In the context of global COVID-19 epidemic preparedness,the extensive use of disposable surgical masks(DSM)may lead to its emergence as a main new source of microplastics in the environment.Nowadays,DSMs have become a...In the context of global COVID-19 epidemic preparedness,the extensive use of disposable surgical masks(DSM)may lead to its emergence as a main new source of microplastics in the environment.Nowadays,DSMs have become a non-negligible source of plastic waste in aquatic environment,however,less research has been done on DSM after biofilm colonization in freshwater environment.The study investigated the microbial community of DSM-associated biofilms by 16S rRNA gene sequencing.Analysis of the microbial community in the middle and inner/outer layers of the DSM showed that the middle layer was different from the remaining two layers and that potential pathogens were enriched only in the middle layer of the DSM.Herein,we focused on the middle layer and explored the characterization properties and extracellular polymeric substances(EPS)components changes during biofilm formation.The results showed that the EPS components varied with the biofilm incubation time.As the formation of biofilm,the protein(PN)and polysaccharide(PS)in EPS showed an overall increasing trend,and the growth of PS was well synchronized with PN.Three fluorescent components of EPS were determined by the three-dimensional excitation emission matrix(3D-EEM),including humic acid-like,fulvic acid-like,and aromatic protein-like components.The percentage of fluorescent components varied with increasing biofilm development time and then stabilized.Fourier transform infrared spectroscopy(FTIR)characterization results elucidated the emergence of oxygen-containing functional groups during biofilm formation.Moreover,the hydrophilicity increased with biofilm development.In conclusion,the environmental behavior and ecological risks of DSM in aquatic environment deserve urgent attention in future studies.展开更多
Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs...Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs on the stability of these soils remain unclear.Here,we conducted freeze-thaw simulations in laboratory to investigate the effects of FTCs(0 to 15 cycles)on the wet-and dry-sieving aggregate stability of undisturbed sandy loam from Maqu county,which was treated with different initial soil moisture contents(1%to 25%in increments of 4%)and initial aggregate diameters(<2,2-5,5-10,and 10-15 mm).Results show that soil aggregates with initial diameters larger than 2 mm exhibit higher soil organic carbon contents(1.45%-1.57%)and silt contents(34.63%-35.52%)than those smaller than 2 mm(0.93%and 31.38%,respectively).The stability of both wet-and dry-sieving aggregates increases with larger initial diameters.Increasing initial soil moisture content from 1%to 25%reduces aggregate stability,with reductions of 2.4%-88.0%for wet-sieving aggregates and 2.1%-25.5%for dry-sieving aggregates(>2 mm).With increasing FTCs,wet-sieving aggregate(>2 mm)stability exhibits a fluctuating upward trend,with increases of 79.2%-87.4%after 15 FTCs,while dry-sieving aggregate(>2 mm)stability decreases significantly(5.7%-21.7%)upon the first FTC and remains unchanged thereafter.The stability of both the wet-and dry-sieving aggregates smaller than 2 mm remains unchanged with increasing FTCs(p>0.05).SOC content decreases by 22.3%on average with increasing FTCs from 1 to 15 and shows no significant correlations with wet-and dry-sieving aggregate stability.Higher silt content(r=0.39,p<0.05)and lower sand content(r=-0.38,p<0.05)enhances the wet-sieving aggregate stability of sandy loam.Frequent FTCs tend to improve wet-sieving aggregate stability but reduce dry-sieving aggregate stability in the sandy loam.The findings provide certain guidance for preventing freeze-thaw-induced wind erosion.展开更多
Based on the geochemical elements Rb and Sr in sediments with three different grain size fractions from profile H3 on the northern lacustrine bottomland 13 m above the Huangqihai Lake surface in 1986,the paper investi...Based on the geochemical elements Rb and Sr in sediments with three different grain size fractions from profile H3 on the northern lacustrine bottomland 13 m above the Huangqihai Lake surface in 1986,the paper investigates the record of palaeolake stand state, sedimentary environmental evolution,and winter monsoon change.First,these samples are separated into three different grain size fractions,i.e.,total sediments,77-20μm and〈20μm. Second,the chemical elements-Rb and Sr-of the grain size separation were tested and analyzed systematically in this paper.Then the elements compositions of these samples are measured using VP-320 mode fluorescence spectrum instrument,respectively.The magnetic susceptibility of these samples is measured using Kappabridge KLY-3 mode instrument made in Czech AGICO Company.The results showed the elements and the ratios varied regularly with the grain size.But the ratio of Rb/Sr in the sediments〈20μm correlates positively with the magnetic susceptibility of these samples.Therefore,the ratio of Rb/Sr in the fraction〈20 μm from the lake sediments reflected the strengthening of the weathering in the deposition sites.It is a good indicator of the summer monsoon-induced weathering and pedogenesis fluctuations and can be used to reconstruct the conditions of the paleoclimate and paleoenvironment.展开更多
Ice and snow chemistry of alpine glaciers is crucial for the research of regional atmospheric environment change. Fresh snow samples were weekly collected from Urumqi Glacier No.1 in the Tianshan Mountains, Xin- jiang...Ice and snow chemistry of alpine glaciers is crucial for the research of regional atmospheric environment change. Fresh snow samples were weekly collected from Urumqi Glacier No.1 in the Tianshan Mountains, Xin- jiang, China, and the chemical characteristics and seasonal variations of major ions, mineral dust, δ18O and trace metals were measured. Results show that the concentrations of major ions in the snow are Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+, in which Ca2+ is the dominant cation, and SO42-is the dominant anion. All major ions have close positive correlations with each other except NO3-. δ18O shows positive correlation with air temperature change during the study period. Mineral dust particle and major ionic concentrations in fresh snow have obvious seasonal change, with high concentration in spring but low concentration in summer and autumn, which indicates that the chemical mass input from Asian dust activity to snow is very significant. Temporal changes of trace metals in fresh snow, e.g., Cd, Pb, Zn, Al, Fe, have shown that human-induced pollution of central Asian region also has large contribution to the snow chemistry on alpine glaciers of the Tianshan Mountains.展开更多
