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Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example 被引量:1
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作者 Xiao-Dong Guo Qiang Liu +3 位作者 Hui-Rong Zhang Xu-Fei Shi Chuan-Yu Qin Zhi-Qiang Zhang 《China Geology》 CAS CSCD 2024年第1期116-124,共9页
The continuous enrichment of heavy metals in soils has caused potential harm to groundwater.Quantitative methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous studies.Based on the ... The continuous enrichment of heavy metals in soils has caused potential harm to groundwater.Quantitative methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous studies.Based on the theory of groundwater circulation and solid-liquid equilibrium,a simple and easy-touse flux model of soil heavy metals migrating to groundwater is constructed.Based on groundwater environmental capacity,an innovative method for evaluating the harm of heavy metals in soil to groundwater is proposed,which has been applied in Hunchun Basin,Jilin Province,China.The results show that the fluxes of soil heavy metals into groundwater in the study area are Zn,Cu,As,Pb,Cd,Ni,and Hg in descending order.The content of heavy metals in groundwater(As,Hg,Cu,Pb,Zn,Ni,and Cd)in most areas has not risen to the threshold of environmental capacity within 10 years.The harm levels of soil heavy metals to groundwater in the most townships soils are at the moderate level or below.This evaluation method can quantify the flux of soil heavy metals into groundwater simply and quickly,determine the residual capacity of groundwater to heavy metals,evaluate the harm level of soil heavy metals to groundwater,provide support for relevant departments to carry out environmental protection of soil and groundwater,and provide a reference to carry out similar studies for related scholars. 展开更多
关键词 Soil heavy metals As+Hg+Cu+Pb+Zn+Ni+Cd Environmental capacity GROUNDWATER Hazard degree Migration flux model Agricultural geological survey engineering Hunchun Basin jilin province
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Geochemical Anomalies Identified by Multifractal Modeling: Implications for Mineral Exploration in the Ziyoutun Cu-Au District, Jilin Province, China
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作者 MA Huchao WANG Da +3 位作者 BAI Feng LIU Meng GONG Anzhou HU Haiyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期1111-1124,共14页
The Ziyoutun Cu-Au district is located in the Jizhong–Yanbian Metallogenic Belt and possesses excellent prospects. However, the thick regolith and complex tectonic settings present challenges in terms of detecting an... The Ziyoutun Cu-Au district is located in the Jizhong–Yanbian Metallogenic Belt and possesses excellent prospects. However, the thick regolith and complex tectonic settings present challenges in terms of detecting and decomposition of weak geochemical anomalies. To address this challenge, we initially conducted a comprehensive analysis of 1:10,000-scale soil geochemical data. This analysis included multivariate statistical techniques, such as correlation analysis, R-mode cluster analysis, Q–Q plots and factor analysis. Subsequently, we decomposed the geochemical anomalies, identifying weak anomalies using spectrum-area modeling and local singularity analysis. The results indicate that the assemblage of Au-Cu-Bi-As-Sb represents the mineralization at Ziyoutun. In comparison to conventional methods, spectrumarea modeling and local singularity analysis outperform in terms of identification of anomalies. Ultimately, we considered four specific target areas(AP01, AP02, AP03 and AP04) for future exploration, based on geochemical anomalies and favorable geological factors. Within AP01 and AP02, the geochemical anomalies suggest potential mineralization at depth, whereas in AP03 and AP04 the surface anomalies require additional geological investigation. Consequently, we recommend conducting drilling, following more extensive surface fieldwork, at the first two targets and verifying surface anomalies in the last two targets. We anticipate these findings will significantly enhance future exploration in Ziyoutun. 展开更多
关键词 geochemical anomalies multivariate statistical analysis spectrum-area model local singularity analysis mineral prospecting jilin province
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A New Basal Neoceratopsian Dinosaur from the Middle Cretaceous of Jilin Province,China 被引量:7
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作者 JIN Liyong CHEN Jun +1 位作者 ZAN Shuqin Pascal GODEFROIT 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第2期200-206,共7页
A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province,... A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province, China). Helioceratops differs from other basal neoceratopsians with its deep dentary ramus, its steeply-inclined ventral predentary facet, its heterogeneous dentary crowns, and by the denticles and secondary ridges asymmetrically distributed on either side of the primary ridge on its dentary teeth. Along with Auroraceratops and Yamaceratops, Helioceratops represents one of the most derived non-coronosaurian neoceratopsians. The palaeogeographical distribution of basal neoceratopsians appears limited to northern China and southern Mongolia in the current state of our knowledge. It is therefore probable that this region constituted the birthplace for more advanced, Late Cretaceous Coronosanria. 展开更多
