There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occu...There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occupation and supplement are unavoidable.It not only leads to the variation of cropland area,but also makes the light-temperature potential productivity per unit area different due to regional climate differentiation,therefore impacts the total potential productivity and food output eventually.So,it is necessary to analyze the climate differentiation between occupation and supplement cropland areas and to study its impact on total potential productivity,which is significant to reasonably develop natural resources and instruct agricultural arrangement.This study firstly discussed the variation and distribution of occupation and supplement croplands in China from 2000 to 2008,then analyzed the climate differentiation between occupation and supplement cropland areas and its effect on light-temperature potential productivity.The results demonstrate:1) From 2000 to 2008,the cropland variation presented occupation in the south and supplement in the north,but overall decreased.Supplement cropland was mainly from ecological reclamation(77.78%) and was mainly distributed in Northeast China and Northwest China with poor climatic and natural conditions.Occupation cropland was mainly used for construction(52.88%) and ecological restoration(44.78%) purposes,and was mainly distributed in the Huang-Huai-Hai Plain,and the middle and lower reaches of the Changjiang(Yangtze) River with better climatic and natural conditions.2) The climate conditions were quite different in supplement and occupation cropland areas.The annual precipitation,annual accumulated temperature and average annual temperature were lower in the supplement cropland area,and its average po-tential productivity per unit was only 62% of occupation cropland area,which was the main reason for the decrease of total potential productivity.3) Cropland occupation and supplement led to the variation of total potential productivity and its spatial distribution.The productivity decreased in the south and increased in the north,but had a net loss of 4.38315×107 t in the whole country.The increase of cropland area was at the cost of reclaiming natural forest and grassland resources,and destroying natural ecological environment,while the decrease of cropland area was mainly due to a lot of cropland occupied by urban-rural construction,which threatened the sustainable use of cropland resources.展开更多
Objective： To analyze the crash and injury data in forensic medicine for years of 2004-2007. Methods： A sample of over 567 accident cases （9 pedestrians, 116 bicyclists, and 442 motor vehicle occupants） was consi...Objective： To analyze the crash and injury data in forensic medicine for years of 2004-2007. Methods： A sample of over 567 accident cases （9 pedestrians, 116 bicyclists, and 442 motor vehicle occupants） was considered from the Department of Forensic Medicine, Shahid Bahonar University of Kerman, involving drivers of all ages and covering a four-year period. Results： The male fatality rates were significantly higher than female ones. The groups at 15-30 years old and at 30-55 years old had the first and second highest numbers of deaths （40% and 34%, respectively）. There were substantial differences in distribution of injuries in motor vehicle occupants and pedestrians and bicyclists. Among motor vehicle occupants, there were more head injuries, such as skull fracture, brain contusion, subdural haemorrhage, and epidural haemorrhage. Nearly 77% of fatalities occurred during 08：00-22：00 in Sirjan. Internal bleeding was also higher in motor vehicle occupants. Pedestrians and bicyclists also had head injuries frequently. Conclusions： In spite of reduction of road traffic fatalities in Sirjan in 2007, it is still one of the cities with high road traffic fatality in the world. These results underline the importance of preventive strategies in transportation, suggesting that different methods are necessary to reduce fatalities of various traffic participants.展开更多
The snow leopard(Panthera uncia)inhabits a human-altered alpine landscape and is often tolerated by residents in regions where the dominant religion is Tibetan Buddhism,including in Qomolangma NNR on the northern side...The snow leopard(Panthera uncia)inhabits a human-altered alpine landscape and is often tolerated by residents in regions where the dominant religion is Tibetan Buddhism,including in Qomolangma NNR on the northern side of the Chinese Himalayas.Despite these positive attitudes,many decades of rapid economic development and population growth can cause increasing disturbance to the snow leopards,altering their habitat use patterns and ultimately impacting their conservation.We adopted a dynamic landscape ecology perspective and used multiscale technique and occupancy model to better understand snow leopard habitat use and coexistence with humans in an 825 km^(2) communal landscape.We ranked eight hypothetical models containing potential natural and anthropogenic drivers of habitat use and compared them between summer and winter seasons within a year.HABITAT was the optimal model in winter,whereas ANTHROPOGENIC INFLUENCE was the top ranking in summer(AICc_(w)≤2).Overall,model performance was better in the winter than in the summer,suggesting that perhaps some latent summer covariates were not measured.Among the individual variables,terrain ruggedness strongly affected snow leopard habitat use in the winter,but not in the summer.Univariate modeling suggested snow leopards prefer to use rugged land in winter with a broad scale(4000 m focal radius)but with a lesser scale in summer(30 m);Snow leopards preferred habitat with a slope of 22°at a scale of 1000 m throughout both seasons,which is possibly correlated with prey occurrence.Furthermore,all covariates mentioned above showed inextricable ties with human activities(presence of settlements and grazing intensity).Our findings show that multiple sources of anthropogenic activity have complex connections with snow leopard habitat use,even under low human density when anthropogenic activities are sparsely distributed across a vast landscape.This study is also valuable for habitat use research in the future,especially regarding covariate selection for finite sample sizes in inaccessible terrain.展开更多
