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Temporal and spatial variation and prediction of water yield and water conservation in the Bosten Lake Basin based on the PLUS-InVEST model
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作者 CHEN Jiazhen KASIMU Alimujiang +3 位作者 REHEMAN Rukeya WEI Bohao HAN Fuqiang ZHANG Yan 《Journal of Arid Land》 SCIE CSCD 2024年第6期852-874,共23页
To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research ... To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research was based on land use/land cover(LULC),natural,socioeconomic,and accessibility data,utilizing the Patch-level Land Use Simulation(PLUS)and Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)models to dynamically assess LULC change and associated variations in water yield and water conservation.The analyses included the evaluation of contribution indices of various land use types and the investigation of driving factors that influence water yield and water conservation.The results showed that the change of LULC in the Bosten Lake Basin from 2000 to 2020 showed a trend of increasing in cultivated land and construction land,and decreasing in grassland,forest,and unused land.The unused land of all the three predicted scenarios of 2030(S1,a natural development scenario;S2,an ecological protection scenario;and S3,a cultivated land protection scenario)showed a decreasing trend.The scenarios S1 and S3 showed a trend of decreasing in grassland and increasing in cultivated land;while the scenario S2 showed a trend of decreasing in cultivated land and increasing in grassland.The water yield of the Bosten Lake Basin exhibited an initial decline followed by a slight increase from 2000 to 2020.The areas with higher water yield values were primarily located in the northern section of the basin,which is characterized by higher altitude.Water conservation demonstrated a pattern of initial decrease followed by stabilization,with the northeastern region demonstrating higher water conservation values.In the projected LULC scenarios of 2030,the estimated water yield under scenarios S1 and S3 was marginally greater than that under scenario S2;while the level of water conservation across all three scenarios remained rather consistent.The results showed that Hejing County is an important water conservation function zone,and the eastern part of the Xiaoyouledusi Basin is particularly important and should be protected.The findings of this study offer a scientific foundation for advancing sustainable development in arid watersheds and facilitating efficient water resource management. 展开更多
关键词 PLUS model InVEST model Bosten Lake Basin water yield water conservation land-use simulation Geodetector
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The BEL1-like transcription factor GhBLH5-A05 participates in cotton response to drought stress
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作者 Jing-Bo Zhang Yao Wang +4 位作者 Shi-Peng Zhang Fan Cheng Yong Zheng Yang Li Xue-Bao Li 《The Crop Journal》 SCIE CSCD 2024年第1期177-187,共11页
Drought stress impairs crop growth and development.BEL1-like family transcription factors may be involved in plant response to drought stress,but little is known of the molecular mechanism by which these proteins regu... Drought stress impairs crop growth and development.BEL1-like family transcription factors may be involved in plant response to drought stress,but little is known of the molecular mechanism by which these proteins regulate plant response and defense to drought stress.Here we show that the BEL1-like transcription factor GhBLH5-A05 functions in cotton(Gossypium hirsutum)response and defense to drought stress.Expression of GhBLH5-A05 in cotton was induced by drought stress.Overexpression of GhBLH5-A05 in both Arabidopsis and cotton increased drought tolerance,whereas silencing GhBLH5-A05 in cotton resulted in elevated sensitivity to drought stress.GhBLH5-A05 binds to cis elements in the promoters of GhRD20-A09 and GhDREB2C-D05 to activate the expression of these genes.GhBLH5-A05 interacted with the KNOX transcription factor GhKNAT6-A03.Co-expression of GhBLH5-A05 and GhKNAT6-A03 increased the transcription of GhRD20-A09 and GhDREB2C-D05.We conclude that GhBLH5-A05 acts as a regulatory factor with GhKNAT6-A03 functioning in cotton response to drought stress by activating the expression of the drought-responsive genes GhRD20-A09 and GhDREB2C-D05. 展开更多
关键词 Cotton(Gossypium hirsutum) BEL1-like transcription factor Drought stress Transcriptional regulation Drought tolerance
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Distribution assessment of soil erosion with revised RUSLE model in Tianshan Mountains
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作者 WEI wenyu LIU Ya +1 位作者 ZHANG Lixia LI Lanhai 《Journal of Mountain Science》 SCIE CSCD 2024年第3期850-866,共17页