The temporal-spatial geographic distribution of archaeological sites and its feature between 10.0-2.8 ka BP （ka BP= thousands of years before 0 BP, where ＂0 BP＂ is defined as the year AD 1950） were determined, bas...The temporal-spatial geographic distribution of archaeological sites and its feature between 10.0-2.8 ka BP （ka BP= thousands of years before 0 BP, where ＂0 BP＂ is defined as the year AD 1950） were determined, based on GIS spatial analysis in the Poyang Lake Basin. The relationship between geographic distribution of sites of different periods under subsis- tence existence of ancient civilizations, climate and environmental change was investigated. The results revealed numerous archaeological sites of the Neolithic Age （10.0-3.6 ka BP）. The sites were mainly located in the northern part of the Poyang Lake Basin, a hilly and mountainous area with many river terraces suitable for the development of human civilization. The number of archaeological sites rapidly increased during the Shang and Zhou dynasties （3.6-2.8 ka BP） and spread widely on the floodplains of the middle and lower reaches of Ganjiang River and onto the west, south, and southeast beach areas of the Poyang Lake. Holocene records of climate change suggested that it was possible that climate fluctuations had a great impact on human evolution in the study area. Before 3.6 ka BP, westward and northward expansion of Neolithic cultures in the Poyang Lake watershed occurred under the background of climate amelioration （becoming warmer and wetter）. The ancient people lived in the hilly areas with high elevation. The simple mode of a fishing and gathering economy was mostly suited to this area in the early Neolithic Age. The scope of human activities was expanded and cultural diversity developed in the late Neolithic Age. However, with population growth and increasing survival pressure in a dry-cold climatic stage after 3.6 ka BP, this sim-pie living mode had to be abandoned, and various forms of economy, the majority being ag- riculture, were developed on flood plains of the lower reaches of numerous rivers around Poyang Lake. This promoted flourishing of the Bronze culture of South China.展开更多
The dust deposits in the Yangtze River Basin(YRB)have been widely distributed along the Yangtze River valley.Previous studies mainly concentrated in its provenance of each loess site,however,the differences in provena...The dust deposits in the Yangtze River Basin(YRB)have been widely distributed along the Yangtze River valley.Previous studies mainly concentrated in its provenance of each loess site,however,the differences in provenance of loess among different sites in this area have rarely been studied.Here,the geochemical characteristics of the<20μm fraction in the loess in separate Jiujiang,Xuancheng and Nanjing sites were analyzed.The result shows that the loess in Jiujiang and Nanjing sites,near Yangtze River riverway,share similar geochemical characteristics that may commonly derived from the detrital materials of Yangtze River.However,both sites have significantly different elemental compositions compared with Xuancheng site,which is^60 km away from the Yangtze River riverway.These sites share different geochemical characteristics with Eastern Qinling Mountains and Xifeng section on the Chinese Loess Plateau,North China.Combining the distribution of the aeolian sand hills and the loess in this area published by previous studies,we suggest that the exposed river valley floodplain caused by weak summer monsoon provided abundant materials to form local dust cells controlled by strong winter monsoon during the glacial periods.Therefore,those local loess deposits should be identified as the“valley-sourced loess”.These reveal the inherent connection between the monsoon system and the loess deposits in Yangtze River Basin.展开更多
Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun ...Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun River source,Tian Shan,China,during July-September 2004 to 2007.We use correlation analysis,factor analysis and sea-salt tracing methods to examine the characteristics and sources of major ions and mineral dust particles in the snow.Results show that mineral dust particles and major ions in the snow pits vary seasonally.During the Asian dust period in springtime,the concentration of mineral dust particles and major ions deposited in snow is high,while the concentration is relatively low during the non-dust period of summer and autumn.This may be caused by dust storm activity in central Asia.The order of major ionic concentrations in the snow packs was determined to be Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+.Ca2+ was the dominant cation;SO42- was the dominant anion.We find,with the exception of NO3-,that the variabilities of ionic concentrations are highly correlated.Results show that the glacier region was significantly affected by dust activity and anthropogenic source.The major ions,especially Na+,originate from dust sources of central Asia and from the Ocean,transported by the westerly winds.展开更多
The climate paleogeography,especially the climate classifications,helps to interpret the global and regional climate changes and intuitively compare the climate conditions in different regions.However,the application ...The climate paleogeography,especially the climate classifications,helps to interpret the global and regional climate changes and intuitively compare the climate conditions in different regions.However,the application of climate classification in deep time(i.e.,climate paleogeography)is prohibited due to the usually qualitatively constrained paleoclimate and the inconsistent descriptions and semantic heterogeneity of the climate types.In this study,a climate paleogeography knowledge graph is established under the framework of the Deep-Time Digital Earth program(DDE).The hierarchical knowledge graph consists of five paleoclimate classifications based on various strategies.The classifications are described and their strengths and weaknesses are fully evaluated in four aspects:“simplicity,applicability,quantifiability,and comparability”.We also reconstruct the global climate distributions in the Late Cretaceous according to these classifications.The results are compared and the relationships among these climate types in different classifications are evaluated.Our study unifies scientific concepts from different paleoclimate classifications,which provides an important theoretical basis for the application of paleoclimate classifications in deep time.展开更多
Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in differen...Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in different depositional zones of Mahu Sag in the Junggar Basin,and to reconstruct their differential diagenetic evolutional processes.The diagenetic environment of shales in the lake-central zone kept alkaline,which mainly underwent the early stage(Ro<0.5%)dominated by the authigenesis of Na-carbonates and K-feldspar and the late stage(Ro>0.5%)dominated by the replacement of Na-carbonates by reedmergnerite.The shales from the marginal zone underwent a transition from weak alkaline to acidic diagenetic environments,with the early stage dominated by the authigenesis of Mg-bearing clay and silica and the late stage dominated by the dissolution of feldspar and carbonate minerals.The shales from the transitional zone also underwent a transition from an early alkaline diagenetic environment,evidenced by the formation of dolomite and zeolite,to a late acidic diagenetic environment,represented by the reedmergnerite replacement and silicification of feldspar and carbonate minerals.The differences in formation of authigenic minerals during early diagenetic stage determine the fracability of shales.The differences in dissolution of minerals during late diagenetic stage control the content of free shale oil.Dolomitic shale in the transitional zone and siltstone in the marginal zone have relatively high content of free shale oil and strong fracability,and are favorable“sweet spots”for shale oil exploitation and development.展开更多
Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typ...Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage 3a.Optically stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 ka.In addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and E.The average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,respectively.Analysis of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.展开更多
