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Potential Role of Feldspathic Sandstone as a Natural Water Retaining Agent in Mu Us Sandy land,Northwest China

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Chinese Geographical Science 2012年第5期22卷 550-555页

作者： HAN Jichang XIE Jiancang ZHANG Yang Shaanxi Province Real Estate Development Corporation Xi' an 710075 China key laboratory of Degraded and Unused land consolidation Engineering the Ministry of Land and Resources of China Xi'an 710075 China Engineering Research Center for land consolidation of Shaanxi Province Xi'an 710075 China

This paper analyzed the water-retention mechanism of feldspathic sandstone （fine-（〈 1 mm diam.） and gravel-sized （2-3 cm diam.） in Mu Us Sandy land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on water retention in sandy land. The results showed that as the proportion of fine feldspathic sandstone in the sandy land soil increased, the soil texture changed from sand to silt loam, the capillary po- rosity gradually increased from 26.3% to 44.9%, and the soil saturated hydraulic conductivity decreased from 7.10 ram/rain to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy land soil, playing the role of a ＇water absorbent＇ and ＇water retaining agent＇ in sandy land. Amendment with feldspathic sandstone can increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land soil and increase soil water retention.

关键词： feldspathic sandstone sandy land soil water retaining agent Mu Us Sandy land soil saturatd hydraulicconductivity

Novel fuzzy uncertainty modeling for land cover classification based on clustering analysis

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Science China Earth Sciences 2019年第2期62卷 438-450页

作者： Hui HE Haihua XING Dan HU Xianchuan YU College of Information Technology Beijing Normal University Guangdong Province key laboratory for land Use and consolidation College of Information Science and Technology Beijing Normal University

It is well known that there is a degree of fuzzy uncertainty in land cover classification using remote sensing (RS) images. In this article, we propose a novel fuzzy uncertainty modeling algorithm for representing the features of land cover patterns, and present an adaptive interval type-2 fuzzy clustering method. The proposed fuzzy uncertainty modeling method is performed in two main phases. First, the segmentation units of the input multi-spectral RS image data are subjected to objectbased interval-valued symbolic modeling. As a result, features for each land cover type are represented in the form of an intervalvalued symbolic vector, which describes the intra-class uncertainty better than the source data and improves the separability between different classes. Second, interval type-2 fuzzy sets are generated for each cluster based on the distance metric of the interval-valued vectors. This step characterizes the inter-class high-order fuzzy uncertainty and improves the classification accuracy. To demonstrate the advantages and effectiveness of the proposed approach, extensive experiments are conducted on two multispectral RS image datasets from regions with complex land cover characteristics, and the results are compared with those given by well-known fuzzy and conventional clustering algorithms.

关键词： Interval-valued data Type-2 fuzzy sets Type reduction Type-2 fuzzy clustering land cover classification

Elevational distribution of forests and its spatiotemporal dynamics in subtropical China from 2000 to 2019

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Science China Earth Sciences 2024年第8期67卷 2563-2582页

作者： Zhencan ZHENG Liuwen ZHUANG Guofang MIAO Han LIU Zhiqiang CHENG Wenyu LI Rong SHANG Peng GONG Jing Ming CHEN Institute of Geography Fujian Normal University key laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education) Fujian Normal University School of Geographical Sciences Fujian Normal University National land consolidation Center Ministry of Natural Resources key laboratory of land consolidation and Rehabilitation Ministry of Natural Resources key laboratory of Digital Mapping and land Information Application Ministry of Natural Resources Department of Geography & Planning University of Toronto Department of Geography The University of Hong Kong