aSoil degradation caused by soil erosion is one of the world's most critical environmental issues.Soil erosion in the Tianshan Mountains has caused various environmental problems in the surrounding areas.This stud... aSoil degradation caused by soil erosion is one of the world's most critical environmental issues.Soil erosion in the Tianshan Mountains has caused various environmental problems in the surrounding areas.This study used remote sensing data to analyze the distribution of the factors influencing soil erosion,and the revised universal soil loss equation(RUSLE)to calculate the total amount and distribution characteristics of soil erosion in the Tianshan Mountains in 2019.Due to the large error of RUSLE in soil erosion estimation in mountainous areas,this study modified RUSLE equation based on the characteristics of snow cover in the Tianshan Mountains.The results show that the average soil erosion was 1690.3 t/(km^(2)·year),of which insignificant erosion,slight erosion and moderate erosion accounted for 42,8%,22.4%and 9.9%,respectively.Severe erosion and above accounted for 13.3%.The accuracy of the soil erosion modulus calculated by the RUSLE was only 61.9%,with an average error of 1631.9 t/(km^(2)·year).The average error of the double-coefficient correction method was 1259.1 t/(km^(2)·year),and the average error of the modified formula method was reduced by 40.3%compared with the RUSLE,reaching 973.7 t/(km^(2)·year),and its accuracy reached 76.2%.Very severe erosion and catastrophic erosion are distributed on mountain ridges with higher elevation and on the northern area with higher precipitation.Snow cover has a certain inhibitory effect on soil erosion,and snow cover in alpine mountains is a factor that cannot be ignored in soil erosion research. 展开更多
关键词 RUSLE Snow cover Erosion categories High-elevation area
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New indices to balanceα-diversity against tree size inequality
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作者 Li Zhang Brady K.Quinn +4 位作者 Cang Hui Meng Lian Johan Gielis Jie Gao Peijian Shi 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期229-237,共9页
The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large ... The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem functions.However,tree size inequality(TSI)has been largely neglected in studies using the available diversity indices.The TSI in the diameter at breast height(DBH)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size distribution.The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat.We also examined the relationships ofα-diversity indices with the GI using correlation tests.The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions,with most root-mean-square errors(990 out of 999 quadrats)being<0.0030.There were significant positive correlations between each of threeα-diversity indices(i.e.,R,D,and H’)and the GI.Nevertheless,the total abundance of trees in each quadrat did not significantly influence the GI.This means that the TSI increased with increasing spe-cies diversity.Thus,two new indices are proposed that can balanceα-diversity against the extent of TSI in the com-munity:(1−GI)×D,and(1−GI)×H’.These new indices were significantly correlated with the original D and H΄,and did not increase the extent of variation within each group of indices.This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change. 展开更多
关键词 Diameter at breast height(DBH) Gini index Shannon-Wiener index Simpson’s index QUADRAT Tree size
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Characteristics and drivers of the soil multifunctionality under different land use and land cover types in the drylands of China
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作者 SONG Boyi ZHANG Shihang +6 位作者 LU Yongxing GUO Hao GUO Xing WANG Mingming ZHANG Yuanming ZHOU Xiaobing ZHUANG Weiwei 《Regional Sustainability》 2024年第3期99-110,共12页
The drylands of China cover approximately 6.6×106 km2 and are home to approximately 5.8×10^(8)people,providing important ecosystem services for human survival and development.However,dryland ecosystems are e... The drylands of China cover approximately 6.6×106 km2 and are home to approximately 5.8×10^(8)people,providing important ecosystem services for human survival and development.However,dryland ecosystems are extremely fragile and sensitive to external environmental changes.Land use and land cover(LULC)changes significantly impact soil structure and function,thus affecting the soil multifunctionality(SMF).However,the effect of LULC changes on the SMF in the drylands of China has rarely been reported.In this study,we investigated the characteristics of the SMF changes based on soil data in the 1980s from the National Tibetan Plateau Data Center.We explored the drivers of the SMF changes under different LULC types(including forest,grassland,shrubland,and desert)and used structural equation modeling to explore the main driver of the SMF changes.The results showed that the SMF under the four LULC types decreased in the following descending order:forest,grassland,shrubland,and desert.The main driver of the SMF changes under different LULC types was mean annual temperature(MAT).In addition to MAT,pH in forest,soil moisture(SM)and soil biodiversity index in grassland,SM in shrubland,and aridity index in desert are crucial factors for the SMF changes.Therefore,the SMF in the drylands of China is regulated mainly by MAT and pH,and comprehensive assessments of the SMF in drylands need to be performed regarding LULC changes.The results are beneficial for evaluating the SMF among different LULC types and predicting the SMF under global climate change. 展开更多
关键词 Soil multifunctionality(SMF) Land use and land cover(LULC)changes Structural equation modeling(SEM) Climate change Dryland ecosystems
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Research on the Current Situation and Countermeasures of Integrating Artificial Intelligence into Ideological and Political Teaching in Universities