In this paper,we review the research progress in development geography since the 20th century,focusing on its connotation and theory,fields,methods,and development trends.Specifically,we systematically review the rese...In this paper,we review the research progress in development geography since the 20th century,focusing on its connotation and theory,fields,methods,and development trends.Specifically,we systematically review the research and applications of development geography,comprising fields such as the convergence of underdeveloped countries and regions,and the convergence of the process of improving the quality of life in developed countries and regions.Then,based on an analysis of research progress in development geography in foreign countries,we examine the development conditions and disciplinary advantages of development geography in China.Further,we highlight that future development geography research in China should focus on the latest international academic research and China’s national macro-strategic needs.Future research in development geography should be guided by the theory of sustainable development,the core of which is to improve sustainable livelihood capacity and regional green development levels in underdeveloped regions.This core includes the construction of industrial policy and development geography theory,as well as an interdisciplinary integrated research system.The focus must be placed on researching the spatial patterns,diffusion characteristics,and the convergence mechanism of regional development.Such a focus will facilitate exploration of the regulatory policies and scientific paths that serve regional economic construction and industrial development.展开更多
We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was a...We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was available by local biomass estimation models. In order to identify underlying mechanism of the species richness-biomass relationship, we included different water resource levels and number of individuals in each plot in our analysis. We sampled 15 and 20 plots （20 m ×20 m）, respectively, at both two sites. These plots were sampled equally on the sunny slope and the shady slope. Species richness, number of individuals of each species and diameter at breast height （DBH） as a substitute of biomass of tree layer were recorded in each sample. At one site, the relationship between species richness and biomass was significant on the sunny slope, and this relationship disappeared on the shady slope due to more environmental factors. The relations between species richness and number of individuals and between number of individuals and biomass paralleled the species richness-biomass relation on both slopes. The difference in number of individuals-biomass relationships on the sunny slope and the shady slope revealed ＂interspecific competitive exclusion＂ even though the species richness-biomass relationships were not hump-shaped. At the other site, species richness was not related to biomass or to number of individuals. Our study demonstrated the importance of environmental stress and succession of community in the understanding of species diversity-productivity patterns.展开更多
Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role...Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role in the harmonizing ecosystem, wetlands demand much attention as a significant part of our environment. Matasagar and Sukhsagar are very important historical wetlands of Bangladesh. But those are endangered today due to lack of public awareness of the dangers of their activities to the environment and unbridled profit making activities of the commercial users of the wetlands. Comparisons of maps and Google images from 1933 to present have shown that the forest areas of the wetlands have been progressively destroyed, and these have greatly affected the biodiversity of these areas mentioned. GIS (Geographic Information System) and remote sensing techniques are used to identify the changes in the aerial extent of those wetlands. This study also tried to explore present environmental conditions by in-situ observation. This is high time;some serious steps should be taken to ensure the conservation and preservation of these areas mentioned.展开更多
Electrical Conductivity Measurement （ECM） from ice core is a representative index for atmospheric environmental change. The pH value and ECM from three shallow ice cores （each 3.85 m, 231 ice samples total） on Gla...Electrical Conductivity Measurement （ECM） from ice core is a representative index for atmospheric environmental change. The pH value and ECM from three shallow ice cores （each 3.85 m, 231 ice samples total） on Glacier No.1 at the headwater of Urumqi River, Glacier No.48 in Kuitun area, and Miaoergou Glacier in Hami area in the eastern Tianshan Mountains, western China, were measured and analyzed for atmospheric environment records research. Ice core record shows that the changing trend of pH and ECM in three sites in recent years is different： ECM in Kuitun increases with the ice depth change, but ECM in Hami and Urumqi Glacier No.1 ice cores show a decreasing trend. Average ECM value in Hami is much larger than other two sites, just as the dust concentration and ions concentration are also very high in this site. ECM records in all three sites are mainly affected by aerosol mineral dust of Central Asia, and correlative coefficients of ECM and mineral ions such as Ca^2＋, Mg^2＋, Na^2＋ are all significantly high. The pH value and ECM are also significantly high correlative coefficients in the eastern Tianshan Mountains. Comparison between the eastern Tianshan Mountains and other sites in western China, and Polar Regions, shows that the difference of ECM can very well reflect the spatial difference of worldwide atmospheric environment.展开更多
During the 1992-1993 joint Australian-Chinese over-snow traverse of thewestern Lambert Glacier Basin (LGB), two firn cores were drilled respectively at MGA and LGB16.During the 1996-1997 and 1997-1998 austral summers,...During the 1992-1993 joint Australian-Chinese over-snow traverse of thewestern Lambert Glacier Basin (LGB), two firn cores were drilled respectively at MGA and LGB16.During the 1996-1997 and 1997-1998 austral summers, two firn cores were drilled respectively atDT001 and DT085 on the eastern LGB. Based on the measurements made during the expeditions, theclimatic and environmental features on both sides of the LGB have been studied. Results show thatduring the past 50 years, the trends of both air temperature and accumulation rate show a slightincrease on the east side of the LGB, in contrast to the west side of the LGB. The spatial trends ofthe accumulation rate measured by accumulation canes at 2 km intervals along the nearly 500 km ofthe traverse lines on both sides of the LGB are different. Moreover, correlations of δ^(18)O vsT_(10) along the two sides of the LGB are also different. In addition, the variations of sea saltion concentrations show different trends in the past 50 years. All the evidence shows that theLambert Glacier is a dividing region for the different climatic regimes over the East Antarctic icesheet, which may be due to different moisture resources resulting from special local circumfluencesuch as cyclone activities, local terrain influences.展开更多
[Objective] To reduce influences of adjustment of regional industrial structure on ecological environment,promote coordinated development of regional economy and ecological environment,and improve the relationship bet...[Objective] To reduce influences of adjustment of regional industrial structure on ecological environment,promote coordinated development of regional economy and ecological environment,and improve the relationship between human beings and natural environment. [Method]Based on the statistical data of Shaanxi Province during 1978- 2013,the ecological environmental impact index and effect index of industrial structure in Shaanxi Province were calculated,and then the ecological environment benefit of changes in industrial structure in Shaanxi Province from1978 to 2013 was assessed quantitatively. [Result]The impact of changes in industrial structure on ecological environment in Shaanxi Province was moderate,but later changes in industrial structure had greater influences on ecological environment than before. [Conclusion]Industrial structure in Shaanxi Province should be optimized further to ensure the healthy development of ecological environment.展开更多
