Emergency resources are an important basis of effective emergency response. But there are many disadvantages of the Chinese traditional material reserve method in which the resources are separately reserved in differe...Emergency resources are an important basis of effective emergency response. But there are many disadvantages of the Chinese traditional material reserve method in which the resources are separately reserved in different regions and sections according to the kinds of disasters. So there comes the Multi-formal and Information-based Emergency Resource Reserve System (MIERRS) in China. The reserve body and method change from the single into the multiple forms, that is, the main reserve body changes from the single government agency into the organizations combining with the military, enterprise and society, and the reserve method changes from single material reserve into the reserve combining with market reserve, talents and technology reserve, and production capacity reserve. The content of the reserve change from material to information means to develop the Emergency Resource Management Information System realizing real-time control of resource characteristics and relevant reserve information. The MIERRS leads to a reserve system with rapid response and flexible schedule. It provides a convenient platform for resource sharing, thus avoiding duplication and waste, improving the utilization of resources, reducing the reserve loss and optimizing the structure of resource reserve.展开更多
The anatomical features of leaves in 11 species of plantsgrowninatemperaturegradientandatemperature+CO_(2)gradient were studied.The palisade parenchyma thickness,the spongy parenchyma thickness and the total leaf thic...The anatomical features of leaves in 11 species of plantsgrowninatemperaturegradientandatemperature+CO_(2)gradient were studied.The palisade parenchyma thickness,the spongy parenchyma thickness and the total leaf thickness were measured and analyzed to investigate the effects of ele-vated temperature and CO_(2)on the anatomical characteristics of the leaves.Our results show that with the increase of temperature,the leaf thickness of C_(4)species increased while the leaf thickness of C_(3)species showed no constant changes.With increased CO_(2),seven out of nine C_(3)species exhibited increased total leaf thickness.In C_(4)species,leaf thickness decreased.As for the trend on the multi-grades,the plants exhibited linear or non-linear changes.With the increase of temperature or both temperature and CO_(2)for the 11 species investigated,leaf thickness varied greatly in different plants(species)and even in different branches on the same plant.These results demonstrated that the effect of increasing CO_(2)and temperature on the anatomical features of the leaves were species-specific.Since plant structures are correlated with plant functions,the changes in leaf anatomical characteristics in elevated temperature and CO_(2)may lead to functional differences.展开更多
Variations in vegetation activity during the past 18 years in China were investigated using the normalized difference vegetation index (NDVI) derived from the 3rd generation time series dataset of NOAA-AVHRR from 1982...Variations in vegetation activity during the past 18 years in China were investigated using the normalized difference vegetation index (NDVI) derived from the 3rd generation time series dataset of NOAA-AVHRR from 1982 to 1999. In order to eliminate the effects of non-vegetation factors, we characterized areas with NDVI < 0.1 as sparsely vegetated areas and areas with NDVI ≥ 0.1 as vegetated areas. The results showed that increasing NDVI trends were evident, to varying extents, in almost all regions in China in the 18 years, indicating that vegetation activity has been rising in recent years in these regions. Compared to the early 1980s, the vegetated area increased by 3.5% by the late 1990s, while the sparsely vegetated area declined by 18.1% in the same period. The national total mean annual NDVI increased by 7.4% during the study period. Extended growing seasons and increased plant growth rates ac-counted for the bulk of these increases, while increases in temperature and summer rainfall, and strengthening agricultural activity were also likely important factors. NDVI changes in China ex-hibited relatively large spatial heterogeneity; the eastern coastal regions experienced declining or indiscernibly rising trends, while agricultural regions and western China experienced marked increases. Such a pattern was due primarily to urbanization, agricultural activity, regional climate characteristics, and different vegetation responses to regional climate changes.展开更多
Understanding the patterns of forage quantity and quality and investigating the factors influencing these patterns are essential for the development of animal husbandry.However,there is very little field evidence focu...Understanding the patterns of forage quantity and quality and investigating the factors influencing these patterns are essential for the development of animal husbandry.However,there is very little field evidence focused on these issues at a large spatial scale.In the current study,we analyzed forage quantity and quality at 177 sites distributed in all the major grassland types across China,and explored the relationship between forage quantity and quality based on consistent sampling protocols.We also investigated potential factors influencing forage quality patterns across China.Our study indicates the Tibetan grasslands had both higher quantity and quality forage than the Inner Mongolian grasslands,and alpine meadow had the best quantity and quality forage because of the meadow's high productivity and the crude protein and nitrogen free extract content of the meadow forage.For the main vegetation formations,Kobresia tibetica meadows and Achnatherum splendens steppes had the highest quantity,while Kobresia pygmaea meadows and Kobresia humilis meadows had the best quality.We also found that although environmental factors,such as temperature and soil fertility,could affect physiological processes and so influence forage quality,the large scale patterns of change were mainly a result of the differences in vegetation types.Finally,we reported a negative relationship between forage quantity and quality:higher forage quantity means more crude fiber but less ether extract and crude protein.These findings improve our understanding on the spatial patterns of forage quantity and quality,and provide solid evidence related to the future development of animal husbandry.展开更多