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作者 Siying Zhang 《Journal of Contemporary Educational Research》 2024年第5期15-20,共6页
With the rapid development of modern science and technology,artificial intelligence(AI)technology is becoming more and more mature,which has brought a profound impact on every field of human society.The new era backgr... With the rapid development of modern science and technology,artificial intelligence(AI)technology is becoming more and more mature,which has brought a profound impact on every field of human society.The new era background provides a new teaching concept for ideological and political teaching in colleges and universities.Teachers in colleges and universities should adopt a positive attitude to face the teaching change brought by new technology,update the teaching ideas in time,and adjust the teaching strategy.This paper will analyze the current situation of the integrated development of AI and ideological and political teaching and put forward corresponding teaching strategies to help train well-developed socialist successors. 展开更多
关键词 Artificial intelligence Ideological and political education Current situation analysis Countermeasure analysis
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A Comprehensive Study on Gender Language and Its Differences in China
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作者 Suofeiya Fan 《Journal of Contemporary Educational Research》 2024年第7期187-191,共5页
The study of language and gender,especially the study of gender language differences involves many fields such as psychology,sociology,anthropology,language and literature,news media,education,and so on.Starting from ... The study of language and gender,especially the study of gender language differences involves many fields such as psychology,sociology,anthropology,language and literature,news media,education,and so on.Starting from the broad definition of gender language,this paper composes and reviews the research history of domestic gender language and its differences.Around the research history of domestic gender language,the research period is divided according to the timeline into germination,genesis,and growth.Divided by theme and content,the main content is the phenomenon of sexism in language;the second is the study of gender language style differences;the third is the root causes of sexism and verbal gender differences,i.e.,the construction of the corresponding theories;and the fourth is the discussion of the limitations of the study of gender language in foreign countries. 展开更多
关键词 Language and gender Gender language differences Language differences
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Exploration of the “Four-Three-Four” Internship and Training Mode in Higher Vocational Colleges Under the Modern Vocational Education System
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作者 Jifeng Liu Na Han +2 位作者 Xiaojiao Li Jing Wang Xuezhen Feng 《Journal of Contemporary Educational Research》 2024年第3期111-117,共7页
This article mainly introduces the innovative internship and training model of vocational colleges,including five aspects such as“four-party collaboration,three-stage progression,four-way integration,value-added eval... This article mainly introduces the innovative internship and training model of vocational colleges,including five aspects such as“four-party collaboration,three-stage progression,four-way integration,value-added evaluation,and double selection and promotion.”The model aims to improve students’practical skills and professional quality to better adapt to market demand and social development.The article also presents the prospects of the future internship and training model,including strengthening cooperation and communication with industry enterprises,focusing on students’personalized development and practical skill cultivation,and establishing a scientific and objective evaluation and feedback mechanism. 展开更多
关键词 Four-party collaboration Three-stage progression Four-way integration Value-added evaluation Double selection and promotion
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Bio-geomorphologic features and growth process of Tamarix nabkhas in Hotan River Basin, Xinjiang 被引量:11
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作者 LI Zhizhong WU Shengli +3 位作者 CHEN Shujiang CHEN Xiuling JIN Jianhui LIU QI 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期205-218,共14页
Tamarix nabkha is one of the most widespread nabkhas, distributing in the arid region of China. Based on the observations outdoors and the simulation experiments in laboratories, analysis in this paper refers to the b... Tamarix nabkha is one of the most widespread nabkhas, distributing in the arid region of China. Based on the observations outdoors and the simulation experiments in laboratories, analysis in this paper refers to the biological geomorphologic features and growth process of Tamarix nabkhas in the middle and lower reaches of the Hotan River, Xinjiang. And the results indicate that the ecological type of Tamarix in the study area is a kind of Tugaic soil habitat based on the deep soil of the Populus Diversifolia forests and shrubs. This type of habitat can be divided into three kinds of sub-habitats which demonstrate the features of ecological environment of Tamarix nabkhas during the differential developed phases. Meanwhile, the Tamar, ix nabkha can exert intensified disturbance current on wind-sand flow on the