In this paper ecogeographical characteristics of forest soil animal i n mountainous districts of the eastern China was analyzed, and results show that soil fauna was very rich in diversified forest habitat, moreover,...In this paper ecogeographical characteristics of forest soil animal i n mountainous districts of the eastern China was analyzed, and results show that soil fauna was very rich in diversified forest habitat, moreover, as times and spaces varied, their compositions and abundance changed obviously too. Forest so il animal decreased gradually in taxa and individual number from the tropics to cold-temperature zone, and they are higher in zonal forest habitat than in other ones on the same mountain. Forest soil animal also got gradually less with incr easing of depth in soil layer, and distributed principally in surface layer. The activities of human had strong affection on faunal composition and diversity of soil animal. On the tropics and subtropics mountains, forest soil animal are le ss in spring-summer than in autumn-winter, whereas they are more in summer-autum n than in winter-spring from warm-temperate zone to cold-temperate zone.展开更多
A field investigation on Quaternary glacial landforms in Laoshan Motmtain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by t...A field investigation on Quaternary glacial landforms in Laoshan Motmtain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by the meltwater from the overlying ice cap, suggesting that there was at least an ice cap covering Laoshan Mountain and the surrounding areas or even a continental ice sheet over the vast area of Shandong Province in the Late Pleistocene. The ice sheet was obstructed by the Laoshan Mountain, Dazhu Mountain and Xiaozhu Mountain in the coastal areas as it moved toward the Yellow Sea. The ice flows eroded the bedrock and carved the weak intersection of the fault systems in the NE and NW directions into a deep channel, which gradually formed a fjord in the area of the Jiaozhou Bay basin by 20.00 ka BE The seawater gradually invaded the fjord from the beginning of the Holocene （11.00 ka BP） and Jiaozhou Bay was eventually formed. Similar fjords are easily found along the east of China and they share a similar origin because of the Quaternary glaciation in the region.展开更多
As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional li...As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional livelihood approaches. This article applies the theories of livelihood to study the community evolution driven by tourism livelihood and examine three mountainous tourism communities in different stages of tourist area life cycle. Drawing on the methods of GIS spatial analysis, semi-structured interviews and questionnaires, this article proposes a sustainable livelihood framework for ethnic tourism to explore the evolution of ethnic tourism communities by identifying changes in livelihood assets(natural, financial, social, cultural and human capitals) in the process of tourism development. The results show that the development of ethnic tourism has led to changes in the increase of building land, and the diversification of land use functions with a trend of shifting from meeting local villagers' living needs to satisfying tourists, income composition and uneven distribution of tourism income spatially. Ethnic tourism also led to the deterioration of traditional social management structure, collapse of neighboring relationship, the over- commercialization and staged authenticity of ethnic culture, as well as the gradual vanish of agricultural knowledge with a trend of increasing modern business knowledge and higher education. In addition, these changes, involving livelihood assets from natural, economic, human, social and cultural aspects are interrelated and interactive, which form new evolution characters of ethnic community. This study reveals the conflicts over livelihood approaches which have formed new vulnerabilities to impact on sustainable evolution of ethnic communities. This research provides implications for achieving the sustainable development of ethnic communities with the driving force of tourism livelihood.展开更多
Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods use...Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.展开更多
The focal mechanisms of 62 moderate-small earthquakes since 1980 in the ＂ Huoshan seismic window＂ region are calculated with the method developed recently by Snoke, combining the use of the first motion of P, SV and...The focal mechanisms of 62 moderate-small earthquakes since 1980 in the ＂ Huoshan seismic window＂ region are calculated with the method developed recently by Snoke, combining the use of the first motion of P, SV and SH waves with their amplitude ratios. Based on these abundant focal mechanisms, the mean tectonic stress field in the ＂Huoshan seismic window＂ region is inverted with the average stress tensor method, and the result shows that the ＂Huoshan seismic window＂ region is horizontally compressed in the near EW direction and horizontally dilated in the near NS direction, which is in accord with statistical results of focal mechanism parameters. We estimate the difference （also referred to as consistency parameter 0） between the force axis direction of the focal mechanism solution and the mean stress tensor, then further analyze the variation characteristics of 0 versus time, and the relationship with moderately strong earthquakes in the east China region. The result indicates that 0 in the ＂ Huoshan seismic window＂ region is in good correspondence with moderately strong earthquakes in the East China region. When 0 is lower than the mean value, corresponding moderately strong earthquakes may occur in the East China region.展开更多