Knowledge of the leaf anatomy of grassland plants is crucial for understanding how these plants adapt to the environment. Tibetan alpine grasslands and Inner Mongolian temperate grasslands are two major grassland type...Knowledge of the leaf anatomy of grassland plants is crucial for understanding how these plants adapt to the environment. Tibetan alpine grasslands and Inner Mongolian temperate grasslands are two major grassland types in northern China. Tibetan alpine grasslands occur in high-altitude regions where the low temperatures limit plant growth. Inner Mongolian temperate grasslands are found in arid regions where moisture is the limiting factor. Few comparative studies concerning the leaf anatomy of grassland plants of the Tibetan Plateau and Inner Mongolian Plateau have been conducted. We examined leaf characteristics at 71 sites and among 65 species, across the alpine grasslands of the Tibetan Plateau and the temperate grasslands of the Inner Mongolian Plateau. We compared the leaf structures of plants with different life forms and taxonomies, and their adaptation to arid or cold environments. We explored relationships among leaf features and the effects of climatic factors (i.e., growing season temperature and precipitation) on leaf characteristics. Our results showed that (i) there were significant differences in leaf anatomy between Tibetan alpine and Inner Mongolian temperate grasslands. Except for mesophyll cell density, the values obtained for thickness of leaf tissue, surface area and volume of mesophyll cells were larger on the Tibetan Plateau than on the Inner Mongolian Plateau. (ii) Within the same family or genus, leaf anatomy showed significant differences between two regions, and trends were consistent with those of whole species. (iii) Leaf anatomy of woody and herbaceous plants also showed significant differences between the regions. Except for mesophyll cell density, the values obtained for the thickness of leaf tissue, and the surface area and volume of mesophyll cells were larger in herbaceous than in woody plants. (iv) Leaf anatomical traits changed accordingly. Total leaf thickness, thicknesses of lower and upper epidermal cells, and surface area and volume of mesophyll cells were positively correlated, while mesophyll cell density was negatively associated with those traits. (v) Growing season temperature had stronger effects on leaf anatomy than growing season precipitation. Although the communities in Tibetan and Inner Mongolian grasslands were similar in appearance, leaf anatomy differed; this was probably due to the combined effects of evolutionary adaptation of plants to environment and environmental stress induced by climatic factors.展开更多
With a coverage of 30% of the Earth＇s land area, forest biomes play an important role in global carbon （C） cycling and C management , There are two main reasons for this. First, a huge amount of C is stored in fore...With a coverage of 30% of the Earth＇s land area, forest biomes play an important role in global carbon （C） cycling and C management , There are two main reasons for this. First, a huge amount of C is stored in forest live biomass.展开更多
Electron microscopy(EM) should be used in the front line for detection of agents in emergencies and bioterrorism,on accounts of its speed and accuracy.However,the number of EM diagnostic laboratories has decreased con...Electron microscopy(EM) should be used in the front line for detection of agents in emergencies and bioterrorism,on accounts of its speed and accuracy.However,the number of EM diagnostic laboratories has decreased considerably and an increasing number of people encounter difficulties with EM results.Therefore,the research on viral structure and morphology has become important in EM diagnostic practice.EM has several technological advantages,and should be a fundamental tool in clinical diagnosis of viruses,particularly when agents are unknown or unsuspected.In this article,we review the historical contribution of EM to virology,and its use in virus differentiation,localization of specific virus antigens,virus-cell interaction,and viral morphogenesis.It is essential that EM investigations are based on clinical and comprehensive pathogenesis data from light or confocal microscopy.Furthermore,avoidance of artifacts or false results is necessary to exploit fully the advantages while minimizing its limitations.展开更多
基金China National Natural Science Foundation Funded Project (Grant No. 70771073)
文摘Emergency resources are an important basis of effective emergency response. But there are many disadvantages of the Chinese traditional material reserve method in which the resources are separately reserved in different regions and sections according to the kinds of disasters. So there comes the Multi-formal and Information-based Emergency Resource Reserve System (MIERRS) in China. The reserve body and method change from the single into the multiple forms, that is, the main reserve body changes from the single government agency into the organizations combining with the military, enterprise and society, and the reserve method changes from single material reserve into the reserve combining with market reserve, talents and technology reserve, and production capacity reserve. The content of the reserve change from material to information means to develop the Emergency Resource Management Information System realizing real-time control of resource characteristics and relevant reserve information. The MIERRS leads to a reserve system with rapid response and flexible schedule. It provides a convenient platform for resource sharing, thus avoiding duplication and waste, improving the utilization of resources, reducing the reserve loss and optimizing the structure of resource reserve.
