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Spatiotemporal Differences and Classification Regulation of Urbanization Impact on Agricultural Development in Shrinking Areas:A Case Study of 15 Shrinking Cities in Three Provinces of Northeast China 被引量:1
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作者 CHEN Xiaohong LIU Haihan +4 位作者 AN Yongle DAI Yue PAN Wei WANG Ying TANG We 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1053-1067,共15页
Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shri... Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shrinking cities in the three provinces of Northeast China,this paper selects 15 shrinking cities as the research object,and constructs a multi-dimensional index system to explore the impact of the urbanization level of the shrinking areas on the agricultural development in the region since 2007–2019,analyzes the influencing factors and their differences by using the geographically-weighted regression model and Geodetector,and proposes a targeted regulation strategy.The results show that:1)overall,there is a negative correlation between the urbanization level and the agricultural development level in the contracted areas of the three northeastern provinces.The urbanization level in these areas has a certain negative impact on the overall level of agricultural development;2)regarding the time dimension,the impact of urbanization level on the agricultural development level in the contracted areas of the three northeastern provinces gradually increases over time;3)regarding the spatial pattern,the overall impact of shrinking urbanization levels in the three provinces of Northeast China on the agricultural development shows a significant distribution pattern of high in the east and low in the west;4)the total population and natural population growth rate at the end of the year were the main factors influencing a certain level of urbanization on agricultural development in the shrinking cities while population density and the urban fixed asset investment rate were the secondary factors;and 5)the main reasons why the level of agricultural development in different cities was affected by the level of urbanization were different.However,they can be categorized into areas of population loss and spatial construction,which can be further divided into area of population loss in the northeast,areas of negative population growth in the west,and areas of urban spatial change in the south.According to the causes of the impact,this paper adopted targeted regulation strategies and formulated relevant policies and solutions that cater to local conditions. 展开更多
关键词 URBANIZATION agricultural development classification and regulation shrinking cities three provinces of northeast china
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The Research on the Current Situation of English Interpreting Studies in Three Northeastern Provinces of China
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作者 刘璇 徐畔 《海外英语》 2015年第2期169-170,203,共3页
Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped int... Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped into a rapid development period in China as well as the research of interpreting studies. This paper aimed at providing a brief introduction of the current situation and existing problems of English interpreting studies in Three Northeastern Provinces of China under the comparative analysis of literature in CNKI China Academic Journal Network Publishing Database from 2004 to 2013. 展开更多
关键词 three northeastERN provinces of china ENGLISH INTERPRETING studies current SITUATION
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Time-lagged Effects of the Spring Atmospheric Heat Source over the Tibetan Plateau on Summer Precipitation in Northeast China during 1961–2020:Role of Soil Moisture 被引量:1
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作者 Yizhe HAN Dabang JIANG +2 位作者 Dong SI Yaoming MA Weiqiang MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1527-1538,共12页
The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in N... The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in Northeast China(NEC)remains unknown.The connection between spring TP AHS and subsequent summer precipitation over NEC from 1961 to 2020 is analyzed in this study.Results illustrate that stronger spring TP AHS can enhance subsequent summer NEC precipitation,and higher soil moisture in the Yellow River Valley-North China region(YRVNC)acts as a bridge.During spring,the strong TP AHS could strengthen the transportation of water vapor to East China and lead to excessive rainfall in the YRVNC.Thus,soil moisture increases,which regulates local thermal conditions by decreasing local surface skin temperature and sensible heat.Owing to the memory of soil moisture,the lower spring sensible heat over the YRVNC can last until mid-summer,decrease the land–sea thermal contrast,and weaken the southerly winds over the East Asia–western Pacific region and convective activities over the South China Sea and tropical western Pacific.This modulates the East Asia–Pacific teleconnection pattern,which leads to a cyclonic anomaly and excessive summer precipitation over NEC. 展开更多
关键词 Tibetan Plateau atmospheric heat source northeast china summer precipitation soil moisture
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An Analysis of Development Trend of Food Industry in Three Northeastern Provinces of China