ground,and its root and stems not only have strong potential of sprouting but are characteristic of wind erosion-tolerance, resistance to be buried by sand and respectively tough rigid of the lignified branches, for it has a rather longer life-time. Thus, the wind speed profile influenced by the Tamarix nabkha is different from the Phragmites nabkha and Alhagi nabkha. And the structure of the wind flow is beneficial to aeolian sand accumulating in/around Tamarix shrub, which can create unique Tamarix nabkhas with higher average gradient and longer periodicity of life. Tamarix nabkha evolution in the area experienced three stages: growth stage, mature and steady stage and withering stage. In each stage, morphological features and geomorphic process of Tamarix nabkha are different due to the discrep- ant interaction between the nabkha and aeolian sand flow. 展开更多
关键词 TAMARIX Nabkha biological geomorphology development mechanism Hotan River Basin XINJIANG
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Evaluation on Tourism Ecological Security in Nature Heritage Sites——Case of Kanas Nature Reserve of Xinjiang,China 被引量:13
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作者 LIU Xuling YANG Zhaoping +1 位作者 DI Feng CHEN Xuegang 《Chinese Geographical Science》 SCIE CSCD 2009年第3期265-273,共9页
The nature heritages are the precious legacy of nature with outstanding scientific and aesthetic value. They are quite different from other common ecotourism areas, because of its original and unique system, sensitive... The nature heritages are the precious legacy of nature with outstanding scientific and aesthetic value. They are quite different from other common ecotourism areas, because of its original and unique system, sensitive and vulnerable landscape, and peripheral cultural features. Therefore, the tourism development in the nature heritage sites should be on the premise of ecological security. The evaluation index system of tourism ecological security in nature heritage sites was constructed in this article by AHP and Delphi methods, including nature ecological security, landscape visual security and local culture ecological security, and the security thresholds of indices were also established. In the indices' weights of the evaluation model, the nature ecological security ranked the highest, followed by tourist landscape visual security and culture ecological security, which reflected the influence degree of the limited factor to tourism ecological security. Then, this paper carried out an empirical study of Kanas of Xinjiang Uygur Autonomous Region, China, which has the potential to be the World Nature Heritage. On the basis of the data attained from survey and observation on the spot, as well as questionnaire answered by tourists and local communities, the ecological security status in Kanas was evaluated. The result showed that the status of Kanas tourism ecological security was better, but there had some limiting factors. Lastly, effective measures were put forward to ensure its ecological security. 展开更多
关键词 nature heritage TOURISM ecological security nature ecological security landscape visual security local culture ecological security KANAS
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Vertical patterns in plant diversity and their relations with environmental factors on the southern slope of the Tianshan Mountains(middle section)in Xinjiang(China) 被引量:17
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作者 LIU Bin 《Journal of Mountain Science》 SCIE CSCD 2017年第4期742-757,共16页
The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation... The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation gradient in the middle section of the southern slope of the Tianshan Mountains in Xinjiang, China were explored, using the detrended canonical correspondence analysis (DCCA) and the generalized additive model (GAM) methods based on a field survey of 53 sampling plots. In this work 158 species of seed plants were recorded, including 141 herbaceous, 14 shrub, and 2 tree species, in which the woody plants are very limited. 53 sampling plots were classified into 9 major plant communities. The results indicate that the herb communities were the most sensitive to changes in elevation gradient. The diversity indices of the community as a whole presented bimodal patterns. The peak values for the species diversities were found in the transition region between mountain steppe desert and mountain desert steppe (2,200-2,300m), and in the alpine grassland region (2,900-3,100m), while maximum species diversities were in the areas of intermediate environmental gradient. The main environmental factors on the distribution patterns in plant diversity were the elevation, soft water, total nitroeen, available nitrogen, organic matter, and total salt. The response tendency of the four diversity indices for the whole community to the soil environment was the same as that of the herb layers. 展开更多
关键词 Species diversity Distribution pattern Plant community Soil properties Tianshan Mountains
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NORMAL FAMILIES OF MEROMORPHIC FUNCTIONS WITH SHARED VALUES 被引量:5
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作者 陈玮 田宏根 扈培础 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期87-93,共7页
We obtain some normality criteria of families of meromorphic functions sharing values related to Hayman conjecture, which improves some earlier related results.
