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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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Current Situation and Development Countermeasures on Grassland Resource in Farming-pasturing Ecotone in West Jilin Province 被引量:6
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作者 尚红梅 《Agricultural Science & Technology》 CAS 2010年第7期94-98,共5页
Upon the current degradation situation of grassland in west Jilin Province,I analyzed the effects of natural factors and human activities on the degradation of grassland,and further purposefully put forward countermea... Upon the current degradation situation of grassland in west Jilin Province,I analyzed the effects of natural factors and human activities on the degradation of grassland,and further purposefully put forward countermeasures on the remediation and development of grassland.As a conclusion,scientifically utilizing and protecting the grassland resources could suppress grassland degradation,promoting the sustainable development of regional economy. 展开更多
关键词 west jilin province Farming-pasturing ecotone Grassland Resource Current situation Development Countermeasures
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Ecological Suitability Evaluation on Agricultural Land in Western Jilin Province Based on Fuzzy Mathematics 被引量:2
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作者 臧立娟 王凤艳 任建超 《Agricultural Science & Technology》 CAS 2012年第8期1757-1761,共5页
[Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structura... [Objective] This study was to evaluate the ecological suitability of agricultural land in western Jilin Province, with the aim to provide basis for the effective application of agricultural resources and the structural adjustment of land use. [Method] The evaluation index system was constructed based on fuzzy mathematic method according to the principles of systematic, dominant, effectiveness and feasibility; based on law of tolerance, reasonable evaluation criteria were determined according to the ecological amplitude of crops; based on GIS processing, the initial data completed the mathematical operation by using the VBA program in Excel. [Result] The area of agricultural land grade I was 5 512 km2, grade II of 25 985 km2, grade Ill of 7 907 km2, and area of land not suitable for agriculture was 6 312 km2. According to the evaluation results, the key areas for land use adjustment were Zhenlai County, Da'an County, Tongyu County and western Changling County. The directions of land use adjustment included improving irrigation and drainage conditions, governing land salinization and conversion of cropland to forest and grassland. [Conclusion] This study provided basis for the effective application of agricultural resources and ecological environment construction in western Jilin Province. 展开更多
关键词 Land use Suitability evaluation Agricultural land Fuzzy mathematic method western jilin province
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Study on Extracting Information about Settlements Distribution in Western Jilin Province Based on Decision Tree Model 被引量:1
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作者 连懿 陈圣波 +1 位作者 王亚楠 逄超 《Journal of Landscape Research》 2010年第2期92-95,共4页
With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information... With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information about settlements in western Jilin Province, and the manually-extracted information about settlements in western Jilin Province was evaluated by confusion matrix. The results showed that Decision Tree Model was convenient for extracting settlements information by integrating spectral and texture features, and the accuracy of such a method was higher than that of the traditional Maximum Liklihood Method, in addition, calculation methods of extracting settlements information by this mean were concluded. 展开更多
关键词 SETTLEMENTS TM western jilin province Spectral characteristics Texture features Decision Tree Confusion matrix
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Ecological Footprint and Major Driving Forces in West Jilin Province, Northeast China 被引量:16
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作者 WANG Mingquan LIU Jingshuang +1 位作者 WANG Jinda ZHAO Guangying 《Chinese Geographical Science》 SCIE CSCD 2010年第5期434-441,共8页
The environmental impact caused by local people (ecological footprint of consumption, EFc) and the actual environmental impact that the ecosystem burdens (ecological footprint of production, EFp) in West Jilin Pro... The environmental impact caused by local people (ecological footprint of consumption, EFc) and the actual environmental impact that the ecosystem burdens (ecological footprint of production, EFp) in West Jilin Province, Northeast China from 1986 to 2006 were evaluated by using ecological footprint (EF) method. And the major driving forces of EFc and EFp were analyzed by STIRPAT model. Both EFc and EFp showed increasing trends in 1986-2006, accompanied by decreasing ecological deficits but expanding ecological overshoots. Population (P), GDP per capita (A1), quadratic term of GDP per capita (A2), urbanization (Tα1), and quadratic term of urbanization (Ta2) were important influencing factors of EFc, among which Tα2 and Tα1 were the most dominate driving forces of EFc. A1, A2 and Tα2 were important influencing factors of EFp, among which A2 and A1 were the most dominate driving forces of EFp. In 1986-2006, the classical Environmental Kuznets Curve hypothesis did not exist between A2 and EF (both EFc and EFp), but did between Tα2 and EF. The results indicate that enhancing the urbanization process and diversifying economic sources is one of the most effective ways to reduce the environmental impact of West Jilin Province. Moreover, importance should be attached to improve the eco-efficiency of resource exploitation and consumption. 展开更多
关键词 ecological footprint STIRPAT model ecological deficit ecological overshoot west jilin province
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A STUDY ON DESERTIFICATION OF WEST JILIN PROVINCE BASED ON REMOTE SENSING AND GIS TECHNIQUES 被引量:4