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作者 Wenxin LIU Xiuli HE 《Asian Agricultural Research》 2018年第1期16-20,23,共6页
The food industry has developed into a leading industry in Northeast China.However,various economic indicators have shown a significant downward trend in recent years.Through the systematic analysis of the development... The food industry has developed into a leading industry in Northeast China.However,various economic indicators have shown a significant downward trend in recent years.Through the systematic analysis of the development trend of food industry in Northeast China in the past ten years,especially in 2014,it is found that in the context of stable and smooth operation of the food industry in China,the efficiency of the main processing industries declines in the three northeastern provinces of China,there is a simultaneous decline in the share of output value of the leading industries in the output value of manufacturing sector in three provinces,the collective and individual capital withdrawal is obvious in the paid-up capital,and there is a simultaneous decline in the industrial production and sales rate and the export delivery value.The food industry in Northeast China has plunged into the dilemma of development.Finally,this article puts forward some targeted recommendations from aspects of policy making,industrial agglomeration and enterprise cultivation. 展开更多
关键词 Food industry Agro-food processing industry Industrial production and sales rate Industrial agglomeration northeast china
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Climate and Soil Geochemistry Influence the Soil Organic Carbon Content in Drylands of the Songliao Plain,Northeast China
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作者 LIU Kai DAI Huimin +2 位作者 SONG Yunhong LIANG Shuai YANG Zhongfang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1394-1403,共10页
The understanding of the spatial distribution of soil organic carbon(SOC)and its influencing factors is crucial for comprehending the global carbon cycle.However,the impact of soil geochemical and climatic conditions ... The understanding of the spatial distribution of soil organic carbon(SOC)and its influencing factors is crucial for comprehending the global carbon cycle.However,the impact of soil geochemical and climatic conditions on SOC remains limited,particularly in dryland farming areas.In this study,we aimed to enhance the understanding of the factors influencing the distribution of SOC in the drylands of the Songliao Plain,Northeast China.A dataset comprising 35,188 measured soil samples was used to map the SOC distribution in the region.Multiple linear regression(MLR)and random forest models(RFM)were employed to assess the importance of driving indicators for SOC.We also carried out partial correlation and path analyses to further investigate the relationship between climate and geochemistry.The SOC content in dryland soils of the Songliao Plain ranged from 0.05%to 11.63%,with a mean value of 1.47%±0.90%.There was a notable increasing trend in SOC content from the southwest to the northeast regions.The results of MLR and RFM revealed that temperature was the most critical factor,demonstrating a significant negative correlation with SOC content.Additionally,iron oxide was the most important soil geochemical indicator affecting SOC variability.Our research further suggested that climate may exert an indirect influence on SOC concentrations through its effect on geochemical properties of soil.These insights highlight the importance of considering both the direct and indirect impact of climate in predicting the SOC under future climate change. 展开更多
关键词 soil organic carbon climate change soil geochemistry northeast china
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How Does Urban Shrinkage Affect Land Use Efficiency?A Case Study of Shrinking Cities in Northeast China
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作者 XIE Mingke FENG Zhangxian +2 位作者 SONG Yang GUAN Haoming WANG Shijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期34-51,共18页
The effect of urban shrinkage has gradually become a new topic.Theoretically,urban shrinkage may exert great influence on land use efficiency(LUE)through various urban subsystems,but there is currently limited researc... The effect of urban shrinkage has gradually become a new topic.Theoretically,urban shrinkage may exert great influence on land use efficiency(LUE)through various urban subsystems,but there is currently limited research examining these pathways.Using the Super-SBM-Undesirable model and the Structural Equation Model(SEM),this study calculates the LUE of shrinking cities in Northeast China and simulates the process of urban shrinkage affecting LUE.To quantify the process of urban shrinkage affecting LUE,three mediation variables,namely the economy,public services,and innovation,are used as latent variables to apply SEM.The results show that urban shrinkage will affect LUE through a direct path and indirect paths.In the direct path,urban shrinkage leads to an improvement in LUE.In the indirect paths,the economy and innovation will transmit the negative effect of urban shrinkage on LUE,while public services will reverse this effect.An important contribution of this study is that it quantifies the paths of urban shrinkage affecting LUE,thereby expanding the understanding of urban shrinkage effect and laying a foundation for the sustainable development of shrinking cities. 展开更多
