We report new material of the zalambdalestid,Zhangolestes jilinensis,from the Quantou Formation(lower Upper Cretaceous,Cenomanian to Turonian),Gongzhuling City,Jilin Province,NE China.Using micro-CT-scan,the material ...We report new material of the zalambdalestid,Zhangolestes jilinensis,from the Quantou Formation(lower Upper Cretaceous,Cenomanian to Turonian),Gongzhuling City,Jilin Province,NE China.Using micro-CT-scan,the material is shown to include dentocranial and postcranial elements recovered from the same matrix block containing the holotype specimen.The CT-images also show the labial and internal structures of the holotype fragment of the lower jaw of Z.jilinensis.Based on the preservation,relative size,and tooth wear,the new material and the holotype lower jaw likely belong to the same individual animal,whereas the hypodigm mandibular fragment assigned to Z.jilinensis in the original study is thought now to belong to a different individual,potentially representing a different species,which,if true,would increase the eutherian diversity in the Late Cretaceous Changchunsaurus Fauna.Furthermore,the new CT-images show that the incisor morphology is diverse within zalambdalestids and probably evolved independently from the enlarged incisors in placental mammals,such as Glires.展开更多
Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·...Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·Mg2+ or HCO3--Mg2+·Ca2+; SO42--Ca2+ and SO42--Ca2+·Mg2+; Cl--Ca2+; and CO32--Na+. The deteriorations of groundwater quality due to the increase of TDS, NO3-+ NO2-(as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl-and NO3-ions and weak negative correlations between the depth of water table and Ca2+, SO42-, Cl-and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2-and Mn2+ ions.展开更多
In China and East Asia,the long-term continuous observational data at daily resolution are insufficient,and thus there is a lack of good understanding of the extreme climate variation over the last 100 years plus.In t...In China and East Asia,the long-term continuous observational data at daily resolution are insufficient,and thus there is a lack of good understanding of the extreme climate variation over the last 100 years plus.In this study,the extreme temperature indices defined by ETCCDI(Expert Team on Climate Change Detection and Indices)and local meteorological administrations were analyzed for Changchun City,Northeast China,by using the daily maximum temperature(Tmax)and daily minimum temperature(Tmin)over 1909?2018.The results showed that extreme cold events,such as cold days,cold nights,frost days,icing days,and low temperature days,decreased significantly at rates of?0.41 d(10 yr)^?1,?1.45 d(10 yr)^?1,?2.28 d(10 yr)^?1,?1.16 d(10 yr)?1 and?1.90 d(10 yr)^?1,respectively.Warm nights increased significantly at a rate of 1.71 d(10 yr)^?1,but warm days decreased slightly and the number of high temperature days decreased at a rate of?0.20 d(10 yr)?1.The frequency of cold surge events increased significantly at a rate of 0.25 d(10 yr)^?1,occurring mainly from the mid-1950s to late-1980s.The average Tmax,average Tmin and extreme Tmin increased at rates of 0.09℃(10 yr)^?1,0.36℃(10 yr)^?1 and 0.54℃(10 yr)^?1,respectively;and extreme Tmax decreased significantly at a rate of?0.17℃(10 yr)^?1.In 1909?2018,1951?2018 and 1979?2018,the indices related to cold events decreased,while the trends of the indices related to warm events were different for different periods.展开更多
Urbanization,especially urban land expansion,has a profound influence on the urban thermal environment.Cities in Northeast China face remarkably uneven development and environmental issues,and thus it is necessary to ...Urbanization,especially urban land expansion,has a profound influence on the urban thermal environment.Cities in Northeast China face remarkably uneven development and environmental issues,and thus it is necessary to strengthen the diagnosis of thermal environmental pressure brought by urbanization.In this study,multi remote sensing imageries and statistical approaches,involving piecewise linear regression(PLR),were used to explore urban expansion and its effects on the thermal environment of Changchun City in Jilin Province,China.Results show that Changchun experienced rapid urban expansion from 2000 to 2020,with urban built-up areas increasing from 171.77 to 525.14 km^(2).The area of the city’s urban heat island(UHI)increased dramatically,during both day and night.Using PLR,a positive linear correlation of built-up density with land surface temperature(LST)was detected,with critical breakpoints of 70%-80%during the daytime and 40%-50%at nighttime.Above the thresholds,the magnitude of LST in response to built-up density significantly increased with intensifying urbanization,especially for nighttime LST.An analysis of the relative frequency distributions(RFDs)of LST reveals that rapid urbanization resulted in a significant increase of mean LST in newly urbanized areas,but had weak effects on daytime LST change in existing urban area.Urban expansion also contributed to a constant decrease of spatial heterogeneity of LST in existing urban area,especially at daytime.However,in newly urbanized areas,the spatial heterogeneity of LST was decreased during the daytime but increased at nighttime due to urbanization.展开更多
In this paper,we study the interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure.We build an index system for evaluating the agglomeration of urban elemen...In this paper,we study the interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure.We build an index system for evaluating the agglomeration of urban elements and eco-environmental pressure.Using the entropy method and response intensity model,we analyze how urban elements agglomeration influenced eco-environmental pressure in Changchun from 1990 to 2012,eliciting the changing features and influential factors.Ultimately,we conclude there is a significant interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure in Changchun.This is inferred from the degree of this agglomeration in Changchun having increased since 1990,with the degree of eco-environmental pressure first decreasing and then increasing.Alongside this,the impact of urban elements agglomeration on eco-environmental pressure has changed from negative to positive.The main reasons behind this shift are arguably the rapid growth of urban investment and ongoing urbanization.展开更多
