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What makes Haloxylon persicum grow on sand dunes while H. ammodendron grow on interdune lowlands: a proof from reciprocal transplant experiments

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Journal of Arid Land 2014年第5期6卷 581-591页

作者： GuiQing XU DanDan YU JiangBo XIE LiSong TANG Yan LI State key laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Determining the mechanisms underlying the spatial distribution of plant species is one of the central themes in biogeography and ecology. However, we are still far from gaining a full understanding of the autecological processes needed to unravel species distribution patterns. In the current study, by comparing seedling recruitment, seedling morphological performance and biomass allocation of two Haloxylon species, we try to identify the causes of the dune/interdune distribution pattern of these two species. Our results show the soil on the dune had less nutrients but was less saline than that of the interdune; with prolonged summer drought, soil water availability was lower on the dune than on the interdune. Both species had higher densities of seedlings at every stage of recruitment in their native habitat than the adjacent habitat. The contrasting different adaptation to nutrients, salinity and soil water conditions in the seedling recruitment stage strongly determined the distribution patterns of the two species on the dune/interdune. Haloxylon persicum on the dunes had lower total dry biomass, shoot and root dry biomass, but allocated a higher percentage of its biomass to roots and possessed a higher specific root length and specific root area by phenotypic traits specialization than that of Haloxylon ammodendron on the interdune. All of these allowed H. persicum to be more adapted to water stress and nutrient shortage. The differences in morphology and allocation facilitated the ability of these two species to persist in their own environments.

关键词： Haloxylon seedling recruitment root distribution biomass allocation species distribution

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Responses of soil nematode community to monoculture or mixed culture of a grass and a legume forage species in China

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Pedosphere 2020年第6期30卷 791-800页

作者： Yingying YE Yichao RUI Zhaoxia ZENG Xunyang HE Kelin WANG Jie ZHAO key laboratory of Agro-ecological processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Huanjiang Observation and Research Station for Karst Ecosystems Chinese Academy of SciencesHuanjiang 547100China Department of soil Science University of Wisconsin-MadisonMadison WI 53705USA University of Chinese Academy of Sciences Beijing 100049China

Mixed cultivation of fast-growing grasses and nitrogen(N)-fixing legumes for forage production is widely considered effective for obtaining sustained high forage yields without depleting soil N ***,the effects of monoculture and mixed culture of these species on soil food webs are poorly *** this study,soil nematode communities were examined as indicators of the soil food web structure of monoculture and mixed culture of grass and legume at three N levels,i.e.,338(low),450(moderate),and 675(high)kg N ha-1 year-1,across 2 years in wet and dry seasons,using the grass Paspalum wetsfeteini and the legume Medicago sativa(alfalfa),both commonly cultivated ***-measures analysis of covariance showed that compared with grass monoculture,legume monoculture and grass-legume mixture increased abundances of herbivorous,bacterivorous,and fungivorous nematodes in the soil food web under the low and moderate N fertilization *** response curve results showed that the abundance of Helicotylenchus,a plant parasite,was significantly higher under legume monoculture than other planting systems at the low N fertilization *** equation model analysis indicated that the legume increased bacterivore abundance,while increasing N fertilization decreased omnivore *** legume might increase the quantity and quality of food resources for soil biota,resulting in the bottom-up control of soil nematode *** results indicate that targeted control of a soilborne pathogen,Helicotylenchus,is required in alfalfa-based planting *** addition,high inorganic N application,which is detrimental to legume-rhizobia symbiosis,nullified the otherwise positive effects of legumes on soil nematodes.

关键词： bacterivore bottom-up control fertilization fungivore herbivore nitrogen soil food web soilborne pathogen

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Nitrogen Biological Cycle Characteristics of Seepweed(Suaeda salsa) Wetland in Intertidal Zone of Huanghe(Yellow) River Estuary

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Chinese Geographical Science 2012年第1期22卷 15-28页

作者： SUN Zhigao MOU Xiaojie SUN Jingkuan SONG Hongli YU Xiang WANG Lingling JIANG Huanhuan SUN Wanlong SUN Wenguang Shandong key laboratory for Eco-Environmental Science of Yellow River Delta Coastal Wetland Ecological Research Base of Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Binzhou 256603 China key laboratory of Coastal Environment processes of Chinese Academy of Sciences Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China key laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

