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A Method for Alpine wetland Delineation and Features of Border: Zoigê Plateau, China

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Chinese Geographical Science 2017年第5期27卷 784-799页

作者： ZHENG Yaomin NIU Zhenguo GONG Peng LI Mengna HU Lile WANG Lei YANG Yuxiang GU Hai-jun MU Jinrong DOU Gejia XUE Hui WANG Lin LI Hua DOU Gejie DANG Zhicairang State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Joint Center for Global Change Studies College of Global Change and Earth System Science(GCESS)Beo'ing Normal UniversityBeijing 100875China Chinese Research Academy of Environmental Sciences Beijing 100012China World-Wide Fund for Nature(China) Beijing 100006China Wildlife Management Bureau of Gansu Province Lanzhou 730050China wetland Management Center of sichuang Province Chengdu 610081China Gansu Gahai-Zecha national reserve administration Luqu CountyGansu Province 747200China sichuan zoige wetland national reserve administration Zoige CountySichuang Province 624500China Gansu First Meander of Yellow River national reserve administration Maqu CountyGansu Province 747300China

Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The zoige Plateau on the Qinghai-Tibet Plateau was used as a research site for research on alpine wetland delineation. Several studies have analyzed the spatiotemporal pattern and dynamics of these alpine wetlands, but none have addressed the issues of wetland boundaries. The objective of this work was to discriminate the upper boundaries of alpine wetlands by coupling ecological methods and satellite observations. The combination of Landsat 8 images and supervised classification was an effective method for rapid identification of alpine wetlands in the Zoig6 Plateau. Wet meadow was relatively stable compared with hydric soils and wetland hydrology and could be used as a primary indicator for discriminating the upper boundaries of alpine wetlands. A slope of less than 4.5° could be used as the threshold value for wetland delineation. The normalized difference vegetation index （NDVI） in 434 field sites showed that a threshold value of 0.3 could distinguish grasslands from emergent marsh and wet meadow in September. The median normalized difference water index （NDWI） of emergent marsh remained more stable than that of wet meadow and grasslands during the period from September until July of the following year. The index of mean density in wet meadow zones was higher than the emergent and upland zones. Over twice the number of species occurred in the wet meadow zone compared with the emergent zone, and close to the value of upland zone. Alpine wetlands in the three reserves in 2014 covered 1175.19 kin2 with a classification accuracy of 75.6%. The combination of ecological methods and remote sensing technology will play an important role in wetland delineation at medium and small scales. The correct differentiation between wet meadow and grasslands is the key to improving the accuracy of future wetland delineation.

关键词： alpine wetland delineation ecological methods remote sensing zoige Plateau

An evaluation of soil moisture from AMSR-E over source area of the Yellow River, China

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Research in Cold and Arid Regions 2019年第6期11卷 461-469页

作者： TangTang Zhang Mekonnen Gebremichael Akash Koppa XianHong Meng Qun Du Jun Wen Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCalifornia 90095-1593USA zoige wetland and Ecosystem Research Station NIEERZoigeSichuan 624500China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Atmospheric Sciences Chengdu University of Information TechnologyChengduSichuan 610225China

In this study,in-situ soil moisture measurements are used to evaluate the accuracy of three AMSR-E soil moisture prod ucts from NASA(national Aeronautics and Space administration),JAXA(Japanese Aerospace Exploration Agency)and VUA(Vrije University Amsterdam and NASA)over Maqu County,Source Area of the Yellow River(SAYR),*** sults show that the VUA soil moisture product performs the best among the three AMSR-E soil moisture products in the study area,with a minimum RMSE(root mean square error)of 0.08(0.10)m3/m3 and smallest absolute error of 0.07(0.08)m3/m3 at the grassland area with ascending(descending)***,the VUA soil moisture product is used to describe the spatial variation of soil moisture during the 2010 growing season over *** VUA soil moisture product shows that soil moisture presents a declining trend from east south(0.42 m3/m3)to west north(0.23 m3/m3),with good agreement with a general precipitation *** center of SAYR presents extreme wetness(0.60 m3/m3)dur ing the whole study period,especially in July,while the head of SAYR presents a high level soil moisture(0.23 m3/m3)in July,August and September.