The calcite mylonites in the Xar Moron-Changchun shear zone show a significance dextral shearing characteristics. The asymmetric(σ-structure) calcite/quartz grains or aggregates, asymmetry of calcite c-axes fabric di...The calcite mylonites in the Xar Moron-Changchun shear zone show a significance dextral shearing characteristics. The asymmetric(σ-structure) calcite/quartz grains or aggregates, asymmetry of calcite c-axes fabric diagrams and the oblique foliation of recrystallized calcite grains correspond to a top-to-E shearing. Mineral deformation behaviors, twin morphology, C-axis EBSD fabrics, and quartz grain size-frequency diagrams demonstrate that the ductile shear zone was developed under conditions of greenschist facies, with the range of deformation temperatures from 200 to 300°C. These subgrains of host grains and surrounding recrystallized grains, strong undulose extinction, and slightly curved grain boundaries are probably results of intracrystalline deformation and dynamic recrystallization implying that the deformation took place within the dislocation-creep regime at shallow crustal levels. The calculated paleo-strain rates are between 10-7.87s-1 and 10-11.49s-1 with differential stresses of 32.63-63.94 MPa lying at the higher bound of typical strain rates in shear zones at crustal levels, and may indicate a relatively rapid deformation. The S-L-calcite tectonites have undergone a component of uplift which led to subhorizontal lifting in an already non-coaxial compressional deformation regime with a bulk pure shear-dominated general shear. This E-W large-scale dextral strike-slip movement is a consequence of the eastward extrusion of the Xing’an-Mongolian Orogenic Belt, and results from far-field forces associated with Late Triassic convergence domains after the final closure of the Paleo-Asian Ocean.展开更多
On analyzing the achievement of the goal in the modem urban road traffic development planning, the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme, the exte...On analyzing the achievement of the goal in the modem urban road traffic development planning, the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme, the extended scheme and the environmental protection scheme. This study from different perspectives designed the alternatives for Changchun＇s county-level road and urban road system planning, and used the method of System Dynamics to simulate, optimize and analyze those alternatives. Thereafter, some methods including the correlation function method were used to comprehensively assess and rank those alternatives for recommending two best alternatives with the consideration to the indicators, such as the total emission amount of CO, the total emission amount of nitrogen oxides, the noise value, the road construction cost, the fossil oil consumption and the traffic capacity. The result showed that the study would provide substantial supports for decision-makers to make more scientific decisions and promote the sustainable urban traffic in Changchun City.展开更多
A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with sn...A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with snow provides the best samples to conduct a quantitative research on the possible impacts of city - ecology. In the 253km2 urban district area of Changchun city, smallsands accumulated up to more than 3000t on April 7, according to the calculation of four "mud - snow" samples. After naturally melting in room temperature, two samples are taken to do quarantine of "invasion bacteria". As a preliminary result, the individual amount of bacterium in 1 ml sample water is up to 8. 9 x 104 or 1. 05 x 105, and it is estimated that there are 640 million "invasion bacterium" individuals in one square meter. This study proves that other than the obvious environmental effects of sandstorm, the urban micro - ecosystem is very possible under threat by the "invasion bacterium" accompanied by remote descending smallsand.展开更多
Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an i...Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an important agricultural base. Additionally, Changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complex- ity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index （AQI） level-1 standard （AQI 〉50） according to the National Ambient Air Quality Standard （NAAQS） of China. Conversely, 33.7% of the days showed a higher level with AQI 〉 100. Ex- treme haze events （AQI 〉 300） occurred frequently during agricultural harvesting period （from October 10 to November 10）, intensive winter heating period （from Late-December to February） and period of spring windblown dust （April and May）. Most daily concentra- tions of gaseous pollutants, i.e., NO2 （43.8 gg/m3）, CO （0.9 mg/m3）, SO2 （37.9 gg/m3）, and 03 （74.9 gg/m3） were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter （PM2.5 and PMI0） concentrations （67.3 ~tg/m3and 115.2 ~g/m3, respectively） were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions （i.e., low wind speed and inversion layer）. The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was the primary component of total emissions. In addition, general emissions including automobile exhaust, road and construction dust, residential and industrial activities, have significantly increased in recent years, making heavy haze a more frequent occurrence. There- fore, both improved technological strategies and optimized pollution management on a regional scale are necessary to minimize emis- sions in specified seasons in Changchun City, as well as comprehensive control measures in Northeast China.展开更多
In China, seasonal frozen soil is widely distributed. The freezing damage of subgrade soil in Jilin Province has been one of major engineering geological problems troubling the safety of road, in which some common dam...In China, seasonal frozen soil is widely distributed. The freezing damage of subgrade soil in Jilin Province has been one of major engineering geological problems troubling the safety of road, in which some common damage phenomena, such as frost heave, subsidence deformation and frost boiling, are all caused by water translocation. Aiming at the phenomenon, the changes of moisture content of seasonal frozen soil in Changchun City are mainly studied by long-term field observation and indoor testing of physical properties under different conditions, and then the variation characteristics of moisture content in soil under different compactness and temperature conditions are realized. The results show that the increasing section of moisture content and negative temperature section all lie in O. 0 - 1.0 m of subgrade. Both lowest air and earth temperature occur in January to February, and the most negative temperature ranges from -7℃ to -10℃.展开更多