From April 2008 to November 2009, the nitrogen （N） cycle of plant-soil system in seepweed （Suaeda salsa） wetland in the intertidal zone of the Huanghe （Yellow） River estuary was studied. Results showed that soil N had sig- nificant seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season （p 〈 0.01）. The N/P ratio （9.87 ±1.23） of S. salsa was less than 14, indicating that plant growth was limited by N. The N accumulated in S. salsa litter at all times during decomposition, which was ascribed to the N immobilization by microbes from the environment. soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low （0.0145 and 0.3844, respectively）, while the N cycle coefficient was high （0.7108）. The results of the N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 g/m2and 4.332 g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 g/m2 and 0.626 g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883 g/m2, the annual N return amount from litter to soil was more than 0.125（-） g/m2 （minus represented immobili- zation）, and the net N mineralization amount in topsoil （0-15 cm） in growing season was 1.190 g/m2. The assessment of N biological cycle status orS. salsa wetland indicated that N was a very important limiting factor and the ecosystem was situated in unstable and vulnerable status. The S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships determined in the compartment model might provide scientific base for us to reveal the special adaptive strategy orS. salsa to the vulnerable habitat in the following studies.

关键词： nitrogen biological cycle seepweed wetland Huanghe (Yellow) River estuary

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Allocation of nitrogen and carbon is regulated by nodulation and mycorrhizal networks in soybean/maize intercropping system

Allocation of nitrogen and carbon is regulated by nodulation...

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中国菌物学会第七届全国会员代表大会暨2017年学术年会

作者： Guihua Wang Lichao Sheng Dan Zhao Jiandong Sheng Xiurong Wang Hong Liao State key laboratory for Conservation and Utilization of Subtropical Agro-bioresources Root Biology Center South China Agricultural University xinjiang key laboratory of soil and plant ecological processes College of Grassland and Environmental Sciences Xinjiang Agricultural University Root Biology Center Fujian Agriculture and Forestry University

Eight species of ethno-medicinal plants（Artemisia annua, A. argyi, A. lactiflora,Camptotheca acuminate, Dendrobium catenatum, Ginkgo biloba, Nothapodytes Pittosporoides and Taxus chinensis var. mairei） from Guizhou province were involved the studies for the diversity of their endophytic fungi associated as well as the bioactive compounds and novel P-glycoprotein inhibitors from the fungi. From the organs of all the medicinal plants, more than 3000 fungal strains were isolated and identified via morphology and phyloheny, which belong to six class viz. Agaricomycetes,Dothideomycetes, Eurotiomycetes, Leotiomycetes, Microbotryomycetes, Sordariomycetes. Amongst them, nineteen funagl genera were isolated from A. annua in which dominant genera included Alternaria, Chaetomium, Cladosporium, Penicillium and Trichoderma. Fourteen fungal genera were found in A. argyi of which dominant genera included Chaetomium, Penicillium, Phomopsis and Trichoderma. Sixteen fungal genera were identified in A. lactiflora in which dominant genera included Phomopsis and Xylaria. Twenty-two fungal genera were isolated from Taxus chinensis var. mairei of which dominant genera included Alternaria and Bjerkandera. Twenty fungal genera were isolated from Camptotheca acuminate in which dominant genera included Scolecobasidium and ***-three fungal genera were isolated from Ginkgo biloba of which dominant genera included Alternaria, Curvularia, Paecilomyces and Pestalotiopsis. Meanwhile, Colletotrichum, Diaporthe and Phyllosticta dominated in 1037 endophytic fungi isolated from Nothapodytes Pittosporoides and Colletotrichum and Xylaria dominated in more than 500 endophytic fungi from Dendrobium catenatum.A combination of bioactive, chemical and genetic methods was applied to screen the bioactivity of of endophytic fungi and their chemical compounds. The results showed that two strains GQH02（Alternaria alternata） and GYX06（Pestalotiopsis microspora） had strong bioactivities and rich metabolit

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Community structure and carbon and nitrogen storage of sagebrush desert under grazing exclusion in Northwest China

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Journal of Arid Land 2020年第2期12卷 239-251页

作者： DONG Yiqiang SUN Zongjiu AN Shazhou JIANG Shasha WEI Peng College of Pratacultural and Environmental Science Xinjiang Agricultural UniversityUrumqi 830052China key laboratory of Grassland Resources and Ecology of xinjiang Urumqi 830052China Post-doctoral Mobile Station of xinjiang Agricultural University Urumqi 830052China