The Tanlu （Tancheng-Lujiang） fault is one of the major structures in eastern China, which cuts across different blocks and controls the tectonic activity. Using the seismic data from the China Earthquake Networks Ce...The Tanlu （Tancheng-Lujiang） fault is one of the major structures in eastern China, which cuts across different blocks and controls the tectonic activity. Using the seismic data from the China Earthquake Networks Center, we investigate the spatial variations of the b-value in the Dabie-Sulu （Jiangsu-Shandong） organic belt by calculating the b-value of each grid （1~ xl~） from 1970 to 2010. The study shows that： the b-value is smaller in the Tanlu fault and its adjacent area, which might suggest that the major earthquake recurrence period is relatively long due to the lower frequency of small earthquake activity. In both sides of Tanlu fault, the b-value is higher at the edge of Sulu block and the eastern part of Dabie orogenic belt. The b values are higher in North China central orogenic belt, and small earthquake activity which occurred along the central orogenic belt is frequent. Additionally, combined with geological and geophysical study, we find that the b-value has a certain correspondence relationship with the lithologic distribution, which informs us that seismic activity features are closely related to the inhomogeneous media in the crust.展开更多
The Ning-Wu(Nanjing-Wuhu) Basin is one of the most important volcanic basins in the Middle-Lower Yangtze River Valley,eastern China.It consists of four volcanic units,i.e.,the Longwangshan,Dawangshan,Gushan,and Niangn...The Ning-Wu(Nanjing-Wuhu) Basin is one of the most important volcanic basins in the Middle-Lower Yangtze River Valley,eastern China.It consists of four volcanic units,i.e.,the Longwangshan,Dawangshan,Gushan,and Niangniangshan Formations.Their LA-ICP MS U-Pb zircon ages are 134.8±1.8,132.2±1.6,129.5±0.8,and 126.8±0.6 Ma,respectively.Results of this study indicate that all volcanic rocks in the Ning-Wu Basin were formed in the Early Cretaceous from 135 to 127 Ma,lasting 8-10 m.y.No Jurassic volcanic activities occurred in any of the volcanic basins of the Middle-Lower Yangtze River Valley,including the Ning-Wu Basin.These new chronological results provide significant evidence for further study of this region to improve our understanding of Mesozoic tectonic,magmatic,and metallogenic processes of eastern China.展开更多
Geomagnetic polarity transitions were the most important phenomena in the study of the geomagnetic field evolution and the earth＇s deep interior dynamics. The Miocene postcollisional ultrapotassic-potassic rocks are ...Geomagnetic polarity transitions were the most important phenomena in the study of the geomagnetic field evolution and the earth＇s deep interior dynamics. The Miocene postcollisional ultrapotassic-potassic rocks are widely distributed in the Lhasa Block of southern Tibet. Paleomagnetic studies on the Wuyu Formation indicated that these volcanic rocks recorded the C5Bn.2n-C5Bn.lr and C5ACr-C5ACn geomagnetic polarity transitions. The virtual geomagnetic poles （VGPs） of these two polarity transitions were located in the Atlantic and the central Pacific, respectively. Due to data scarcity, it remains unclear whether VGP paths of Miocene geomagnetic polarity transitions were longitudinal preference and/or 90° away from the sampiing sites.展开更多
A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case stud...A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case study from the Early Cretaceous Xujiaweizi fault-depression shows that the formation mechanism of in-situ volcanic reservoirs is characterized by"fault-controlled body,body-controlled facies,facies-controlled reservoir,and reservoir-controlled accumulation".In other words,deep faults control the volcanic eruption type,volcanic body,and gas reservoir distribution;the volcanic body determines the spatial distribution of volcanic facies and volcanic gas reservoir size;the volcanic facies control reservoir physical properties and effective thickness of gas formation;the volcanic reservoir properties control gas reservoir type and gas productivity.The result is useful to guiding the discovery of in-situ volcanic gas reservoirs in faulted basins in both theory and practice.展开更多
文摘In this paper ecogeographical characteristics of forest soil animal i n mountainous districts of the eastern China was analyzed, and results show that soil fauna was very rich in diversified forest habitat, moreover, as times and spaces varied, their compositions and abundance changed obviously too. Forest so il animal decreased gradually in taxa and individual number from the tropics to cold-temperature zone, and they are higher in zonal forest habitat than in other ones on the same mountain. Forest soil animal also got gradually less with incr easing of depth in soil layer, and distributed principally in surface layer. The activities of human had strong affection on faunal composition and diversity of soil animal. On the tropics and subtropics mountains, forest soil animal are le ss in spring-summer than in autumn-winter, whereas they are more in summer-autum n than in winter-spring from warm-temperate zone to cold-temperate zone.
