Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon d...Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon dioxide concentration and thus of water-use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng. in six communities of different habitats in die Xilin River Basin. The foliar delta C-13 values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar delta C-13 Values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis-regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin.展开更多
Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal va...Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal varia-tions of δD and δ^18O in precipitation was conducted in 2007-2008 in the Xilin River Basin, Inner Mongolia in the northern China. The 6D and δ^18O values for 54 precipitation samples range from ＋1.1%o to -34.7%0 and -3.0%0 to -269%0, respectively. This wide range indicates that stable isotopes in precipitation are primarily controlled by differ-ent condensation mechanisms as a function of air temperature and varying sources of vapor. The relationship between δD and δ^18O defined a well constrained line given by δD = 7.896180 ＋ 9.5, which is nearly identical to the Meteoric Water Line in the northern China. The temperature effect is clearly displayed in this area. The results of backward tra-jectory of each precipitation day show that the vapor of the precipitation in cold season （October to March） mainly originates from the west while the moisture source is more complicated in warm season （April to September）. A light precipitation amount effect existes at the precipitation event scale in this area. The vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation with lower d-excesses from a monsoon source from the southeastern China.展开更多
Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol ste...Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol steppe is an important native grassland resource in Inner Mongolia Autonomous Region,China.This study aimed to elucidate the dynamics of the forage-livestock balance in the Xilin Gol steppe during the period 2000–2015.We evaluated the forage production and corresponding livestock carrying capacity(LCC)in the growing seasons of 2000–2015 using remote sensing data and field surveys.The spatiotemporal patterns of the forage-livestock balance were then assessed at regional,city(including city,county and banner),and village scales using statistical and household survey data.The results showed that both forage production and LCC decreased in the Xilin Gol steppe from east to west.During the period 2000–2015,the regional average forage production and corresponding LCC fluctuated without following a distinct trend,but were consistent with the variations in precipitation.The forage-livestock balance varied with time,space,and scale.At the regional scale,steppes were overgrazed in the early 2000s,but a forage-livestock balance or even grazing potential was achieved in other years.At the city scale,approximately half of the region exhibited a"forage-livestock balance"since 2000.However,about half of the region still experienced overgrazing,which mainly located in the southwest sandy zones.Such changes may have been affected by the variations in grassland quality,forage production,compensation payment,and so on.We suggest a location-specific management scheme for grazing constraints,ecological compensation payment,and industry development to aid in harmonizing animal husbandry and environmental restoration,while promoting sustainable development goals by 2030.展开更多
Grassland degradation is influenced by climate change and human activities,and has become a major obstacle for the development of arid and semi-arid areas,posing a series of environmental and socio-economic problems.A...Grassland degradation is influenced by climate change and human activities,and has become a major obstacle for the development of arid and semi-arid areas,posing a series of environmental and socio-economic problems.An in-depth understanding of the inner relations among grassland vegetation dynamics,climate change,and human activities is therefore greatly significant for understanding the variation in regional environmental conditions and predicting future developmental trends.Based on MODIS(moderate resolution imaging spectroradiometer)NDVI(normalized difference vegetation index)data from 2000 to 2020,our objective is to investigate the spatiotemporal changes of NDVI in the Xilin Gol grassland,Inner Mongolia Autonomous Region,China.Combined with 12 natural factors and human activity factors in the same period,the dominant driving factors and their interactions were identified by using the geographic detector model,and multiple scenarios were also simulated to forecast the possible paths of future NDVI changes in this area.The results showed that:(1)in the past 21 a,vegetation cover in the Xilin Gol