关键词 meromorphic function shared value normal family
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Dynamic analysis and evaluation of Xinjiang forest resources:based on RS and GIS 被引量:4
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作者 LI Hu WANG Xiaofen +1 位作者 CHEN Shujiang HOU Ping 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期346-352,共7页
The forest resources in Xinjiang were surveyed and analyzed based on RS and GIS. Satellite data interpretation was adopted to obtain the general situation of Xinjiang forest resources in assistance with the sampling m... The forest resources in Xinjiang were surveyed and analyzed based on RS and GIS. Satellite data interpretation was adopted to obtain the general situation of Xinjiang forest resources in assistance with the sampling method and on-the-spot investigations. Based on GIS, related data obtained from satellite remote sensing in 1996 and 2001 were studied through contrastive analysis. Moreover, the dynamic variation of Xinjiang forest resources was studied in an all-around way. In the past five years, the areas of the forestland, woodland, sparse woodland, nursery garden and the land usable for forestry in Xinjiang kept growing, moreover, the forest cover rate and the total standing stock volume increased correspondingly, showing that the wooded area and the amount of growing stock in Xinjiang were increasing. The forestland area in Xinjiang went up to 17,837 km^2 from 17,331 km^2, with an annual average increase of 101 km^2. Accordingly, the forest vegetation came to 1.08% from 1.05%, up 0.03 percentage point; the total standing stock volume went up to 289,985,200 m^3 from 262,416,000 m^3, a total increase of 27,569,200 m^3, an annual average increase of 5,514,000 m^3 and an annual average net growth rate of 2.00%. The analysis results showed that the forest resources in Xinjiang were increasing on the whole, however, there remained some problems, such as the sparse natural forests, low forest cover rate, imbalanced wood age structure, and mono tree species composition, etc. 展开更多
关键词 XINJIANG forest resources development variety RS and GIS
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Interactions between water-land resources and oasis urban development at the northern slopes of the Tianshan Mountains,Xinjiang,China 被引量:9
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作者 Jun LEI Wen DONG +2 位作者 Yu YANG Jie LU Thomas STERR 《Journal of Arid Land》 SCIE 2012年第2期221-229,共9页
Urban development in arid and semi-arid regions is largely constrained by fragile physical environ- ments. The characteristics of an urban settlement are different from those in other regions of China. This paper anal... Urban development in arid and semi-arid regions is largely constrained by fragile physical environ- ments. The characteristics of an urban settlement are different from those in other regions of China. This paper analyses the coupling characteristics and spatio-temporal variations for oasis urban development and water-land resources at the northern slopes of the Tianshan Mountains by principal component analysis and a coupling degree model. The result shows that the degree and change in regional use of water and land resources are different among the studied cities/counties during their development. The built-up areas of these cities/counties have changed little with increasing populations and urbanization levels, which well reflects that the urban development in arid and semi-arid regions is limited by oasis areas. Per capita amount of water supplied, however, presented a trend of slowed growth with increasing