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作者 ZHU Jin hua, LI Jin song(Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P.R. China) 《Chinese Geographical Science》 SCIE CSCD 2002年第1期73-79,共7页
'West Jilin Province' in this paper means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, Songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping andNong' an which have be... 'West Jilin Province' in this paper means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, Songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping andNong' an which have been suffered from desertification. In west Jilin Province there are three sandzones passing through, they are Xiang (Xianghai) -Wu (Ulan Tug) sand zone, Hai-Feng sand zone, andTao'er River right bank sand zone. The desertification area of west Jilin Province is 819 100 ha,making up 12. 5% of the total land area. Among desertification types, in Jilin Province lightdesertification is the major, then is medium decertification, hevey desertification is the least.According to the comparison of the interpretation results of the Landsat images of the 1980s and the1990s by remote sensing and GIS techniques, it can be seen that the desertification area in westJilin Province basically didn't change on the whole, only increased 6130 ha, making up 0. 8% of thedesertification area, change scale is less than 1%. Evidently, desertification is controlled mostly,but some areas are continuing deterioration. The desertification process of China can be dividedinto three types according to origin nature, they are sandy steppe desertification, fixed sandarea(sand land) activation and dunes transfer invasion. Reasons of desertification of West JilinProvince are analyzed, they include natural factors (such as material source factors, chimatefactors) and artificial factors (such as destroying grass to reclaim, steppe decreasing greatly,illegally feeling shelter forest stands, constructing reservoir to influence eco-environment etc. ).Some suggestions are put forward as follows: establishing the social project for ecologicalreconstruction of degenerated land; intensifying planning and management of land use, revertingfarmland into forestland or pasture in a planned way. The key desertification control is to dependmainly on policy and management, then control techniques. 展开更多
关键词 remote sensing (RS) and GIS techniques DESERTIFICATION west jilin province
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Present situation and tendency of saline-alkali soil in west Jilin Province 被引量:9
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作者 LIU Hui-qing, XU Jia-wei, WU Xiu-qin (Institute of Urban and Environment Science, Northeast Normal University, Changchun 130024, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期321-328,共8页
Taking west Jilin Province as an example, this paper put forward the assessment index of salinization, and based on it, the authors present the distribution characteristics of saline-alkali soil in the 1980s and the 1... Taking west Jilin Province as an example, this paper put forward the assessment index of salinization, and based on it, the authors present the distribution characteristics of saline-alkali soil in the 1980s and the 1990s in west Jilin and analyze its physical and chemical properties in detail. The developing tendency of salinization was also inferred by comparing the saline-alkali soil of the 1980s with that of the 1990s. Finally, the natural and human factors leading to salinization are analyzed. 展开更多
关键词 saline-alkali soil west jilin SALINIZATION degraded soil
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DYNAMICS OF SANDY DESERTIFICATION AND ITS DRIVING FORCES IN WESTERN JILIN PROVINCE 被引量:4
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作者 LIFang LIUZhi-ming 《Chinese Geographical Science》 SCIE CSCD 2004年第1期57-62,共6页
By establishing the interpreting elements, and applying supervised classification, the sandy desertific- ation was interpreted and the desertified land areas of the counties in the western Jilin Province in 1986 and i... By establishing the interpreting elements, and applying supervised classification, the sandy desertific- ation was interpreted and the desertified land areas of the counties in the western Jilin Province in 1986 and in 2000 were obtained. Taking Tongyu and Qian’an as examples, the natural driving forces and man-made driving forces were analyzed. The paper comes the conclusions that the material sources and the warming and dry climate are the internal causes of potential land desertification; the irrational human activities, such as destroying forest and reclaiming the grassland, are the external causes of potential land desertification; while more rational human activities, such as planting trees and restoring grassland can reverse the land desertification. Furthermore, the countermeasures and suggestions for the development of agriculture and animal husbandry in the western Jilin Province are put forward. 展开更多
关键词 sandy desertification remote sensing DYNAMICS driving forces western 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
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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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A GIS-based Tupu Analysis of Dynamics of Saline-alkali Land in Western Jilin Province 被引量:1
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作者 REN Chunying ZHANG Bai +3 位作者 WANG Zongming SONG Kaishan LIU Dianwei LIU Zhiming 《Chinese Geographical Science》 SCIE CSCD 2007年第4期333-340,共8页
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the wes... Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980-2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995-2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development. 展开更多
关键词 Tupu saline-alkali land GIS jilin province
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Present Situation of West Wetland in Jilin Province and Countermeasures for Restoration
