Geochemical Anomalies Identified by Multifractal Modeling: Implications for Mineral Exploration in the Ziyoutun Cu-Au District, Jilin Province, China

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.

Construction land expansion and influencing factors of typical river valley cities in Northeast China: Taking Jilin City as an example

Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysis of expansion speed and strength,fractal dimension,barycenter coordinate transfer index and sector analysis.The ultimate-goal is to analyze the driving and restrictive factors that affect the spatial expansion of river valley cities.The results indicate that(1)the expansion speed of urban land in Jilin City has been re-latively slow in the past 30 years,while only slightly faster in 2010–2020;(2)in the spatial dimension,Jilin City mainly expanded to the south,then to the west,and extensive expansion has resulted in complex mor-phology with little stability and compactness;(3)the expansion is affected by multiple factors,of which the positive factor is industrial development,while the restrictive factors include natural factors,population loss,etc.This study provides a case for the formulation of land use policies and land space planning in river valley cities.

Withdrawal Intention of Farmers from Vacant Rural Homesteads and Its Influencing Mechanism in Northeast China: A Case Study of Jilin Province

The effective use of land in Northeast China is of great significance for ensuring national food security and regional rural revitalization.In this study,based on the survey data collected from Jilin Province,Northeast China,we analyzed the vacancy rates of rural homesteads in suburban,outer suburban,and remote villages,as well as the withdrawal intention of rural-settled farmers,urbansettled farmers,and farmers with urban and rural dual residency from vacant homesteads.From the perspective of farmers’perceptions,this study constructed a theoretical framework of the influence mechanism of their withdrawal intention and analyzed such mechanism by constructing a structural equation model.The results indicated that:1)rural homestead vacancy rates increased with distance from the village to the city.2)rural-settled farmers showed a low withdrawal intention for vacant rural homesteads,followed by urban and rural dual-residence farmers,and urban-settled farmers showed the highest withdrawal intention.3)the relative importance of the factors influencing withdrawal intention is in the following order:policy awareness>interest perception>living environment perception>family characteristics.Finally,this study discussed the reformation of the homestead system and rural homestead transition in Northeast China,which can provide policy support to increase the potential of cultivated land and promote sustainable rural development and urban-rural coordination.

Extreme meteorological disaster effects on grain production in Jilin Province, China

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.

Types and Spatial Distribution of Geo-tourism Resources in Jilin Province of China

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.

Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse observation.Hence,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD variations.The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/yr.In snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air temperature.The correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and March.In March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo counties.However,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

Present situation and prospects of forest ecological network in Jilin Province, China

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.

Ginkgo from Lower Cretaceous Changcai Formation in Helong of Jilin, NE China

Based on gross morphological and cuticular study, two species of Ginkgo From the Lower Cretaceous Changcai Formation in Helong of Jilin. were identified from this area for the first time, including Ginkgo coriacea Florin and G.sibiricaHeer. The study is significant for better understanding the paleophytogeographic, paleoecologicandstratigraphic characters of the Early Cretaceous Changcai flora.

The First Vertebrate Assemblage Dominated by Fishes and Turtles of the Jehol Biota in Jilin Province, NE China

Objective The Early Cretaceous sediments are well-exposed in southern Jilin Province,and yield abundant invertebrate and plant fossils,including the typical EosestheriaEphemeropsis trisetalis-Lycoptera（E-E-L）assemblage of the Jehol Biota（Shao Tiequan et al.,2017）.However,vertebrate fossils,especially tetrapods,are extremely rare and there is no formal documents on these fossils.Recently,a new fossil site dominated by fishes and turtles has been discovered in the middle part of the

Comparison of energy consumption and economic performance of organic and conventional soybean production——A case study from Jilin Province, China

Modern agriculture heavily depends on energy consumption, especially fossil energy, but intensive energy input increases the production cost for producers and results in environmental pollution.Organic agricultural production is considered a more sustainable system, but there is lack of scientific research on the energy consumption between organic and conventional systems in China.The analysis and comparison of energy use between the two systems would help decision-makers to establish economic, effective and efficient agricultural production.Thus, the objectives of the present study are to analyze energy inputs, outputs, energy efficiency, and economic benefits between organic and conventional soybean（Glycine max（L.） Merrill） production.A total of 24 organic farmers and 24 conventional farmers in Jilin Province, China, were chosen for investigation in 2010 production year.Total energy input was 71.55 GJ ha–1 and total energy output was 96.18 GJ ha–1 in the organic system, resulting in an energy efficiency（output/input） of 1.34.Total energy input was 9.37 GJ ha–1 and total energy output was 113.4 GJ ha–1 in the conventional system, resulting in the energy efficiency of 12.1.The huge discrepancy in energy inputs and respective efficiencies lies in the several times higher nutrient inputs in the organic compared to the conventional production system.Finally, the production costs ha–1 were 33% higher, and the net income ha–1 25% lower in the organic compared to the conventional soybean production system.It is recommended to improve fertilizer management in organic production to improve its energetic and economic performance.

Ecological Footprint and Major Driving Forces in West Jilin Province, Northeast China

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.

Spatiotemporal Variations and Influencing Factors Analysis of PM_(2.5) Concentrations in Jilin Province,Northeast China

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.