levels of urbanization. Water consumption gradually increased with urban development and the improvement of people's living standards, accompanied by enhanced water use efficiency. The level of urbanization can be assessed through the coupling degree between oasis urban development and the use of water and land resources. A high coupling degree represents a high level of comprehensive urban devel- opment and use of water-land resources. Alternatively, a low coupling degree denotes a low level of urban devel- opment and water-land resource use. 展开更多
关键词 oasis urban development water-land resources coupling factors coupling degree northern slopes of the TianshanMountains
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Contamination and risk assessment of heavy metals in farmland soils of Baghrash County, Xinjiang, Northwest China 被引量:1
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作者 Ajigul Mamut Mamattursun Eziz +2 位作者 Anwar Mohammad Mattohti Anayit Atiyagul Rixit 《Research in Cold and Arid Regions》 CSCD 2017年第5期467-475,共9页
Soil pollution significantly reduces environmental quality.In this study,farmland soil samples were collected from 25 sites in Baghrash County,Northwest China;and the concentrations of eight heavy-metal elements(arsen... Soil pollution significantly reduces environmental quality.In this study,farmland soil samples were collected from 25 sites in Baghrash County,Northwest China;and the concentrations of eight heavy-metal elements(arsenic,As;cadmium,Cd;chromium,Cr;copper,Cu;manganese,Mn;nickel,Ni;lead,Pb;zinc,Zn)were determined by standard methods.The spatial distribution,contamination level,and ecological risk stature of heavy metals were analyzed based on GIS technology,the Geo-accumulation Index(Igeo),the Pollution Load Index(PLI),and the Potential Ecological Risk Index(RI).Results indicated that(1)The average concentrations of Cd exceeded 12.12 times the allowed national standard for soil environmental quality of China.The average concentrations of Cd,Cr,Ni,Pb,and Zn exceeded the background values of irrigation soils in Xinjiang by 60.58,1.25,1.50,4.95,and 5.10 times,respectively.(2)The pollution order of the average value of Igeo for heavy metals was ranked as Cd>Zn>Pb>Ni>Cr>Cu>As>Mn.The individual potential ecological risk index for heavy metals was ranked in the order of Cd>As>Ni>Cu>Pb>Cr>Zn.The average PLI for the study area showed a heavy pollution level,while the average RI showed a considerable ecological risk stature,as compared to the classification standard.(3)The spatial distribution patterns of eight heavy metal elements were substantially heterogeneous.The moderately polluted areas with moderate potential ecological risks were distributed in the southern parts of the study area,whereas the heavily polluted areas with considerable potential ecological risks were distributed in the northern parts.Overall,it was observed that Cd contributed most to the PLI and RI of the farmland soils in Baghrash County.The pollution risk of Cd should be a major concern,and human activities in the region should be cautious. 展开更多
关键词 FARMLAND soils HEAVY metal pollution ECOLOGICAL risk spatial distribution
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Normality Criteria of Meromorphic Functions Concerning Shared Analytic Function 被引量:1
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作者 YANG QI 《Communications in Mathematical Research》 CSCD 2016年第1期47-56,共10页
In this paper, we use Pang-Zalcman lemma to investigate the normal family of meromorphic functions concerning shared analytic function, which improves some earlier related results.
