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Effect of orchard age on soil nitrogen transformation in subtropical China and implications

Journal of Environmental sciences 2015年第8期27卷 10-19页

作者： Yushu Zhang Jinbo Zhang Tongbin Zhu Christoph Müller Zucong Cai school of Geography sciences Nanjing Normal University Institute of Soil and Fertilizer Fujian Academy of Agricultural Sciences jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control jiangsu center for collaborative innovation in geographical information resource development and application Key Laboratory of Virtual geographical Environment Ministry of Education Nanjing Normal University Department of Plant Ecology Justus-Liebig University Giessen

A better understanding of nitrogen transformation in soils could reveal the capacity for biological inorganic N supply and improve the efficiency of N fertilizers. In this study, a15 N tracing study was carried out to investigate the effects of converting woodland to orchard, and orchard age on the gross rates of N transformation occurring simultaneously in subtropical soils in Eastern China. The results showed that inorganic N supply rate was remained constant with soil organic C and N contents increased after converting woodland into citrus orchard and with increasing orchard age. This phenomenon was most probably due to the increase in the turnover time of recalcitrant organic-N, which increased with decreasing soil p H along with increasing orchard age significantly. The amo A gene copy numbers of both archaeal and bacterial were stimulated by orchard planting and increased with increasing orchard age. The nitrification capacity（defined as the ratio of gross rate of nitrification to total gross rate of mineralization） increased following the Michaelis–Menten equation, sharply in the first 10 years after woodland conversion to orchard, and increased continuously but much more slowly till 30 years. Due to the increase in nitrification capacity and unchanged NO3-consumption, the dominance of ammonium in inorganic N in woodland soil was shifted to nitrate dominance in orchard soils. These results indicated that the risk of NO3-loss was expected to increase and the amount of N needed from fertilizers for fruit growth did not change although soil organic N accumulated with orchard age.

关键词： 15N tracing technique Gross rates of nitrogen transformation Subtropical orchard soil

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Monitoring desertification processes in Mongolian Plateau using MODIS tasseled cap transformation and TGSI time series

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Journal of Arid Land 2018年第1期10卷 12-26页

作者： LIU Qingsheng LIU Gaohuan HUANG Chong State Key Laboratory of resources and Environmental information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100111China jiangsu center for collaborative innovation in geographical information resource development and application Nanjing 210023China

Most remote sensing studies assess the desertification using vegetation monitoring method. But it has the insufficient precision of vegetation monitoring for the limited vegetation cover of the desertification region. Therefore, it offers an alternative approach for the desertificafon research to assess sand dune and sandy land change using remote sensing in the desertification region. In this study, the indices derived from the well-known tasseled cap transformation （TCT）, tasseled cap angle （TCA）, disturbance index （DI）, process indicator （PI）, and topsoil grain size index （TGSI） were integrated to monitor and assess the desertification at the thirteen study sites including sand dunes and sandy lands distributed in the Mongolian Plateau （MP） from 2000 to 2015. A decision tree was used to classify the desertification on a regional scale. The average overall accuracy of 2000, 2005, 2010 and 2015 desertification classification was higher than 90%. Results from this study indicated that integration of the advantages of TCA, DI and TGSI could better assess the desertification. During the last 16 years, Badain Jaran Desert, Tengger Desert, and Ulan Buh Desert showed a relative stabilization. Otindag Sandy Land and the deserts of Khar Nuur, Ereen Nuur, Tsagan Nuur, Khongoryn Els, Hobq, and Mu Us showed a slow increasing of desertification, whereas Bayan Gobi, Horqin and Hulun Buir sandy lands showed a slow decreasing of desertification. Compared with the other 11 sites, the fine sand dunes occupied the majority of the Tengger Desert, and the coarse sandy land occupied the majority of the Horqin Sandy Land. Our findings on a three or four years＇ periodical fluctuated changes in the desertification may possibly reflect changing precipitation and soil moisture in the MR Further work to link the TCA, DI, TGSI, and PI values with the desertification characteristics is recommended to set the thresholds and improve the assessment accuracy with field investigation.