To gain a better understanding of the characteristics of air pollution of Changchun city, P. R. China, in summer, the analytical methods of geographical information system（GIS） and statistical analysis software SPSS...To gain a better understanding of the characteristics of air pollution of Changchun city, P. R. China, in summer, the analytical methods of geographical information system（GIS） and statistical analysis software SPSS were applied to the analysis of the monitored concentrations of SO2 , NO2, and O3 in July of 2002 to 2004 in Changchun city. The results obtained show that the average hourly O3 concentrations in July 2002 and 2004 were higher than the firstlevel hourly standard of China. At the same time, the dynamic distribution of the 03 concentration and the relationship between the concentration of 03 and that of NOx were studied. The air quality evaluation result of Changchun city indicates that the southwest of this city was heavily polluted during the monitored period.展开更多
The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially ow...The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially owing to technical requirement for shallow terrestrial heat recently, it directly influenced the design and solution in engineering problems. The authors measured the STC in the studied area with QTM-D2 and discussed the effect of samples in size, the measurement error between the samples in lab and in site. The results indicate measuring STC by heat pole method with less influence upon the samples in size, and measuring results on the different geometry size approach very much. The STC is fit for the empirical relation between the temperature and TC under the condition of normal temperature. It is significance for understanding STC in northern China and simulation of temperature field.展开更多
Since the State Council approved the development plan of the Harbin-Changchun Urban Agglomeration in 2016, the development of the Harbin-Changchun Urban Agglomeration has received extensive attention from the society....Since the State Council approved the development plan of the Harbin-Changchun Urban Agglomeration in 2016, the development of the Harbin-Changchun Urban Agglomeration has received extensive attention from the society. Starting from the perspective of "three-life space" and referring to the existing research results, this paper determines the three-life space classification system of Harbin-Changchun urban agglomeration, analyzes the problems faced by its "production-life-ecology" space in the development process, and puts forward optimization suggestions for the problems.展开更多
Food quality is the important content of food security and a major issue related to the national economy and people's livelihood.At present,with the enhancement of economic strength and the improvement of income l...Food quality is the important content of food security and a major issue related to the national economy and people's livelihood.At present,with the enhancement of economic strength and the improvement of income level,people pay more attention to the quality of life and physical health,so food quality has become the focus of social concern gradually.展开更多
An extensive soil investigation was conducted in different domains of Changchun to disclose the fractionations of Pb, Cu, Cd, Zn and Ni in urban soils. Meanwhile correlation analysis and multiple stepwise regressions ...An extensive soil investigation was conducted in different domains of Changchun to disclose the fractionations of Pb, Cu, Cd, Zn and Ni in urban soils. Meanwhile correlation analysis and multiple stepwise regressions were used to define relationships between soil properties and metal fractions and the chief factors influencing the fractionation of heavy metals in the soils. The results showed that Pb, Ni and Cu were mainly associated with the residual and organic forms; most of Cd was concentrated in the residual and exchangeable fractions. Zn in residual and carbonate fraction was the highest. The activities of the heavy metals probably declined in the following order: Cd, Zn, Pb, Cu and Ni. The chemical fractions of heavy metals in different domains in Changchun City were of significantly spatial heterogeneity. Soil properties had different influences on the chemical fractions of heavy metals to some extent and the main factors influencing Cd, Zn, Pb, Cu and Ni fractionation and transformation were apparently different.展开更多
The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-m...The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.展开更多
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban...Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.展开更多
Aim： To investigate possible correlation factors for prostate cancer by a population-based case-control study in China. Methods： We carded out a mass screening of prostate cancer in Changchun, China, using a prostat...Aim： To investigate possible correlation factors for prostate cancer by a population-based case-control study in China. Methods： We carded out a mass screening of prostate cancer in Changchun, China, using a prostate-specific antigen assisted by Japan International Cooperation Agency. From June 1998 to December 2000, 3 940 men over 50 years old were screened. Of these, 29 men were diagnosed with prostate cancer. We selected 28 cases and matched them with controls of low prostate-specific antigen value （〈 4.1 ng/mL） by 1：10 according to age and place of employment. A case-control study of diet and prostate cancer was then carded out. Results： After adjustment for education, body mass index （BMI）, smoking, alcohol consumption, marriage and diet, intake of soybean product was discovered to be inversely related to prostate cancer. Men who consumed soybean product more than twice per week on different days had a multivariate odds ratio （OR） of 0.38 （95% confidence interval [CI], 0.13-1.12）. In addition, men who consumed soybean products more than once per day had a multivariate OR of 0.29 （95% CI, 0.11-0.79） compared with men who consumed soybean products less than once per week. The P for trend was 0.02, which showed significant difference. There was no significant difference in P trend for any dairy food. Even when we matched the cases and controls by other criteria, we found that soybean food was the only preventive factor associated with prostate cancer. Conclusion： Our study suggests that consumption of soybeans, one of the most popular foods in Asia, would decrease the risk of prostate cancer.展开更多