关键词 meromorphic function entire function shared function normal family
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Geostatistical analysis of variations in soil salinity in a typical irrigation area in Xinjiang, northwest China 被引量:1
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作者 Mamattursun Eziz Mihrigul Anwar XinGuo Li 《Research in Cold and Arid Regions》 CSCD 2016年第2期147-155,共9页
Characterizing spatial and temporal variability of soil salinity is tremendously important for a variety of agronomic and environmental concerns in arid irrigation areas. This paper reviews the characteristics and spa... Characterizing spatial and temporal variability of soil salinity is tremendously important for a variety of agronomic and environmental concerns in arid irrigation areas. This paper reviews the characteristics and spatial and temporal variations of soil salinization in the Ili River Irrigation Area by applying a geostatistical approach. Results showed that: (1) the soil salinity varied widely, with maximum value of 28.10 g/kg and minimum value of 0.10 g/kg, and was distributed mainly at the surface soil layer. Anions were mainly SO42- and Cl-, while cations were mainly Na+ and Ca2+; (2) the abundance of salinity of the root zone soil layer for different land use types was in the following order: grassland > cropland > forestland. The abundance of salinity of root zone soil layers for different periods was in the following order: March > June > September; (3) the spherical model was the most suitable variogram model to describe the salinity of the 0-3 cm and 3-20 cm soil layers in March and June, and the 3-20 cm soil layer in September, while the exponential model was the most suitable variogram model to describe the salinity of the 0-3 cm soil layer in September. Relatively strong spatial and temporal structure existed for soil salinity due to lower nugget effects; and (4) the maps of kriged soil salinity showed that higher soil salinity was distributed in the central parts of the study area and lower soil salinity was distributed in the marginal parts. Soil salinity tended to increase from the marginal parts to the central parts across the study area. Applying the kriging method is very helpful in detecting the problematic areas and is a good tool for soil resources management. Managing efforts on the appropriate use of soil and water resources in such areas is very important for sustainable agriculture, and more attention should be paid to these areas to prevent future problems. 展开更多
关键词 soil salinization VARIATION GEOSTATISTICS Ili River Irrigation Area
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Normality Criteria of Meromorphic Functions Concerning Shared Fixed-points 被引量:1
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作者 杨祺 《Chinese Quarterly Journal of Mathematics》 2015年第1期20-29,共10页
In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive intege... In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive integers. For every f ∈ F, all of whose zeros have multiplicity at least (nk+2)/(n-1). If f(f(k))nand g(g(k))nshare z in D for each pair of functions f and g, then F is normal. 展开更多
关键词 meromorphic function FIXED-POINTS shared value normal criterion
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Research on Coupling Relationship between Social Economy and Ecological Environment in Jinghe County of Aiby Lake Basin,Xinjiang 被引量:4
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作者 Lai Fengbing Sun Hu +1 位作者 Chen Shujiang Ren Shuang 《Meteorological and Environmental Research》 CAS 2014年第11期38-41,45,共5页
Based on the theory of sustainable development,using the theory and method of coupling relationship,the main city of Aiby Lake basin——Jinghe County in Xinjiang is selected. Based on the analyses of natural condition... Based on the theory of sustainable development,using the theory and method of coupling relationship,the main city of Aiby Lake basin——Jinghe County in Xinjiang is selected. Based on the analyses of natural condition,population growth,land use type and ecological environment,the comprehensive evaluation index systems of socio-economic development level and eco-environment quality in Jinghe County are constructed. Using principal component analysis,a comprehensive evaluation of socio-economic development level and ecological environment quality in Jinghe County is conducted by combining with Excel. Their coupling relationship is studied,and quantitative coordination degree between social economy and ecological environment in Jinghe County is obtained. The results show that in recent 50 years,socio-economic development level in Jinghe County is rising,but the ecological environment quality is falling. Their coupling degree C changes during [- 1. 260, + 0. 482],in other words,their coupling relationship is changing between " reluctant coordination" and " not coordination". After entering into the 21 stcentury,their coupling relationship is basically " reluctant coordination". On this basis,the existing problems in the process of sustainable development in Jinghe County are analyzed,and the suggestions about promoting coordinated development between social economy and ecological environment are put forward. 展开更多
关键词 Social economy Ecological environment Coupling relationship Jinghe County China
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A Note on Normal Families of Meromorphic Functions and Sharing Set 被引量:1
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作者 XIAO Bing WU Qi-feng YUAN Wen-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期360-365,共6页
In the paper,we prove the main result:Let k(≥2)be an integer,and a,b and c be three distinct complex numbers.Let F be a family of functions holomorphic in a domain D in complex plane,all of whose zeros have multiplic... In the paper,we prove the main result:Let k(≥2)be an integer,and a,b and c be three distinct complex numbers.Let F be a family of functions holomorphic in a domain D in complex plane,all of whose zeros have multiplicity at least k.Suppose that for each f∈F,f(z)and f(k)(z)share the set{a,b,c}.Then F is a normal family in D. 展开更多
关键词 entire function normal family meromorphic function share value set
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