Large-scale green tides in the Yellow Sea occurred for 13 consecutive years since 2007.The unusual co-occurrence of green tides and golden tides occurred in the Yellow Sea in 2017.The causative species are Ulva prolif...Large-scale green tides in the Yellow Sea occurred for 13 consecutive years since 2007.The unusual co-occurrence of green tides and golden tides occurred in the Yellow Sea in 2017.The causative species are Ulva prolifera and/or Sargassum horneri.Previous studies on physiological response characteristics of U.prolifera and S.horneri are done in the laboratory mainly,and there is no in-situ comparative study in this regard.In this study,the in-situ physiological response characteristics of both species were measured.The results indicated that cyclic electron flow and antioxidant system play more important roles in protecting U.prolifera,while non-photochemical quenching is more important for adapting to the environment in S.horneri.U.prolifera has a stronger ability to utilize nutrients to rapidly increase its biomass under a suitable condition compared to S.horneri.展开更多
Aerosol samples were collected at altitudes from 584 m a.s.l.to 3,804 m a.s.l.at seven sites of the eastern Tianshan.The occurrence,distribution,and possible sources of 47 trace metals—including alkali metals and alk...Aerosol samples were collected at altitudes from 584 m a.s.l.to 3,804 m a.s.l.at seven sites of the eastern Tianshan.The occurrence,distribution,and possible sources of 47 trace metals—including alkali metals and alkali earth metals,transition metals,lanthanoids,and heavy metals—were investigated.It was found that four sampling sites(Shuinichang,1,691 m a.s.l.;Urumqi City,809 m a.s.l.;Fu Kang Station,584 m a.s.l.;and Bogeda Glacier No.4,3,613 m a.s.l.)were contaminated mainly by heavy metals.Other three high-altitude sites(Urumqi Glacier No.1,3,804 m a.s.l.;Wang Feng road-maintenance station,3,039 m a.s.l.;and Tianshan Glaciology Station,2,135 m a.s.l.)were not polluted.The aerosol particles were clustered into two dominant types:crust-originated particles and pollution-derived particles.Aerosols from UG1,WF,and TGS were characterized by crust-originated particles such as clay,plagioclase,dolomite,alkali feldspar,and biotite;while those from SNC,Urumqi,FK,and BG4 were characterized by high content of Cl-rich particles,S-rich particles,and soot.The backward-trajectories results indicated that air masses arriving at SNC,Urumqi,FK,and BG4 were identified as the more polluted source,when compared to the short-range air mass transport from the North to UGI and WF.Relatively lower altitude,as well as terrain blocking,might be another important reason for the gradient difference in pollution influence among these seven places in the Urumqi River Basin.展开更多
“Earth summit mission 2022”is one of the landmark scientific research activities of the Second Tibetan Plateau Scientific Expedition and Research(STEP).This scientific expedition firstly used advanced technology and...“Earth summit mission 2022”is one of the landmark scientific research activities of the Second Tibetan Plateau Scientific Expedition and Research(STEP).This scientific expedition firstly used advanced technology and methods to detect vertical meteorological elements and produce forecasts for mountain climbing.The“Earth summit mission 2022”Qomolangma scientific expedition exceeded an altitude of over 8000 meters for the first time and carried out a comprehensive scientific investigation mission on the summit of Mt.Qomolangma.Among the participants,the westerly–monsoon synergy and influence team stationed in the Mt.Qomolangma region had two tasks:1)detecting the vertical structure of the atmosphere for parameters such as wind,temperature,humidity,and pressure with advanced instruments for high-altitude detection at the Mt.Qomolangma base camp;and 2)observing extreme weather processes to ensure that members of the mountaineering team could successfully reach the top.Through this scientific expedition,a better understanding of the vertical structure and weather characteristics of the complex area of Mt.Qomolangma is gained.展开更多
The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy developme...The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy development of ecological environment. With PRA survey method for obtaining questionnaire data and based on behavior geography and social psychology theory,farming-pastoral,dry grassland,desert grassland, typical project village alpine grassland of returning fazing land to grasslands as an example,with main body cognitive perspective of the aid of resources,the article analyzed space dissimilation of stakeholders environmental cognitive and behavior preference response in the area of returning grazing land to grasslands from ecological environment from policy environment,ecological environment and family economic environment aspects. The results showed that： stakeholders judgment of Grassland degradation in different ecological function area had obvious regularity,the cognitive proportion of Grassland degradation gradually increase from farming-pastora to alpine savanes. The satisfaction from returning grazing land to grasslands showed a changing tendency of reversed U. stakeholders had more strongly negative cognition in the area of dry steppe and desertsteppe. From farming-pastoral to alpine savanes,the economic environment tend to worse situation. Negative environmental behaviors tend to increase,Positive behavior on the contrary.展开更多
基金Supported by the Natural Science Foundation of Shandong Province(Nos.ZR2022MD115,ZR202111160067)。
文摘In the context of global COVID-19 epidemic preparedness,the extensive use of disposable surgical masks(DSM)may lead to its emergence as a main new source of microplastics in the environment.Nowadays,DSMs have become a non-negligible source of plastic waste in aquatic environment,however,less research has been done on DSM after biofilm colonization in freshwater environment.The study investigated the microbial community of DSM-associated biofilms by 16S rRNA gene sequencing.Analysis of the microbial community in the middle and inner/outer layers of the DSM showed that the middle layer was different from the remaining two layers and that potential pathogens were enriched only in the middle layer of the DSM.Herein,we focused on the middle layer and explored the characterization properties and extracellular polymeric substances(EPS)components changes during biofilm formation.The results showed that the EPS components varied with the biofilm incubation time.As the formation of biofilm,the protein(PN)and polysaccharide(PS)in EPS showed an overall increasing trend,and the growth of PS was well synchronized with PN.Three fluorescent components of EPS were determined by the three-dimensional excitation emission matrix(3D-EEM),including humic acid-like,fulvic acid-like,and aromatic protein-like components.The percentage of fluorescent components varied with increasing biofilm development time and then stabilized.Fourier transform infrared spectroscopy(FTIR)characterization results elucidated the emergence of oxygen-containing functional groups during biofilm formation.Moreover,the hydrophilicity increased with biofilm development.In conclusion,the environmental behavior and ecological risks of DSM in aquatic environment deserve urgent attention in future studies.
