signal of 22―25a becomes weaker and weaker since the abrupt change of 1915 and disappears in the late 1940s, and then the periodical signal of 35―40a appears instead.
基金Major Program of Natural Science Research at University of Anhui Province, No.ZD200908 National Sci ence and Technology Support Program, No.2010BAK67B02+1 种基金 National Natural Science Foundation of China, No.41010104005 No.40971115This work is supported by the Tracing Origin Project of Chinese Civilization. We thank Dr. An Ran and Dr. Heim. Jordan in Purdue University, USA, for their kind help and valuable discussions.
文摘Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.
基金the National Natural Science Foundation of China (Grant No. 40271115)the Chinese Academy of Sciences (Grant No. KZCX3-sw-321)
文摘Based on the historical records of the annual increase in the workforce (men older than 16 years of age), the annual new taxed cropland in the Shengjing area (Northeast China), the extreme climate events in North China, and related management policies in Northeast China during 1661―1680, a case study has been conducted to investigate the relationship between the extreme climate events in North China and the migration to Northeast China for cultivation. This study has found that the migration to Northeast China for cultivation from 1661 to 1680 was a response to the drought events that occurred in North China. The upsurge of migration, which occurred in 1665―1680, was a response to the drought period during 1664―1680 in North China while the fewer disasters period in Northeast China. There were three migratory peaks during the upsurge of migration, which corresponded to the three drought events. The peaks of migration, however, often lagged behind the drought events about 1―2 years. The encourag-ing-migration policy, which was adopted to encourage cultivation in Northeast China, did not produce much migration into the region in the early Qing Dynasty. It did, however, provide a policy background, which ensured more than 10000 migrants per year to Northeast China when North China suffered from drought/flood disasters. As a response to the highest peak of migration induced by the severe droughts in North China during 1664―1667, a prohibiting-migration policy restricted further migration to Northeast China was carried out in 1668. Although the prohibiting-migration policy could not entirely stop the migrants fleeing from famine in North China to Northeast China, the migrants and cultivation were significantly reduced under the policy. The frequent changes of the policy on the years when taxation started after the land was cultivated were also related to climate events. The extreme climate events in North China, migration to Northeast China for cultivation, and the related management poli-cies showed an impa
基金China Global Change Research Program,No.2010CB950102No.2010CB950901National Natural Science Foundation of China,No.40971061
文摘To understand historical human-induced land cover change and its climatic effects, it is necessary to create historical land use datasets with explicit spatial information. Using the taxes-cropland area and number of families compiled from historical documents, we estimated the real cropland area and populations within each Lu （a province-level political region in the Northern Song Dynasty） in the mid-Northern Song Dynasty （AD1004-1085）. The estimations were accomplished through analyzing the contemporary policies of tax, population and agricultural development. Then, we converted the political region-based cropland area to geographically explicit grid cell-based fractional cropland at the cell size of 60 km by 60 km. The conversion was based on calculating cultivation suitability of each grid cell using the topographic slope, altitude and population density as the independent variables. As a result, the total area of cropland within the Northern Song territory in the 1070s was estimated to be about 720 million mu （Chinese area unit, 1 mu = 666.7 m2）, of which 40.1% and 59.9% oc- curred in the north and south respectively. The population was estimated to be about 87.2 million, of which 38.7% and 61.3% were in the north and south respectively, and per capita cropland area was about 8.2 mu. The national mean reclamation ratio （i.e. ratio of cropland area to total land area; RRA hereafter for short） was bout 16.6%. The plain areas, such as the North China Plain, the middle and lower reaches of the Yangtze River, Guanzhong Plain, plains surrounding the Dongting Lake and Poyang Lake and Sichuan Basin, had a higher RRA, being mostly over 40%; while the hilly and mountainous areas, such as south of Nanling Mountains, the southwest regions （excluding the Chengdu Plain）, Loess Plateau and south- east coastal regions, had a lower RRA, being less than 20%. Moreover, RRA varied with topographic slope and altitude. In the areas of low altitude （~〈250 m）, middle altitude （250-100 m） and high altit
文摘During the war between Liao Dynasty(907-1125)and Northern Song Dynasty(960-1127),there was a classic battle that happened in Yanmen Pass(located in today’s Dai County,Xinzhou,Shanxi Province,China).It was a well known battle of ancient China because a commander of the Song army named Yang Ye(?-986)was really famous in both classical Chinese fictions and Chinese war history.He is the early protagonist of a famous Chinese classic fiction named The Romance of the Yang family’s generals(written in the 16th century,Ming Dynasty of China).The story of his family also appears in other novels.Besides,in history,he was a general who was active in the early stages of the war between Liao Dynasty and Northern Song Dynasty.The battle of Yanmen Pass(980)was one of the most important battles of Yang’s military career.His combat style especially his cavalry tactic can be summarized through researching this battle.
基金supported by the National Natural Science Foundation of China(Grant Nos.41620104007,41671077 and41402240)
文摘All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Yu the Great's flood control has a long history and is considered to be closely linked to the establishment of the Xia Dynasty. However, there is a lack of solid scientific evidence. Against this issue, some scholars have proposed that an earthquake around 1920 BCE in the Guanting Basin along the upper reaches of the Yellow River led to the creation of a lake by damming in the Jishi Gorge and that the outburst of water from that lake led to the massive flood in the Yellow River region. These studies provided new scientific evidence for the Chinese legend. In this paper, we date skeletal samples embedded in earthquake sand blasting from the Lajia site, analyze remains from natural disasters(such as earthquakes and floods) and also archaeological remains. In addition, we compared the skeletal samples dating with that of sediments from the dammed-up lake. Our results are inconsistent with those of previous scholars. The earthquake at the Lajia site occurred no earlier than 1800 BCE, and the dammed-up lake in Jishi Gorge had disappeared by 3600 BCE. Thus, the formation and outburst of the dammed lake, the sudden death of ancient humans at the Lajia site and the ancient earthquake were independent events occurring at different times. In addition, the massive flood in the upper reaches of the Yellow River did not actually happen. Thus, we argue against and invalidate the hypothesis that the massive flood was related to Yu the Great's flood control and the establishment of the Xia Dynasty.
基金National Natural Science Foundation of China,No.41271227 The Special Program for Basic Work of the Ministry of Science and Technology,China,No.2014FY210900
文摘Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland areas for the years AD976, 997, 1066, and 1078 were estimated at the level of Lu（an administrative region of the Northern Song Dynasty）. The results indicated that（1） the cropland area of the whole study region for AD976, 997, 1066, and 1078 was about 468.27 million mu（a Chinese unit of area, with1 mu=666.7m2）, 495.53 million mu, 697.65 million mu, and 731.94 million mu, respectively. The fractional cropland area（FCA） increased from 10.7% to 16.8%, and the per capita cropland area decreased from 15.7 mu to 8.4 mu.（2） With regard to the cropland spatial pattern, the FCA of the southeast, north, and southwest regions of the Northern Song territory increased by 12.0%, 5.2%, and 1.2%, respectively. The FCA of some regions in the Yangtze River Plain increased to greater than 40%, and the FCA of the North China Plain increased to greater than 20%. However, the FCA of the southwest region（except for the Chengdu Plain） in the Northern Song territory was less than 6%.（3） There were 84.2% Lus whose absolute relative error was smaller than 20% in the mid Northern Song Dynasty. The validation results indicate that our models are reasonable and that the results of reconstruction are credible.
