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Scale dependence of plant species richness and vegetation-environment relationship along a gradient of dune stabilization in Horqin Sandy Land, Northern China

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Journal of Arid Land 2014年第3期6卷 334-342页

作者： XiaoAn ZUO shaokun wang XueYong ZHAO Jie LIAN Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Laboratory of Stress Ecophysiology and Biotechnology Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Ecological patterns and processes in dune ecosystems have been a research focus in recent years, however the information on how dune stabilization influences the spatial scale dependence of plant diversity is still lacking. In this study, we measured the plant species richness, soil properties and altitude across four spatial scales （1, 10, 100 and 1,000 m2） at three different dune stabilization stages （mobile dune, semi-fixed dune and fixed dune） in Horqin Sandy Land, Northern China. We also examined the relationships between plant species richness, community composition and environmental factors along the gradient of dune stabilization. Our results showed that plant species richness increased with the increase of spatial scales in each dune stabilization stage, as well as with the increase of dune stabilization degrees. Canonical correspondence analysis （CCA） showed that plant distribu- tions in the processes of dune stabilization were determined by the combined environmental gradient in relation to soil organic carbon （SOC）, total nitrogen （TN）, carbon/nitrogen （C/N）, pH, electrical conductivity （EC）, soil water content （SWC）, fine sand （FS）, very fine sand （VFS）, silt and clay （SC）, and altitude. Plant species richness was significantly and positively correlated to SOC and TN in mobile dune, and significantly and positively correlated to SOC, TN, C/N, VFS and SC in semi-fixed dune. However, no significant correlation between plant species richness and environmental factors was observed in fixed dune. In addition, plant species richness in different dune stabili- zation stages was also determined by the combined gradient of soil properties and altitude. These results suggest that plant species richness has obvious scale dependence along the gradient of dune stabilization. Soil resources depending on dune habitats and environmental gradients caused by dune stabilization are important factors to de- termine the scale dependence of species diversity in sand dune eco

关键词： CCA environmental gradient sandy land ecosystem spatial scale dependence species diversity

Land cover changes and the effects of cultivation on soil properties in Shelihu wetland,Horqin Sandy Land,Northern China

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Journal of Arid Land 2013年第1期5卷 71-79页

作者： Jie LIANI XueYong ZHAO XiaoAn ZUO shaokun wang XinYuan wang YongQing LUO Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

Land cover change plays an essential role in the alternation of soils properties. By field investigation and applying satellite images, land cover information in the Shelihu wetland was carried out in an area of 2,819 hm2 in 1985, 1995, 2000, 2005, 2010 and 2011, respectively, in Horqin Sandy Land. A total of 57 soil sampling sites across Shelihu were chosen in wet meadow （CL0）, cropland （CL） and sandy land （SL） according to the spatial characteristics of water body change. Soil texture, organic carbon （SOC）, total nitrogen （TN） and total phosphorus （TP） contents, electrical conductivity （EC） and pH were measured at the soil depths of 0-10, 10-20 and 20-40 cm to examine the influence of agricultural conversion and continuous cultivation on soil properties. The results showed that the study area was covered by water body in 1985, which gradually declined afterwards and then reclaimed rapidly at a mean annual rate of 132.1 hm2/a from wet meadow to cropland since 1995. In 2011, water body was drained and the area was occupied by 10.8% of CL0, 76.9% of CL and 12.3% of SL. Large amounts of SOC, TN and TP were accumulated in the above depths in CL0. Soil in CL0 also had higher EC and silt and clay fractions, lower pH than in SL and CL. Soil in SL was seriously degraded with lower contents of SOC, TN and TP than in CL and CL0. SOC, TN content and EC in CL decreased with the increase of cultivation age, while pH showed a reverse trend with significance at plough horizon. The agricultural conversion in Shelihu was driven by the comprehensive factors of precipitation reduction, economic development and intense competitions for irrigation water. Continuous cultivation in this process is not sustainable because of SOC degradation and nutrient content reduction. The key point is that conventional tillage and removal of residuals induced further land degradation. Wetland reclamation for immediate economic interests led to greater costs in the long-term environmental restoration i

关键词： wetland soil degradation wetland reclamation continuous cultivation Horqin Sandy Land

Variation in soil water content to rainfall under Caragana microphylla shrub in Horqin Sandy Land

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Journal of Arid Land 2010年第3期2卷 174-179页

作者： wang, shaokun Zhao, XueYong Qu, Hao Luo, YaYong Yun, JianYing Chinese Acad Sci Naiman Desertificat Res Stn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