The subtropical region of China possesses abundant forest resources and features a mountainous *** the implementation of policies such as natural forest protection,the Grain for Green Project,and other initiatives since the beginning of the 21st century,coupled with climate change,the forest resources in this region have undergone significant changes compared to historical *** addition,forest resources distributing mainly in mountainous areas also implies that these changes may vary significantly with *** explore the spatiotemporal dynamics of forest distribution in subtropical China since 2000,especially the trend of changes with elevation,we analyzed the data from two land cover products focusing on forest cover and forest *** used a hierarchical approach,in which coarse-classification forest cover data with relatively small uncertainties impose constraints on forest type data with larger uncertainties,to achieve a reasonable balance between obtaining more details and reducing data *** first divided the forest cover data into‘unchanged'and‘changed'*** the constraints by the forest cover results,we further analyzed the‘unchanged'and‘changed'forest *** results indicated that,since the implementation of ecological engineering and management policies,54%of the area in the subtropical region had maintained unchanged forest cover attributes over the past 20 years,which implied the good state of ecological *** results also showed that dynamic conversions existed in the long term between forests and lands for essential production needs like *** elevational variations of forest cover suggested that the dominant changes came from the conversion between forests and croplands in low-elevation regions below 700 m,the conversion between forests and shrublands in mid-elevation regions of 700–1500 m,and the conversion between forests and grasslands in high-elevation regions above 2000 *** the regio

关键词： Subtropical China land cover Forest cover Forest type Elevational distribution

Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China

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Journal of Arid land 2024年第1期16卷 131-145页

作者： WANG Jing WEI Yulu PENG Biao LIU Siqi LI Jianfeng key laboratory of Degraded and Unused land consolidation Engineering Ministry of Natural and ResourcesXi'an 710075China Institute of land Engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi'an 710021China School of Human Settlements and Civil Engineering Xi'an Jiaotong UniversityXi'an 710049China Shaanxi key laboratory of land consolidation Xi'an 710064China

Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River ***,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)*** also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological *** results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,*** ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were *** GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more *** study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and e

关键词： ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model Loess Plateau

Forces Driving Changes in Cultivated land and Management Countermeasures in the Three Gorges Reservoir Area,China

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Journal of Mountain Science 2013年第1期10卷 149-162页

作者： CAO Yin-gui BAI Zhong-ke ZHOU Wei WANG Jing School of land Science and Technology China University of Geosciences key laboratory of land Reconsolidation and Rehabilitation Ministry of Land and Resources key laboratory of land Use Ministry of Land and Resources

The Three Gorges project accelerates economic development in the Three Gorges Reservoir *** paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces driving the changes in cultivated land area,and propose the countermeasures for cultivated land *** matrix was used to analyze the features of cultivated land changes,and quantitative analysis and qualitative analysis were adopted to research the driving forces according to the features of cultivated land *** land in the Three Gorges Reservoir Area mainly lay to the northwest of the Yangtze River,especially the upper *** areas of cultivated land increased from 1996 to 1999,then decreased from 2000 to 2006,and finally increased again from 2007 to *** important forces driving changes in cultivated land included government policies,employment and food security,increasing construction land,agriculture structure adjustment,land rearrangement,*** cultivated land management,firstly,it is necessary to insist on the principle of cultivated land protection,standardize land exploitation and strictly restrict the transformation of cultivated land into non-farming ***,land rearrangement must be implemented,which can not only increase the area of the cultivated land,but also improve the quality of the cultivated ***,it is feasible to intensify eco-agriculture construction to increase the quantity and quality of cultivated ***,it is helpful to improve the traditional agriculture production methods to promote cultivated land ***,it is important to propagandize cultivated land protection and realize the enormous pressure of cultivated land shortage,making more people obligated to protect cultivated land.

