Supported by MSS images in the mid and late 1970s,TM images in the early 1990s and TM/ETM images in 2004,grassland degradation in the＂Three-River Headwaters＂region （TRH region）was interpreted through analysis on R...Supported by MSS images in the mid and late 1970s,TM images in the early 1990s and TM/ETM images in 2004,grassland degradation in the＂Three-River Headwaters＂region （TRH region）was interpreted through analysis on RS images in two time series,then the spatial and temporal characteristics of grassland degradation in the TRH region were analyzed since the 1970s.The results showed that grassland degradation in the TRH region was a continuous change process which had large affected area and long time scale,and rapidly strengthen phenomenon did not exist in the 1990s as a whole.Grassland degradation pattern in the TRH region took shape initially in the mid and late 1970s.Since the 1970s,this degradation process has taken place continuously,obviously characterizing different rules in different regions.In humid and semi-humid meadow region,grassland firstly fragmentized, then vegetation coverage decreased continuously,and finally＂black-soil-patch＂degraded grassland was formed.But in semi-arid and arid steppe region,the vegetation coverage decreased continuously,and finally desertification was formed.Because grassland degradation had obviously regional differences in the TRH region,it could be regionalized into 7 zones, and each zone had different characteristics in type,grade,scale and time process of grassland degradation.展开更多
Largely due to population ageing,the cancer burden from older people has been rising,which imposed considerable pressure on current Chinese healthcare system.We provide comprehensive information about cancer burden of...Largely due to population ageing,the cancer burden from older people has been rising,which imposed considerable pressure on current Chinese healthcare system.We provide comprehensive information about cancer burden of Chinese older people based on the most recent data from National Central Cancer Registry of China.The logarithmic linear regression was used to project the current cancer burden in 2022,and Joinpoint regression was used for temporal trend analysis from 2000 to 2017.We also estimated cancer statistics of older people in the US,Japan and the Republic of Korea for comparisons.It is estimated that 2.79 million cases and 1.94 million deaths occur for Chinese older people,representing 55.8%and 68.2%of cases and deaths in all population in 2022.The overall cancer incidence rate gradually increased among older women,while the mortality rates declined for both sexes.Notably,approximately 10.0%of all cases and 17.7%of all deaths are from people aged over 80 years,and cancer incidence and mortality in this age group showed upward trends for women.Lung cancer and digestive cancers are the leading cancer types for Chinese older people.Compared with other countries,China has lower incidence rates but higher mortality rates for older people.The rapidly growing burden of prostate cancer,breast cancer,colorectal cancer,and declines in esophageal cancer,stomach cancer,and liver cancer among older people indicate the cancer pattern in China is being in a transition stage to that in developed countries.Our findings imply that it should be the national health priority to meet the growing demands for cancer diagnosis,treatment and care services from the older people as the rapid population ageing in next few decades.展开更多
Daily maximum/minimum temperatures and relative humidity records from 510 stations in China for the period 1960–2008 were used to investigate geographical patterns and temporal variations of heatwave （HW） events. D...Daily maximum/minimum temperatures and relative humidity records from 510 stations in China for the period 1960–2008 were used to investigate geographical patterns and temporal variations of heatwave （HW） events. Dry and wet HW events were compared by different definitions. Regionally, both dry and wet HW events are commonly located in southeastern China in the monsoon area, with neither type occurring in the northeast part of Northeast China and Southwest China, while the north-northwest region of the country experiences dry HW events and a few wet HW events. In the southeast of the country, site dry HW events occurred from April to September and mostly in June, while site wet HW events occurred from April to October and mostly in September. In total, 163 regional wet HW events were identified. The ten longest regional wet HW events lasted for more than 20 days, while the mean duration for 163 events was about 11 days. For the top ten events, six occurred after the 1990s, compared with four before this time. Global surface warming was clear since 1979, but the frequency and severity of regional wet HW events were relatively low in the 1980s, increasing remarkably since the 1990s. Possible reasons for this might be the strong interdecadal and interannual variations in regional atmospheric circulations, as well as water transport related directly to temperature contrasts in different regions, rather than global-mean temperature changes.展开更多
As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China＇s economy. However, little research has grasped the essence o...As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China＇s economy. However, little research has grasped the essence of the economic development stage and the spatio-temporal evolution process at the prefecture level; this may lead to biased policies and their ineffective implementations. Based on Chenery＇s economic development theory, this paper identifies China＇s economic development stages at both national and prefectural levels. Both the Global Moran I index and the Getis-Ord Gi＊ index are employed to investigate the spatio-temporal evolution of China＇s economic development from 1990 to 2010. Major conclusions can be drawn as follows. （1） China＇s economic development is generally in the state of agglomeration. It entered the Primary Production Stage in 1990, and the Middle Industrialized Stage in 2010, with a ＇balanced-unbalanced-gradually rebalanced＇ pattern in the process. （2） China＇s rapid economic growth experienced a spatial shift from the coastal areas to the the inland areas. Most advanced cities in mid-western China can be roughly categorized into regional hub cities and resource-dependent cities. （3） Hot spots in China＇s economy moved northward and westward. The interactions between cities and prefectures became weaker in Eastern China, while cities and prefectures in Central and Western China were still at the stage of individual development, with limited effect on the surrounding cities. （4） While the overall growth rate of China＇s economy has gradually slowed down during the past two decades, the growth rate of cities and prefectures in Central and Western China was much faster than those in coastal areas. （5） Areas rich in resources, such as Xinjiang and Inner Mongolia, have become the new hot spots of economic growth in recent years. For these regions, however, more attention needs to be paid to their unbalanced industrial structures and the lagging social d展开更多