In order to investigate the spatio-temporal variability of soil water content to rainfall under Caragana microphylla shrub in Horqin Sandy Land,a plot of 25 m × 25 m,where there were 6 shrub canopies of C. microphylla,was sited for measuring soil water content at two soil layers of 0-20 cm (top layer) and 20-40 cm (lower layer). Soil water content was measured on the 1st,5th,10th and 15th day after a 42 mm rainfall in Naiman of Inner Mongolia. The results showed that soil water contents at both layers under C. microphylla shrub were gradually decreased after the rain. Soil water content at the top layer outside the shrub canopy was higher than that inside the shrub canopy within 5 days,and became similar inside and outside the shrub canopy on the 10th day after the 42 mm rainfall,and it was lower outside than that inside the shrub canopy on the 15th day. The soil water content at lower layer in the area without shrubs was higher than that under shrub canopy all along. All the measured values of soil water content can be fitted to a variogram model. There was significant autocorrelation of the values of soil water content between top layer and lower layer,except for the fourth measured values of soil water content at top layer. The range and spatial dependence of soil water content at top layer were lower than that at lower layer.

关键词： Horqin Sandy Land Caragana microphylla soil water content spatial variability

Impact of sand burial on maize(Zea mays L.)productivity and soil quality in Horqin sandy cropland,Inner Mongolia,China

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Journal of Arid Land 2016年第4期8卷 569-578页

作者： wang shaokun ZHAO Xueyong ZHAO Halin LIAN Jie LUO Yongqing YUN Jianying Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Laboratory of Stress Ecophysiology and Biotechnology Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Croplands are often suffering from sand burial in dry regions of northern China. For studying this phenomenon, we carried out a case study of field experiment including four sand burial levels, i.e. shallow （1-3 cm）, moderate （8-12 cm） and deep （15-20 cm） sand burials, and no sand burial （control, CK）, in a typical agro-pastoral transitional zone in Naiman Banner of eastern Inner Mongolia. The aim of this study was to assess the impacts of sand burial on maize （Zea rnays L.） productivity and the soil quality along a gradient of burial depths. Results showed that there was a strong negative effect of sand burial on maize productivity and soil quality, which significantly declined （P〈0.05） under moderate and deep sand burial treatments. In comparison with the CK, the maize yield and above-ground biomass reduced by 47.41% and 39.47%, respectively. The soil silt and clay, soil water, soil organic carbon and total nitrogen contents under deep sand burial decreased by 67.85%, 40.32%, 86.52% and 82.11%, respectively, while microbial biomass carbon, microbial abundance and enzyme activity decreased by 89.78%, 42.28%-79.66% and 69.51%-97.71%, respectively. There was no significant effect on crop productivity and soil quality with shallow sand burial treatment. The correlations analysis showed that there was significant positive correlations of both maize yield and above-ground biomass with soil silt and clay, soil organic carbon and total nitrogen contents, pH, electrical conductivity, soil water content, microbial abundance and biomass and all tested soil enzyme activities. Stepwise regression analysis indicated that soil water and total nitrogen contents, urease, cellobiohydrolase and peroxidase activities were key determining factors for maize productivity. This combination of factors explains reason of the decreased maize productivity with deep sand burial. We found that degradation of cropland as a result of sand burial changed soil physical-chemical properties and soil

关键词： sand burial soil quality enzyme activity maize productivity sandy cropland

Diversity and composition of culturable fungi in Horqin Sandy Land

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Research in Cold and Arid Regions 2022年第2期14卷 109-119页

作者： shaokun wang XueYong Zhao Hao Qu Jie Lian Fei wang FengHua Ding Urat Desert-grassland Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of ScienceLanzhouGansu 730000China Naiman Desertification Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of ScienceLanzhouGansu 730000China Key Laboratory of Stress Physiology and Ecology Gansu ProvinceLanzhouGansu 730000China Lishui University LishuiZhejiang 323000China

Soil fungi play a key role in soil functional performance and ecological *** understand the diversity and composition of culturable fungi in soils of Horqin Sandy Land,China,mobile dune,semi-fixed dune,fixed dune and sandy grassland were selected to investigate the soil fungal diversity using a traditional culture-dependent *** sequencing was applied to identify the fungal *** counts of culturable fungi increased significantly from mobile dune to sandy grassland along the gradient of sandy land *** Shannon-Wiener,Simpson and Evenness indices of culturable fungi ranged from 1.26-1.71,0.22-0.37 and 0.83-0.87,respectively.A total of 27 fungal strains were isolated using dilution plate cultural *** 27 fungal isolates were clustered into three groups:Ascomycota,Basidiomycota and Mucoromycota at phylum level,indicating that Ascomycota was the dominant fungal phylum(88.9%of the total).The isolated fungi were grouped into 3 phyla,5 classes,6 orders,11 families and 13 *** results show that culturable fungi were diverse in sandy land soils and fungal isolates have potential function in lipid turnover,cellulose degradation and ethanol,glucose and fatty acid *** studies should be carried out to explore their ecological and biological function for degraded sandy land restoration.