关键词 DINOSAURIA Neoceratopsia Middle Cretaceous Quantou Formation jilin province
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Spatiotemporal Variations and Influencing Factors Analysis of PM_(2.5) Concentrations in Jilin Province,Northeast China 被引量:7
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作者 WEN Xin ZHANG Pingyu LIU Daqian 《Chinese Geographical Science》 SCIE CSCD 2018年第5期810-822,共13页
High PM_(2.5) concentrations and frequent air pollution episodes during late autumn and winter in Jilin Province have attracted attention in recent years. To describe the spatial and temporal variations of PM_(2.5) co... High PM_(2.5) concentrations and frequent air pollution episodes during late autumn and winter in Jilin Province have attracted attention in recent years. To describe the spatial and temporal variations of PM_(2.5) concentrations and identify the decisive influencing factors, a large amount of continuous daily PM_(2.5) concentration data collected from 33 monitoring stations over 2-year period from 2015 to 2016 were analyzed. Meanwhile, the relationships were investigated between PM_(2.5) concentrations and the land cover, socioeconomic and meteorological factors from the macroscopic perspective using multiple linear regressions(MLR) approach. PM_(2.5) concentrations across Jilin Province averaged 49 μg/m^3, nearly 1.5 times of the Chinese annual average standard, and exhibited seasonal patterns with generally higher levels during late autumn and over the long winter than the other seasons. Jilin Province could be divided into three kinds of sub-regions according to 2-year average PM_(2.5) concentration of each city. Most of the spatial variation in PM_(2.5) levels could be explained by forest land area, cultivated land area, urban greening rate, coal consumption and soot emissions of cement manufacturing. In addition, daily PM_(2.5) concentrations had negative correlation with daily precipitation and positive correlation with air pressure for each city, and the spread and dilution effect of wind speed on PM_(2.5) was more obvious at mountainous area in Jilin Province. These results indicated that coal consumption, cement manufacturing and straw burning were the most important emission sources for the high PM_(2.5) levels, while afforestation and urban greening could mitigate particulate air pollution. Meanwhile, the individual meteorological factors such as precipitation, air pressure, wind speed and temperature could influence local PM_(2.5) concentration indirectly. 展开更多
关键词 particulate matter PM2.5 spatial variation temporal variation jilin province
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Zircon U-Pb Age of the Lamenzi Formation Volcanic Rocks in the Liuhe Basin of Southern Jilin Province, China 被引量:3
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作者 LIU Xuesong WANG Chenglong ZHANG Meisheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第3期1283-1284,共2页
Objective A large number of Mesozoic volcano-sedimentary basins is distributed in southern Jilin Province,China,and filled with a great set of coal-bearing strata.According to the petroleum resources evaluation by pre... Objective A large number of Mesozoic volcano-sedimentary basins is distributed in southern Jilin Province,China,and filled with a great set of coal-bearing strata.According to the petroleum resources evaluation by previous researchers,these basins have decent exploration potential(Wang Dandan et al.,2017).The Liuhe Basin is one of the 展开更多
关键词 Zircon U-Pb Age of the Lamenzi Formation Volcanic Rocks the Liuhe Basin of Southern jilin province
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EVALUATION OF ECOLOGICAL SERVICES OF JILIN PROVINCE, NORTHEAST CHINA 被引量:2
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作者 YUShu-xia SHANGJin-cheng GUOHuai-cheng 《Chinese Geographical Science》 SCIE CSCD 2004年第3期215-220,共6页
The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic... The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic solutions for ecological problems. The evaluation is based on the methods proposed by COSTANZA et al., and some modifications about unit value of forest and cropland system were made according to the real characters of ecosystem, climate, natural conditions etc., in Jilin Province. Total value of ecosystem services is about 554.404x10(9) yuan(RMB)/a, which is about 4.9 times of GDP of the corresponding period. The results of this study could be used as a fundamental work for the construction of ecological province, which was carried out from 2001, and could provide ecological information for decision-making. Furthermore, the necessities for the further studies on the evaluation of ecological services and natural capital were discussed. 展开更多
关键词 ecological services economic evaluation sustainable development strategic decision-making jilin province