Depending on various government policies,COVID-19(Corona Virus Disease-19) lockdowns have had diverse impacts on global aerosol concentrations.In 2022,Changchun a provincial capital city in Northeast China,suffered a ...Depending on various government policies,COVID-19(Corona Virus Disease-19) lockdowns have had diverse impacts on global aerosol concentrations.In 2022,Changchun a provincial capital city in Northeast China,suffered a severe COVID-19 outbreak and implemented a very strict lockdown that lasted for nearly two months.Using ground-based polarization Light Detection and Ranging(LiDAR),we detected real-time aerosol profile parameters(EC,extinction coefficient;DR,depolarization ratio;AOD,aerosol optical depth),as well as air-quality and meteorological indexes from 1 March to 30 April in 2021 and 2022 to quantify the effects of lockdown on aerosol concentrations.The period in 2022 was divided into three stages:pre-lockdown(1-10 March),strict lockdown(11 March to 10 April),and partial lockdown(11-30 April).The results showed that,during the strict lockdown period,compared with the pre-lockdown period,there were substantial reductions in aerosol parameters(EC and AOD),and this was consistent with the concentrations of the atmospheric pollutants PM_(2.5)(particulate matter with an aerodynamic diameter ≤2.5 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter ≤10 μm),and the Oconcentration increased by 8.3%.During the strict lockdown,the values of EC within0-1 km and AOD decreased by 16.0% and 11.2%,respectively,as compared to the corresponding period in 2021.Lockdown reduced the conventional and organized emissions of air pollutants,and it clearly delayed the time of seasonal emissions from agricultural burning;however,it did not decrease the number of farmland fire points.Considering meteorological factors and eliminating the influence of wind-blown dust events,the results showed that reductions from conventional organized emission sources during the strict lockdown contributed to a 30% air-quality improvement and a 22% reduction in near-surface extinction(0-2 km).Aerosols produced by urban epidemic prevention and disinfection can also be identified using the EC.Regarding seasonal sources of agricultural straw burning,the concentrated burning induced by the epidemic led to the occurrence of heavy pollution from increased amounts of atmospheric aerosols,with a contribution rate of 62%.These results indicate that there is great potential to further improve air quality in the local area,and suggest that the comprehensive use of straw accompanied by reasonable planned burning is the best way to achieve this.展开更多
Using a bottom-up estimation method,a comprehensive,high-resolution emission inventory of gaseous and particulate atmospheric pollutants for multiple anthropogenic sectors with typical local sources has been developed...Using a bottom-up estimation method,a comprehensive,high-resolution emission inventory of gaseous and particulate atmospheric pollutants for multiple anthropogenic sectors with typical local sources has been developed for the Harbin-Changchun city agglomeration(HCA).The annual emissions for CO,NO_(x),SO_(2),NH_(3),VOC S,PM_(2.5),PM 10,BC and OC during 2017 in the HCA were estimated to be 5.82 Tg,0.70 Tg,0.34 Tg,0.75 Tg,0.81 Tg,0.67 Tg,1.59 Tg,0.12 Tg and 0.26 Tg,respectively.For PM 10 and SO_(2),the emissions from industry processes were the dominant contributors representing 54.7%and 49.5%,respectively,of the total emissions,while 95.3%and 44.5%of the total NH_(3)and NO x emissions,respectively,were from or associated with agricultural activities and transportation.Spatiotemporal distributions showed that most emissions(except NH_(3))occurred in November to March and were concentrated in the central cities of Changchun and Harbin and the surrounding cities.Open burning of straw made an important contribution to PM_(2.5)in the central regions of the northeastern plain during autumn and spring,while domestic coal combustion for heating purposes was significant with respect to SO_(2)and PM_(2.5)emissions during autumn and winter.Furthermore,based on Principal Component Analysis and Multivariable Linear Regression model,air temperature,relative humidity,electricity and energy consumption,and the urban and rural population were optimized to be representative indicators for rapidly assessing the magnitude of regional atmospheric pollutants in the HCA.Such indicators and equations were demonstrated to be useful for local atmospheric environment management.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42122010,42072017)the Youth Innovation Promotion Association CAS(Y2023017)+1 种基金the National Mineral Rock and Fossil Specimens Resource Center(NCSTI-RMF20240203)China Geological Survey(DD20230221)。
文摘We report new material of the zalambdalestid,Zhangolestes jilinensis,from the Quantou Formation(lower Upper Cretaceous,Cenomanian to Turonian),Gongzhuling City,Jilin Province,NE China.Using micro-CT-scan,the material is shown to include dentocranial and postcranial elements recovered from the same matrix block containing the holotype specimen.The CT-images also show the labial and internal structures of the holotype fragment of the lower jaw of Z.jilinensis.Based on the preservation,relative size,and tooth wear,the new material and the holotype lower jaw likely belong to the same individual animal,whereas the hypodigm mandibular fragment assigned to Z.jilinensis in the original study is thought now to belong to a different individual,potentially representing a different species,which,if true,would increase the eutherian diversity in the Late Cretaceous Changchunsaurus Fauna.Furthermore,the new CT-images show that the incisor morphology is diverse within zalambdalestids and probably evolved independently from the enlarged incisors in placental mammals,such as Glires.