grassland exhibited an overall increasing trend,and the vegetation restoration(84.53%)area surpassed vegetation degradation area(7.43%);(2)precipitation,wind velocity,and livestock number were the dominant factors affecting NDVI(the explanatory power of these factors exceeded 0.4).The interaction between average annual wind velocity and average annual precipitation,and between average annual precipitation and livestock number greatly affected NDVI changes(the explanatory power of these factors exceeded 0.7).Moreover,the impact of climate change on NDVI was more significant than human activities;and(3)scenario analysis indicated that NDVI in the Xinlin Gol grassland increased under the scenarios of reduced wind velocity,increased precipitation,and ecological protection.In contrast,vegetation coverage restoration in this area was significantly reduced under the scenarios of unfavorable climate conditions and excessive human activities.This study provides a scientific basis for future vegetation restoration and management,ecological environmental construction,and sustainable natural resource utilization in this area.展开更多
This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, Sep...This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, September 27, 1997 and May 23, 2000, respectively. Primarily, 17 sub-class land cover types were recognized, including nine grassland types at community level: F.sibiricum steppe, S.baicalensis steppe, A.chinensis+ forbs steppe, A.chinensis+ bunchgrass steppe, A.chinensis+ Ar.frigida steppe, S.grandis+ A.chinensis steppe, S.grandis+ bunchgrass steppe, S.krylavii steppe, Ar.frigida steppe and eight non-grassland types: active cropland, harvested cropland, urban area, wetland, desertified land, saline and alkaline land, cloud, water body + cloud shadow. To eliminate the classification error existing among different sub-types of the same gross type, the 17 sub-class land cover types were grouped into five gross types: meadow grassland, temperate grassland, desert grassland, cropland and non-grassland. The overall classification accuracy of the five land cover types was 81.0% for 1987, 81.7% for 1991, 80.1% for 1997 and 78.2% for 2000.展开更多
The Xilin Group, composed of the Chenming, Laodaomiaogou, Qianshan and Wuxingzhen formations, is one of the Early Paleozoic terranes in the eastern Songliao Massif, mainly consisting of thick layers of fine clastic an...The Xilin Group, composed of the Chenming, Laodaomiaogou, Qianshan and Wuxingzhen formations, is one of the Early Paleozoic terranes in the eastern Songliao Massif, mainly consisting of thick layers of fine clastic and carbonate rocks. This study presents LA-ICP-MS zircon U-Pb geochronological data for the Laodaomiaogou and Qianshan formations, further constraining their provenance and the Early Paleozoic tectonic evolution of the Songliao Massif on the eastern Central Asian Orogenic Belt. Most zircons from the Laodaomiaogou and Qianshan formations show magmatic oscillatory zoning and high Th/U ratios(0.26–2.41). Zircon U-Pb dating results indicate that the detrital zircons from the silty mudstone of the Laodaomiaogou Formation yield peak ages of 634 Ma, 775 Ma, 820 Ma, 880 Ma and 927 Ma, as well as multi-episodic Archean to Paleoproterozoic and Mesoproterozoic ages(1405–643 Ma), implying its deposition time is younger than ~634 Ma. Furthermore, the occurrence of Early Cambrian fossils indicates that the Laodaomiaogou Formation was deposited during the late stage of the Early Cambrian(~514 Ma). The zircons from the K-bentonite of the Qianshan Formation show four peak ages of 444 Ma, 471 Ma, 489 Ma and 518 Ma and the youngest age peak of 444 ± 4 Ma(n = 6) indicates that the Qianshan Formation was deposited during the Late Ordovician. In addition, the peak ages of the detrital zircons in the silty mudstone of the Qianshan Formation are 472 Ma and 498 Ma, as well as two other concordant points with;Pb/;Pb apparent ages of 1824 Ma and 1985 Ma. The dating results in this study, together with published data, indicate the absence of Pan-African magmatic events in the Songliao Massif prior to the initial deposition of the Xilin Group, in contrast to those distributed widely in the Jiamusi Massif. Taken together, we conclude that the depositional provenance of the Laodaomiaogou and Qianshan formations was derived from the Songliao Massif. Furthermore, the characteristics of the detrital zircon age composition and rock associations indicate that the Laodaomiaogou Formation formed in a passive continental margin environment, in contrast to the Qianshan Formation, which formed in an active continental margin environment. The above results also imply that the Songliao and Jiamusi massifs might not have collided before the Late Ordovician.展开更多