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Uranium Series Chronology of the Late Pleistocene Basalt from the Longgang Volcanoes, Jilin Province 被引量:1
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作者 YUFusheng HANSong +1 位作者 MAZhibang XIERuijie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第2期211-214,共4页
The Longgang volcanic cluster located in Jilin Province belongs to one of the active volcanic regions in northeast China, and has been active in modern times. In view of the multiple eruptions in history, it is very i... The Longgang volcanic cluster located in Jilin Province belongs to one of the active volcanic regions in northeast China, and has been active in modern times. In view of the multiple eruptions in history, it is very important to determine the age of each eruption for evaluating the volcanic hazards. Two alkaline basalt samples taken from Dayizishan and Diaoshuihu were analyzed with the U-series component dating after magnetic separation. The ages of the two samples are (71±9) ka and (106±13) ka B.P., respectively. These data indicate that there existed intensive eruption activities during the late Pleistocene. 展开更多
关键词 U-series component chronology late Pleistocene volcanic eruption Longgang jilin province
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THE EVALUATION AND ANALYSIS OF THE TOURISM RESOURCES IN JILIN PROVINCE 被引量:2
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作者 YUTao-fang GUChao-lin 《Chinese Geographical Science》 SCIE CSCD 2002年第2期186-192,共7页
This paper comprehensively evaluates and analyzes the tourism resources in Jilin Province, China. And it consists of three parts. The first two parts are on the resources evaluation and analysis. Based on the results ... This paper comprehensively evaluates and analyzes the tourism resources in Jilin Province, China. And it consists of three parts. The first two parts are on the resources evaluation and analysis. Based on the results of evaluation about the structural and spatial distribution of the tourism resources, it is found that, the natural resources play fundamental roles in Jilin, while the human and cultural resources are important complementary parts as well. In the spatial distribution analysis, the resources show the characteristic of "six clusters"and "three belts"spatial relations. Four clusters are centered on the cities, which are Changchun, Jilin, Baicheng, Tonghua and Ji′an; one cluster is around the Changbai Moutains and one cluster nears the frontier at Tumen between China, Russia and P.D. R. Korea. And the three belts are: 1) The west belt. It contains Xianghai and Momoge natural protection region. The evident of this zone is its ecological and ethical tourism resources. 2)The middle belt characterized by urban traveling and recreation, including Jilin and Changchun, together with their nearby Nong′an and Siping. 3) The last belt is also the most important one, which is the east zone. It covers the Changbai Mountains, the golden triangles of Tonghua and the Tumen River. This zone is remarkable for its abundant natural landscapes and unique folk customs. In the last part the concept planning is briefly constructed for the tourism resources in Jilin Province according to the above evaluation and analysis. 展开更多
关键词 tourism resources resources evaluation structural and spatial analysis concept planning jilin province
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The Interaction of Population,Industry and Land in Process of Urbanization in China:A Case Study in Jilin Province 被引量:14
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作者 LIU Yanjun ZHOU Guolei +3 位作者 LIU Degang YU Huisheng ZHU Liyuan ZHANG Jing 《Chinese Geographical Science》 SCIE CSCD 2018年第3期529-542,共14页
Urbanization is a complex process that covers a wide range of topics, of which population, industry and land urbanization are three important aspects. Jilin Province is an important agricultural province in China. The... Urbanization is a complex process that covers a wide range of topics, of which population, industry and land urbanization are three important aspects. Jilin Province is an important agricultural province in China. The contradiction between population, industry and land urbanization is especially prominent here, and its coupling development is of great practical significance. In this paper, the coupling degree of population-industry-land urbanization in Jilin Province in 1990, 2000 and 2010 is measured by coupling mode. The spatial pattern of the coupling degree is analyzed by trend surface analysis and global and local spatial autocorrelation. The influence factors and their spatial differentiation are discussed using multiple linear regression(MLR) model and geographic weighted regression(GWR) model. The results show that: 1) the coupling degree of population-industry-land urbanization in Jilin Province is at a low level. Judging from the change of time scale, the urbanization of most research units is becoming more and more coordinated. From the comparison of spatial scales, there is significant spatial difference in the research units of different administrative levels. 