文摘The anatomical features of leaves in 11 species of plantsgrowninatemperaturegradientandatemperature+CO_(2)gradient were studied.The palisade parenchyma thickness,the spongy parenchyma thickness and the total leaf thickness were measured and analyzed to investigate the effects of ele-vated temperature and CO_(2)on the anatomical characteristics of the leaves.Our results show that with the increase of temperature,the leaf thickness of C_(4)species increased while the leaf thickness of C_(3)species showed no constant changes.With increased CO_(2),seven out of nine C_(3)species exhibited increased total leaf thickness.In C_(4)species,leaf thickness decreased.As for the trend on the multi-grades,the plants exhibited linear or non-linear changes.With the increase of temperature or both temperature and CO_(2)for the 11 species investigated,leaf thickness varied greatly in different plants(species)and even in different branches on the same plant.These results demonstrated that the effect of increasing CO_(2)and temperature on the anatomical features of the leaves were species-specific.Since plant structures are correlated with plant functions,the changes in leaf anatomical characteristics in elevated temperature and CO_(2)may lead to functional differences.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.40024101&90211016).
文摘Variations in vegetation activity during the past 18 years in China were investigated using the normalized difference vegetation index (NDVI) derived from the 3rd generation time series dataset of NOAA-AVHRR from 1982 to 1999. In order to eliminate the effects of non-vegetation factors, we characterized areas with NDVI < 0.1 as sparsely vegetated areas and areas with NDVI ≥ 0.1 as vegetated areas. The results showed that increasing NDVI trends were evident, to varying extents, in almost all regions in China in the 18 years, indicating that vegetation activity has been rising in recent years in these regions. Compared to the early 1980s, the vegetated area increased by 3.5% by the late 1990s, while the sparsely vegetated area declined by 18.1% in the same period. The national total mean annual NDVI increased by 7.4% during the study period. Extended growing seasons and increased plant growth rates ac-counted for the bulk of these increases, while increases in temperature and summer rainfall, and strengthening agricultural activity were also likely important factors. NDVI changes in China ex-hibited relatively large spatial heterogeneity; the eastern coastal regions experienced declining or indiscernibly rising trends, while agricultural regions and western China experienced marked increases. Such a pattern was due primarily to urbanization, agricultural activity, regional climate characteristics, and different vegetation responses to regional climate changes.
基金supported by the National Natural Science Foundation of China (31025005 and 31021001)the Program of "One Hundred Talented People" of the Chinese Academy of Sciences (KSCX2-YW-Z-0806)
文摘Understanding the patterns of forage quantity and quality and investigating the factors influencing these patterns are essential for the development of animal husbandry.However,there is very little field evidence focused on these issues at a large spatial scale.In the current study,we analyzed forage quantity and quality at 177 sites distributed in all the major grassland types across China,and explored the relationship between forage quantity and quality based on consistent sampling protocols.We also investigated potential factors influencing forage quality patterns across China.Our study indicates the Tibetan grasslands had both higher quantity and quality forage than the Inner Mongolian grasslands,and alpine meadow had the best quantity and quality forage because of the meadow's high productivity and the crude protein and nitrogen free extract content of the meadow forage.For the main vegetation formations,Kobresia tibetica meadows and Achnatherum splendens steppes had the highest quantity,while Kobresia pygmaea meadows and Kobresia humilis meadows had the best quality.We also found that although environmental factors,such as temperature and soil fertility,could affect physiological processes and so influence forage quality,the large scale patterns of change were mainly a result of the differences in vegetation types.Finally,we reported a negative relationship between forage quantity and quality:higher forage quantity means more crude fiber but less ether extract and crude protein.These findings improve our understanding on the spatial patterns of forage quantity and quality,and provide solid evidence related to the future development of animal husbandry.