Using counties as the basic analysis unit,this study established an evaluation index system for farmland function(FF)from economic,social,and ecological perspectives.The method combining entropy weighting and multiple...Using counties as the basic analysis unit,this study established an evaluation index system for farmland function(FF)from economic,social,and ecological perspectives.The method combining entropy weighting and multiple correlation coefficient weighting was adopted to determine the weights,and the FF indices were calculated for each county.Sub-sequently,the spatio-temporal characteristics of farmland function evolution(FFE)were an-alyzed and the coupled relationships between the sub-functions were explored based on a coupling coordination model.At the same time,the dynamic mechanism of FFE was quanti-tatively analyzed using a spatial econometric regression analysis method.The following ma-jor conclusions were drawn:(1)The farmland economic function generally exhibited a de-clining trend during 1990-2010,and it is essential to point out that it was stronger in under-developed and agriculture-dominated counties,while it continuously weakened in developed areas.Farmland social function decreased in 60.29%of the counties,whereas some counties which were mostly located in north of Zhengzhou and west of Dezhou and Cangzhou,Yantai,and Weihai,clearly increased.A dramatic decline in farmland ecological function occurred around Beijing,Tianjin,and Jinan.Areas located in the northern part of Henan Province and the central part of Shandong Province saw an increase in ecological function.(2)There was a significant spatial difference in the coupling degree and coordination degree of the sub-functions,and the decoupling phenomenon highlighted this.The changes in social func-tion and ecological function lagged behind economic function in developed areas,but these were highly coupled in some underdeveloped areas.(3)FFE in the Huang-Huai-Hai Plain(HHHP)is resulted from the comprehensive effects of regional basic conditions and external driving factors.Furthermore,the transitions of population and industry under urbanization and industrialization played a decisive role in the evolution intensity and direction of farmland sub-systems,展开更多
基金CAS Action-plan for West Development,No.KZCX2-XB2-06-03National Key Project of Scientific andTechnical Supporting Programs,No.2006BAC08B00
文摘Supported by MSS images in the mid and late 1970s,TM images in the early 1990s and TM/ETM images in 2004,grassland degradation in the＂Three-River Headwaters＂region （TRH region）was interpreted through analysis on RS images in two time series,then the spatial and temporal characteristics of grassland degradation in the TRH region were analyzed since the 1970s.The results showed that grassland degradation in the TRH region was a continuous change process which had large affected area and long time scale,and rapidly strengthen phenomenon did not exist in the 1990s as a whole.Grassland degradation pattern in the TRH region took shape initially in the mid and late 1970s.Since the 1970s,this degradation process has taken place continuously,obviously characterizing different rules in different regions.In humid and semi-humid meadow region,grassland firstly fragmentized, then vegetation coverage decreased continuously,and finally＂black-soil-patch＂degraded grassland was formed.But in semi-arid and arid steppe region,the vegetation coverage decreased continuously,and finally desertification was formed.Because grassland degradation had obviously regional differences in the TRH region,it could be regionalized into 7 zones, and each zone had different characteristics in type,grade,scale and time process of grassland degradation.
基金supported by the CAMS Innovation Fund for Medical Sciences(2021-I2M-1-011,2021-12M-1-046)。
文摘Largely due to population ageing,the cancer burden from older people has been rising,which imposed considerable pressure on current Chinese healthcare system.We provide comprehensive information about cancer burden of Chinese older people based on the most recent data from National Central Cancer Registry of China.The logarithmic linear regression was used to project the current cancer burden in 2022,and Joinpoint regression was used for temporal trend analysis from 2000 to 2017.We also estimated cancer statistics of older people in the US,Japan and the Republic of Korea for comparisons.It is estimated that 2.79 million cases and 1.94 million deaths occur for Chinese older people,representing 55.8%and 68.2%of cases and deaths in all population in 2022.The overall cancer incidence rate gradually increased among older women,while the mortality rates declined for both sexes.Notably,approximately 10.0%of all cases and 17.7%of all deaths are from people aged over 80 years,and cancer incidence and mortality in this age group showed upward trends for women.Lung cancer and digestive cancers are the leading cancer types for Chinese older people.Compared with other countries,China has lower incidence rates but higher mortality rates for older people.The rapidly growing burden of prostate cancer,breast cancer,colorectal cancer,and declines in esophageal cancer,stomach cancer,and liver cancer among older people indicate the cancer pattern in China is being in a transition stage to that in developed countries.Our findings imply that it should be the national health priority to meet the growing demands for cancer diagnosis,treatment and care services from the older people as the rapid population ageing in next few decades.