文摘Groundwater in Changchun City, Jilin Province of China tends to be influenced by human activities. Chemical types of groundwater were detected in both shallow and deep groundwater were: HCO3--Ca2+ and HCO3--Ca2+·Mg2+ or HCO3--Mg2+·Ca2+; SO42--Ca2+ and SO42--Ca2+·Mg2+; Cl--Ca2+; and CO32--Na+. The deteriorations of groundwater quality due to the increase of TDS, NO3-+ NO2-(as Nitrogen) and TH contents have been observed from 1991 to 1998. Scatter analyses showed strong positive correlations between Ca2+, Cl-and NO3-ions and weak negative correlations between the depth of water table and Ca2+, SO42-, Cl-and NO3-ions. A mapping of contaminant index based on Chinese standard of groundwater showed that a large proportion of the groundwater in 1998 was deteriorated by human process. Despite their low values of sodium adsorption ratio (SAR), the most of the sampled wells were not suitable for drinking and agriculture purposes due to higher contents of NO3-, NO2-and Mn2+ ions.
基金the National Key R&D Program of China(Grant No.2018YFA0605603).
文摘In China and East Asia,the long-term continuous observational data at daily resolution are insufficient,and thus there is a lack of good understanding of the extreme climate variation over the last 100 years plus.In this study,the extreme temperature indices defined by ETCCDI(Expert Team on Climate Change Detection and Indices)and local meteorological administrations were analyzed for Changchun City,Northeast China,by using the daily maximum temperature(Tmax)and daily minimum temperature(Tmin)over 1909?2018.The results showed that extreme cold events,such as cold days,cold nights,frost days,icing days,and low temperature days,decreased significantly at rates of?0.41 d(10 yr)^?1,?1.45 d(10 yr)^?1,?2.28 d(10 yr)^?1,?1.16 d(10 yr)?1 and?1.90 d(10 yr)^?1,respectively.Warm nights increased significantly at a rate of 1.71 d(10 yr)^?1,but warm days decreased slightly and the number of high temperature days decreased at a rate of?0.20 d(10 yr)?1.The frequency of cold surge events increased significantly at a rate of 0.25 d(10 yr)^?1,occurring mainly from the mid-1950s to late-1980s.The average Tmax,average Tmin and extreme Tmin increased at rates of 0.09℃(10 yr)^?1,0.36℃(10 yr)^?1 and 0.54℃(10 yr)^?1,respectively;and extreme Tmax decreased significantly at a rate of?0.17℃(10 yr)^?1.In 1909?2018,1951?2018 and 1979?2018,the indices related to cold events decreased,while the trends of the indices related to warm events were different for different periods.
基金Under the auspices of the Natural Science Foundation of Jilin Province(No.20200201048JC)。
文摘Urbanization,especially urban land expansion,has a profound influence on the urban thermal environment.Cities in Northeast China face remarkably uneven development and environmental issues,and thus it is necessary to strengthen the diagnosis of thermal environmental pressure brought by urbanization.In this study,multi remote sensing imageries and statistical approaches,involving piecewise linear regression(PLR),were used to explore urban expansion and its effects on the thermal environment of Changchun City in Jilin Province,China.Results show that Changchun experienced rapid urban expansion from 2000 to 2020,with urban built-up areas increasing from 171.77 to 525.14 km^(2).The area of the city’s urban heat island(UHI)increased dramatically,during both day and night.Using PLR,a positive linear correlation of built-up density with land surface temperature(LST)was detected,with critical breakpoints of 70%-80%during the daytime and 40%-50%at nighttime.Above the thresholds,the magnitude of LST in response to built-up density significantly increased with intensifying urbanization,especially for nighttime LST.An analysis of the relative frequency distributions(RFDs)of LST reveals that rapid urbanization resulted in a significant increase of mean LST in newly urbanized areas,but had weak effects on daytime LST change in existing urban area.Urban expansion also contributed to a constant decrease of spatial heterogeneity of LST in existing urban area,especially at daytime.However,in newly urbanized areas,the spatial heterogeneity of LST was decreased during the daytime but increased at nighttime due to urbanization.
基金Under the auspices of Education Ministry for Development of Liberal Arts and Social Science(No.14YJA790035)
文摘In this paper,we study the interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure.We build an index system for evaluating the agglomeration of urban elements and eco-environmental pressure.Using the entropy method and response intensity model,we analyze how urban elements agglomeration influenced eco-environmental pressure in Changchun from 1990 to 2012,eliciting the changing features and influential factors.Ultimately,we conclude there is a significant interactive relationship between the agglomeration of urban elements and the evolution of eco-environmental pressure in Changchun.This is inferred from the degree of this agglomeration in Changchun having increased since 1990,with the degree of eco-environmental pressure first decreasing and then increasing.Alongside this,the impact of urban elements agglomeration on eco-environmental pressure has changed from negative to positive.The main reasons behind this shift are arguably the rapid growth of urban investment and ongoing urbanization.