关键词 urban shrinkage land use efficiency Super-SBM-Undesirable model Structural Equation Model(SEM) northeast china
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Contour Farming Suitability of the Black Soil Region in Northeast China and Its Spatial Characteristics
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作者 LI Yong ZHENG Shufeng +4 位作者 LIU Huanjun LUO Chong MENG Linghua WANG Yue WANG Liping 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1119-1133,共15页
Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique... Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique,it has not seen widespread implement-ation in China.Considering the deteriorating quality of arable lands in the Black Soil Region of Northeast China(BSR-NEC),it is ne-cessary to investigate spatial patterns and identify suitable areas for contour farming in this region.To achieve this objective,spatial autocorrelation and grouping analysis methods were employed to classify the land into four categories of suitability for contour farming:highly suitable,moderately suitable,generally suitable,and unsuitable.The results reveal that:1)the contour farming suitable area in BSR-NEC covers 89861.32 km^(2),accounting for 21.59%of arable land as of 2020.Heilongjiang Province owns the largest suitable area of 32853.68 km^(2),and Inner Mongolia has the highest proportion of 28.89%.2)In terms of the spatial distribution,regions with higher suitability for contour farming are concentrated in the Da Hinggan Mountains region,particularly Nenjiang City(Heilongjiang Province),which has the highest area of 2593.07 km^(2).Areas with a high proportion of suitable arable lands for contour farming are mainly found in the Da Hinggan Mountains and Changbai Mountains regions,with Ergun City(Inner Mongolia)having the highest pro-portion at 47.2%.Regions with higher suitability and proportion are concentrated in the Da Hinggan Mountains region,primarily cover-ing the Inner Mongolia and Heilongjiang.3)Regarding spatial clustering,both the area and proportion of suitable contour farming areas exhibit noticeable clustering effects,though not entirely consistent.4)Group analysis results designate 148 counties in BSR-NEC as highly suitable areas,predominantly located in the Changbai Mountains region,Liaodong Peninsula,Hulun Buir Plateau,and the north and south regions of the Da Hinggan Mountains.The zoning of suitable areas for contour farming in BSR-NEC informs the strategic de-velopment of policies and measures,allowing for the implementation of targeted policies in distinct areas suitable for contour farming.This provides a valuable reference for promoting contour farming technology more effectively and efficiently.re effectively and effi-ciently. 展开更多
关键词 contour farming spatial heterogeneity zoning policy spatial autocorrelation Black Soil Region of northeast china(BSR-NEC)
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Spatiotemporal dynamics of vegetation response to permafrost degradation in Northeast China
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作者 QIU Lisha SHAN Wei +3 位作者 GUO Ying ZHANG Chengcheng LIU Shuai YAN Aoxiang 《Journal of Arid Land》 SCIE CSCD 2024年第11期1562-1583,共22页
Permafrost in Northeast China is undergoing extensive and rapid degradation,and it is of great importance to understand the dynamics of vegetation response to permafrost degradation during different periods in this re... Permafrost in Northeast China is undergoing extensive and rapid degradation,and it is of great importance to understand the dynamics of vegetation response to permafrost degradation during different periods in this region.Based on the meteorological station data and MODIS land surface temperature data,we mapped the distribution of permafrost using the surface frost number(SFN)model to analyze the permafrost degradation processes in Northeast China from 1981 to 2020.We investigated the spatiotemporal variation characteristics of vegetation and its response to permafrost degradation during different periods from 1982 to 2020 using the normalized difference vegetation index(NDVI).We further discussed the dominant factors influencing the vegetation dynamics in the permafrost degradation processes.Results indicated that the permafrost area in Northeast China decreased significantly by 1.01×10^(5) km^(2) in the past 40 a.The permafrost stability continued to weaken,with large areas of stable permafrost(SP)converted to semi-stable permafrost(SSP)and unstable permafrost(UP)after 2000.From 1982 to 2020,NDVI exhibited a significant decreasing trend in the seasonal frost(SF)region,while it exhibited an increasing trend in the permafrost region.NDVI in the UP and SSP regions changed from a significant increasing trend before 2000 to a nonsignificant decreasing trend after 2000.In 78.63%of the permafrost region,there was a negative correlation between the SFN and NDVI from 1982 to 2020.In the SP and SSP regions,the correlation between the SFN and NDVI was predominantly negative,while in the UP region,it was predominantly positive.Temperature was the dominant factor influencing the NDVI variations in the permafrost region from 1982 to 2020,and the impact of precipitation on NDVI variations increased after 2000.The findings elucidate the complex dynamics of vegetation in the permafrost region of Northeast China and provide deeper insights into the response mechanisms of vegetation in cold regions to permafrost degradation induced by climate change. 展开更多