基金supported by National Natural Science Foundation of China(Grant No.42201080)Young Scientific and Technological Talents Program of Shaanxi Province(Grant No.2025ZC-KJXX-57)Special Scientific Research Program of the Shaanxi Provincial Department of Education(Grant No.21JK0967)。
文摘Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs on the stability of these soils remain unclear.Here,we conducted freeze-thaw simulations in laboratory to investigate the effects of FTCs(0 to 15 cycles)on the wet-and dry-sieving aggregate stability of undisturbed sandy loam from Maqu county,which was treated with different initial soil moisture contents(1%to 25%in increments of 4%)and initial aggregate diameters(<2,2-5,5-10,and 10-15 mm).Results show that soil aggregates with initial diameters larger than 2 mm exhibit higher soil organic carbon contents(1.45%-1.57%)and silt contents(34.63%-35.52%)than those smaller than 2 mm(0.93%and 31.38%,respectively).The stability of both wet-and dry-sieving aggregates increases with larger initial diameters.Increasing initial soil moisture content from 1%to 25%reduces aggregate stability,with reductions of 2.4%-88.0%for wet-sieving aggregates and 2.1%-25.5%for dry-sieving aggregates(>2 mm).With increasing FTCs,wet-sieving aggregate(>2 mm)stability exhibits a fluctuating upward trend,with increases of 79.2%-87.4%after 15 FTCs,while dry-sieving aggregate(>2 mm)stability decreases significantly(5.7%-21.7%)upon the first FTC and remains unchanged thereafter.The stability of both the wet-and dry-sieving aggregates smaller than 2 mm remains unchanged with increasing FTCs(p>0.05).SOC content decreases by 22.3%on average with increasing FTCs from 1 to 15 and shows no significant correlations with wet-and dry-sieving aggregate stability.Higher silt content(r=0.39,p<0.05)and lower sand content(r=-0.38,p<0.05)enhances the wet-sieving aggregate stability of sandy loam.Frequent FTCs tend to improve wet-sieving aggregate stability but reduce dry-sieving aggregate stability in the sandy loam.The findings provide certain guidance for preventing freeze-thaw-induced wind erosion.
基金National Natural Science Foundation of China, No.40401006
文摘Based on the geochemical elements Rb and Sr in sediments with three different grain size fractions from profile H3 on the northern lacustrine bottomland 13 m above the Huangqihai Lake surface in 1986,the paper investigates the record of palaeolake stand state, sedimentary environmental evolution,and winter monsoon change.First,these samples are separated into three different grain size fractions,i.e.,total sediments,77-20μm and〈20μm. Second,the chemical elements-Rb and Sr-of the grain size separation were tested and analyzed systematically in this paper.Then the elements compositions of these samples are measured using VP-320 mode fluorescence spectrum instrument,respectively.The magnetic susceptibility of these samples is measured using Kappabridge KLY-3 mode instrument made in Czech AGICO Company.The results showed the elements and the ratios varied regularly with the grain size.But the ratio of Rb/Sr in the sediments〈20μm correlates positively with the magnetic susceptibility of these samples.Therefore,the ratio of Rb/Sr in the fraction〈20 μm from the lake sediments reflected the strengthening of the weathering in the deposition sites.It is a good indicator of the summer monsoon-induced weathering and pedogenesis fluctuations and can be used to reconstruct the conditions of the paleoclimate and paleoenvironment.
基金Under the auspices of Major State Basic Research Development Program of China(No.2010CB951003)Knowledge Innovation Programs of the Chinese Academy of Sciences(No.KZCXZ-YW-127)National Natural Science Foundation of China(No.40631001,40571033,40701034,40371028,J0630966,40701035)
文摘Ice and snow chemistry of alpine glaciers is crucial for the research of regional atmospheric environment change. Fresh snow samples were weekly collected from Urumqi Glacier No.1 in the Tianshan Mountains, Xin- jiang, China, and the chemical characteristics and seasonal variations of major ions, mineral dust, δ18O and trace metals were measured. Results show that the concentrations of major ions in the snow are Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+, in which Ca2+ is the dominant cation, and SO42-is the dominant anion. All major ions have close positive correlations with each other except NO3-. δ18O shows positive correlation with air temperature change during the study period. Mineral dust particle and major ionic concentrations in fresh snow have obvious seasonal change, with high concentration in spring but low concentration in summer and autumn, which indicates that the chemical mass input from Asian dust activity to snow is very significant. Temporal changes of trace metals in fresh snow, e.g., Cd, Pb, Zn, Al, Fe, have shown that human-induced pollution of central Asian region also has large contribution to the snow chemistry on alpine glaciers of the Tianshan Mountains.
基金National Natural Science Foundation of China,No.41371204,No.41571179Major Program of the National Social Science Foundation of China,No.11&ZD183The Collaborative Innovation Center for Major Ecological Security Issues of Jiangxi Province and Monitoring Implementation,No.JXS-EW-00
文摘The temporal-spatial geographic distribution of archaeological sites and its feature between 10.0-2.8 ka BP （ka BP= thousands of years before 0 BP, where ＂0 BP＂ is defined as the year AD 1950） were determined, based on GIS spatial analysis in the Poyang Lake Basin. The relationship between geographic distribution of sites of different periods under subsis- tence existence of ancient civilizations, climate and environmental change was investigated. The results revealed numerous archaeological sites of the Neolithic Age （10.0-3.6 ka BP）. The sites were mainly located in the northern part of the Poyang Lake Basin, a hilly and mountainous area with many river terraces suitable for the development of human civilization. The number of archaeological sites rapidly increased during the Shang and Zhou dynasties （3.6-2.8 ka BP） and spread widely on the floodplains of the middle and lower reaches of Ganjiang River and onto the west, south, and southeast beach areas of the Poyang Lake. Holocene records of climate change suggested that it was possible that climate fluctuations had a great impact on human evolution in the study area. Before 3.6 ka BP, westward and northward expansion of Neolithic cultures in the Poyang Lake watershed occurred under the background of climate amelioration （becoming warmer and wetter）. The ancient people lived in the hilly areas with high elevation. The simple mode of a fishing and gathering economy was mostly suited to this area in the early Neolithic Age. The scope of human activities was expanded and cultural diversity developed in the late Neolithic Age. However, with population growth and increasing survival pressure in a dry-cold climatic stage after 3.6 ka BP, this sim-pie living mode had to be abandoned, and various forms of economy, the majority being ag- riculture, were developed on flood plains of the lower reaches of numerous rivers around Poyang Lake. This promoted flourishing of the Bronze culture of South China.