关键词： AMSR-E soil moisture products soil moisture ground measurements source area of the Yellow River AMSR-E soil moisture products applicability

Degree of Humification in Fresh Litter from a Subtropical Mixed Plantation Forest in Southwest China

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 635-650页

作者： Fujia Wu Chengming You Jie Du Xiangjun Pei Ningfei Lei Bo Tan Huixing Song College of Landscape Architecture Sichuan Agricultural UniversityChengdu611130China Institute of Ecology&Forestry Sichuan Agricultural UniversityForestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan ProvinceChengdu611130China Jiuzhaigou national Nature reserve administration Aba Tibetan and Qiang Autonomous PrefectureAba623402China Institute of Ecological Environment Chengdu University of TechnologyChengdu610059China

The humification degree of fresh litter directly controls the accumulation of soil humus derived from plant litter,but very little information on this process is *** forests are well known to restrict soil fertility,which is often indicated by the soil humus *** this study,fresh litter was collected during different plant phenological stages during 2016 and 2017 in a mixed plantation in Southwest *** values of hue coefficientΔlogK(absorbance ratio of 400 nm and 600 nm on a logarithmic scale),optical density E4/E6(absorbance ratio of 400 nm and 600 nm)and A600/C(absorbance at 600 mm per mg of carbon per ml of extraction)and the concentration of extractable humus carbon(HC)were determined in four litter components(foliar,twigs,reproductive organs and miscellaneous)of the dominant species(Pterocarya stenoptera,Quercus acutissima,Cunninghamia lanceolata and Toxicodendron vernicifluum).All of the litter components exhibited obvious humification characteristics,and showed the highest concentration of extractable HC during the leaf maturation *** miscellaneous and foliar litters showed greater humification than the other litter *** components of Pterocarya stenoptera litter exhibited greater degrees of humification than those of the other species,with lowerΔlogK and E4/E6 values and higher A600/C *** litter from coniferous and evergreen species showed lower humification than that from broad-leaf and deciduous species regardless of the litter component *** present results provide new insights into the management of plantations and theoretical data to accurately improve the quality of plantations and maintain soil fertility under a global change.

关键词： Fresh litter humification plantations extractable humus carbon

Fecal DNA metabarcoding reveals the dietary composition of wintering Red-crowned Cranes(Grus japonensis)

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Avian Research 2023年第4期14卷 647-655页

作者： Hongyi Liu Wei Xu Nan Xu Wenwen Zhang Haoming Jiang Yongqiang Zhao Changhu Lu Ying Zhu Peng Xu The Co-Innovation Center for Sustainable Forestry in Southern China College of Life SciencesNanjing Forestry UniversityNanjing210037China administration Station of Castanopsis Kawakamii Nature reserve in Xinkou of Sanming Sanming365000China Research Center for Biodiversity Conservation and Biosafety State Environmental Protection Scientific Observation and Research Station for Ecological Environment of Wuyi MountainsBiodiversity Comprehensive Observation Station for Wuyi MountainsState Environmental Protection Key Laboratory on BiosafetyNanjing Institute of Environmental SciencesMinistry of Ecology and Environment of ChinaNanjing210042China Jiangsu Yancheng wetland national Nature reserve Yancheng224057China Institute of Qinghai Tibetan Plateau Southwest Minzu UniversityChengdu610041China wetland College Yancheng Teachers UniversityYancheng224051China

Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management *** Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast *** dietary studies of this bird focused mainly on its plant food composition based on field observations and microhistological ***,a total of 45 fecal samples were collected in November,December and January(15 fecal samples each month)from wintering cranes,and then subjected to a high throughput sequencing meta-barcoding approach to determine the primary plant(rbcL)and animal(COI)food items in their diet.A total of 230 operational taxonomic units(OTUs)of plant foods and 371 OTUs of animal foods were *** main plant foods in the wintering period were Miscanthus,Zea,and Hordeum genera,which were similar to those in the breeding and the migration *** agricultural and natural plants were detected,indicating a relatively broad dietary niche for this crane ***,the main animal foods were representatives of Theridiidae,Megascolecidae,and Agelenidae,in sharp contrast to previous *** higher number of small terrestrial arthropods in animal foods might be due to the indirect intake of *** composition of both plant and animal foods in the diet showed the highest diversity in December,while it was homogeneous in *** plant of Zea genus became the main source of nutrition in late winter,as supplementary feeding was performed in the reserve,which could help Red-crowned Cranes to get through the cold *** results obtained in this work would contribute to the development of effective conservation strategies for the Red-crowned Crane.