关键词 permafrost degradation surface frost number(SFN) normalized difference vegetation index(NDVI) vegetation response climate change northeast china
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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province china
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A three-dimentional model of the northeast East China Sea, with application to the M2 current field 被引量:1
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作者 Tang Yuxiang First Institute of Oceanography, State Oceanic Administration, Qingdao, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期487-498,共12页
A simple three-dimensional tidal model is used to examine the M2 tidal current distribution in a northeastern part of the East China Sea, especially the vertical variation of the current in the region. Computed M2 cur... A simple three-dimensional tidal model is used to examine the M2 tidal current distribution in a northeastern part of the East China Sea, especially the vertical variation of the current in the region. Computed M2 current is compared with observations available and found to be in good agreement.Main features of the calculating method in this study are: (1) Vertical variation of the tidal current is taken as a funetion of the depth-mean velocity: (2) the method is applicable to a variety of the vertical eddy viscosities; (3) it has a fine vertical resolution, especially near the sea bootom. So, this method not only enables us to get a steady state solution easily but also depicts effects of the friction on the vertical variation of the current much better. 展开更多
关键词 with application to the M2 current field A three-dimentional model of the northeast East china Sea
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Research Progress and Outlook of Low Temperature Chilling Injury in Northeast China 被引量:4
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作者 郝天依 王式功 +1 位作者 尚可政 李璟鑫 《Meteorological and Environmental Research》 CAS 2010年第11期85-91,96,共8页
Focused on the major agro-meteorological disaster in northeast China area—low temperature chilling injury,the research progresses of low temperature chilling injury in northeast China were reviewed systematically.The... Focused on the major agro-meteorological disaster in northeast China area—low temperature chilling injury,the research progresses of low temperature chilling injury in northeast China were reviewed systematically.The basic concepts which included the connotation and extension of chilling damage,the circulation characteristics and effect factors which formed summer low temperature in northeast China,the prediction,forecast and defense of low temperature chilling injury were summarized and done the outlook. 展开更多
关键词 northeast china low temperature chilling injury Circulation characteristics Effect factors PREDICTION DEFENSE china
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Fluorine Content in Soil and Groundwater of Songnen Plain in Northeast China 被引量:5
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作者 蔡贺 郭常来 +2 位作者 张梅桂 李旭光 张哲 《Agricultural Science & Technology》 CAS 2013年第2期376-383,共8页
[Objective] This study aimed to investigate the fluorosis content in the groundwater of Songnen Plain and provide a theoretical basis for the prevention and control of endemic fluorosis in Songnen Plain. [Method] The ... [Objective] This study aimed to investigate the fluorosis content in the groundwater of Songnen Plain and provide a theoretical basis for the prevention and control of endemic fluorosis in Songnen Plain. [Method] The relationship of drinking water type endemic fluorosis with the fluoride content in the soil and groundwater of Songnen Plain was analyzed. [Result] The endemic disease in this region is concentrated in the Song-Liao Plain and Hulunbuir Plateau on both sides of the Daxinganling Mountain. Severe and medium disease areas are distributed mainly in alluviallacustrine plains with dense depressions of lakes and marshes. The strata are commonly fine-grained loess and mucky soil. The groundwater is dominated by HCO3-Ca·Na and HCO3·Cl-Na·Ca types, with fluorine content of 1.80-16.00 mg/L, generally 4-6 mg/L. Light disease and non-disease areas are distributed in the alluvial-lacustrine plains with less or without depressions of lakes and marshes. The strata are mainly coarse-grained silty soil and sandy soil. The chemical types of ground water are Cl-Ca·Na and HCO 3 Cl-Na·Ca. The content of fluorine in ground water is commonly lower than 2 mg/L. [Conclusion] High fluorine groundwater formation is closely related to the geological environment. 展开更多
关键词 northeast china High-F water FLUOROSIS Geological environment
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Pollen Record of Surface Sediments from Vertical Forest Zones of Changbai Mountain, Northeast China and Their Relations to the Modern Vegetation 被引量:2
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作者 孙湘君 罗运利 +1 位作者 田军 吴玉书 《Acta Botanica Sinica》 CSCD 2003年第8期910-916,共7页