基金supported by the National Natural Science Foundation of China (No.41262007)the Collaborative Innovation Center for Major Ecological Security Issues of Jiangxi Province and Monitoring Implementation (No.JXS-EW-00)+2 种基金the Innovation Fund Designated for Graduate Students of Jiangxi Normal University(YJS2018069)the Foundation of Jiangxi Educational Committee (No.8884)the Opening Fund of Key Laboratory of Poyang Lake Wetland and Watershed Research(Jiangxi Normal University),Ministry of Education (PK2018004)
文摘The dust deposits in the Yangtze River Basin(YRB)have been widely distributed along the Yangtze River valley.Previous studies mainly concentrated in its provenance of each loess site,however,the differences in provenance of loess among different sites in this area have rarely been studied.Here,the geochemical characteristics of the<20μm fraction in the loess in separate Jiujiang,Xuancheng and Nanjing sites were analyzed.The result shows that the loess in Jiujiang and Nanjing sites,near Yangtze River riverway,share similar geochemical characteristics that may commonly derived from the detrital materials of Yangtze River.However,both sites have significantly different elemental compositions compared with Xuancheng site,which is^60 km away from the Yangtze River riverway.These sites share different geochemical characteristics with Eastern Qinling Mountains and Xifeng section on the Chinese Loess Plateau,North China.Combining the distribution of the aeolian sand hills and the loess in this area published by previous studies,we suggest that the exposed river valley floodplain caused by weak summer monsoon provided abundant materials to form local dust cells controlled by strong winter monsoon during the glacial periods.Therefore,those local loess deposits should be identified as the“valley-sourced loess”.These reveal the inherent connection between the monsoon system and the loess deposits in Yangtze River Basin.
基金supported by the National Basic Research Program (973) of China (Grant No.2010CB951003)Knowledge Innovation Programs of Chinese Academy of Science (Grant No.KZCXZ-YW-127)National Natural Science Foundation of China (Grant No. 91025012,40631001,40701034,40701035,1141001040)
文摘Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric environmental change.We examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun River source,Tian Shan,China,during July-September 2004 to 2007.We use correlation analysis,factor analysis and sea-salt tracing methods to examine the characteristics and sources of major ions and mineral dust particles in the snow.Results show that mineral dust particles and major ions in the snow pits vary seasonally.During the Asian dust period in springtime,the concentration of mineral dust particles and major ions deposited in snow is high,while the concentration is relatively low during the non-dust period of summer and autumn.This may be caused by dust storm activity in central Asia.The order of major ionic concentrations in the snow packs was determined to be Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+.Ca2+ was the dominant cation;SO42- was the dominant anion.We find,with the exception of NO3-,that the variabilities of ionic concentrations are highly correlated.Results show that the glacier region was significantly affected by dust activity and anthropogenic source.The major ions,especially Na+,originate from dust sources of central Asia and from the Ocean,transported by the westerly winds.
基金supported by the National Key R&D Plan of China(Grant No.2018YFE0204204)the National Natural Science Foundation of China(Grant Nos.42050104,41790455,and 42072116).
文摘The climate paleogeography,especially the climate classifications,helps to interpret the global and regional climate changes and intuitively compare the climate conditions in different regions.However,the application of climate classification in deep time(i.e.,climate paleogeography)is prohibited due to the usually qualitatively constrained paleoclimate and the inconsistent descriptions and semantic heterogeneity of the climate types.In this study,a climate paleogeography knowledge graph is established under the framework of the Deep-Time Digital Earth program(DDE).The hierarchical knowledge graph consists of five paleoclimate classifications based on various strategies.The classifications are described and their strengths and weaknesses are fully evaluated in four aspects:“simplicity,applicability,quantifiability,and comparability”.We also reconstruct the global climate distributions in the Late Cretaceous according to these classifications.The results are compared and the relationships among these climate types in different classifications are evaluated.Our study unifies scientific concepts from different paleoclimate classifications,which provides an important theoretical basis for the application of paleoclimate classifications in deep time.
基金Supported by the National Natural Science Foundation of China(42272117,42002116).
文摘Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in different depositional zones of Mahu Sag in the Junggar Basin,and to reconstruct their differential diagenetic evolutional processes.The diagenetic environment of shales in the lake-central zone kept alkaline,which mainly underwent the early stage(Ro<0.5%)dominated by the authigenesis of Na-carbonates and K-feldspar and the late stage(Ro>0.5%)dominated by the replacement of Na-carbonates by reedmergnerite.The shales from the marginal zone underwent a transition from weak alkaline to acidic diagenetic environments,with the early stage dominated by the authigenesis of Mg-bearing clay and silica and the late stage dominated by the dissolution of feldspar and carbonate minerals.The shales from the transitional zone also underwent a transition from an early alkaline diagenetic environment,evidenced by the formation of dolomite and zeolite,to a late acidic diagenetic environment,represented by the reedmergnerite replacement and silicification of feldspar and carbonate minerals.The differences in formation of authigenic minerals during early diagenetic stage determine the fracability of shales.The differences in dissolution of minerals during late diagenetic stage control the content of free shale oil.Dolomitic shale in the transitional zone and siltstone in the marginal zone have relatively high content of free shale oil and strong fracability,and are favorable“sweet spots”for shale oil exploitation and development.
基金the National Natural Science Foundation of China(Grant Nos.41472159,41172160,41371537).