关键词： Dietary composition Dietary niche Metabarcoding Molecular diet analysis Red-crowned Crane

Do Larger and Older Individuals Occupy Better Areas in the Colony of Qinghai Toad-headed Agamas?

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亚洲两栖爬行动物研究:英文版 2023年第3期14卷 183-190页

作者： Eduard GALOYAN Natalia SOPILKO Anna KOVALYEVA Yin QI A.N.Severtsov Institute of Ecology and Evolution Moscow 119071Russia Lomonosov Moscow State University Leninskie Gori 1Moscow 119991Russia Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

Group living reduces the chances of *** is also true for burrowing animals,which use burrows as refuges to escape *** in the center of a colony is the safest because it offers access to the greatest number of burrows;however,it is stressful due to frequent aggressive interactions *** predicted that larger and older animals should occupy areas of a colony with a higher density of burrows than smaller and younger *** test this prediction,we observed individually marked Qinghai toad-headed agamas(Phynocephalus vlangalii)from a single colony late in the breeding season when females were *** of burrows was the highest and distance between them the shortest in the center of the *** encounters were more frequent in the central part of the colony than on its *** found a negative correlation between body size and distance to the center of the colony for females,but not for *** was no such correlation between age of individuals and distance to the center of the *** in this species likely compete with other females and males for central burrows in the colony even after mating season *** suggest that gravid females likely compete for the dense burrows within the central part of the colony mainly due to their relatively lower sprint speed and higher probability of being caught by a predator if they are not refuged in a burrow.

关键词： burrow distribution competition group living lizards Phrynocephalus space use

资源胁迫与放牧对青藏高原东缘高寒草甸植物相互作用的联合效应

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Journal of Plant Ecology 2023年第2期16卷 39-51页

作者： Li Mo Hao Yang Peng Luo Cheng-Xiang Mou Jun Wang Ecological Restoration and Biodiversity Conservation Key Laboratory of sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China sichuan Key Laboratory of Conservation Biology for Endangered Wildlife Chengdu Research Base of Giant Panda BreedingChengdu 610081China College of Chemistry and Life Sciences Sichuan Provincial Key Laboratory for Development and Utilization of Characteristic Horticultural Biological ResourcesChengdu Normal UniversityChengdu 611130China College of Environmental Science and Engineering China West Normal UniversityNanchong 637002China

胁迫梯度假说认为,植物之间的正相互作用频率随着胁迫程度的增加而增加。然而,在高寒草甸生态系统中,放牧干扰和资源胁迫对植物相互作用的联合效应仍不清楚。本研究通过对青藏高原东缘沙化高寒草甸两种优势种[沙生薹草(Carex praeclara... 详细信息

胁迫梯度假说认为,植物之间的正相互作用频率随着胁迫程度的增加而增加。然而,在高寒草甸生态系统中,放牧干扰和资源胁迫对植物相互作用的联合效应仍不清楚。本研究通过对青藏高原东缘沙化高寒草甸两种优势种[沙生薹草(Carex praeclara;不可食)和藏茴香(Carum carvi;可食)]的空间关联的研究,探讨了放牧和未放牧条件下,3种沙化水平(轻度、中度、重度)上植物相互作用的变化,以检验胁迫梯度假说在青藏高原东缘沙化高寒草甸的普遍性。研究结果表明,在无放牧干扰下,随着沙化程度的增加,沙生薹草和藏茴香的种内相互作用由正转化为负,而种间相互作用由负转化为正。然而,当放牧干扰存在时,各沙化水平下藏茴香的种内相互作用均为中性;在中等胁迫条件下,种间相互作用也由负转化为正,但在严重胁迫梯度下,种间正相互作用崩溃,这与胁迫梯度假说的预测不一致。本研究结果进一步证明,在高寒生态系统中,放牧强烈影响着种内和种间相互作用的平衡。

关键词：高寒草甸沙化梯度放牧种内和种间相互作用青藏高原胁迫梯度假说