基金supported jointly by the National Natural Science Foundation of China (Grant No.40975039),GYHY201006018the Key Technologies R&D Program (Grant No. 2009BAC51B00)
文摘Daily maximum/minimum temperatures and relative humidity records from 510 stations in China for the period 1960–2008 were used to investigate geographical patterns and temporal variations of heatwave （HW） events. Dry and wet HW events were compared by different definitions. Regionally, both dry and wet HW events are commonly located in southeastern China in the monsoon area, with neither type occurring in the northeast part of Northeast China and Southwest China, while the north-northwest region of the country experiences dry HW events and a few wet HW events. In the southeast of the country, site dry HW events occurred from April to September and mostly in June, while site wet HW events occurred from April to October and mostly in September. In total, 163 regional wet HW events were identified. The ten longest regional wet HW events lasted for more than 20 days, while the mean duration for 163 events was about 11 days. For the top ten events, six occurred after the 1990s, compared with four before this time. Global surface warming was clear since 1979, but the frequency and severity of regional wet HW events were relatively low in the 1980s, increasing remarkably since the 1990s. Possible reasons for this might be the strong interdecadal and interannual variations in regional atmospheric circulations, as well as water transport related directly to temperature contrasts in different regions, rather than global-mean temperature changes.
基金National Natural Science Foundation of China, No.41171107
文摘As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China＇s economy. However, little research has grasped the essence of the economic development stage and the spatio-temporal evolution process at the prefecture level; this may lead to biased policies and their ineffective implementations. Based on Chenery＇s economic development theory, this paper identifies China＇s economic development stages at both national and prefectural levels. Both the Global Moran I index and the Getis-Ord Gi＊ index are employed to investigate the spatio-temporal evolution of China＇s economic development from 1990 to 2010. Major conclusions can be drawn as follows. （1） China＇s economic development is generally in the state of agglomeration. It entered the Primary Production Stage in 1990, and the Middle Industrialized Stage in 2010, with a ＇balanced-unbalanced-gradually rebalanced＇ pattern in the process. （2） China＇s rapid economic growth experienced a spatial shift from the coastal areas to the the inland areas. Most advanced cities in mid-western China can be roughly categorized into regional hub cities and resource-dependent cities. （3） Hot spots in China＇s economy moved northward and westward. The interactions between cities and prefectures became weaker in Eastern China, while cities and prefectures in Central and Western China were still at the stage of individual development, with limited effect on the surrounding cities. （4） While the overall growth rate of China＇s economy has gradually slowed down during the past two decades, the growth rate of cities and prefectures in Central and Western China was much faster than those in coastal areas. （5） Areas rich in resources, such as Xinjiang and Inner Mongolia, have become the new hot spots of economic growth in recent years. For these regions, however, more attention needs to be paid to their unbalanced industrial structures and the lagging social d
基金Key Program of National Natural Science Foundation of China,No.41731286
文摘Using counties as the basic analysis unit,this study established an evaluation index system for farmland function(FF)from economic,social,and ecological perspectives.The method combining entropy weighting and multiple correlation coefficient weighting was adopted to determine the weights,and the FF indices were calculated for each county.Sub-sequently,the spatio-temporal characteristics of farmland function evolution(FFE)were an-alyzed and the coupled relationships between the sub-functions were explored based on a coupling coordination model.At the same time,the dynamic mechanism of FFE was quanti-tatively analyzed using a spatial econometric regression analysis method.The following ma-jor conclusions were drawn:(1)The farmland economic function generally exhibited a de-clining trend during 1990-2010,and it is essential to point out that it was stronger in under-developed and agriculture-dominated counties,while it continuously weakened in developed areas.Farmland social function decreased in 60.29%of the counties,whereas some counties which were mostly located in north of Zhengzhou and west of Dezhou and Cangzhou,Yantai,and Weihai,clearly increased.A dramatic decline in farmland ecological function occurred around Beijing,Tianjin,and Jinan.Areas located in the northern part of Henan Province and the central part of Shandong Province saw an increase in ecological function.(2)There was a significant spatial difference in the coupling degree and coordination degree of the sub-functions,and the decoupling phenomenon highlighted this.The changes in social func-tion and ecological function lagged behind economic function in developed areas,but these were highly coupled in some underdeveloped areas.(3)FFE in the Huang-Huai-Hai Plain(HHHP)is resulted from the comprehensive effects of regional basic conditions and external driving factors.Furthermore,the transitions of population and industry under urbanization and industrialization played a decisive role in the evolution intensity and direction of farmland sub-systems,