Food safety is an important issue for the development of the national economy and society.Studying regional food supply and demand from the perspective of land resource carrying capacity can provide new references for...Food safety is an important issue for the development of the national economy and society.Studying regional food supply and demand from the perspective of land resource carrying capacity can provide new references for regional resource sustainability.This study uses the data from farmer and herdsmen household questionnaires,statistical data,land use data,and other sources to construct a land resource carrying capacity(LCC)assessment framework,targeting the food supply and demand of residents in representative areas,specifically the typical grassland pastoral areas,sandy pastoral areas and agro-pastoral areas on the Xilin Gol grassland transects.The three food nutritional indicators of calories,protein and fat were selected for analyzing the balance of land resource carrying capacity.We found that:1)Along the Xilin Gol grassland,the main local food supply showed a shift from meat and milk to grains,vegetables and fruits.2)From north to south along the grassland transects,the calorie intake increased gradually,while the intake of protein and fat was highest in pastoral areas and lowest in agricultural areas.3)The overall land resource carrying capacity of the Xilin Gol grassland transects was in a surplus state,but the land carrying capacity of typical grassland pastoral area was higher than the two other types of areas.This study provides an empirical reference for the sustainable development of regional food nutrition.展开更多
The cognition of borderland landscape constitutes an important aspect of understanding the overall geographical order and its internal structure,and is also one of the important contents of the intellectual history of...The cognition of borderland landscape constitutes an important aspect of understanding the overall geographical order and its internal structure,and is also one of the important contents of the intellectual history of frontier thought.It can facilitate us to think about the geographical spatial correlation of the relations between Chinese borderland regions,and further form a comprehensive control of the spatiotemporal structure of a certain borderland region.As an important ecological transition zone in China,the Xilin Gol region of Inner Mongolia is surrounded by unique cultural-geographical landscapes,such as the source of the Luanhe River,Yuan Dadu ruins,Duolun Huizong Temple and etc.It constitutes an important entry point for us to understand the unique landscape across the trans-Great Wall zone,and thus to understand the spatiotemporal correlation of the Yuan-Ming-Qing dynasties,the Tianxia space as a whole and its contemporary symbolic significance.This paper will conduct a specific discussion and interpretation focusing on this main issue,so as to propose corresponding broader perspectives addressing the issue.展开更多
A new rock type of granite, approximate 45 km2 in area and located about 10 km south of Xilinhot, Inner Mongolia, was found in the Sunitezuoqi (or called Su-zuoqi)-Xilinhot tectonic belt and identified as an A-type mi...A new rock type of granite, approximate 45 km2 in area and located about 10 km south of Xilinhot, Inner Mongolia, was found in the Sunitezuoqi (or called Su-zuoqi)-Xilinhot tectonic belt and identified as an A-type mia- rolitic intrusion. The pluton has miarolitic structure and is composed chiefly of perthite, quartz, euhedral albite and potassium feldspar. Various types of textures occur in the pluton, such as perthitie, graphic and myrmekite textures. Only quartz is found in miarolitic cavity. This A-type granite with seagull-shaped REE patterns and obvious negative Eu anomaly (d Eu = 0.24—0.28) is high in SiO2 (76%—77%), K and Na (Na2O + K2O = 7.75%—8.15%) and low in Ca (CaO = 0.20%—0.22%), Fe and Mg. Both petrographical observa-tions and chemical compositions indicate that it is an A-type granite. Zircon SHRIMP U-Pb analyses indicate that this A-type granite was emplaced at 276 2 Ma and coeval with the same type of granites in the adjacent areas. Therefore, it suggests that this pluton was likely formed in a post-orogenic extensional setting and probably related to break-off of sub-ducted slabs in Central Asian Orogenic Belt (CAOB), which indicate that the Sunitezuoqi-Xilinhot belt was tectonically evolved into post-orogenic stage since early Permian.展开更多