关键词： desertification MODIS desert sand dune sandy land Mongolian Plateau

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information geography: A new fulcrum of geographic ternary world

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Science China Earth sciences 2022年第2期65卷 383-386页

作者： Guonian LÜ Linwang YUAN Zhaoyuan YU Key Laboratory of Virtual Geographic Environment School of GeographyNanjing Normal UniversityMinistry of EducationNanjing 210023China jiangsu center for collaborative innovation in geographical information resource development and application Nanjing 210023China State Key Laboratory Cultivation Base of geographical Environment Evolution(jiangsu Province) Nanjing 210023China

The development trend of ternary space requires the construction of the information space for information mapping,transmission and transformation of geographic elements and social-human elements. Relevant researches of information geography from the perspective of Geographic information Science and human geography are reviewed in this paper, then the concept interpretation of information geography from the perspective of ternary space is proposed. It is presented in this paper that information geography can be constructed with a framework using seven geographic elements as the basic expressing dimensions and seven social-human elements as the basic aggregating core. information geography analyzes spatio-temporal distribution, structural characteristics, evolution process and interactions of various elements in the information space. And it eventually realizes the actual description, multi-scenario simulation, multi-objective decision-making and multi-channel control of the physical world and the social-human world.

关键词： information geography Ternary space Seven geographic elements Seven social-human elements

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Spatio-temporal distribution and transformation of cropland in geomorphologic regions of China during 1990–2015

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Journal of geographical sciences 2019年第2期29卷 180-196页

作者： GAO Xiaoyu CHENG Weiming WANG Nan LIU Qiangyi MA Ting CHEN Yinjun ZHOU Chenghu State Key Laboratory of resources and Environmental information System Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of sciences jiangsu center for collaborative innovation in geographical information resource development and application Institute of Agricultural resources and Regional Planning of CAAS

Landforms are an important factor determining the spatial pattern of cropland through allocation of surface water and heat. Therefore, it is of great importance to study the change in cropland distribution from the perspective of geomorphologic divisions. Based on China's multi-year land cover data(1990, 1995, 2000, 2005, 2010 and 2015) and geomorphologic regionalization data, we analyzed the change in cropland area and its distribution pattern in six geomorphologic regions of China over the period of 1990-2015 with the aid of GIS techniques. Our results showed that the total cropland area increased from 177.1 to 178.5 million ha with an average increase rate of 0.03%. Cropland area decreased in southern China and increased in northern China. Region I(Eastern hilly plains) had the highest cropland increase rate, while the cropland dynamic degree of Region IV(Northwestern middle and high mountains, basins and plateaus) was significantly higher than that of other regions. The barycenter of China's cropland shifted from northern China to the northwest over the 25-year period. Regions IV and I were the two regions with the greatest increase of cropland. Region II(Southeastern low and middle mountains) and Region V(Southwestern middle and low mountains, plateaus and basins) were the main decreasing cropland regions. The area of cropland remained almost unchanged in Region III(Northern China and Inner Mongolia eastern-central mountains and plateaus) and Region VI(Tibetan Plateau). The loss of cropland occurred mostly in Regions I and II as a result of growing industrialization and urbanization, while the increase of cropland occurred mainly in Region IV because of reclamation of grassland and other wasteland. These analyzing results would provide fundamental information for further studies of urban planning, ecosystem management, and natural resourcesconservation in China.

关键词： spatio-temporal distribution transformation of cropland geomorphologic regions China

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Effect of liming on sulfate transformation and sulfur gas emissions in degraded vegetable soil treated by reductive soil disinfestation

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Journal of Environmental sciences 2015年第10期27卷 112-120页

作者： Tianzhu Meng Tongbin Zhu Jinbo Zhang Zucong Cai school of Geography sciences Nanjing Normal University jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control jiangsu center for collaborative innovation in geographical information resource development and application Key Laboratory of Virtual Geographic Environment (VGE) Ministry of EducationNanjing Normal University jiangsu Key Laboratory of Environmental Change and Ecological Construction

Reductive soil disinfestation（RSD）, namely amending organic materials and mulching or flooding to create strong reductive status, has been widely applied to improve degraded ***, there is little information available about sulfate（SO4^2-） transformation and sulfur（S）gas emissions during RSD treatment to degraded vegetable soils, in which S is generally accumulated. To investigate the effects of liming on SO4^2-transformation and S gas emissions,two SO4^2--accumulated vegetable soils（denoted as S1 and S2） were treated by RSD, and RSD plus lime, denoted as RSD0 and RSD1, respectively. The results showed that RSD0 treatment reduced soil SO4^2-by 51% and 61% in S1 and S2, respectively. The disappeared SO4^2-was mainly transformed into the undissolved form. During RSD treatment, hydrogen sulfide（H2S）,carbonyl sulfide（COS）, and dimethyl sulfide（DMS） were detected, but the total S gas emission accounted for 〈 0.006% of total S in both soils. Compared to RSD0, lime addition stimulated the conversion of SO42-into undissolved form, reduced soil SO4^2-by 81% in S1 and 84% in S2 and reduced total S gas emissions by 32% in S1 and 57% in S2, respectively. In addition to H2S, COS and DMS, the emissions of carbon disulfide, methyl mercaptan, and dimethyl disulfide were also detected in RSD1 treatment. The results indicated that RSD was an effective method to remove SO4^2-, liming stimulates the conversion of dissolved SO4^2-into undissolved form,probably due to the precipitation with calcium.

