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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks China’s status
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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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The distribution patterns and temporal dynamics of carabid beetles(Coleoptera:Carabidae)in the forests of Jiaohe,Jilin Province,China
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作者 Shengdong Liu Shirui Dong +4 位作者 Ruitong Liu Qingfan Meng Yan Li Hongrui Zhao Yinghua Jin 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期333-342,共10页
Carabid beetles,predatory insects,are abundant in forests and sensitive to environmental changes.The distribution patterns and diversity of carabid beetles in several natural forests were studied to provide a basis fo... Carabid beetles,predatory insects,are abundant in forests and sensitive to environmental changes.The distribution patterns and diversity of carabid beetles in several natural forests were studied to provide a basis for evaluating the importance of a forest in the protection of carabid beetle diversity.Carabids were captured by pitfall traps during their seasonal activity from 2012 to 2013 in a poplar-birch forest,ash-walnut forest and broad-leaved Korean pine forest.A total of 5252 individuals,representing 21 species,were collected.Carabid abundance was highest in the broad-leaved Korean pine forest and lowest in the ash-walnut forest.Carabus billbergi Mannerheim and Pterostichus pertinax(Tschitscherine)were the dominant beetle species in each stand.Carabus canaliculatus Adams was dominant in the poplar-birch and ash-walnut forests,and Leistus niger Gebler was dominant in the ash-walnut forest.The carabids were affected differently by stand factors.C.billbergi and P.pertinax was positively correlated with mean DBH.C.canaliculatus and L.niger were not positively correlated with any stand factors.The broad-leaved Korean pine forest with greater age,large DBH and thick leaf litter fostered a high diversity of carabid species.The main yearly activity period for most carabids was during July.Different carabid species responded differently to seasonality,and the activity period of several species was relatively late(August)in the year. 展开更多
关键词 Carabid beetles Stand type Stand factors Temporal dynamics Distribution patterns Ordinal dates
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Erosion effects on soil microbial carbon use efficiency in the mollisol cropland in northeast China
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作者 Xuebing Zhang Guangting Pei +3 位作者 Tianyu Zhang Xianlei Fan Ziping Liu Edith Bai 《Soil Ecology Letters》 CSCD 2023年第4期51-63,共13页
●Soil erosion decreased soil microbial CUE and increased microbial uptake of carbon.●Soil erosion decreased microbial CUE by decreasing substrate C,N and MBC and increasing soil pH.●Soil microbes had to increase th... ●Soil erosion decreased soil microbial CUE and increased microbial uptake of carbon.●Soil erosion decreased microbial CUE by decreasing substrate C,N and MBC and increasing soil pH.●Soil microbes had to increase their uptake rate to cope with the loss of substrates with increasing erosion rate.●Soil microbial respiration increased with increasing degree of erosion.●Soil microbial growth rate remained relative stable under different degrees of soil erosion.●Microbial CUE in soil surface was less responsive to erosion than that in deeper soil.Soil microbial carbon use efficiency(CUE)is an important synthetic parameter of microbial community metabolism and is commonly used to quantify the partitioning of carbon(C)between microbial growth and respiration.However,it remains unclear how microbial CUE responds to different degrees of soil erosion in mollisol cropland.Therefore,we investigated the responses of soil erosion on microbial CUE,growth and respiration to different soil erosion rates in a mollisol cropland in northeast China based on a substrate independent method(18O-H2O labeling).Soils were sampled at four positions along a down-slope transect:summit,shoulder,back and foot.We found microbial CUE decreased significantly with increasing soil erosion rate in 5−20 cm soil,but did not change in 0−5 cm.The decrease of microbial CUE in subsoil was because microbes increased C uptake and allocated higher uptake C to microbial basal respiration with increasing soil erosion rate.Microbial respiration increased significantly with soil erosion rate,probably due to the more disturbance and unbalanced stoichiometry.Furthermore,soil microbes in surface soil were able to maintain their growth rates with increasing degree of erosion.Altogether,our results indicated that soil erosion could decrease microbial CUE by affecting soil physical and chemical properties,resulting in more decomposition of soil organic matter and more soil respiration,which had negative feedbacks to soil C sequestration and climate changes in cropland soil. 展开更多
关键词 soil organic carbon soil erosion microbial carbon use efficiency growth rate RESPIRATION
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Rare earth element geochemistry in soils along arid and semiarid grasslands in northern China
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作者 Yi‑Wen Cao Xiao‑Ming Liu +2 位作者 Chao Wang Edith Bai Nanping Wu 《Ecological Processes》 SCIE EI 2022年第1期386-399,共14页
Background:Rare earth elements(REE)are a group of trace elements that behave geochemically coherently.REE fractionation patterns normalized to reference materials provide a powerful tool for documenting pedogenesis.In... Background:Rare earth elements(REE)are a group of trace elements that behave geochemically coherently.REE fractionation patterns normalized to reference materials provide a powerful tool for documenting pedogenesis.Insoil processes are particularly difficult to illustrate with respect to contemporary and past climate conditions.In this study,we characterize the rare earth element(REE)contents in bulk soils and respective geochemical fractions(e.g.,exchangeable,carbonate‑bound,reducible,and oxidizable fractions)and to decipher the relationships between REE geochemistry components and climatic factors across a large‑scale northern China transect(NCT).Results:Across the NCT,bulk REE concentrations ranged from 55.2 to 241.1μg g^(−1)with a main portion in the residual fraction(49–79%),followed by oxidizable fraction(2–40%),reducible fraction(3–22%),carbonate‑bound fraction(0.1–16%),and negligible exchangeable fraction.The REE contents of geochemical components(carbonate‑bound,reducible,and oxidizable)in topsoils correlated to climate factors(mean annual precipitation,mean annual temperature,potential evaporation,and aridity index(AI)).The normalized abundances to the upper continental crust(UCC)composition show that the middle REE was generally enriched than the light REE and heavy REE in topsoils along the transect.The overall UCC‑normalized bulk REE patterns in topsoils and subsoils were similar,characterized by weak negative Ce anomalies and positive Eu anomalies.Conclusions:Our data in topsoils and depth profiles collectively suggest that cycling of REE was primarily regulated by abiotic processes in area with AI<0.2,while the biological effect on REE circulation in soil played a more effective role in area with AI>0.3.The similar UCC normalized patterns in topsoils suggest that the REE was originated from a common source with limited influences from other sources(e.g.,atmospheric dusts and anthropogenic contribu‑tions).Our results to some extent provide evidence for climatic influence REE distribution patterns both in topsoils and subsoils across the continental‑scale transect.Our investigation gives insights into future studies on vertical REE mobility and its associated biogeochemical pathways. 展开更多
关键词 Rare earth elements Soil GRASSLAND Northern China Aridity index
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