关键词： Culturable fungi fungal diversity ITS sequences phylogenetic analysis Horqin Sandy Land

Effect of spatial scale and topography on spatial heterogeneity of soil seed banks under grazing disturbance in a sandy grassland of Horqin Sand Land, Northern China

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Journal of Arid Land 2012年第2期4卷 151-160页

作者： XiaoAn ZUO shaokun wang XueYong ZHAO WenJin LI Johannes KNOPS Amy KOCHSlEK Naiman Desertification Research Station Cold and Arid Regions of Environmental and Engineering Research Institute Chi- nese Academy of Sciences Lanzhou 730000 China Laboratory of Plant Stress Ecophysiology and Biotechnology CAREERI Chinese Academy of Sciences Lanzhou 730000 China Key Laboratory of Arid and Grassland Ecology of Ministry of Education Lanzhou University Lanzhou 730000 China School of Biological Sciences University of Nebraska-Lincoln Lincoln 62588 USA

Soil seed banks play an important role in the distribution and composition of plant communities in semiarid grassland ecosystems. However, information on how spatial scale influences the spatial heterogeneity of soil seed banks in a grassland under grazing disturbance is still lacking. Based on field sampling and greenhouse germination, we measured the species composition and seed density of soil seed banks at different spatial scales （30 mx30 m, 30 mx60 m and 30 mx90 m） along a topographical gradient in a sandy grassland in Horqin Sand Land, Northern China. By applying geostatistical methods, we examined how spatial scale and topography affected the spatial distribution of soil seed banks in the study area. Our results showed that the total number of species in soil seed banks, as well as the number of dominant annuals, increased with the increase of spatial scales. Seed density in soil seed banks decreased with the increase of spatial scales due to an increase in the slopes and relative heights of the sampling points. Geostatistical analysis showed that the relative structural variance （C/（C0＋C）） of seed density and species richness were over 65% for all spatial scales, indicating that these variables had an ob- vious spatial autocorrelation and the spatial structured variance accounted for the largest proportion of the total sample variance. Spatial autocorrelation of seed density in soil seed banks increased with the increase of measured scales, while that of species richness showed a reverse trend. These results suggest that the total number of spe- cies in soil seed banks is spatial scale dependent and lower topography may accommodate more seeds. Spatial distribution of seed density in soil seed banks is also scale dependent due to topographic variation. Grassland management, therefore, needs to consider local grazing disturbance regime, spatial scale and topography.

关键词： sandy grassland grazing disturbance topographic variation seed density species richness scale dependence Inner Mongolia

Design and experimental investigation of potential low-thermalconductivity high-entropy rare-earth zirconates

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Journal of Advanced Ceramics 2024年第8期13卷 1132-1142页

作者： Lu Liu Hongying Dong Peng Zhang shaokun wang Haolei Qil Mengyu Ding Zhefeng Li Yu Bai Wen Ma School of Chemical Engineering Inner Mongolia University of TechnologyHohhot 010051China Inner Mongolia Key Laboratory of Thin Film and Coatings School of Materials Science and EngineeringInner Mongolia University of TechnologyHohhot 010051China