Twenty-nine surface samples (mosses) from five vertical distribution vegetation zones in Changbai Mountain, Northeast China have been palynologically analyzed and the results were tested by correspondence analysis. Th... Twenty-nine surface samples (mosses) from five vertical distribution vegetation zones in Changbai Mountain, Northeast China have been palynologically analyzed and the results were tested by correspondence analysis. The results show that, except a few samples, arboreal pollen is predominant in almost all pollen assemblages; Pinus and Betula are the main pollen types in quantities and they are found in all vegetation zones of Changbai Mountain. The highest pollen proportion of Pinus occurs in the mixed conifer and broadleaved forest where Pinus koraiensis is the main component; Betula pollen is found in high percentage in both subalpine B. ermanii forest and broadleaved deciduous forest predominated by Betula and Quercus; in the former Betula pollen is accompanied by cold-tolerant shrub such as Rhododendron; whereas in the latter it appears a large amount of fern spores. Pollen assemblage of broadleaved deciduous forests is marked by high diversity and proportions of deciduous trees and a large number of fern spores. Subalpine conifer forest is distinguished by high percentage of Picea pollen. Although tree pollen is slightly dominated, very few or absent of fern spores and increasing of herb and small shrub pollen proportions, particularly predominance of Rhododendron in herbaceous pollen and occurrence of tundra indicator type-Dryas pollen distinguish pollen assemblages of alpine tundra. 展开更多
关键词 Changbai mountain pollen of surface samples northeast china
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Diagnostic Analysis of Soil Moisture in Northeast China 被引量:2
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作者 李琛 沈新勇 李伟平 《Agricultural Science & Technology》 CAS 2010年第2期159-163,168,共6页
The horizontal distribution and vertical distribution characteristics of monthly average soil moisture(10-100 cm)of northeastern region of China in 22 years(1981-2002)were analyzed.The spatial and temporal variations ... The horizontal distribution and vertical distribution characteristics of monthly average soil moisture(10-100 cm)of northeastern region of China in 22 years(1981-2002)were analyzed.The spatial and temporal variations also were analyzed.The results showed that from 1981 to 2002,the northeast region surface(10-60 cm)of soil moisture show a downward trend,while the deep(60 cm)following an upward trend.The vertical structure of soil moisture of different years was different.Rainfall was one possible reason for ... 展开更多
关键词 northeast china Soil moisture Eof
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Temporal and Spatial Variation Characteristics of Precipitation during Crop Growing Season in Northeast China 被引量:2
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作者 李秀芬 李帅 +2 位作者 纪瑞鹏 郭春明 姜丽霞 《Agricultural Science & Technology》 CAS 2010年第6期137-140,168,共5页
[Objective] The aims were to understand variation characteristics of water resources and provide theoretical guidance for the formulation of agricultural irrigation methods.[Method] Taking the precipitation records du... [Objective] The aims were to understand variation characteristics of water resources and provide theoretical guidance for the formulation of agricultural irrigation methods.[Method] Taking the precipitation records during crop growing season(from April to September)observed by 177 weather stations from 1971 to 2008 in the three provinces of Northeast China(Heilongjiang,Jilin and Liaoning)as research data,annual change and spatial distribution characteristics of precipitation during crop growing season were analyzed by means of small grid interpolation and climatic trend rate.[Result] The precipitation during crop growing season general exhibited the decreasing trend and the precipitation trend rate was-8.6 mm/10a in Northeast China.In addition,there was lack of rain from 1971 to 1980 and relatively abundant of rain during 1981 and 1990 respectively.Moreover,the precipitation obviously exhibited decreasing trend from 1991 to 2008.But the decreasing trend was inconsistent in spatial distributions,that was,the precipitation slightly increased in relatively rainless areas and obviously decreased in relatively rainy areas.[Conclusion] The areas with obvious decreasing trend of precipitation during crop growing season are the main grain producing zones in Northeast China,so the problem of food production security caused by the precipitation changes should be paid enough attention. 展开更多
关键词 Regions in the northeast china Precipitation during crop growing season Temporal and spatial Variations
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Analysis on Status and Development Trend of Wind Erosion in Black Earth Region of Northeast China 被引量:2
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作者 刘铁军 珊丹 +2 位作者 郭建英 高天明 赵显波 《Agricultural Science & Technology》 CAS 2011年第12期1925-1928,共4页
In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In a... In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In addition,development trend of wind erosion in black earth region of Northeast China was analyzed from the aspects of the geographic position,climatic change law in recent 40 years and effects of northeast sand land desertification on wind erosion in black earth region,which had provided references for the research and prevention of wind erosion in soil of black earth region of Northeast China. 展开更多
关键词 Black earth region of northeast china Wind erosion Water loss and soil erosion Wind erosion factors
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Dynamic change of arborous species diversity in natural secondary forests after selective cutting on the north slope of Changbai Mountain, Northeast China