基金supported by the Funds for Creative Research Groups of the National Natural Science Foundation of China (Grant No. 31021001)the Funds of the Chinese Academy of Sciences for Key Topics in Innovation Engineering (Grant No. KSCX2-YW-Z-0806)
文摘Knowledge of the leaf anatomy of grassland plants is crucial for understanding how these plants adapt to the environment. Tibetan alpine grasslands and Inner Mongolian temperate grasslands are two major grassland types in northern China. Tibetan alpine grasslands occur in high-altitude regions where the low temperatures limit plant growth. Inner Mongolian temperate grasslands are found in arid regions where moisture is the limiting factor. Few comparative studies concerning the leaf anatomy of grassland plants of the Tibetan Plateau and Inner Mongolian Plateau have been conducted. We examined leaf characteristics at 71 sites and among 65 species, across the alpine grasslands of the Tibetan Plateau and the temperate grasslands of the Inner Mongolian Plateau. We compared the leaf structures of plants with different life forms and taxonomies, and their adaptation to arid or cold environments. We explored relationships among leaf features and the effects of climatic factors (i.e., growing season temperature and precipitation) on leaf characteristics. Our results showed that (i) there were significant differences in leaf anatomy between Tibetan alpine and Inner Mongolian temperate grasslands. Except for mesophyll cell density, the values obtained for thickness of leaf tissue, surface area and volume of mesophyll cells were larger on the Tibetan Plateau than on the Inner Mongolian Plateau. (ii) Within the same family or genus, leaf anatomy showed significant differences between two regions, and trends were consistent with those of whole species. (iii) Leaf anatomy of woody and herbaceous plants also showed significant differences between the regions. Except for mesophyll cell density, the values obtained for the thickness of leaf tissue, and the surface area and volume of mesophyll cells were larger in herbaceous than in woody plants. (iv) Leaf anatomical traits changed accordingly. Total leaf thickness, thicknesses of lower and upper epidermal cells, and surface area and volume of mesophyll cells were positively correlated, while mesophyll cell density was negatively associated with those traits. (v) Growing season temperature had stronger effects on leaf anatomy than growing season precipitation. Although the communities in Tibetan and Inner Mongolian grasslands were similar in appearance, leaf anatomy differed; this was probably due to the combined effects of evolutionary adaptation of plants to environment and environmental stress induced by climatic factors.
文摘With a coverage of 30% of the Earth＇s land area, forest biomes play an important role in global carbon （C） cycling and C management , There are two main reasons for this. First, a huge amount of C is stored in forest live biomass.
基金supported by the Major Scientific and Technological Special Project of China(2009ZX10004-216)the National Natural Science Foundation of China(81100809,81271417)Fundamental Research Funds for the Central University of China(2011JBM124)
文摘Electron microscopy(EM) should be used in the front line for detection of agents in emergencies and bioterrorism,on accounts of its speed and accuracy.However,the number of EM diagnostic laboratories has decreased considerably and an increasing number of people encounter difficulties with EM results.Therefore,the research on viral structure and morphology has become important in EM diagnostic practice.EM has several technological advantages,and should be a fundamental tool in clinical diagnosis of viruses,particularly when agents are unknown or unsuspected.In this article,we review the historical contribution of EM to virology,and its use in virus differentiation,localization of specific virus antigens,virus-cell interaction,and viral morphogenesis.It is essential that EM investigations are based on clinical and comprehensive pathogenesis data from light or confocal microscopy.Furthermore,avoidance of artifacts or false results is necessary to exploit fully the advantages while minimizing its limitations.