基金Doctorate Research Program of China University of Petroleum (No. Y020109)
文摘A field investigation on Quaternary glacial landforms in Laoshan Motmtain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by the meltwater from the overlying ice cap, suggesting that there was at least an ice cap covering Laoshan Mountain and the surrounding areas or even a continental ice sheet over the vast area of Shandong Province in the Late Pleistocene. The ice sheet was obstructed by the Laoshan Mountain, Dazhu Mountain and Xiaozhu Mountain in the coastal areas as it moved toward the Yellow Sea. The ice flows eroded the bedrock and carved the weak intersection of the fault systems in the NE and NW directions into a deep channel, which gradually formed a fjord in the area of the Jiaozhou Bay basin by 20.00 ka BE The seawater gradually invaded the fjord from the beginning of the Holocene （11.00 ka BP） and Jiaozhou Bay was eventually formed. Similar fjords are easily found along the east of China and they share a similar origin because of the Quaternary glaciation in the region.
基金supported by the National Natural Science Foundation of China(Grant No.41361033)
文摘As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional livelihood approaches. This article applies the theories of livelihood to study the community evolution driven by tourism livelihood and examine three mountainous tourism communities in different stages of tourist area life cycle. Drawing on the methods of GIS spatial analysis, semi-structured interviews and questionnaires, this article proposes a sustainable livelihood framework for ethnic tourism to explore the evolution of ethnic tourism communities by identifying changes in livelihood assets(natural, financial, social, cultural and human capitals) in the process of tourism development. The results show that the development of ethnic tourism has led to changes in the increase of building land, and the diversification of land use functions with a trend of shifting from meeting local villagers' living needs to satisfying tourists, income composition and uneven distribution of tourism income spatially. Ethnic tourism also led to the deterioration of traditional social management structure, collapse of neighboring relationship, the over- commercialization and staged authenticity of ethnic culture, as well as the gradual vanish of agricultural knowledge with a trend of increasing modern business knowledge and higher education. In addition, these changes, involving livelihood assets from natural, economic, human, social and cultural aspects are interrelated and interactive, which form new evolution characters of ethnic community. This study reveals the conflicts over livelihood approaches which have formed new vulnerabilities to impact on sustainable evolution of ethnic communities. This research provides implications for achieving the sustainable development of ethnic communities with the driving force of tourism livelihood.
基金supported by a grant from the Major State Basic Research Development Program of China (973 Program) (Grant No. 2015CB452706)National Natural Science Foundation of China (Grant No. 41471469)provided by the national scientific datasharing project Earth System Science Data Sharing Network
文摘Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.
基金funded by the Youth Program of Earthquake Scientific Research Fund of Anhui Province(20120704)Contract Subject of Earthquake Administration of Anhui Province(201210)
文摘The focal mechanisms of 62 moderate-small earthquakes since 1980 in the ＂ Huoshan seismic window＂ region are calculated with the method developed recently by Snoke, combining the use of the first motion of P, SV and SH waves with their amplitude ratios. Based on these abundant focal mechanisms, the mean tectonic stress field in the ＂Huoshan seismic window＂ region is inverted with the average stress tensor method, and the result shows that the ＂Huoshan seismic window＂ region is horizontally compressed in the near EW direction and horizontally dilated in the near NS direction, which is in accord with statistical results of focal mechanism parameters. We estimate the difference （also referred to as consistency parameter 0） between the force axis direction of the focal mechanism solution and the mean stress tensor, then further analyze the variation characteristics of 0 versus time, and the relationship with moderately strong earthquakes in the east China region. The result indicates that 0 in the ＂ Huoshan seismic window＂ region is in good correspondence with moderately strong earthquakes in the East China region. When 0 is lower than the mean value, corresponding moderately strong earthquakes may occur in the East China region.