基金financially co-supported by the National Key R&D Program of China (Grant No.2017YFC0601401 and 2017YFC0601300-01)the National Natural Science Foundation of China (Grant no. 41602211 and 41230206)
文摘The calcite mylonites in the Xar Moron-Changchun shear zone show a significance dextral shearing characteristics. The asymmetric(σ-structure) calcite/quartz grains or aggregates, asymmetry of calcite c-axes fabric diagrams and the oblique foliation of recrystallized calcite grains correspond to a top-to-E shearing. Mineral deformation behaviors, twin morphology, C-axis EBSD fabrics, and quartz grain size-frequency diagrams demonstrate that the ductile shear zone was developed under conditions of greenschist facies, with the range of deformation temperatures from 200 to 300°C. These subgrains of host grains and surrounding recrystallized grains, strong undulose extinction, and slightly curved grain boundaries are probably results of intracrystalline deformation and dynamic recrystallization implying that the deformation took place within the dislocation-creep regime at shallow crustal levels. The calculated paleo-strain rates are between 10-7.87s-1 and 10-11.49s-1 with differential stresses of 32.63-63.94 MPa lying at the higher bound of typical strain rates in shear zones at crustal levels, and may indicate a relatively rapid deformation. The S-L-calcite tectonites have undergone a component of uplift which led to subhorizontal lifting in an already non-coaxial compressional deformation regime with a bulk pure shear-dominated general shear. This E-W large-scale dextral strike-slip movement is a consequence of the eastward extrusion of the Xing’an-Mongolian Orogenic Belt, and results from far-field forces associated with Late Triassic convergence domains after the final closure of the Paleo-Asian Ocean.
基金Under the auspices of Major State Basic Research Development Program of China (973 Program) (No. 2005CB724205)Science Foundation Programme for Young Teachers of Northeast Normal University (No. 20070503)
文摘On analyzing the achievement of the goal in the modem urban road traffic development planning, the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme, the extended scheme and the environmental protection scheme. This study from different perspectives designed the alternatives for Changchun＇s county-level road and urban road system planning, and used the method of System Dynamics to simulate, optimize and analyze those alternatives. Thereafter, some methods including the correlation function method were used to comprehensively assess and rank those alternatives for recommending two best alternatives with the consideration to the indicators, such as the total emission amount of CO, the total emission amount of nitrogen oxides, the noise value, the road construction cost, the fossil oil consumption and the traffic capacity. The result showed that the study would provide substantial supports for decision-makers to make more scientific decisions and promote the sustainable urban traffic in Changchun City.
文摘A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with snow provides the best samples to conduct a quantitative research on the possible impacts of city - ecology. In the 253km2 urban district area of Changchun city, smallsands accumulated up to more than 3000t on April 7, according to the calculation of four "mud - snow" samples. After naturally melting in room temperature, two samples are taken to do quarantine of "invasion bacteria". As a preliminary result, the individual amount of bacterium in 1 ml sample water is up to 8. 9 x 104 or 1. 05 x 105, and it is estimated that there are 640 million "invasion bacterium" individuals in one square meter. This study proves that other than the obvious environmental effects of sandstorm, the urban micro - ecosystem is very possible under threat by the "invasion bacterium" accompanied by remote descending smallsand.
基金Under the auspices of National Key Research and Development Project(No.2017YFC0212300)Youth Innovation Promotion Association CAS(No.2017275)Frontier Science Research Plan CAS(No.QYZDB-SSW-DQC045)
文摘Northeast China has been reported as having serious air pollution in China with increasing occurrences of severe haze epi- sodes. Changchun City, as the center of Northeast China, has longstanding industry and is an important agricultural base. Additionally, Changchun City has a long winter requiring heating of buildings emitting pollution into the air. These factors contribute to the complex- ity of haze pollution in this area. In order to analyze the causes of heavy haze, surface air quality has been monitored from 2013 to 2015. By using satellite and meteorological data, atmospheric pollution status, spatio-temporal variations and formation have been analyzed. Results indicated that the air quality in 88.9% of days exceeding air quality index （AQI） level-1 standard （AQI 〉50） according to the National Ambient Air Quality Standard （NAAQS） of China. Conversely, 33.7% of the days showed a higher level with AQI 〉 100. Ex- treme haze events （AQI 〉 300） occurred frequently during agricultural harvesting period （from October 10 to November 10）, intensive winter heating period （from Late-December to February） and period of spring windblown dust （April and May）. Most daily concentra- tions of gaseous pollutants, i.e., NO2 （43.8 gg/m3）, CO （0.9 mg/m3）, SO2 （37.9 gg/m3）, and 03 （74.9 gg/m3） were evaluated within level-1 concentration limits of NAAQS standards. However, particulate matter （PM2.5 and PMI0） concentrations （67.3 ~tg/m3and 115.2 ~g/m3, respectively） were significantly higher than their level-1 limits. Severe haze in spring was caused by offsite transported dust and windblown surface soil. Heavy haze periods during fall and winter were mainly formed by intensive emissions of atmospheric pollutants and steady weather conditions （i.e., low wind speed and inversion layer）. The overlay emissions of widespread straw burning and coal combustion for heating were the dominant factors contributing to haze in autumn, while intensive coal burning during the coldest time was the primary component of total emissions. In addition, general emissions including automobile exhaust, road and construction dust, residential and industrial activities, have significantly increased in recent years, making heavy haze a more frequent occurrence. There- fore, both improved technological strategies and optimized pollution management on a regional scale are necessary to minimize emis- sions in specified seasons in Changchun City, as well as comprehensive control measures in Northeast China.