基金Under the auspices of Knowledge Innovation Programs of Chinese Academy of Sciences (No KSCX1-YW-09-01)
文摘There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occupation and supplement are unavoidable.It not only leads to the variation of cropland area,but also makes the light-temperature potential productivity per unit area different due to regional climate differentiation,therefore impacts the total potential productivity and food output eventually.So,it is necessary to analyze the climate differentiation between occupation and supplement cropland areas and to study its impact on total potential productivity,which is significant to reasonably develop natural resources and instruct agricultural arrangement.This study firstly discussed the variation and distribution of occupation and supplement croplands in China from 2000 to 2008,then analyzed the climate differentiation between occupation and supplement cropland areas and its effect on light-temperature potential productivity.The results demonstrate:1) From 2000 to 2008,the cropland variation presented occupation in the south and supplement in the north,but overall decreased.Supplement cropland was mainly from ecological reclamation(77.78%) and was mainly distributed in Northeast China and Northwest China with poor climatic and natural conditions.Occupation cropland was mainly used for construction(52.88%) and ecological restoration(44.78%) purposes,and was mainly distributed in the Huang-Huai-Hai Plain,and the middle and lower reaches of the Changjiang(Yangtze) River with better climatic and natural conditions.2) The climate conditions were quite different in supplement and occupation cropland areas.The annual precipitation,annual accumulated temperature and average annual temperature were lower in the supplement cropland area,and its average po-tential productivity per unit was only 62% of occupation cropland area,which was the main reason for the decrease of total potential productivity.3) Cropland occupation and supplement led to the variation of total potential productivity and its spatial distribution.The productivity decreased in the south and increased in the north,but had a net loss of 4.38315×107 t in the whole country.The increase of cropland area was at the cost of reclaiming natural forest and grassland resources,and destroying natural ecological environment,while the decrease of cropland area was mainly due to a lot of cropland occupied by urban-rural construction,which threatened the sustainable use of cropland resources.
文摘Objective： To analyze the crash and injury data in forensic medicine for years of 2004-2007. Methods： A sample of over 567 accident cases （9 pedestrians, 116 bicyclists, and 442 motor vehicle occupants） was considered from the Department of Forensic Medicine, Shahid Bahonar University of Kerman, involving drivers of all ages and covering a four-year period. Results： The male fatality rates were significantly higher than female ones. The groups at 15-30 years old and at 30-55 years old had the first and second highest numbers of deaths （40% and 34%, respectively）. There were substantial differences in distribution of injuries in motor vehicle occupants and pedestrians and bicyclists. Among motor vehicle occupants, there were more head injuries, such as skull fracture, brain contusion, subdural haemorrhage, and epidural haemorrhage. Nearly 77% of fatalities occurred during 08：00-22：00 in Sirjan. Internal bleeding was also higher in motor vehicle occupants. Pedestrians and bicyclists also had head injuries frequently. Conclusions： In spite of reduction of road traffic fatalities in Sirjan in 2007, it is still one of the cities with high road traffic fatality in the world. These results underline the importance of preventive strategies in transportation, suggesting that different methods are necessary to reduce fatalities of various traffic participants.
文摘The snow leopard(Panthera uncia)inhabits a human-altered alpine landscape and is often tolerated by residents in regions where the dominant religion is Tibetan Buddhism,including in Qomolangma NNR on the northern side of the Chinese Himalayas.Despite these positive attitudes,many decades of rapid economic development and population growth can cause increasing disturbance to the snow leopards,altering their habitat use patterns and ultimately impacting their conservation.We adopted a dynamic landscape ecology perspective and used multiscale technique and occupancy model to better understand snow leopard habitat use and coexistence with humans in an 825 km^(2) communal landscape.We ranked eight hypothetical models containing potential natural and anthropogenic drivers of habitat use and compared them between summer and winter seasons within a year.HABITAT was the optimal model in winter,whereas ANTHROPOGENIC INFLUENCE was the top ranking in summer(AICc_(w)≤2).Overall,model performance was better in the winter than in the summer,suggesting that perhaps some latent summer covariates were not measured.Among the individual variables,terrain ruggedness strongly affected snow leopard habitat use in the winter,but not in the summer.Univariate modeling suggested snow leopards prefer to use rugged land in winter with a broad scale(4000 m focal radius)but with a lesser scale in summer(30 m);Snow leopards preferred habitat with a slope of 22°at a scale of 1000 m throughout both seasons,which is possibly correlated with prey occurrence.Furthermore,all covariates mentioned above showed inextricable ties with human activities(presence of settlements and grazing intensity).Our findings show that multiple sources of anthropogenic activity have complex connections with snow leopard habitat use,even under low human density when anthropogenic activities are sparsely distributed across a vast landscape.This study is also valuable for habitat use research in the future,especially regarding covariate selection for finite sample sizes in inaccessible terrain.