Developing new high-entropy rare-earth zirconate(HE-RE_(2)Zr_(2)O_(7))ceramics with low thermal conductivity is essential for thermal barrier coating *** this work,the average atomic spacings,interatomic forces,and average atomic masses of 16 rare-earth elements occupying the A site of the cubic A_(2)B_(2)O_(7) crystal structure were calculated by density functional *** three physical qualities,as vectors,characterize the corresponding rare-earth *** distance between two vectors quantitatively describes the difference between two rare-earth *** greater differences between two rare-earth elements,the disorder degree of HE-RE_(2)Zr_(2)O_(7)is greater,and therefore,the thermal conductivity is *** to the theoretical calculations,the thermal conductivity of the ceramics gradually increases in the order of(SC_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)0_(7),(SC_(0.2)Ce_(0.2)Nd_(0.2)Eu_(0.2)Gd_(0.2))_(2)Zr_(2)0_(7),(SC_(0.2)Y_(0.2)Tm_(0.2)Yb_(0.2)Lu_(0.2))_(2)Zr_(2)0_(7),and(Sc_(0.2)Er_(0.2)Tm_(0.2)Yb_(0.2)Lu_(0.2))_(2)Zr_(2)O_(7).Using the solution precursor plasma spray method and pressureless sintering method,four types of HE-RE2Zr2Oz powder and bulk samples were *** samples all showed a single defective fluorite structure with a uniform distribution of the elements and a stable phase *** thermal conductivities of the sintered HE-RE_(2)Zr_(2)0_(7) bulk samples ranged from 1.30 to 1.45 Wm^(-1).K^(-1) at 1400℃,and their differences were consistent with the theoretical calculation *** the ceramics,(Sc_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)O_(7) had the lowest thermal conductivity(1.30 W·m^(-1)·K^(-1),1400℃),highest thermal expansion coefficient(10.19×10^(-6) K^(-1),200-1400℃),highest fracture toughness(1.69±0.28 MPa·m^(1/2)),and smallest brttleness index(3.03μm^(1/2)).Therefore,(Sc_(0.2)Y_(0.2)La_(0.2)Ho_(0.2)Yb_(0.2))_(2)Zr_(2)0_(7)is considered to be an ideal candidate material for

关键词： high-entropy ceramics rare-earth zirconate(HE-RE_(2)Zr_(2)O_(7)) composition design thermal conductivity thermal barriercoatings(TBCs)

Accumulation of soil organic carbon during natural restoration of desertified grassland in China's Horqin Sandy Land

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Journal of Arid Land 2015年第3期7卷 328-340页

作者： YuQiang LI XueYong ZHAO FengXia ZHANG Tala AWADA shaokun wang HaLin ZHAO TongHui ZHANG YuLin LI Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences School of Environmental and Municipal Engineering Lanzhou Jiaotong University School of Natural Resources University of Nebraska

China＇s Horqin Sandy Land,a formerly lush grassland,has experienced extensive desertification that caused considerable carbon（C） losses from the plant-soil *** restoration through grazing exclusion is a widely suggested option to sequester C and to restore degraded *** a desertified grassland,we investigated the C accumulation in the total and light fractions of the soil organic matter from 2005 to 2013 during natural *** a depth of 20 cm,the light fraction organic carbon（LFOC） storage increased by 221 g C/m2（84%） and the total soil organic carbon（SOC） storage increased by 435 g C/m2（55%）.The light fraction dry matter content represented a small proportion of the total soil mass（ranging from 0.74% in 2005 to 1.39% in 2013）,but the proportion of total SOC storage accounted for by LFOC was remarkable（ranging from 33% to 40%）.The C sequestration averaged 28 g C/（m2·a） for LFOC and 54 g C/（m2·a） for total *** total SOC was strongly and significantly positively linearly related to the light fraction dry matter content and the proportions of fine sand and silt＋*** light fraction organic matter played a major role in total SOC *** results suggest that grazing exclusion can restore desertified grassland and has a high potential for sequestering SOC in the semiarid Horqin Sandy Land.

关键词： carbon storage carbon sequestration soil light fraction restoration grazing exclusion

Slippery quartz surfaces for anti‐fouling optical windows

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Droplet 2023年第1期2卷 47-55页

作者： Minjing Li Tongzhen Yang Qing Yang shaokun wang Zheng Fang Yang Cheng Xun Hou Feng Chen School of Mechanical Engineering Xi'an Jiaotong UniversityXi'anChina State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information School of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'anChina

The surface of camera‐based medical devices is easily smeared by blood and fog during the surgical procedure,causing visual field loss and bringing great distress to both doctors and *** this article,a slippery liquid‐infused porous surface(SLIPS)on a quartz window surface that can repel various liquids,especially blood droplets is reported.A femtosecond laser pulse train was used to create periodic microhole structures on the silica *** subsequent low surface energy treatment and lubricant infusion led to the successful preparation of a slippery *** blood‐repellent windows exhibited high transparency,great antifogging,and antibacterial *** addition,the slippery ability of the as‐prepared surface exhibited outstanding stability since the surface could withstand harsh treatments/environments,such as repeated pipette scratches and immersion in different pH *** as‐prepared millimeter‐sized quartz samples with SLIPS were attached to the endoscope lens as a protective coating and could maintain high visibility after repeated immersion in *** believe that the coating developed in this study will provide inspiration for the design of next‐generation endoscopes or other camera‐guided devices that will resist fouling,keep clear vision,and reduce operation time,thus offering great potential applications in lesion diagnosis and therapy.

关键词： quartz fouling visibility