Changing Rural Development Inequality in Jilin Province, Northeast China

Rural development inequality is an important practical issue during the course of full establishment of a ′moderately well-off society′ in modern China,and the objective understanding and evaluation of the status and regional inequality of rural development can provide scientific basis for ′building a new countryside′ and coordination development of rural-urban regions.Based on the county-level data of 2000,2005 and 2009,this paper examines the rural development inequality of Jilin Province in Northeast China by establishing a rural development index.The spatio-temporal dynamic patterns and domain factors are discussed by using the method of exploratory spatial data analysis and multi-regression model.The results are shown as follows.Firstly,most of the counties were in lower development level,which accounted for 58.3%,62.5% and 66.7% of the total counties in 2000,2005 and 2009,respectively.The characteristics of spatial inequality were very obvious at county level.For example,rural development level of Changchun Proper and the proper of seven prefecture-level cities were much higher than that of the surrounding regions.The counties in the eastern and northern Jilin Province were the lowest regions of rural development level,while the middle counties were the rapid growth areas in rural economy.Secondly,Moran′s I of rural development index(RDI) was 0.01,–0.16 and –0.06 in 2000,2005 and 2009,respectively,which indicated that spatial agglomeration of RDI was not obvious in Jilin Province,and took on the characteristic of random distribution.The counties of both the units and its adjacent units have higher development level(HH) were transferred from the western areas to the eastern areas,while the countries of both the units and its adjacent units have lower development level(LL) were diffused from the eastern to middle and western Jilin Province.Finally,the result of multi-regression analysis showed that the improvement of agricultural production condition,development of agricultural economics and the adjustment of industrial structure were the domain factors affecting rural development inequality of Jilin Province in the later ten years.

Integrated Techniques of Underground CO_2 Storage and Flooding Put into Commercial Application in the Jilin Oilfield, China

Global warming touches everybody＇s nerve, and direct reason for sharp increasing of CO2 in the atmosphere results mainly from the use of fossil fuel in power generation and other industries. How can humans return this ＂devil＂ to underground, and keep a peaceful environment for human？ Scientists from all over the world have been exploring them.

FORMATION MECHANISM AND SPATIAL PATTERN OF URBAN AGGLOMERATION IN CENTRAL JILIN OF CHINA

Urban agglomeration is made up of cities with different sizes to be linked by traffic network in a given area, and it is an inevitable result when urbanization reaches a certain level. Taking urban agglomeration in central Jilin (UACJ) as an example, this article analyzes the formation mechanism and spatial pattern of urban agglomeration in the less-developed area. First, the dynamics of UACJ has been analyzed from the aspects of geographical condition, economic foundation, policy background, and traffic condition. Then the development process is divided into three stages-single city, city group and city cluster. Secondly, the central cities are identified from the aspects of city cen- trality, and the development axes are classified based on economic communication capacity. Finally, the urban agglo- meration is divided into five urban economic regions in order to establish the reasonable distribution of industries.

Zircon U-Pb Age of the Lamenzi Formation Volcanic Rocks in the Liuhe Basin of Southern Jilin Province, China

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

Grey-relation Analysis of Traffic System and Urbanization in Jilin Province of China

It has been long believed there should be some relations between traffic system and urbanization,but the in-teraction between them,especially on the regional level,has been not in consideration due to the difficulty in quantitative analysis.Based on the development of Jilin Province during 1981-2003,the paper analyzed the relation with the grey-relation model which was adjusted to fit specific problem,and came to some conclusions.Firstly,there exists ob-vious and strong correlation between traffic system and urbanization.Secondly,urbanization responds to the develop-ment of traffic system mainly on the level of urbanization,such as population and developed area,however,less on urbanization quality.Thirdly,traffic system influences urbanization as a whole except for several peculiar factors,which means we should optimize the whole traffic system to promote urbanization.Based on those conclusions,the paper illustrated the mechanism of traffic system,promoting urbanization scale and urbanization quality.

EVALUATION OF ECOLOGICAL SERVICES OF JILIN PROVINCE, NORTHEAST CHINA

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.

Relationship between Migration and HIV Risky Behavior: a Comparative Study of Returning Migrants and Non Migrants Based on Rural Out-of-school Youth in Jilin, China

Objective To estimate the relationship between migration and HIV risky behavior when controlling for gender, age, and educational levels and to evaluate the gender differences in migration, HIV knowledge, and HIV risky behaviors among rural youth in China. Methods A cross-sectional, anonymous, investigative questionnaire for 1710 unmarried, out-of-school rural youth, aged between 15 and 24 years, was handed out in Gongzhuling county of Jilin province, China. Results 58.5% of participants had a history of migration, irrespective of gender. There were gender differences observed in other factors such as drug abuse（4.3% for males and 5.5% for females, P〈0.01）, multiple sexual partners（24.1% for males and 44.1% for females, P〈0.01）, and HIV knowledge rate（35.2% for males and 25.5% for females, P〈0.001）. While controlling for gender, age, and educational levels, the relationships between migration and drug abuse, selling sex, and non usage of condoms during last instance of sexual activity were found to be significant. The cases of premarital sex and multiple sexual partners were both not found to be related to migration. Conclusion Among rural youth, the HIV risky behavior such as drug abuse, selling sex, and lack of condom use, is significantly related to migration, while premarital sex and multiple sexual partners seem unrelated to migration.

The Interaction of Population,Industry and Land in Process of Urbanization in China:A Case Study in Jilin Province

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.