2) Judging from the global change trend, the coupling degree of population-industry-land urbanization in the central region is higher than that in western and eastern regions. The coordination of urbanization in the central region is relatively good, and the distribution of the cold and hot spots is basically the same as that overall. 3) The spatial pattern of the coupling degree is related to the cold and hot spot distribution of the influence coefficient of urban population density and per capita urban construction land. The variation of the coupling degree spatial pattern is synchronous with the spatial change of the urban population density influence coefficient. 4) The degree of agglomeration of the urban population is the main factor promoting the coupling pattern of population-industry-land urbanization in Jilin Province, and the extent of its influence is gradually increasing. In addition, the level of city administrative, the efficiency of urban expansion and the capacity of market consumption also have an important influence on the coupling pattern. 展开更多
关键词 population urbanization industry urbanization land urbanization coupling relationship influence mechanism jilin province
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Spatial Structure of Central Places in Jilin Central Urban Agglomeration, Jilin Province, China 被引量:1
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作者 WANG Shijun WANG Yongchao WANG Dan 《Chinese Geographical Science》 SCIE CSCD 2014年第3期375-383,共9页
Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China a... Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions. 展开更多
关键词 jilin central Urban Agglomeration (JCUA) central place system spatial structure FRACTAL spatial image
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CHARACTERISTICS OF CHANGE IN TEMPERATURE DURING THE PAST 50 YEARS IN JILIN PROVINCE OF CHINA 被引量:1
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作者 ZHAO Xin -yi,WAN Jun,WU Xiu -qin(Department of Urban and Environment al Sciences,Peking University,Beijing 100871,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2002年第4期329-332,共4页
Based on the monthly mean temperatu re,the changing processes and tendencies of temperature during1951-2000in Jilin Province,which i s in Northeast China,are analyzed.A nd the spatial characteristics of th e change ar... Based on the monthly mean temperatu re,the changing processes and tendencies of temperature during1951-2000in Jilin Province,which i s in Northeast China,are analyzed.A nd the spatial characteristics of th e change are submitted.In the past 50years the te mperature of Jilin Province was increasing just like the other areas in th e world.Since 1990,the increasing of temperature has been more obvious th an that in the previous 40a.From the west to the east,the province has larger tem perature rising.According to Principal Component Analysis(PCA)of temperature field,Jilin Province is divided int o 3regions and the degree of becoming warmer is different from region to re gion.During the period of 1951to 2000,the annual temperature in Jilin Province has been rising,so has the temperature in winter and summer.The average temperature in t he 1990s was 0.5-2.0℃higher than that in the 1950s.From the west to the east,the increasing of temperature becam e smaller. 展开更多
关键词 temperature change spatial characteristics jilin province
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Spatial Distribution of Different Types of Villages for Rural Revitalization Strategy and Their Influencing Factors:A Case of Jilin Province,China 被引量:1
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作者 YANG Zhipeng WANG Shijun +3 位作者 HAO Feilong MA Li CHANG Xiaodong LONG Wang 《Chinese Geographical Science》 SCIE CSCD 2023年第5期880-897,共18页
Village classification is the first step to implementing China’s rural revitalization(RR)strategy,and understanding the geographic differences in the distribution of village types helps to grasp the pathway of their ... Village classification is the first step to implementing China’s rural revitalization(RR)strategy,and understanding the geographic differences in the distribution of village types helps to grasp the pathway of their unique development.This study spatialized9250 villages in Jilin Province(divided into six types)of China,and their distribution characteristics and influencing factors were examined using methods such as kernel density estimation,Ripley’s K function,the co-location quotient,and Geodetector.The results indicate that the spatial distribution balance and density of village types are different.All types of villages show an agglomeration distribution pattern,but the scale and intensity vary.There is a strong spatial association between agglomerative promotion(AP)and stable improvement(SIm)villages,as well as between characteristic protection(CP)and prospering frontier and enriching people(PE)villages.The factors affecting their distribution include terrain undulation,the percentage of arable land,the distance to the county town,road network density,population density,gross domestic product(GDP),and industrial enterprise density.The influencing factors for the distribution of village types are closely related to the function of each village.Based on the differences in the spatial distribution and influencing factors of different village types,policy suggestions are given for classified development. 展开更多