关键词： Vegetable soil Reductive soil disinfestations Lime Sulfate Sulfur gases

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Land use transition and rural spatial governance: Mechanism, framework and perspectives

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Journal of geographical sciences 2020年第8期30卷 1325-1340页

作者： GE Dazhuan ZHOU Guipeng QIAO Weifeng YANG Mengqi school of Geography and Ocean Science Nanjing UniversityNanjing 210023China school of Geography Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationNanjing Normal UniversityNanjing 210023China Institute of Geographic sciences and Natural resources Research CASBeijing 100101China school of geographical sciences Guangzhou UniversityGuangzhou 510006China

The pattern for utilization of rural space is closely related to rural transformationdevelopment (RTD). The problem of rural space utilization is an important manifestation of theuncoordinated relationship between land use patterns and rural development status during atransformation period. Considering the rural space utilization issue, this article seeks to analyzethe interaction mechanisms between land use transition (LUT) and rural spatial governanceand then build a rural spatial governance analysis framework based on LUT. Also, thepaper explores the internal relationship between rural spatial governance and rural vitalizationand discusses the research prospective of the interaction. The study found that: (1) Ruralspace utilization has systemic problems such as limited development space, ill-defined ownershipand poor organization, which have become important obstacles for rural development.(2) The uncoordinated relationship between LUT and RTD is an important reason for the dilemmasurrounding rural space utilization. (3) The LUT provides a basis for determining thetiming of rural spatial governance, specifying spatial governance objectives, and clarifyingrural spatial governance methods. (4) The construction of a comprehensive analysis frameworkof “matter-ownership-organization” of rural space based on the LUT has created conditionsfor the orderly promotion of rural spatial governance. (5) Rural spatial governance whichfacilitates the integration of urban-rural development is an important foundation for rural vitalization.(6) Interaction analysis of LUT, RTD and rural spatial governance is conducive tofacilitating research on the operational mechanism of rural regional systems and to expandingthe research field of rural geography.

关键词： rural spatial governance land use transition rural vitalization urban-rural integrated development rural transformation development

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Topological relations between spherical spatial regions with holes

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International Journal of Digital Earth 2020年第4期13卷 429-456页

作者： Jingwei Shen Lan Zhang Min Chen Chongqing Engineering Research center for Remote Sensing Big Data application School of Geographical SciencesSouthwest UniversityChongqingPeople’s Republic of China Key Laboratory of Virtual Geographic Environment(Ministry of Education) Nanjing Normal UniversityNanjingPeople’s Republic of China jiangsu center for collaborative innovation in geographical information resource development and application NanjingJiangsuPeople’s Republic of China

There is growing interest in globally modelling the entire *** topological relations between spherical simple regions and topological relations between regions with holes in the plane have been investigated,few studies have focused on the topological relations between spherical spatial regions with *** 16-intersection model(16IM)is proposed to describe the topological relations between spatial regions with holes.A total of 25 negative conditions are proposed to eliminate the impossible topological relations between spherical spatial regions with *** results show that(1)3 disjoint relations,3 meet relations,66 overlap relations,7 cover relations,3 contain relations,1 equal relation,7 coveredBy relations,3 inside relations,1 attach relation,52 entwined relations,and 28 embrace relations can be distinguished by the 16IM and that(2)the formalisms of attach,entwined,and embrace relations between the spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on the simplified 16IM are different,whereas the formalisms of other types of relations between spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on a simplified 16IM are the same.