文摘Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage 3a.Optically stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 ka.In addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and E.The average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,respectively.Analysis of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.
基金Key Program of National Natural Science Foundation of China,No.41771568。
文摘In this paper,we review the research progress in development geography since the 20th century,focusing on its connotation and theory,fields,methods,and development trends.Specifically,we systematically review the research and applications of development geography,comprising fields such as the convergence of underdeveloped countries and regions,and the convergence of the process of improving the quality of life in developed countries and regions.Then,based on an analysis of research progress in development geography in foreign countries,we examine the development conditions and disciplinary advantages of development geography in China.Further,we highlight that future development geography research in China should focus on the latest international academic research and China’s national macro-strategic needs.Future research in development geography should be guided by the theory of sustainable development,the core of which is to improve sustainable livelihood capacity and regional green development levels in underdeveloped regions.This core includes the construction of industrial policy and development geography theory,as well as an interdisciplinary integrated research system.The focus must be placed on researching the spatial patterns,diffusion characteristics,and the convergence mechanism of regional development.Such a focus will facilitate exploration of the regulatory policies and scientific paths that serve regional economic construction and industrial development.
基金the National Technology Support-ing Program of China (No. 2006BAD03A0206) for financial support.
文摘We analyzed the relationship between species richness and biomass in natural forest communities at two similar sites on Mt. Xiaolongshan, northwest China. At both sites, a wide range of tree layer biomass levels was available by local biomass estimation models. In order to identify underlying mechanism of the species richness-biomass relationship, we included different water resource levels and number of individuals in each plot in our analysis. We sampled 15 and 20 plots （20 m ×20 m）, respectively, at both two sites. These plots were sampled equally on the sunny slope and the shady slope. Species richness, number of individuals of each species and diameter at breast height （DBH） as a substitute of biomass of tree layer were recorded in each sample. At one site, the relationship between species richness and biomass was significant on the sunny slope, and this relationship disappeared on the shady slope due to more environmental factors. The relations between species richness and number of individuals and between number of individuals and biomass paralleled the species richness-biomass relation on both slopes. The difference in number of individuals-biomass relationships on the sunny slope and the shady slope revealed ＂interspecific competitive exclusion＂ even though the species richness-biomass relationships were not hump-shaped. At the other site, species richness was not related to biomass or to number of individuals. Our study demonstrated the importance of environmental stress and succession of community in the understanding of species diversity-productivity patterns.
文摘Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role in the harmonizing ecosystem, wetlands demand much attention as a significant part of our environment. Matasagar and Sukhsagar are very important historical wetlands of Bangladesh. But those are endangered today due to lack of public awareness of the dangers of their activities to the environment and unbridled profit making activities of the commercial users of the wetlands. Comparisons of maps and Google images from 1933 to present have shown that the forest areas of the wetlands have been progressively destroyed, and these have greatly affected the biodiversity of these areas mentioned. GIS (Geographic Information System) and remote sensing techniques are used to identify the changes in the aerial extent of those wetlands. This study also tried to explore present environmental conditions by in-situ observation. This is high time;some serious steps should be taken to ensure the conservation and preservation of these areas mentioned.
基金National Key Project for Basic Research of China,No.2007CB411501Knowledge Innovation Project of the Chinese Academy of Sciences, No.KZCX2-YW-127+7 种基金 National Natural Science Foundation of China,No.40631001 No.40571033 No.40701034 No.40701035 No.40371028 No.J0630966 The Project for Outstanding Young Scientists of National Natural Science Foundation of China,No.40121101The Fok Ying Tung Education Foundation,No.101019
文摘Electrical Conductivity Measurement （ECM） from ice core is a representative index for atmospheric environmental change. The pH value and ECM from three shallow ice cores （each 3.85 m, 231 ice samples total） on Glacier No.1 at the headwater of Urumqi River, Glacier No.48 in Kuitun area, and Miaoergou Glacier in Hami area in the eastern Tianshan Mountains, western China, were measured and analyzed for atmospheric environment records research. Ice core record shows that the changing trend of pH and ECM in three sites in recent years is different： ECM in Kuitun increases with the ice depth change, but ECM in Hami and Urumqi Glacier No.1 ice cores show a decreasing trend. Average ECM value in Hami is much larger than other two sites, just as the dust concentration and ions concentration are also very high in this site. ECM records in all three sites are mainly affected by aerosol mineral dust of Central Asia, and correlative coefficients of ECM and mineral ions such as Ca^2＋, Mg^2＋, Na^2＋ are all significantly high. The pH value and ECM are also significantly high correlative coefficients in the eastern Tianshan Mountains. Comparison between the eastern Tianshan Mountains and other sites in western China, and Polar Regions, shows that the difference of ECM can very well reflect the spatial difference of worldwide atmospheric environment.
基金The Key International Cooperation Project of Ministry of Science and Technology of China No.2001CB711003+3 种基金 National Natural Science Foundation of China No.40305007 The Science and Technology Innovation Project of Northwest Normal University No.NWNU-KJ
文摘During the 1992-1993 joint Australian-Chinese over-snow traverse of thewestern Lambert Glacier Basin (LGB), two firn cores were drilled respectively at MGA and LGB16.During the 1996-1997 and 1997-1998 austral summers, two firn cores were drilled respectively atDT001 and DT085 on the eastern LGB. Based on the measurements made during the expeditions, theclimatic and environmental features on both sides of the LGB have been studied. Results show thatduring the past 50 years, the trends of both air temperature and accumulation rate show a slightincrease on the east side of the LGB, in contrast to the west side of the LGB. The spatial trends ofthe accumulation rate measured by accumulation canes at 2 km intervals along the nearly 500 km ofthe traverse lines on both sides of the LGB are different. Moreover, correlations of δ^(18)O vsT_(10) along the two sides of the LGB are also different. In addition, the variations of sea saltion concentrations show different trends in the past 50 years. All the evidence shows that theLambert Glacier is a dividing region for the different climatic regimes over the East Antarctic icesheet, which may be due to different moisture resources resulting from special local circumfluencesuch as cyclone activities, local terrain influences.