基金jointly supported by the Fundamental Research Funds for the Central Universities of China(ZY20140202)the Spark Program of Earthquake Science and Technology(XH15040Y)
文摘The Tanlu （Tancheng-Lujiang） fault is one of the major structures in eastern China, which cuts across different blocks and controls the tectonic activity. Using the seismic data from the China Earthquake Networks Center, we investigate the spatial variations of the b-value in the Dabie-Sulu （Jiangsu-Shandong） organic belt by calculating the b-value of each grid （1~ xl~） from 1970 to 2010. The study shows that： the b-value is smaller in the Tanlu fault and its adjacent area, which might suggest that the major earthquake recurrence period is relatively long due to the lower frequency of small earthquake activity. In both sides of Tanlu fault, the b-value is higher at the edge of Sulu block and the eastern part of Dabie orogenic belt. The b values are higher in North China central orogenic belt, and small earthquake activity which occurred along the central orogenic belt is frequent. Additionally, combined with geological and geophysical study, we find that the b-value has a certain correspondence relationship with the lithologic distribution, which informs us that seismic activity features are closely related to the inhomogeneous media in the crust.
基金supported by National Natural Science Foundation of China (Grant Nos. 40830426,40803015)Deep Exploration Technology and Experimentation (Grant No. Sinoprube-03-02-05)+2 种基金Anhui Public Geologic Projects (Grant No. 2007-1)New Century Excellent Talents in University (Grant No. NCET-10-0324)Scientific Research Project of Centre of Excellence in Ore Deposits,University of Tasmania (Grant No. CODES2009 P2.N3)
文摘The Ning-Wu(Nanjing-Wuhu) Basin is one of the most important volcanic basins in the Middle-Lower Yangtze River Valley,eastern China.It consists of four volcanic units,i.e.,the Longwangshan,Dawangshan,Gushan,and Niangniangshan Formations.Their LA-ICP MS U-Pb zircon ages are 134.8±1.8,132.2±1.6,129.5±0.8,and 126.8±0.6 Ma,respectively.Results of this study indicate that all volcanic rocks in the Ning-Wu Basin were formed in the Early Cretaceous from 135 to 127 Ma,lasting 8-10 m.y.No Jurassic volcanic activities occurred in any of the volcanic basins of the Middle-Lower Yangtze River Valley,including the Ning-Wu Basin.These new chronological results provide significant evidence for further study of this region to improve our understanding of Mesozoic tectonic,magmatic,and metallogenic processes of eastern China.
基金supported by China Geological Survey(Grant No.1212010511704)
文摘Geomagnetic polarity transitions were the most important phenomena in the study of the geomagnetic field evolution and the earth＇s deep interior dynamics. The Miocene postcollisional ultrapotassic-potassic rocks are widely distributed in the Lhasa Block of southern Tibet. Paleomagnetic studies on the Wuyu Formation indicated that these volcanic rocks recorded the C5Bn.2n-C5Bn.lr and C5ACr-C5ACn geomagnetic polarity transitions. The virtual geomagnetic poles （VGPs） of these two polarity transitions were located in the Atlantic and the central Pacific, respectively. Due to data scarcity, it remains unclear whether VGP paths of Miocene geomagnetic polarity transitions were longitudinal preference and/or 90° away from the sampiing sites.
基金supported by the National Basic Research Program of China(Grant No.2009CB219308)
文摘A large number of in-situ volcanic reservoirs have been discovered from the Meso-Cenozoic rift basin group in eastern China.Based on drilling results in combination with geological and geophysical analysis,a case study from the Early Cretaceous Xujiaweizi fault-depression shows that the formation mechanism of in-situ volcanic reservoirs is characterized by"fault-controlled body,body-controlled facies,facies-controlled reservoir,and reservoir-controlled accumulation".In other words,deep faults control the volcanic eruption type,volcanic body,and gas reservoir distribution;the volcanic body determines the spatial distribution of volcanic facies and volcanic gas reservoir size;the volcanic facies control reservoir physical properties and effective thickness of gas formation;the volcanic reservoir properties control gas reservoir type and gas productivity.The result is useful to guiding the discovery of in-situ volcanic gas reservoirs in faulted basins in both theory and practice.