基金Supported by National Natural Science Foundation of China (No.40672180)
文摘In China, seasonal frozen soil is widely distributed. The freezing damage of subgrade soil in Jilin Province has been one of major engineering geological problems troubling the safety of road, in which some common damage phenomena, such as frost heave, subsidence deformation and frost boiling, are all caused by water translocation. Aiming at the phenomenon, the changes of moisture content of seasonal frozen soil in Changchun City are mainly studied by long-term field observation and indoor testing of physical properties under different conditions, and then the variation characteristics of moisture content in soil under different compactness and temperature conditions are realized. The results show that the increasing section of moisture content and negative temperature section all lie in O. 0 - 1.0 m of subgrade. Both lowest air and earth temperature occur in January to February, and the most negative temperature ranges from -7℃ to -10℃.
基金Supported by the Knowledge Innovation Program of CAS(No. KZCX2-SW-117)
文摘To gain a better understanding of the characteristics of air pollution of Changchun city, P. R. China, in summer, the analytical methods of geographical information system（GIS） and statistical analysis software SPSS were applied to the analysis of the monitored concentrations of SO2 , NO2, and O3 in July of 2002 to 2004 in Changchun city. The results obtained show that the average hourly O3 concentrations in July 2002 and 2004 were higher than the firstlevel hourly standard of China. At the same time, the dynamic distribution of the 03 concentration and the relationship between the concentration of 03 and that of NOx were studied. The air quality evaluation result of Changchun city indicates that the southwest of this city was heavily polluted during the monitored period.
文摘The study on soil thermal conductivity (STC) was an important side of research on ground source heat pump technique,geological disposal of high-level radioactive wastes,heat distribution of buried cable. Especially owing to technical requirement for shallow terrestrial heat recently, it directly influenced the design and solution in engineering problems. The authors measured the STC in the studied area with QTM-D2 and discussed the effect of samples in size, the measurement error between the samples in lab and in site. The results indicate measuring STC by heat pole method with less influence upon the samples in size, and measuring results on the different geometry size approach very much. The STC is fit for the empirical relation between the temperature and TC under the condition of normal temperature. It is significance for understanding STC in northern China and simulation of temperature field.
文摘Since the State Council approved the development plan of the Harbin-Changchun Urban Agglomeration in 2016, the development of the Harbin-Changchun Urban Agglomeration has received extensive attention from the society. Starting from the perspective of "three-life space" and referring to the existing research results, this paper determines the three-life space classification system of Harbin-Changchun urban agglomeration, analyzes the problems faced by its "production-life-ecology" space in the development process, and puts forward optimization suggestions for the problems.
文摘Food quality is the important content of food security and a major issue related to the national economy and people's livelihood.At present,with the enhancement of economic strength and the improvement of income level,people pay more attention to the quality of life and physical health,so food quality has become the focus of social concern gradually.
文摘An extensive soil investigation was conducted in different domains of Changchun to disclose the fractionations of Pb, Cu, Cd, Zn and Ni in urban soils. Meanwhile correlation analysis and multiple stepwise regressions were used to define relationships between soil properties and metal fractions and the chief factors influencing the fractionation of heavy metals in the soils. The results showed that Pb, Ni and Cu were mainly associated with the residual and organic forms; most of Cd was concentrated in the residual and exchangeable fractions. Zn in residual and carbonate fraction was the highest. The activities of the heavy metals probably declined in the following order: Cd, Zn, Pb, Cu and Ni. The chemical fractions of heavy metals in different domains in Changchun City were of significantly spatial heterogeneity. Soil properties had different influences on the chemical fractions of heavy metals to some extent and the main factors influencing Cd, Zn, Pb, Cu and Ni fractionation and transformation were apparently different.
文摘The study centers on the necessity,t he workflowand the synthetically in tegrated methods(Principal Compo-nentAnalysis(PCA),AndyticalHierarchy Process(AHP)andFuzzy Comprerhensive Evaluatio n(FCE))ofstrategic environ-ment assessment (SEA)on land-use planning.The whole article includes three main parts:firstly,some attribute database,graphic-base and the spatial transform matrix,which reflect the change of regional land-use pattern,can be ob-tained by GIS technique;secondly,a dopting fitting method of trend-sur face analysis will convert environm ent monitoring data from scattered spots to regular control spots,based on which we can p erform regional environment impact assess-ment;finally,Changchun Economic a nd Technological Developmen Zone is chosen as a case study on land-use pla nning.Through those efforts the results ma y be obtained as follows:1)according to transform matrix,the p ossibility of transforma-tion from one land-use to another can be obtained after the planning is carried out;2)environment quality would change as a result of the change of land-use p attern;3)the SEA on land-use plan is an effecti ve tool to make land-use pattern more reasonable.
基金the Youth Growth Technology Project,Science and Technology Department of Jilin Province(20230508130RC)Bureau of Forestry and Landscaping of Changchun.
文摘Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.
基金We would appreciate the contribution of Prof. Kuwahara （Miyagi Prefecture Cancer Center, Japan） in this project. We would appreciate Mr. Robert Lister＇s critical reading and revision of our manuscript. This research was supported by the National Natural Science Foundation of China （Grant No. 30700827）, Changchun City Science and Technology Department （Grant No. 2007125）, and Northeast Normal University （Grant No. NENU-STC07005）.