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作者 Wang Xuege Lv Jun +1 位作者 Wang Yanmei Wei Chunfeng 《Meteorological and Environmental Research》 CAS 2017年第5期54-55,60,共3页
The western region of Jilin Province is rich in wetland resources,and its biodiversity is rich. However in recent years,due to the reduction of natural precipitation,human activities and other causes,wetland shrivels ... The western region of Jilin Province is rich in wetland resources,and its biodiversity is rich. However in recent years,due to the reduction of natural precipitation,human activities and other causes,wetland shrivels and degenerates,biodiversity reduces,and ecosystem security is threatened. In this paper,the rivers and lakes connecting project in western Jilin Province is proposed to restore the damaged wetlands and protect important wetlands. 展开更多
关键词 west of jilin province WETLAND degradation ECOLOGICAL environment
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RESPONSES OF WETLAND ECO SECURITY TO LAND USE CHANGE IN WESTERN JILIN PROVINCE, CHINA
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作者 WANG Zhi-qiang ZHANG Bai +2 位作者 YANG Guang WANG Zong-ming ZHANG Shu-qing 《Chinese Geographical Science》 SCIE CSCD 2005年第4期330-336,共7页
By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes... By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes (LUCC) in the western Jilin Province were studied from 1930 to 2000. The results show that the landscape elements of grassland, wetland, forestland and water area shrank rapidly, and wetlands underwent huge losses in the study period due to the conversion from wetland into arable land and grassland in large quantities. The responses of wetland eco-security to LUCC were inverse evolvement of wetland vegetation, loss of biodiversity, water deficiency in wetland ecosystem, the changes of the heterogeneity of wetlands and the fragmentation of the wetland habitats. Suggestions were given for protection of wetlands and the regional sustainable development. 展开更多
关键词 LUCC wetland eco-security RS GIS western jilin province
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Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example
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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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Characterization of mineral element fingerprints under soilcrop systems in eastern and western rice-producing areas of Jilin Province,China
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作者 BU Yuanbo CAO Shuhe LI Linze 《Global Geology》 2022年第4期277-286,共10页
To assess the indicative function of the fingerprint characteristics of mineral elements for small agricultural producing areas,20 sets of soil surface samples and corresponding rice samples were collected from Songyu... To assess the indicative function of the fingerprint characteristics of mineral elements for small agricultural producing areas,20 sets of soil surface samples and corresponding rice samples were collected from Songyuan and Hunchun of Jilin Province,China.Forty-six mineral elements of brown rice,soil,and rice husk were examined by inductively coupled plasma mass spectrometry.Ten characteristic elements(Li,Ag,Y,Bi,U,Eu,Er,Rb,Mo and As)were identified via multivariate statistics(Variance importance value analysis and rank sum test in SPSS and SIMCA software packages).The correlation of mineral elements in brown rice,soil,and rice husks of the two sample areas was analyzed and regression analysis models of characteristic mineral elements in brown rice were developed.The results indicate that a correlation exists among brown rice,soil,and rice husks in the same area,and the correlation tests using selected elements showed that all correlation coefficients were 0.65 or above.Differences in brown rice were found between different regions.Consequently,brown rice producing areas can be distinguished by the fingerprint characteristics of mineral elements. 展开更多
关键词 jilin province rice producing area soil-crop system mineral element fingerprint
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Comparative Advantage of Maize Production in Jilin Province 被引量:2
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作者 张大瑜 吴景贵 +4 位作者 陈日曌 祝延立 吕铁彪 赵仁贵 刘武仁 《Agricultural Science & Technology》 CAS 2010年第6期53-56,共4页
The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed th... The comparative advantage of maize production in Jilin Province was analyzed based on the sow area index,unit yield index,benefit index and comprehensive comparative advantage index in this study.The results showed that compared with other provinces in China,there was obvious comparative advantage in sow area index and unit yield index of maize in Jilin,the average of which stood for the first and the fourth in China from 2002 to 2006;there was no comparative advantage of benefit index compared with the average value of the whole countries,the average of which stood for the 14th in China from 2002 to 2006;the comprehensive comparative advantage in Jilin provincial maize production showed significant comparative advantage,the average of which stood for the fourth in China from 2002 to 2006.On the basis of the above,the suggestions to develop maize production in Jilin province had been put forward. 展开更多
关键词 Sow area index Unit yield index Benefit index Comprehensive comparative advantage index MAIZE jilin province
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Types and Spatial Distribution of Geo-tourism Resources in Jilin Province of China 被引量:1
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作者 许振北 孟涛 +3 位作者 邢立新 孙浩 毕记省 王东 《Journal of Landscape Research》 2012年第2期58-62,共5页
Natural geological conditions and geo-tourism resources in Jilin Province were introduced,and distribution features of the local major tourist resources(vegetation-covered eastern region,grass swamp on western plain) ... Natural geological conditions and geo-tourism resources in Jilin Province were introduced,and distribution features of the local major tourist resources(vegetation-covered eastern region,grass swamp on western plain) were studied.Jingyu Volcanic Mineral Spring Geo-park,Changbai Mountain Geo-park and Qian'an Mud Forest Geo-park were studied as typical geo-tourism resources,so as to provide basic data for the systematic development and construction of geo-tourism resources in Jilin Province. 展开更多