基金Supported by the National Natural Science Foundation of China(41071359)Priority Research Project of Baoji University of Arts and Sciences(ZK12097)Planning Issues of Philosophy and Social Sciences in Baoji City(BISKGH2016-15)
文摘[Objective] To reduce influences of adjustment of regional industrial structure on ecological environment,promote coordinated development of regional economy and ecological environment,and improve the relationship between human beings and natural environment. [Method]Based on the statistical data of Shaanxi Province during 1978- 2013,the ecological environmental impact index and effect index of industrial structure in Shaanxi Province were calculated,and then the ecological environment benefit of changes in industrial structure in Shaanxi Province from1978 to 2013 was assessed quantitatively. [Result]The impact of changes in industrial structure on ecological environment in Shaanxi Province was moderate,but later changes in industrial structure had greater influences on ecological environment than before. [Conclusion]Industrial structure in Shaanxi Province should be optimized further to ensure the healthy development of ecological environment.
基金Supported by the National Key R&D Program of China(No.2016YFC1402102)the Key Laboratory of Marine Ecology and Environmental Science and Engineering,SOA(No.MESE-2019-02)+5 种基金the National Natural Science Foundation of China(Nos.41906120,41706121)the Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.JCZX202027)the Basic Applied Researching Projects of Qingdao(No.15-9-1-37-jch)the NSFC-Shandong Joint Fund(Nos.U1806213,U1606404)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDB-SSW-DQC023)the Fundamental Research Funds for the Central Universities(No.201964025)。
文摘Large-scale green tides in the Yellow Sea occurred for 13 consecutive years since 2007.The unusual co-occurrence of green tides and golden tides occurred in the Yellow Sea in 2017.The causative species are Ulva prolifera and/or Sargassum horneri.Previous studies on physiological response characteristics of U.prolifera and S.horneri are done in the laboratory mainly,and there is no in-situ comparative study in this regard.In this study,the in-situ physiological response characteristics of both species were measured.The results indicated that cyclic electron flow and antioxidant system play more important roles in protecting U.prolifera,while non-photochemical quenching is more important for adapting to the environment in S.horneri.U.prolifera has a stronger ability to utilize nutrients to rapidly increase its biomass under a suitable condition compared to S.horneri.
基金supported by the National Natural Science Foundation of China (41201065 41121001, 41261017, 41171057, 41161012)the Funds for Creative Research Groups of China (41121001)+3 种基金the foundation for Excellent Youth Scholars of CAREERI, CAS (51Y251B51)the SKLCS foundation (Grant No. SKLCSZZ-2012-01-01)the National Basic Research Program of China (2010CB951003, 2010CB951404)the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-EW-311)
文摘Aerosol samples were collected at altitudes from 584 m a.s.l.to 3,804 m a.s.l.at seven sites of the eastern Tianshan.The occurrence,distribution,and possible sources of 47 trace metals—including alkali metals and alkali earth metals,transition metals,lanthanoids,and heavy metals—were investigated.It was found that four sampling sites(Shuinichang,1,691 m a.s.l.;Urumqi City,809 m a.s.l.;Fu Kang Station,584 m a.s.l.;and Bogeda Glacier No.4,3,613 m a.s.l.)were contaminated mainly by heavy metals.Other three high-altitude sites(Urumqi Glacier No.1,3,804 m a.s.l.;Wang Feng road-maintenance station,3,039 m a.s.l.;and Tianshan Glaciology Station,2,135 m a.s.l.)were not polluted.The aerosol particles were clustered into two dominant types:crust-originated particles and pollution-derived particles.Aerosols from UG1,WF,and TGS were characterized by crust-originated particles such as clay,plagioclase,dolomite,alkali feldspar,and biotite;while those from SNC,Urumqi,FK,and BG4 were characterized by high content of Cl-rich particles,S-rich particles,and soot.The backward-trajectories results indicated that air masses arriving at SNC,Urumqi,FK,and BG4 were identified as the more polluted source,when compared to the short-range air mass transport from the North to UGI and WF.Relatively lower altitude,as well as terrain blocking,might be another important reason for the gradient difference in pollution influence among these seven places in the Urumqi River Basin.
基金funded by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2019QZKK0103)the Strategic Priority Research Program of Chinese Academy of Sciences(XDA20060101)the National Natural Science Foundation of China(Grant Nos.91837208,41830650).
文摘“Earth summit mission 2022”is one of the landmark scientific research activities of the Second Tibetan Plateau Scientific Expedition and Research(STEP).This scientific expedition firstly used advanced technology and methods to detect vertical meteorological elements and produce forecasts for mountain climbing.The“Earth summit mission 2022”Qomolangma scientific expedition exceeded an altitude of over 8000 meters for the first time and carried out a comprehensive scientific investigation mission on the summit of Mt.Qomolangma.Among the participants,the westerly–monsoon synergy and influence team stationed in the Mt.Qomolangma region had two tasks:1)detecting the vertical structure of the atmosphere for parameters such as wind,temperature,humidity,and pressure with advanced instruments for high-altitude detection at the Mt.Qomolangma base camp;and 2)observing extreme weather processes to ensure that members of the mountaineering team could successfully reach the top.Through this scientific expedition,a better understanding of the vertical structure and weather characteristics of the complex area of Mt.Qomolangma is gained.
基金Supported by the National Natural Science Fund(40971039)Gansu Province Science and Technology Support Program(1011FKCA157)the Fundamental Research Funds Project of Colleges and Universities in Gansu Province
文摘The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy development of ecological environment. With PRA survey method for obtaining questionnaire data and based on behavior geography and social psychology theory,farming-pastoral,dry grassland,desert grassland, typical project village alpine grassland of returning fazing land to grasslands as an example,with main body cognitive perspective of the aid of resources,the article analyzed space dissimilation of stakeholders environmental cognitive and behavior preference response in the area of returning grazing land to grasslands from ecological environment from policy environment,ecological environment and family economic environment aspects. The results showed that： stakeholders judgment of Grassland degradation in different ecological function area had obvious regularity,the cognitive proportion of Grassland degradation gradually increase from farming-pastora to alpine savanes. The satisfaction from returning grazing land to grasslands showed a changing tendency of reversed U. stakeholders had more strongly negative cognition in the area of dry steppe and desertsteppe. From farming-pastoral to alpine savanes,the economic environment tend to worse situation. Negative environmental behaviors tend to increase,Positive behavior on the contrary.
