Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 ...Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 for Bao′an station, from 1955 to 2009 for Baoqing station, from 1956 to 2009 for Caizuizi station and from 1978 to 2009 for Hongqiling station. The influences of climate change and human activities on runoff change were investigated, and the causes of hydrological regime change were revealed. The seasonal runoff distribution of the Naoli River was extremely uneven, and the annual change was great. Overall, the annual runoff showed a significant decreasing trend. The annual runoff of Bao′an, Baoqing, and Caizuizi stations in 2009 decreased by 64.1%, 76.3%, and 84.3%, respectively, compared with their beginning data recorded. The wet and dry years of the Naoli River have changed in the study period. The frequency of wet year occurrence decreased and lasted longer, whereas that of dry year occurrence increased. The frequency of dry year occurrence increased from 25.0%-27.8% to 83.9%-87.5%. The years before the 1970s were mostly wet, whereas those after the 1970s were mostly dry. Precipitation reduction and land use changes contributed to the decrease in annual runoff. Rising temperature and water project construction have also contributed important effects on the runoff change of the Naoli River.展开更多
Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th cent...Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th century, the climate of the North China Plain experienced a shift from a relatively warm stage in the 18th century to a colder stage in the 19th century, which was characterised by a much colder climate and more frequent and severe floods and droughts. Historical information about refu- gees, social disorder, grain transportation, and disaster relief on the North China Plain in 1780-1819 is collected from the Ver- itable Records of the Qing Dynasty (a collection of official records). The mechanism of climate change affecting the food se- curity of the society, as indicated by the development of a refugee problem around the turn of the 19th century, is analyzed by examining the social vulnerability. There are four basic findings: (1) In the 40 years from 1780-1819, the society on the North China Plain was unstable and characterised by a significant deterioration of the refugee situation. The number of refugees in- creased markedly, and their behaviour became increasingly violent. In the 1780s, most of the disaster victims chose to stay at their residences waiting for relief. From 1790 to 1800, hundreds of thousands of refugees migrated to northeast China. In the 1810s, the frequency of farmer rebellions increased sharply. (2) The increase in instability corresponded to the climatic cooling over the same time period. The increased instability was a result of the negative impacts of climate change accumulating and transmitting to the social level. (3) For food security, a precondition for the negative impacts of climate change on human soci- ety was the vulnerability of the regional socioeconomic system, which had a high sensitivity and low capacity to respond. This vulnerability could be described by the following three observations: O The regional balance of supply and demand for food was in a critical state, which led to a high sensitivity and dramatic reduction in yield that was caused by climate change; (~ the capacity for disaster relief efforts by the government was too low to meet the needs of crisis management; (~ the capacity for refugees' resettlement in eastern Inner Mongolia and northeast China, which both border the North China Plain, was se- verely restricted by climatic conditions or the quarantine policy. (4) It is estimated that climate change caused the social vul- nerability to reach a critical level approximately 20 years earlier on the North China Plain.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 40830535, 41001110, 41101092, 41171092)National Basic Research Program of China (No. 2010CB951304)the CAS/SAFEA (Chinese Academy of Sciences/State Administration of Foreign Experts Affairs) International Partnership Program for Creative Research Teams, Eleventh Five-Year' Key Technological Projects of Heilongjiang Province Farm Bureau (No. HNK10A-10-01, HNK10A-10-03)
文摘Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 for Bao′an station, from 1955 to 2009 for Baoqing station, from 1956 to 2009 for Caizuizi station and from 1978 to 2009 for Hongqiling station. The influences of climate change and human activities on runoff change were investigated, and the causes of hydrological regime change were revealed. The seasonal runoff distribution of the Naoli River was extremely uneven, and the annual change was great. Overall, the annual runoff showed a significant decreasing trend. The annual runoff of Bao′an, Baoqing, and Caizuizi stations in 2009 decreased by 64.1%, 76.3%, and 84.3%, respectively, compared with their beginning data recorded. The wet and dry years of the Naoli River have changed in the study period. The frequency of wet year occurrence decreased and lasted longer, whereas that of dry year occurrence increased. The frequency of dry year occurrence increased from 25.0%-27.8% to 83.9%-87.5%. The years before the 1970s were mostly wet, whereas those after the 1970s were mostly dry. Precipitation reduction and land use changes contributed to the decrease in annual runoff. Rising temperature and water project construction have also contributed important effects on the runoff change of the Naoli River.
基金supported by National Basic Researh Program of China(Grant No. 2010CB950103)National Natural Science Foundation of China (Grant No. 41071127)
文摘Historical case studies of climate change impacts and the resulting social responses can provide analogies for better under- standing the impacts of current and future climate changes. Around the turn of the 19th century, the climate of the North China Plain experienced a shift from a relatively warm stage in the 18th century to a colder stage in the 19th century, which was characterised by a much colder climate and more frequent and severe floods and droughts. Historical information about refu- gees, social disorder, grain transportation, and disaster relief on the North China Plain in 1780-1819 is collected from the Ver- itable Records of the Qing Dynasty (a collection of official records). The mechanism of climate change affecting the food se- curity of the society, as indicated by the development of a refugee problem around the turn of the 19th century, is analyzed by examining the social vulnerability. There are four basic findings: (1) In the 40 years from 1780-1819, the society on the North China Plain was unstable and characterised by a significant deterioration of the refugee situation. The number of refugees in- creased markedly, and their behaviour became increasingly violent. In the 1780s, most of the disaster victims chose to stay at their residences waiting for relief. From 1790 to 1800, hundreds of thousands of refugees migrated to northeast China. In the 1810s, the frequency of farmer rebellions increased sharply. (2) The increase in instability corresponded to the climatic cooling over the same time period. The increased instability was a result of the negative impacts of climate change accumulating and transmitting to the social level. (3) For food security, a precondition for the negative impacts of climate change on human soci- ety was the vulnerability of the regional socioeconomic system, which had a high sensitivity and low capacity to respond. This vulnerability could be described by the following three observations: O The regional balance of supply and demand for food was in a critical state, which led to a high sensitivity and dramatic reduction in yield that was caused by climate change; (~ the capacity for disaster relief efforts by the government was too low to meet the needs of crisis management; (~ the capacity for refugees' resettlement in eastern Inner Mongolia and northeast China, which both border the North China Plain, was se- verely restricted by climatic conditions or the quarantine policy. (4) It is estimated that climate change caused the social vul- nerability to reach a critical level approximately 20 years earlier on the North China Plain.