The Xilin Gol Complex, consisting of deformed and metamorphosed rocks, was exposed as a large geological unit within the Central Asian Orogenic Belt, but its forming and subsequent deformed and metamorphic time has be...The Xilin Gol Complex, consisting of deformed and metamorphosed rocks, was exposed as a large geological unit within the Central Asian Orogenic Belt, but its forming and subsequent deformed and metamorphic time has been an issue of little consensus. Petrographic analyses and SHRIMP dating on biotite-plagioclase gneiss, one of the ma-jor rocks within the Xilin Gol Complex, in southeast Xilinhot City, Inner Mongolia, China, where the Xilin Gol Complex was identified and named, yield its lower limit age of 437 3 Ma (2s ) by its magmatic zircon SHRIMP U-Pb dating, and an upper limit age of 316 3Ma (2s ), which was constrained by SHRIMP dating of magmatic zircons from adjacent un-deformed garnet-bearing granite which intruded the Com-plex. The Complex was thus determined to be formed and subsequently deformed/metamorphosed from the late Ordovi-cian-early Silurian to the mid-Carboniferous. Consequently, it is not the Precambrian terrane as previously considered by most geologists. More or less, the major rock——biotite- plagioclase gneiss within the Complex is more likely to be Paleozoic fore-arc turbidite formation before metamorphism and intensive deformation, in which the detrital zircons gave sporadic Precambrian ages as old as up to 3.1 Ga. The source of the turbidite formation is multiple, which may be derived either from the North China Craton, or from the South- Mongolia Micro-continent, or probably came from a poten-tial and undiscovered in situ terranes aged 600—800 Ma or even up to ca 3.1 Ga near the Complex.展开更多
文摘Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon dioxide concentration and thus of water-use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng. in six communities of different habitats in die Xilin River Basin. The foliar delta C-13 values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar delta C-13 Values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis-regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin.
基金Under the auspices of Nation Basic Research Program of China(No.2007CB411502)German Science Foundation(Research Unit 536)Independent Research Project from State Key Laboratory of Cryospheric Science(No.SKLCS-ZZ-2010-02)
文摘Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal varia-tions of δD and δ^18O in precipitation was conducted in 2007-2008 in the Xilin River Basin, Inner Mongolia in the northern China. The 6D and δ^18O values for 54 precipitation samples range from ＋1.1%o to -34.7%0 and -3.0%0 to -269%0, respectively. This wide range indicates that stable isotopes in precipitation are primarily controlled by differ-ent condensation mechanisms as a function of air temperature and varying sources of vapor. The relationship between δD and δ^18O defined a well constrained line given by δD = 7.896180 ＋ 9.5, which is nearly identical to the Meteoric Water Line in the northern China. The temperature effect is clearly displayed in this area. The results of backward tra-jectory of each precipitation day show that the vapor of the precipitation in cold season （October to March） mainly originates from the west while the moisture source is more complicated in warm season （April to September）. A light precipitation amount effect existes at the precipitation event scale in this area. The vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation with lower d-excesses from a monsoon source from the southeastern China.
基金the National Natural Science Foundation of China(41971130)。
文摘Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol steppe is an important native grassland resource in Inner Mongolia Autonomous Region,China.This study aimed to elucidate the dynamics of the forage-livestock balance in the Xilin Gol steppe during the period 2000–2015.We evaluated the forage production and corresponding livestock carrying capacity(LCC)in the growing seasons of 2000–2015 using remote sensing data and field surveys.The spatiotemporal patterns of the forage-livestock balance were then assessed at regional,city(including city,county and banner),and village scales using statistical and household survey data.The results showed that both forage production and LCC decreased in the Xilin Gol steppe from east to west.During the period 2000–2015,the regional average forage production and corresponding LCC fluctuated without following a distinct trend,but were consistent with the variations in precipitation.The forage-livestock balance varied with time,space,and scale.At the regional scale,steppes were overgrazed in the early 2000s,but a forage-livestock balance or even grazing potential was achieved in other years.At the city scale,approximately half of the region exhibited a"forage-livestock balance"since 2000.However,about half of the region still experienced overgrazing,which mainly located in the southwest sandy zones.Such changes may have been affected by the variations in grassland quality,forage production,compensation payment,and so on.We suggest a location-specific management scheme for grazing constraints,ecological compensation payment,and industry development to aid in harmonizing animal husbandry and environmental restoration,while promoting sustainable development goals by 2030.