关键词： land use change Driving force Management countermeasure Cultivated land Three Gorges Reservoir Area

Influence of phosphate on deposition and detachment of TiO2 nanoparticles in soil

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Frontiers of Environmental Science & Engineering 2019年第5期13卷 163-173页

作者： Zhan Wang Chongyang Shen Yichun Du Yulong Zhang Baoguo Li Department of Soil and Water Sciences China Agricultural UniversityBeijing 100193China College of land and Environment Shenyang Agricultural UniversityShenyang 110866China key laboratory of Degraded and Unused land consolidation Engineering Ministry of Land and ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China

The widespread use of TiO2 nanoparticles (NPs) makes inevitable their release into the soil. Phosphate is also widespread within soil, and is likely copresent with TiO2 NPs. However, the influence of phosphate on deposition/release— and thereby on transport— of TiO2 NPs in soil is yet to be elucidated. In this study we conducted saturated column experiments to systematically examine the transport of TiO2 NPs in soil amended with phosphate at different ionic strengths (ISs) (1, 10, 100 mmol/L NaCl) and pHs (4 and 9). Results show that the deposition of TiO2 NPs decreased with decreasing IS, increasing pH, and when soil absorbed phosphate. These observations are qualitatively in agreement with Derjaguin-landau-Verwey-Overbeek (DLVO) interaction energy calculations, because the repulsive energy barrier is larger and secondary minimum depth is smaller at a lower IS, higher pH, and in the presence of phosphate. Accordingly, both primary- and secondary-minimum deposition were inhibited. Interestingly, although the deposition was less at higher pH and in the presence of phosphate, the subsequent spontaneous detachment and detachment by reduction of solution IS in these cases were greater. In addition, the presence of phosphate in the solution can cause a small quantity of attached TiO2 NPs to detach, even without perturbations of physical and chemical conditions. Our study was the first to investigate the influence of phosphate on detachment of TiO2 NPs and the results have important implication for accurate prediction of fate and transport of TiO2 NPs in subsurface environments.

关键词： Phosphate TiO2 nanoparticles Transport Soil Deposition Detachment

Variations and controlling factors of vegetation dynamics on the Qingzang Plateau of China over the recent 20 years

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Geography and Sustainability 2021年第1期2卷 74-85页

作者： Xiao Zhang Jun Wang Yan Gao Lixin Wang key laboratory of land consolidation and Rehabilitation Land Consolidation and Rehabilitation CenterMinistry of Natural ResourcesBeijing 100035China Department of Earth Sciences Indiana University–Purdue University Indianapolis(IUPUI)Indianapolis IN 46202USA

The impacts of climate change and human activities on vegetation dynamics have attracted wide attention,espe-cially in sensitive and vulnerable areas such as the Qingzang Plateau of *** this region,a series of ecological restoration projects have been launched while the effectiveness of these projects requires evaluation and further *** sensing with high temporal resolution and spatial coverage is an effective way for the vegetation dynamics research in this *** this study,the spatial and temporal distribution of climate factors and vegetation coverage as well as the influencing factors such as air temperature,precipitation,land use,slope,slope direction,soil and altitude were *** geographical detector was used to analyze the influence of climate factors on vegetation coverage and the interaction among factors in different eco-geographical *** results showed that:1)the average values from the 20 years of normalized difference vegetation index(NDVI)decreased gradually from southeast(>0.61)to northwest(0.12).The overall average of NDVI increased 0.02 per year from 1998 to 2018 and the impact factors varied among different eco-geographical regions;2)some con-trolling factors showed nonlinear enhancement such as altitude and slope;3)land use was an important factor affecting the distribution of vegetation especially in humid,semi-arid and arid areas,but the impacts of elevation and temperature were stronger than land use types in semi-humid and humid *** design and construc-tion of ecological protection and restoration projects on the Qingzang Plateau required scientific and detailed demonstration as well as monitoring and *** addition,new tools and theories were also needed in the selection of ecosystem restoration *** on the findings,this study also provides suggestions for the sustainable ecological restoration on the Qingzang Plateau.

