Salt lakes,the main source of trona resources in China, are widely distributed on the Inner Mongolian Plateau. Their characteristics are large in number, various in type, and short in salt-forming stage, especially th...Salt lakes,the main source of trona resources in China, are widely distributed on the Inner Mongolian Plateau. Their characteristics are large in number, various in type, and short in salt-forming stage, especially their considerable number is well-known at home and abroad. The paper discusses the physical constituents, hydrochemical features, classification, formation, evolution, and salt-forming regularities of salt lakes through analyzing their distribution, lacustrine deposits and salt-forming conditions.展开更多
The mid-Holocene in China is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorpholog...The mid-Holocene in China is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorphologic and lithological evidence from the Alashan Plateau, part of the Mongolian Plateau, that indicates strong lake desiccation during the mid-Holocene. High resolution pollen data from Zhuyeze Lake, at the present summer monsoon margin, is also presented. These data show that present lakes and wetlands in the Juyanze Lake basin west of the Badain Jaran desert, in the Zhuyeze Lake basin between the Badain Jaran and Tengger deserts, and in lakes in the eastern Tengger desert, dried or experienced low lake levels in the mid-Holocene around 5000—7000 cal yr BP. Pollen data further indicate that the vegetation cover declined in both the local areas and in the Qilian Mountains, suggesting the climate was drier than that associated with the present Asian summer monsoon. This mid-Holocene drought interval was present throughout a quite large region of the south Inner Mongolian Plateau. The period was also probably colder, at least in the high Asian plateaus and mountains.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
Grassland ecosystems in cold regions are typical of short growing seasons and limited primary productivity,rendering soil microorganisms as major ecosystem engineers in governing biogeochemical cycling.Climate warming...Grassland ecosystems in cold regions are typical of short growing seasons and limited primary productivity,rendering soil microorganisms as major ecosystem engineers in governing biogeochemical cycling.Climate warming and extensive livestock grazing have dramatically influenced soil microbial diversity and function in grassland worldwide,but it remains elusive how functional microbial communities exist and respond to global changes.Here,we present a review to highlight similarities and differences in soil functional microbial communities between alpine grasslands in the Qinghai-Tibet Plateau and temperate grasslands in the Inner Mongolian Plateau,both of which are major plateaus in China,but differ substantially in geography.We show that many specialized functional groups thrive under harsh conditions,exhibiting a high functional diversity.Their community compositions mirror the heterogeneity and complexity of grassland soils.Moreover,functional microbial responses to environmental changes have been extremely variable,with few consistent patterns across both plateaus.Because we identify a lack of technical standardization that prevents in-depth comparative studies for functional microbial communities,we conclude the review by outlining several research gaps that need to be filled in future studies.展开更多
文摘Salt lakes,the main source of trona resources in China, are widely distributed on the Inner Mongolian Plateau. Their characteristics are large in number, various in type, and short in salt-forming stage, especially their considerable number is well-known at home and abroad. The paper discusses the physical constituents, hydrochemical features, classification, formation, evolution, and salt-forming regularities of salt lakes through analyzing their distribution, lacustrine deposits and salt-forming conditions.
基金supported by the National Natural Science Foundation of China(Grant No.40125001)the Hundred Talent Project of CAS and the International Collaboration Project(Grant No.2002CB714004).
文摘The mid-Holocene in China is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorphologic and lithological evidence from the Alashan Plateau, part of the Mongolian Plateau, that indicates strong lake desiccation during the mid-Holocene. High resolution pollen data from Zhuyeze Lake, at the present summer monsoon margin, is also presented. These data show that present lakes and wetlands in the Juyanze Lake basin west of the Badain Jaran desert, in the Zhuyeze Lake basin between the Badain Jaran and Tengger deserts, and in lakes in the eastern Tengger desert, dried or experienced low lake levels in the mid-Holocene around 5000—7000 cal yr BP. Pollen data further indicate that the vegetation cover declined in both the local areas and in the Qilian Mountains, suggesting the climate was drier than that associated with the present Asian summer monsoon. This mid-Holocene drought interval was present throughout a quite large region of the south Inner Mongolian Plateau. The period was also probably colder, at least in the high Asian plateaus and mountains.
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.
基金supported by the Outstanding Youth Program of the National Natural Science Foundation of China(41825016)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0503).
文摘Grassland ecosystems in cold regions are typical of short growing seasons and limited primary productivity,rendering soil microorganisms as major ecosystem engineers in governing biogeochemical cycling.Climate warming and extensive livestock grazing have dramatically influenced soil microbial diversity and function in grassland worldwide,but it remains elusive how functional microbial communities exist and respond to global changes.Here,we present a review to highlight similarities and differences in soil functional microbial communities between alpine grasslands in the Qinghai-Tibet Plateau and temperate grasslands in the Inner Mongolian Plateau,both of which are major plateaus in China,but differ substantially in geography.We show that many specialized functional groups thrive under harsh conditions,exhibiting a high functional diversity.Their community compositions mirror the heterogeneity and complexity of grassland soils.Moreover,functional microbial responses to environmental changes have been extremely variable,with few consistent patterns across both plateaus.Because we identify a lack of technical standardization that prevents in-depth comparative studies for functional microbial communities,we conclude the review by outlining several research gaps that need to be filled in future studies.