基金supported by the National Natural Science Foundation of China(31500384,31971464)the Young Science and Technology Talents Support Program in Inner Mongolia Autonomous Region(NJYT-19-B31)the Liaoning Province Joint Fund Project(2020-MZLH-11)。
文摘Grassland degradation is influenced by climate change and human activities,and has become a major obstacle for the development of arid and semi-arid areas,posing a series of environmental and socio-economic problems.An in-depth understanding of the inner relations among grassland vegetation dynamics,climate change,and human activities is therefore greatly significant for understanding the variation in regional environmental conditions and predicting future developmental trends.Based on MODIS(moderate resolution imaging spectroradiometer)NDVI(normalized difference vegetation index)data from 2000 to 2020,our objective is to investigate the spatiotemporal changes of NDVI in the Xilin Gol grassland,Inner Mongolia Autonomous Region,China.Combined with 12 natural factors and human activity factors in the same period,the dominant driving factors and their interactions were identified by using the geographic detector model,and multiple scenarios were also simulated to forecast the possible paths of future NDVI changes in this area.The results showed that:(1)in the past 21 a,vegetation cover in the Xilin Gol grassland exhibited an overall increasing trend,and the vegetation restoration(84.53%)area surpassed vegetation degradation area(7.43%);(2)precipitation,wind velocity,and livestock number were the dominant factors affecting NDVI(the explanatory power of these factors exceeded 0.4).The interaction between average annual wind velocity and average annual precipitation,and between average annual precipitation and livestock number greatly affected NDVI changes(the explanatory power of these factors exceeded 0.7).Moreover,the impact of climate change on NDVI was more significant than human activities;and(3)scenario analysis indicated that NDVI in the Xinlin Gol grassland increased under the scenarios of reduced wind velocity,increased precipitation,and ecological protection.In contrast,vegetation coverage restoration in this area was significantly reduced under the scenarios of unfavorable climate conditions and excessive human activities.This study provides a scientific basis for future vegetation restoration and management,ecological environmental construction,and sustainable natural resource utilization in this area.
基金Knowledge Innovation Project of CAS No.KZCX02-308+1 种基金 The NASA Land Use and Land Cover Change Program No.NAG5-11160
文摘This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, September 27, 1997 and May 23, 2000, respectively. Primarily, 17 sub-class land cover types were recognized, including nine grassland types at community level: F.sibiricum steppe, S.baicalensis steppe, A.chinensis+ forbs steppe, A.chinensis+ bunchgrass steppe, A.chinensis+ Ar.frigida steppe, S.grandis+ A.chinensis steppe, S.grandis+ bunchgrass steppe, S.krylavii steppe, Ar.frigida steppe and eight non-grassland types: active cropland, harvested cropland, urban area, wetland, desertified land, saline and alkaline land, cloud, water body + cloud shadow. To eliminate the classification error existing among different sub-types of the same gross type, the 17 sub-class land cover types were grouped into five gross types: meadow grassland, temperate grassland, desert grassland, cropland and non-grassland. The overall classification accuracy of the five land cover types was 81.0% for 1987, 81.7% for 1991, 80.1% for 1997 and 78.2% for 2000.