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作者 金永焕 周莉 +3 位作者 谷会岩 代力民 申光日 刘军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期299-302,共4页
The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration perio... The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration period of 28 years were studied. The results showed that the arborous species richness (S) had little change and kept the range of 18-22 all along, the Simpson index (D) of the secondary layer and regeneration layer and whole stand had similar trends of change, but that of the canopy layer descended slowly in initial 15 years and had little change later, and the change of diversity index was not obvious and the Shannon-Wiener index (H? fluctuated in a very small scopes (H±10%). 展开更多
关键词 Arborous species diversity Natural secondary forests Selective cutting northeast china
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Spatial connectivity and distribution of landscape type in the natural secondary forests of eastern mountainous region,northeast China——a case study of Mao'ershan region in Heilongjiang Province
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作者 李淑娟 隋玉正 +2 位作者 冯海清 王凤友 李玉文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期141-144,i003,共5页
Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculate... Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculated with ARC/INFO software for Mao'ershan region. The spatial distribution of the landscape of the region was analyzed. The results showed that the landscape connectivity index of non-woodland was significantly higher than that of woodland. The landscape connectivity index of natural forest was nearly equal to zero, which means its fragmentation degree is high. The nearest neighbor index of plantation was lower than that of natural forest and non-forestland. Among the man-made forests, the distance index of the coniferous mixed plantation is the lowest, and its pattern is nearly glomeration. The landscape pattern of natural forest presented nearly random distribution. Among non-forest land, the distance index of cut blank was the lowest, and its pattern was also nearly glomeration. Keywords Landscape type - Landscape pattern - Nearest neighbor index - Landscape connectivity index - Natural secondary forest - Northeast China CLC number S759.92 Document code A Foundation item: This paper was supported by the Key Project of State Department of Science Technology (2002BA515B040).Biography: LI SHu-juan (1977), female. Lecture in Ocean University of China, Qingdao 266003, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Landscape type Landscape pattern Nearest neighbor index Landscape connectivity index Natural secondary forest northeast china
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Factors Influencing Large-scale Operation of Large Grain Farmers in Northeast China
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作者 刘文新 何秀丽 《Agricultural Science & Technology》 CAS 2017年第12期2622-2627,2632,共7页
With the grain yield accounting for 20% of the whole country, the north- east China is a strategic region for ensuring national grain security and also a most centralized region of large grain farmers. Through a sampl... With the grain yield accounting for 20% of the whole country, the north- east China is a strategic region for ensuring national grain security and also a most centralized region of large grain farmers. Through a sampling survey of large grain farmers in 15 counties and cities of northeast China, with the aid of SPSS and AMOS software, using multiple regression analysis and structural equation modeling, this paper made a quantitative analysis on the influence of the subjective and ob- jective factors of large grain farmers on their large-scale management. The results showed that the age structure, educational level, family operating capital, yield ex- pectation and protective farming awareness of large grain farmers are the positive factors influencing their large scale operation due to agricultural subsidy policy. By comparison, the number of agricultural machinery and equipment owned by family, regional labor force, expectation for future income, and expectation for contractual scale become negative factors influencing large-scale operation of large grain farm- ers because of agricultural policies. When the future expectation, self conditions, family endowment, and operation conditions of large grain farmers increase one unit, their large scale operation motivation will increase by 0.692, 0.689, 0.487 and 0.363 units respectively. Thus, increasing the future expectation and self conditions of large grain farmers is a key factor for promoting large scale operation of farmland. 展开更多
关键词 Large grain farmers Large-scale operation Motivation northeast china
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Study on Relative Soil and Water Conservation Benefits of Ridge Tillage in Different Terrain Conditions in the Black Soil Area of Northeast China
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作者 赵玉明 姜洪涛 王世界 《Agricultural Science & Technology》 CAS 2015年第10期2354-2360,共7页
Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore... Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures. 展开更多
关键词 the black soil area in northeast china Ridge tillage Ridge direction Soil erosion Investigation of soil and water loss Soil and water conservation benefits
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