关键词： Topological relations spatial region with holes 16-intersection model(16IM) spatial analysis

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Numerical modeling and prediction of future response of permafrost to different climate change scenarios on the Qinghai-Tibet Plateau

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International Journal of Digital Earth 2016年第5期9卷 442-456页

作者： Wenjie Zhang Zhoupeng Ren Ling Yao Chenghu Zhou Yunqiang Zhu State Key Laboratory of resources and Environmental information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina University of Chinese Academy of sciences BeijingChina jiangsu center for collaborative innovation in geographical information resource development and application NanjingChina

Projecting the future distribution of permafrost under different climate change scenarios is essential,especially for the Qinghai–Tibet Plateau(QTP).The altitude-response model is used to estimate future permafrost changes on the QTP for the four RCPs(RCP2.6,RCP4.5,RCP6.0,and RCP8.5).The simulation results show the following:(1)from now until 2070,the permafrost will experience different degrees of significant degradation under the four RCP *** will affect 25.68%,40.54%,45.95%,and 62.84%of the current permafrost area,respectively.(2)The permafrost changes occur at different rates during the periods 2030–2050 and 2050–2070 for the four different RCPs.(1)In RCP2.6,the permafrost area decreases a little during the period 2030–2050 but shows a small increase from 2050 to 2070.(2)In RCP4.5,the rate of permafrost loss during the period 2030–2050(about 12.73%)is higher than between 2050 and 2070(about 8.33%).(3)In RCP6.0,the permafrost loss rate for the period 2030–2050(about 16.52%)is similar to that for 2050–2070(about 16.67%).(4)In RCP8.5,there is a significant discrepancy in the rate of permafrost decrease for the periods 2030–2050 and 2050–2070:the rate is only about 3.70%for the first period but about 29.49%during the second.

关键词： future permafrost changes Qinghai-Tibet Plateau altitude-response model temperature data VLRT RCPs

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Measuring time accessibility and its spatial characteristics in the urban areas of Beijing

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Journal of geographical sciences 2016年第12期26卷 1754-1768页

作者：王江浩邓羽宋辞田大江 Institute of Geographic sciences and Natural resources Research CAS jiangsu center for collaborative innovation in geographical information resource development and application The Postdoctoral Research Station of Tourism information Research center Beijing Union University & University of International Business and Economics school of information Technology and Management University of International Business and Economics

Construction of road infrastructure is fundamental to city operation and development, as well as an important pathway and focus in physical urban-rural integration. The long-term implementation of a system of ring roads plus radiating roads in Beijing has strongly impacted urban infrastructure construction and space-time accessibility. Particularly, recent rapid growth of private car ownership in Beijing has imposed greater loads on its road system, seriously hampering urban commuting efficiency and negatively impacting quality of life. To address such challenges and enhance the rapid development of transport infrastructure, Beijing has accelerated rail transit construction since 2008 in an effort to improve commuting capacity. This paper aims to measure time accessibility and its spatial characteristics in urban areas of Beijing by applying a comprehensive method that combines vector and raster attribute data generated from road network and subway transport infrastructure. By using a dual index of accessibility and road density, the study further reveals the features of and differences in spatial accessibility and the construction of road systems in urban areas of the northern and southern parts of Beijing. The findings of this study can provide a scientific basis for future urban planning and road system construction both in general and with respect to Beijing, given its aspirations to become a world city.

关键词： accessibility road density spatial characteristics Beijing

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Landslide Susceptibility Assessment of the Youfang Catchment using Logistic Regression

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Journal of Mountain Science 2015年第4期12卷 816-827页

作者： BAI Shi-biao LU Ping WANG Jian College of geographical sciences Key Laboratory of Virtual Geographic Environments (National Education Administration) Nanjing Normal University jiangsu center for collaborative innovation in geographical information resource development and application Nanjing Normal University jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing Normal University College of Surveying and Geo-Informatics Center for Spatial Information Science and Sustainable Development Applications Tongji University

A detailed landslide susceptibility map was produced in the Youfang catchment using logistic regression method with datasets developed for a geographic information system(GIS).Known as one of the most landslide-prone areas in China, the Youfang catchment of Longnan mountain region,which lies in the transitional area among QinghaiTibet Plateau, loess Plateau and Sichuan Basin, was selected as a representative case to evaluate the frequency and distribution of *** relationships for landslide susceptibility assessment were developed using landslide and landslide causative factor *** regression(LR)was used to create the landslide susceptibility maps based on a series of available data sources: landslide inventory; distance to drainage systems, faults and roads; slope angle and aspect; topographic elevation and topographical wetness index, and land *** quality of the landslide susceptibility map produced in this paper was validated and the result can be used fordesigning protective and mitigation measures against landslide *** landslide susceptibility map is expected to provide a fundamental tool for landslide hazards assessment and risk management in the Youfang catchment.

关键词： Landslide Susceptibility map Logistic regression Geographic information System(GIS) Youfang catchment

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