文摘Aim： To investigate possible correlation factors for prostate cancer by a population-based case-control study in China. Methods： We carded out a mass screening of prostate cancer in Changchun, China, using a prostate-specific antigen assisted by Japan International Cooperation Agency. From June 1998 to December 2000, 3 940 men over 50 years old were screened. Of these, 29 men were diagnosed with prostate cancer. We selected 28 cases and matched them with controls of low prostate-specific antigen value （〈 4.1 ng/mL） by 1：10 according to age and place of employment. A case-control study of diet and prostate cancer was then carded out. Results： After adjustment for education, body mass index （BMI）, smoking, alcohol consumption, marriage and diet, intake of soybean product was discovered to be inversely related to prostate cancer. Men who consumed soybean product more than twice per week on different days had a multivariate odds ratio （OR） of 0.38 （95% confidence interval [CI], 0.13-1.12）. In addition, men who consumed soybean products more than once per day had a multivariate OR of 0.29 （95% CI, 0.11-0.79） compared with men who consumed soybean products less than once per week. The P for trend was 0.02, which showed significant difference. There was no significant difference in P trend for any dairy food. Even when we matched the cases and controls by other criteria, we found that soybean food was the only preventive factor associated with prostate cancer. Conclusion： Our study suggests that consumption of soybeans, one of the most popular foods in Asia, would decrease the risk of prostate cancer.
基金the Key Research Program of Frontier Sciences,Chinese Academy of Sciences (No. QYZDB-SSW-DQC045)the National Natural Science Foundation of China (No. 41775116)。
文摘Depending on various government policies,COVID-19(Corona Virus Disease-19) lockdowns have had diverse impacts on global aerosol concentrations.In 2022,Changchun a provincial capital city in Northeast China,suffered a severe COVID-19 outbreak and implemented a very strict lockdown that lasted for nearly two months.Using ground-based polarization Light Detection and Ranging(LiDAR),we detected real-time aerosol profile parameters(EC,extinction coefficient;DR,depolarization ratio;AOD,aerosol optical depth),as well as air-quality and meteorological indexes from 1 March to 30 April in 2021 and 2022 to quantify the effects of lockdown on aerosol concentrations.The period in 2022 was divided into three stages:pre-lockdown(1-10 March),strict lockdown(11 March to 10 April),and partial lockdown(11-30 April).The results showed that,during the strict lockdown period,compared with the pre-lockdown period,there were substantial reductions in aerosol parameters(EC and AOD),and this was consistent with the concentrations of the atmospheric pollutants PM_(2.5)(particulate matter with an aerodynamic diameter ≤2.5 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter ≤10 μm),and the Oconcentration increased by 8.3%.During the strict lockdown,the values of EC within0-1 km and AOD decreased by 16.0% and 11.2%,respectively,as compared to the corresponding period in 2021.Lockdown reduced the conventional and organized emissions of air pollutants,and it clearly delayed the time of seasonal emissions from agricultural burning;however,it did not decrease the number of farmland fire points.Considering meteorological factors and eliminating the influence of wind-blown dust events,the results showed that reductions from conventional organized emission sources during the strict lockdown contributed to a 30% air-quality improvement and a 22% reduction in near-surface extinction(0-2 km).Aerosols produced by urban epidemic prevention and disinfection can also be identified using the EC.Regarding seasonal sources of agricultural straw burning,the concentrated burning induced by the epidemic led to the occurrence of heavy pollution from increased amounts of atmospheric aerosols,with a contribution rate of 62%.These results indicate that there is great potential to further improve air quality in the local area,and suggest that the comprehensive use of straw accompanied by reasonable planned burning is the best way to achieve this.
基金funded under the auspices of the National Key R&D Program of China(No.2017YFC0212303)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDB-SSW-DQC045)+3 种基金the National Natural Science Foundation of China(No.41775116)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2017275)Northeast Institute of Geography and Agroecology,CAS(No.IGA-135-05)Science and Technology Development Project in Jilin Province(No.20180520095JH)。
文摘Using a bottom-up estimation method,a comprehensive,high-resolution emission inventory of gaseous and particulate atmospheric pollutants for multiple anthropogenic sectors with typical local sources has been developed for the Harbin-Changchun city agglomeration(HCA).The annual emissions for CO,NO_(x),SO_(2),NH_(3),VOC S,PM_(2.5),PM 10,BC and OC during 2017 in the HCA were estimated to be 5.82 Tg,0.70 Tg,0.34 Tg,0.75 Tg,0.81 Tg,0.67 Tg,1.59 Tg,0.12 Tg and 0.26 Tg,respectively.For PM 10 and SO_(2),the emissions from industry processes were the dominant contributors representing 54.7%and 49.5%,respectively,of the total emissions,while 95.3%and 44.5%of the total NH_(3)and NO x emissions,respectively,were from or associated with agricultural activities and transportation.Spatiotemporal distributions showed that most emissions(except NH_(3))occurred in November to March and were concentrated in the central cities of Changchun and Harbin and the surrounding cities.Open burning of straw made an important contribution to PM_(2.5)in the central regions of the northeastern plain during autumn and spring,while domestic coal combustion for heating purposes was significant with respect to SO_(2)and PM_(2.5)emissions during autumn and winter.Furthermore,based on Principal Component Analysis and Multivariable Linear Regression model,air temperature,relative humidity,electricity and energy consumption,and the urban and rural population were optimized to be representative indicators for rapidly assessing the magnitude of regional atmospheric pollutants in the HCA.Such indicators and equations were demonstrated to be useful for local atmospheric environment management.