基金supported by the National Natural Science Foundation of China(Grant nos.41572043 and 41972053)the National Basic Research Program of China(Grant No.2017YFC0601304)。
文摘The Xilin Group, composed of the Chenming, Laodaomiaogou, Qianshan and Wuxingzhen formations, is one of the Early Paleozoic terranes in the eastern Songliao Massif, mainly consisting of thick layers of fine clastic and carbonate rocks. This study presents LA-ICP-MS zircon U-Pb geochronological data for the Laodaomiaogou and Qianshan formations, further constraining their provenance and the Early Paleozoic tectonic evolution of the Songliao Massif on the eastern Central Asian Orogenic Belt. Most zircons from the Laodaomiaogou and Qianshan formations show magmatic oscillatory zoning and high Th/U ratios(0.26–2.41). Zircon U-Pb dating results indicate that the detrital zircons from the silty mudstone of the Laodaomiaogou Formation yield peak ages of 634 Ma, 775 Ma, 820 Ma, 880 Ma and 927 Ma, as well as multi-episodic Archean to Paleoproterozoic and Mesoproterozoic ages(1405–643 Ma), implying its deposition time is younger than ~634 Ma. Furthermore, the occurrence of Early Cambrian fossils indicates that the Laodaomiaogou Formation was deposited during the late stage of the Early Cambrian(~514 Ma). The zircons from the K-bentonite of the Qianshan Formation show four peak ages of 444 Ma, 471 Ma, 489 Ma and 518 Ma and the youngest age peak of 444 ± 4 Ma(n = 6) indicates that the Qianshan Formation was deposited during the Late Ordovician. In addition, the peak ages of the detrital zircons in the silty mudstone of the Qianshan Formation are 472 Ma and 498 Ma, as well as two other concordant points with;Pb/;Pb apparent ages of 1824 Ma and 1985 Ma. The dating results in this study, together with published data, indicate the absence of Pan-African magmatic events in the Songliao Massif prior to the initial deposition of the Xilin Group, in contrast to those distributed widely in the Jiamusi Massif. Taken together, we conclude that the depositional provenance of the Laodaomiaogou and Qianshan formations was derived from the Songliao Massif. Furthermore, the characteristics of the detrital zircon age composition and rock associations indicate that the Laodaomiaogou Formation formed in a passive continental margin environment, in contrast to the Qianshan Formation, which formed in an active continental margin environment. The above results also imply that the Songliao and Jiamusi massifs might not have collided before the Late Ordovician.
基金The National Natural Science Foundation of China(41671517)The National Key Research and Development Program of China(2016YFC0503700)The Strategic Priority Program of Chinese Academy of Sciences(XDA20010202)
文摘Food safety is an important issue for the development of the national economy and society.Studying regional food supply and demand from the perspective of land resource carrying capacity can provide new references for regional resource sustainability.This study uses the data from farmer and herdsmen household questionnaires,statistical data,land use data,and other sources to construct a land resource carrying capacity(LCC)assessment framework,targeting the food supply and demand of residents in representative areas,specifically the typical grassland pastoral areas,sandy pastoral areas and agro-pastoral areas on the Xilin Gol grassland transects.The three food nutritional indicators of calories,protein and fat were selected for analyzing the balance of land resource carrying capacity.We found that:1)Along the Xilin Gol grassland,the main local food supply showed a shift from meat and milk to grains,vegetables and fruits.2)From north to south along the grassland transects,the calorie intake increased gradually,while the intake of protein and fat was highest in pastoral areas and lowest in agricultural areas.3)The overall land resource carrying capacity of the Xilin Gol grassland transects was in a surplus state,but the land carrying capacity of typical grassland pastoral area was higher than the two other types of areas.This study provides an empirical reference for the sustainable development of regional food nutrition.
文摘The cognition of borderland landscape constitutes an important aspect of understanding the overall geographical order and its internal structure,and is also one of the important contents of the intellectual history of frontier thought.It can facilitate us to think about the geographical spatial correlation of the relations between Chinese borderland regions,and further form a comprehensive control of the spatiotemporal structure of a certain borderland region.As an important ecological transition zone in China,the Xilin Gol region of Inner Mongolia is surrounded by unique cultural-geographical landscapes,such as the source of the Luanhe River,Yuan Dadu ruins,Duolun Huizong Temple and etc.It constitutes an important entry point for us to understand the unique landscape across the trans-Great Wall zone,and thus to understand the spatiotemporal correlation of the Yuan-Ming-Qing dynasties,the Tianxia space as a whole and its contemporary symbolic significance.This paper will conduct a specific discussion and interpretation focusing on this main issue,so as to propose corresponding broader perspectives addressing the issue.