关键词 village classification spatial differentiation Geodetector rural development jilin province China
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REE geochemistry of the Zhoutan Group metasedimentary rocks in central Jiangxi Province,Southeast China 被引量:3
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作者 HU Gongren LIU Congqiang YU Ruilian 《Chinese Journal Of Geochemistry》 EI CAS 2009年第2期154-162,共9页
Detailed REE and trace elements geochemical studies of the Zhoutan Group metasedimentary rocks in central Jiangxi Province, China, and rock-forming minerals such as garnet were conducted and the results showed that th... Detailed REE and trace elements geochemical studies of the Zhoutan Group metasedimentary rocks in central Jiangxi Province, China, and rock-forming minerals such as garnet were conducted and the results showed that the REEs are partly present in the rock-forming minerals and are dominantly contained in the lattice of accessory minerals. In the process of metamorphism the REEs between garnet porphyroblast and rock and the partitioning of REEs between garnet and the host rock is obviously controlled by the chemical composition of the system. The REEs compositions of metamorphic veins and their minerals display remarked lanthanide tetrad effects and the element pairs Zr-Hf, Y-Ho, Pb-Nd and U-Th have also experienced a certain degree of fractionation with respect to the metasedimentary rocks and they can be used as discriminating indicators to some extent for the occurrence of fluid processes in the process of metamorphism of the Zhoutan Group. 展开更多
关键词 稀土元素地球化学 变质岩石 周潭群 江西省 中国 东南亚 稀土石榴石 副矿物
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Nonparametric multivariate analysis of variance for affecting factors on the extent of forest fire damage in Jilin Province, China
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作者 Jing Li Yanlong Shan +3 位作者 Sainan Yin Mingxia Wang Long Sun Daning Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2185-2197,共13页
Forest fires are influenced by several factors,including forest location,species type,age and density,date of fire occurrence,temperatures,and wind speeds,among others.This study investigates the quantitative effects ... Forest fires are influenced by several factors,including forest location,species type,age and density,date of fire occurrence,temperatures,and wind speeds,among others.This study investigates the quantitative effects of these factors on the degree of forest fire disaster using nonparametric statistical methods to provide a theoretical basis and data support for forest fire management.Data on forest fire damage from 1969 to 2013 was analyzed.The results indicate that different forest locations and types,fire occurrence dates,temperatures,and wind speeds were statistically significant.The eastern regions of the study area experienced the highest fire occurrence,accounting for 85.0%of the total number of fires as well as the largest average forested area burned.April,May,and October had more frequent fires than other months,accounting for 78.9%,while September had the most extensive forested area burned(63.08 ha)and burnt area(106.34 ha).Hardwood mixed forest and oak forest had more frequent fires,accounting for 31.9%and 26.0%,respectively.Hardwood-conifer mixed forest had the most forested area burned(50.18 ha)and burnt area(65.09 ha).Temperatures,wind speeds,and their interaction had significant impacts on forested area burned and area burnt. 展开更多
关键词 jilin province Brown–Forsythe METHOD Scheirer-Ray-Hare METHOD Impact factors FOREST fire damage
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Community Composition and Structure of Soil Macro-Arthropods Under Agricultural Land Uses in the Black Soil Region of Jilin Province, China
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作者 WU Dong-hui ZHANG Bai CHEN Peng 《Agricultural Sciences in China》 CAS CSCD 2006年第6期451-455,共5页
Soil macro-arthropods in the black soil region in Jilin Province of China were investigated with the emphasis laid on the species richness and abundance in relation to the types of land-use, i.e., farm yard, farm land... Soil macro-arthropods in the black soil region in Jilin Province of China were investigated with the emphasis laid on the species richness and abundance in relation to the types of land-use, i.e., farm yard, farm land and Three-North Forest Shelter Belt. Soil macro-arthropods were hand-sorted in the field. A total of 2 357 soil macro-arthropod individuals was captured and fell into 70 families. The results suggested that type of land use affected the species richness and abundance of soil macro-arthropods. Agricultural practices had a strong impact on the soil macro-arthropods community, the conventional cultivations changed the vertical structure of macro-arthropods in the soil profile, and improved the richness and abundance of macro-arthropods in the lower soil layers especially in July. The results also showed that different groups of soil macro-arthropods had various responses to land use changes. 展开更多