关键词 Geo-tourism RESOURCES GEOLOGICAL RELICS Classification Spatial distribution jilin province
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Present situation and prospects of forest ecological network in Jilin Province, China 被引量:1
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作者 王宪成 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期323-326,338,共4页
This paper makes a brief introduction of the ecological environment, forestry achievements, and the existing questions of Jilin Province. The task of forest ecological network and eight questions demanding prompt solu... This paper makes a brief introduction of the ecological environment, forestry achievements, and the existing questions of Jilin Province. The task of forest ecological network and eight questions demanding prompt solution were discussed based on the present situation of forestry in Jilin Province. The author also made prospects for future application of bio-technique, infor-mation technology, new material technology and nuisance-free forest health technology in forest ecological network. 展开更多
关键词 Forest Ecology Network construction jilin province Forestry Development Forest management New technology
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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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Cretaceous Volcanic Events in Southeastern Jilin Province,China:Evidence from Single Zircon U-Pb Ages 被引量:8
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作者 CHEN Yuejun SUN Chunlin SUN Yuewu SUN Wei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1194-1200,共7页
Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize ... Mesozoic volcanic rocks in southeastern Jilin Province are an important component of the huge Mesozoic volcanic belt in the northeastern area. Study of the age of their formation is of great significance to recognize Mesozoic volcanic rule in northeastern China. Along with the research of rare Mesozoic biota and extensive Mesozoic mineralization in western Liaoning, a number of researchers have focused on Mesozoic volcanic events. The authors studied the ages of the Cretaceous volcanic rocks in southeastern Jilin Province using single Zircon U-Pb. The result shows that the Sankeyushu Formation volcanic rocks in the Tonghua area are 119.2 Ma in age, the Yingcheng Formation in the Jiutai area 113.4±3.1 Ma, the Jinjiatun Formation in Pinggang Town of Liaoyuan City and the Wufeng volcanic rocks in the Yanji area 103.2±4.7 Ma and 103.6±1 Ma, respectively. Combined with the data of recent publication on volcanic rocks ages; the Cretaceous volcanic events in southeastern Jilin Province can be tentatively subdivided into three eruption periods: 119 Ma, 113 Ma and 103 Ma. The result not only provides important chronology data for subdividing Mesozoic strata in southeastern Jilin Province, establishing Mesozoic volcanic event sequence, discussing geological tectonic background, and surveying the relation between noble metals to the Cretaceous volcanic rocks, but also offers important information of Mesozoic volcanism in northeastern China. 展开更多
关键词 age of zircon U-Pb volcanic event CRETACEOUS jilin province
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Extreme meteorological disaster effects on grain production in Jilin Province, China 被引量:10
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作者 XU Lei ZHANG Qiao +3 位作者 ZHANG Jing ZHAO Liang SUN Wei JIN Yun-xiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期486-496,共11页
Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats... Extreme meteorological disaster effects on grain production is mainly determined by the interaction between danger degree of hazard-induced factors and vulnerability degree of hazard-affected bodies. This paper treats physical exposure, sensitivity of the response to the impact, and capabilities of disaster prevention and mitigation as a complex system for vulnerability degree of hazard-affected bodies, which included the external shocks and internal stability mechanism. Hazard-induced factors generate external shocks on grain production systems though exposure and sensitivity of hazard-affected body, and the result can be represented as affected area of grain. By quantile regression model, this paper depicts the quantitative relationship between hazard-induced factors of extreme meteorological disaster and the affected area in the tail of the distri- bution. Moreover, the model of production function have also been utilized to expound and prove the quantitative relationship between the affected area and final grain output under the internal stability mechanism of the agricultural natural resources endowment, the input factors of agricultural production, and the capacity of defending disaster. The empirical study of this paper finds that impact effects of drought disaster to grain production system presents the basic law of "diminishing marginal loss", namely, with the constant improvement of the grade of drought, marginal affected area produced by hazard-induced factors will be diminishing. Scenario simulation of extreme drought impact shows that by every 1% reduction in summer average rainfall, grain production of Jilin Province will fell 0.2549% and cut production of grain 14.69% eventually. In re- sponse to ensure China's grain security, the construction of the long-term mechanism of agricultural disaster prevention and mitigation, and the innovation of agricultural risk management tools should be also included in the agricultural policy agenda. 展开更多
关键词 extreme meteorological disaster grain production danger degree of hazard-induced factors vulnerability degreeof hazard-affected bodies jilin province in China
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