文摘A new rock type of granite, approximate 45 km2 in area and located about 10 km south of Xilinhot, Inner Mongolia, was found in the Sunitezuoqi (or called Su-zuoqi)-Xilinhot tectonic belt and identified as an A-type mia- rolitic intrusion. The pluton has miarolitic structure and is composed chiefly of perthite, quartz, euhedral albite and potassium feldspar. Various types of textures occur in the pluton, such as perthitie, graphic and myrmekite textures. Only quartz is found in miarolitic cavity. This A-type granite with seagull-shaped REE patterns and obvious negative Eu anomaly (d Eu = 0.24—0.28) is high in SiO2 (76%—77%), K and Na (Na2O + K2O = 7.75%—8.15%) and low in Ca (CaO = 0.20%—0.22%), Fe and Mg. Both petrographical observa-tions and chemical compositions indicate that it is an A-type granite. Zircon SHRIMP U-Pb analyses indicate that this A-type granite was emplaced at 276 2 Ma and coeval with the same type of granites in the adjacent areas. Therefore, it suggests that this pluton was likely formed in a post-orogenic extensional setting and probably related to break-off of sub-ducted slabs in Central Asian Orogenic Belt (CAOB), which indicate that the Sunitezuoqi-Xilinhot belt was tectonically evolved into post-orogenic stage since early Permian.
基金supported by the National Natural Science Foundation of China(Grant No.40234045)the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KZCX 2-104).
文摘The Xilin Gol Complex, consisting of deformed and metamorphosed rocks, was exposed as a large geological unit within the Central Asian Orogenic Belt, but its forming and subsequent deformed and metamorphic time has been an issue of little consensus. Petrographic analyses and SHRIMP dating on biotite-plagioclase gneiss, one of the ma-jor rocks within the Xilin Gol Complex, in southeast Xilinhot City, Inner Mongolia, China, where the Xilin Gol Complex was identified and named, yield its lower limit age of 437 3 Ma (2s ) by its magmatic zircon SHRIMP U-Pb dating, and an upper limit age of 316 3Ma (2s ), which was constrained by SHRIMP dating of magmatic zircons from adjacent un-deformed garnet-bearing granite which intruded the Com-plex. The Complex was thus determined to be formed and subsequently deformed/metamorphosed from the late Ordovi-cian-early Silurian to the mid-Carboniferous. Consequently, it is not the Precambrian terrane as previously considered by most geologists. More or less, the major rock——biotite- plagioclase gneiss within the Complex is more likely to be Paleozoic fore-arc turbidite formation before metamorphism and intensive deformation, in which the detrital zircons gave sporadic Precambrian ages as old as up to 3.1 Ga. The source of the turbidite formation is multiple, which may be derived either from the North China Craton, or from the South- Mongolia Micro-continent, or probably came from a poten-tial and undiscovered in situ terranes aged 600—800 Ma or even up to ca 3.1 Ga near the Complex.
文摘CO_(2)减排是当今全球共同关注的热点问题,自然生态系统碳汇的自愿减排(增汇)市场及其运营模式具有非常广阔的发展前景。草地作为重要的自然碳汇之一,受到广泛重视。以锡林郭勒盟为研究区,利用Google Earth Engine平台获取MODIS数据、气象再分析数据与植被覆盖数据,基于CASA模型获取了锡林郭勒盟2001—2024年的植被净初级生产力(NPP)时空动态分布,并综合运用土地利用动态度、偏相关性和贡献指数探究土地覆盖以及气候变化对植被NPP的影响,为该地区实现碳达峰、碳中和目标提供参考。结果表明:(1)2001—2024年锡林郭勒盟植被NPP呈波动上升趋势,多年平均值为302.86 g C·m^(-2)·a^(-1),年均NPP呈现由东北部向西南部递减趋势。(2)锡林郭勒盟的植被NPP主要受土地利用变化和气候变化驱动,受地理因素驱动较小,其中降水对NPP的贡献率达到0.84。(3)随着年份的增长,气候变化对植被NPP的影响逐渐强于土地利用变化,尤其对草甸草原、典型草原、荒漠草原的贡献率分别达到96.01%、63.97%、93.05%。