关键词 soil macro-arthropods black soil land use jilin province
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Evaluation of Farmers' Working Quality in Jilin Province on the Basis of AHP
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作者 YANG Guang 《Asian Agricultural Research》 2011年第6期75-79,共5页
In terms of the working quality of agricultural production and the working quality of non-agricultural production, the evaluation index system of the working quality of farmers is established. By using integrated fuzz... In terms of the working quality of agricultural production and the working quality of non-agricultural production, the evaluation index system of the working quality of farmers is established. By using integrated fuzzy method based on AHP, we determine the weight of each index, and establish membership matrix of this evaluation index system. Taking Jilin Province as an example, we select developed regions, underdeveloped regions and comparatively developed regions respectively to conduct survey. By using the data from survey, according to the established evaluation index system, we conduct empirical analysis of the working quality of farmers. The results show that the working quality of farmers in the developed regions is relatively high, the working quality of farmers in the comparatively developed regions is ordinary, and the working quality of farmers in the underdeveloped regions is relatively low; the physical quality, educational quality and technological quality of farmers in the developed regions are high; the operation quality of agricultural production of farmers in the underdeveloped regions is high; the operation quality of non-agricultural production of farmers in the comparatively developed regions is high; the working quality of agricultural production of farmers in the comparatively developed regions and underdeveloped regions is higher than the working quality of non-agricultural production of farmers in the comparatively developed regions and underdeveloped regions; the working quality of non-agricultural industries of farmers in the developed regions is higher than the working quality of agricultural production. The urgent priority of constructing new village is to coordinate urban-rural development, and to offer preferential policies and capital for the villages with backward economic development level. 展开更多
关键词 the working quality of farmers Evaluation index system AHP jilin province China
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U-Pb dating and geochemistry of granite porphyry dykes in the Xicha gold-(silver)deposit,southern Jilin Province,China,and their metallogenic significance
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作者 Jian Wang Fengyue Sun +1 位作者 Bile Li Lihui Tian 《Acta Geochimica》 EI CAS CSCD 2020年第4期574-586,共13页
We report U-Pb dating of zircon,as well as geochemical and Hf isotope data,in order to constrain the formation time,magma source,and tectonic setting of granite porphyry dykes in the Xicha gold-(silver)district in sou... We report U-Pb dating of zircon,as well as geochemical and Hf isotope data,in order to constrain the formation time,magma source,and tectonic setting of granite porphyry dykes in the Xicha gold-(silver)district in southern Jilin Province,Northeast China.The zircon grains are euhedral-subhedral,display oscillatory growth zoning and have Th/U ratios varying between 0.11 and 0.78,which together imply a magmatic origin.The dating results indicate the porphyry formed in the Early Cretaceous(122±1 Ma)and it contains SiO2=70.64-72.31 wt%,Al2O3-=13.99-14.64 wt%,K2O+Na2O=6.96-7.81 wt%K2O/Na2O=1.24-2.10,and A/CNK=1.11-1.41.Chemically,the porphyry belongs to a high-K calc-alkaline S-type granite.Chondrite-normalized rare earth elements(REE)patterns show LREE enrichment,light rare earth elements(LREE)/heavy rare earth elements(HREE)=9.93-11.97(La/Yb)N=11.08-15.16,and d Eu=0.69-0.95.On the trace element spider diagram,large ion lithophile elements such as Rb,Ba,K,Th,and U are enriched,whereas the high field strength elements Ti and P are depleted.The e Hf(t)values of zircon from the granite porphyry vary between-17.1 and-13.2,and their Hf two-stage model ages vary from 2.01 to 2.26 Ga,implying that the magma was derived from partial melting of old lower crust.The granite porphyry dykes and many A-type granites in the region formed at the same time,suggesting an extensiona environment.The combination of the occurrence of strong magmatism,large-scale mineralization,and extensiona tectonics throughout much of Eastern China indicate that the Early Cretaceous was a period of significant lithospheric thinning.The southern Jilin Province,therefore,experienced lithospheric thinning during the Early Cretaceous. 展开更多
关键词 Southern jilin province Syn-mineralization dykes Jinchanggou Zircon U-Pb geochronology GEOCHEMISTRY Hf isotopes
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Mesorif Gabbros(External Rif, North Morocco): Ophiolitic Suture Witness or a “Newly Discovered” Manifestation of the Central Atlantic Magmatic Province?