关键词： Vegetation distribution Geo-detector Ecohydrology Ecological restoration Qingzang Plateau

Arrangement of High-standard Basic Farmland Construction Based on Village-region Cultivated land Quality Uniformity

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Chinese Geographical Science 2019年第2期29卷 325-340页

作者： SONG Wen WU Kening ZHAO Huafu ZHAO Rui LI Ting School of land Science and Technology China University of Geosciences key laboratory of land consolidation and Rehabilitation Ministry of Land and Resources

As an important constitute of land consolidation, high-standard basic farmland construction is an important means to protect the quantity, quality and ecological environment of cultivated land. Its target not only lies in the increase of cultivated land quantity, but also the improvement of cultivated land quality, agricultural production conditions and ecosystem environments. In the present study, the quality evaluation method and construction arrangement of cultivated land were explored to facilitate the process of decision-making and implementation for high-standard basic farmland construction(HSBFC) with administrative village as the unit. Taking the land comprehensive improvement project area in Quzhou County, Handan City, Hebei Province as a case study, the whole process of the study comprised of three steps: 1) establishment of the evaluation model of cultivated land quality uniformity based on regional optimum cultivated land quality, and construction of the uniformity evaluation index system from the aspects of soil fertility quality, engineering quality, spatial quality and eco-environment quality, according to the new concept of cultivated land quality; 2) calculation of cultivated land quality uniformity by grading indicators, assigning scores and weighting sums, exploring the local homogenization characteristics of regional cultivated land quality through spatial autocorrelation analysis, and analyzing the constraints and transformative potential of barrier factors; 3) arrangement of HSBFC according to the principle of concentration, continuity and priority to the easy operation. The results revealed that the value of farmland quality uniformity for the administrative villages in the study area was between 7.76 and 21.96, and there was a difference between various administrative villages. The regional spatial autocorrelation patterns included High-High(HH), Low-Low(LL), High-Low(HL) and Low-High(LH). These indicate that regional cultivated land quality

关键词： high-standard basic farmland cultivated land quality uniformity barrier factor arrangement

Bacterial community characteristics in epigeic and anecic earthworm vermicompartments within soil-earthworm systems

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Pedosphere 2024年第6期34卷 1038-1050页

作者： Zhiming SHI Shuyu SHI Wenwen LI Congying WANG Feng HU College of Environmental and Resource Sciences Shanxi University Soil Ecology laboratory College of Resources and Environmental SciencesNanjing Agricultural University Shanxi laboratory for Yellow River Shaanxi key laboratory of land consolidation School of Land EngineeringChang'an University

Earthworms are crucial to soil ecosystems as keystone species. They perform various ecological functions through their associated microbiomes. However,the characteristics of these microbiomes in various vermicompartments(earthworm-associated compartments) within soil-earthworm systems have not been systematically studied. Here, using earthworms of two ecotypes(i.e., epigeic Eisenia fetida and anecic Metaphire guillelmi) as models, we conducted a full and comprehensive exploration of the bacterial community in several potential distinct compartments, including bulk soil, drilosphere, gut wall,gut content, and casts, through 2D-terraria incubation technology and high-throughput sequencing approaches. Bacterial diversity, community structures in each compartment, differential OTUs in vermicompartments compared with bulk soil, and the co-occurrence relationship of bacteria in bulk soil and gut-compartments(i.e., gut wall and gut content) were assessed. Results showed that three major vermicompartments, i.e., drilosphere, gut, and casts, were distinctly different in hosting the bacterial community. The levels of alpha diversity followed the order of drilosphere > casts > gut wall ≈ gut content. These patterns of vermicompartments along earthworms did not vary with ecotype, implying that the vermicompartments were the primary factors influencing the bacterial community. Finally, based on the difference in microbiomes in gut-compartments and the state-of-the-art use of the term “gut microbiomes”, it is recommended to establish a unified definition of gut microbes that encompasses microbiomes residing in both the gut wall and gut content, which could provide a clear and consistent understanding of gut microbiomes. This work provides a comprehensive overview of earthworm-associated microbiomes,enhancing our understanding of fundamental earthworm ecology and soil biology.

关键词： bulk soil casts drilosphere ecotype gut microbiome gut-compartment