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作者 Faouziya HAISSEN Oriol GIMENO-Vives +4 位作者 Geoffroy MOHN Valérie BOSSE Mohamed Najib ZAGHLOUL Achraf ATOUABAT Dominique FRIZON DE LAMOTTE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第S01期11-12,共2页
The Rif Mountain located in Northern Morocco represents the westernmost extremity of the Peri-Mediterranean Alpine orogenic system.This belt is classically subdivided into:1)Internal zones(or Internal Rif which is an ... The Rif Mountain located in Northern Morocco represents the westernmost extremity of the Peri-Mediterranean Alpine orogenic system.This belt is classically subdivided into:1)Internal zones(or Internal Rif which is an allochthonous metamorphic domain known worldwide thanks to the presence of large peridotite outcrops);2)flysch zones(sediments corresponding to the original cover of the Maghrebian Tethys);and 3)External zones(or External Rif representing the North African margin remnants).The External Rif is itself subdivided into Prerif,Mesorif and Intrarif domains from the South to the North and is composed by Upper Triassic to Cenozoic sediments structured in a nappe stack.Mafic rock intrusions were reported in this External Rif since the preliminary geological studies even if they were wrongly mapped as"granites".Later careful fieldwork and mapping studies specified nevertheless their gabbroic nature.A more recent petrological and geochemical study of a few outcrops of those gabbroic intrusions conducted the corresponding authors,encouraged by the presence of ultramafic rocks(Beni Malek serpentines)in the eastern part of the External Rif to consider those gabbros as oceanic and so,associated to"an ophiolitic suture".Nevertheless,a recent and extended survey on the architecture and the rifting history of the Mesozoic margin of the Maghrebian Tethys focusing mainly on the Mesorif domain favor another interpretation.The detailed petrography of those mafic intrusions(mainly gabbros+dolerites and rarely extrusive rocks);their geochemical fingerprints and mainly their geochronological data(ages around 200 Ma based on U-Pb zircon LA-ICP dating)all together indicate clearly that those mafic intrusions are rather a"newly discovered"manifestation of the Central Atlantic Magmatic Province activity"CAMP"in the External Rif belt.The CAMP magmatism has been largely well described and characterized in all the other geological domains of Morocco(Anti-Atlas,High Atlas,Middle Atlas and Meseta)but never described until the date in the Rif belt which highlights the importance of the results reported here. 展开更多
关键词 external Rif Mesorif GABBRO ophiolitic suture CAMP(the central Atlantic Magmatic province)
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Environmental Implication of Subaqueous Lava Flows from A Continental Large Igneous Province: Examples from the Moroccan Central Atlantic Magmatic Province(CAMP)
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作者 S.EL GHILANI N.YOUBI +4 位作者 J.MADEIRA E.H.CHELLAI ALBERTO LóPEZGALINDO L.MARTINS J.MATA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期117-,共1页
The Early Jurassic volcanic sequence of the Central Atlantic Magmatic Province(CAMP)of Morocco is classically subdivided into four stratigraphic units:the Lower,Middle,Upper and Recurrent Formations separated
关键词 Examples from the Moroccan central Atlantic Magmatic province Environmental Implication of Subaqueous Lava Flows from A Continental Large Igneous province CAMP
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THE MECHANICAL RELATIONSHIP TO THE FORMATION AND DISTRIBUTION OF THEBURIED HILLS AND THE DEEP-SEATED FRACTURAL ZONE IN THE DIWA-TYPE FAULTED BASIN IN CENTRAL HEBEI PROVINCE,CHINA
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作者 LIN Ge & WEI Zhouling (Chang sha Institute of Geotectonics, Acad emia Sinica, Chang sha, 410013) 《Geotectonica et Metallogenia》 1994年第Z1期27-31,共5页
The author proves the existence and movement of a deep-seated fraetural Zone located in the eenter zone of the diwa-type faulted basin in central Hebei Province. This deep-seated fraeturai zone tending in NNE directio... The author proves the existence and movement of a deep-seated fraetural Zone located in the eenter zone of the diwa-type faulted basin in central Hebei Province. This deep-seated fraeturai zone tending in NNE direction is a structural effect of the mtodle East Asin Grustobody in the Mexozoic-Cenozoic. This paper will diseuss the formation, evolution and the meehanism of the deep-seated fraetural zone, faulted basin and the buried hills as well as their relationships. The uthor expounds that the deep geological process is the major factor of the structural effect. 展开更多
关键词 deep-seated fraetural ZONE buried HILL East Asia Crustobody the BASIN in central Hebei province
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