Overgrazing is regarded as one of the key factors of vegetation and soil degradation in the arid and semi-arid regions of Northwest *** exclusion(GE)is one of the most common pathways used to restore degraded grasslands and to improve their ecosystem ***,there are still significant controversies concerning GE’s effects on grassland diversity as well as carbon(C)and nitrogen(N)*** remains poorly understood in the arid desert regions,whilst being essential for the sustainable use of grassland *** assess the effects of GE on community characteristics and C and N storage of desert plant community in the arid desert regions,we investigated the community structure and plant biomass,as well as C and N storage of plants and soil(0-100 cm depth)in short-term GE(three years)plots and adjacent long-term freely grazing(FG)plots in the areas of sagebrush desert in Northwest China,which are important both for spring-autumn seasonal pasture and for ecological *** findings indicated that GE was beneficial to the average height,coverage and aboveground biomass(including stems,leaves and inflorescences,and litter)of desert plant community,to the species richness and importance values of subshrubs and perennial herbs,and to the biomass C and N storage of aboveground parts(Psoil layers(Pplant density,belowground biomass,and soil organic C concentration and C storage in the 0-100 cm soil layer could not be significantly changed by short-term GE(three years).The results suggest that,although GE was not beneficial for C sequestration in the sagebrush desert ecosystem,it is an effective strategy for improving productivity,diversity,and C and N storage of *** a result,GE can be used to rehabilitate degraded grasslands in the arid desert regions of Northwest China.

关键词： grazing exclusion desert plant community biomass C storage N storage fencing arid desert regions

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Environmental drivers of soil microbial activity and diversity along an elevational gradient

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Journal of Mountain Science 2022年第5期19卷 1336-1347页

作者： PENG Si-li GE Zhi-wei LIU Gang-cai MAO Ling-feng Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China key laboratory of Mountain Surface processes and ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of ScienceChengdu 610041China

Microbial functional and structural patterns and drivers along elevational gradients have recently received increasing *** this study,we examined soil bacterial and fungal community diversity,compositions,and microbial activities(i.e.,soil basal respiration and extracellular enzyme activities)across an elevational gradient from 1148 m to 2080 m(consists of six elevations)in the Yuanmou dry-hot valley located in Southwest *** factors,including soil temperature,moisture content,pH,soil organic carbon(SOC),total nitrogen(TN),the C/N ratio,total phosphorus(TP),and aboveground plant biomass were also *** results showed that soil bacterial alpha diversity(Shannon index)was unaffected by elevation,whereas fungal alpha diversity firstly increased significantly from 1148 m to 1539 m but did not increase further at higher *** Shannon index was significantly correlated with SOC,whereas fungal Shannon index was remarkably associated with soil *** activity,beta diversities and community composition varied with elevation,but none of them showed a consistent *** Carlo test revealed that soil moisture followed by temperature,and pH,were the primary drivers of bacterial community *** fungal community composition significantly depended on soil ***,our study suggested bacterial diversity and composition were determined by climatic(moisture and temperature)and edaphic properties(SOC and pH),while fungal diversity and composition were structured mainly by climatic *** findings may contribute to a better understanding of microbial responses along elevational gradients in this semi-arid region.

关键词： Bacteria Fungi Composition and diversity Basal respiration Enzyme activity

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Spatio-temporal pattern and changes of evapotranspiration in arid Central Asia and xinjiang of China

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Journal of Arid Land 2012年第1期4卷 105-112页

作者： Xi CHEN BaiLian LI Qin LI JunLi LI Saparnov ABDULLA State key laboratory of Desert and Oasis Ecology Sino-US International Center of Ecology in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China ecological Complexity and Modeling laboratory Department of Botany and Plant Sciences University of California Riverside CA 92521-0124 USA University of Jinan Jinan 250022 China U.U.Uspanov Kazakh Research Institute of soil Science and Agrichemistry Ministry of Agriculture of Kazakhstan Almaty 050060. Kazakhstan

Accurate inversion of land surface evapotranspiration （ET） in arid areas is of great significance for understanding global eco-hydrological process and exploring the spatio-temporal variation and ecological response of water resources. It is also important in the functional evaluation of regional water cycle and water balance, as well as the rational allocation and management of water resources. This study, based on model validation analysis at varied scales in fiwe Central Asian countries and China＇s xinjiang, developed an appropriate approach for ET inversion in arid lands. The actual ET during growing seasons of the study area was defined, and the changes in water participating in evaporation in regional water cycle were then educed. The results show the simulation error of SEBS （Surface Energy Balance System） model under cloud amount consideration was 1.34% at 30-m spatial scale, 2.75% at 1-km spatial scale and 6,37% at 4-kin spatial scale. ET inversion for 1980-2007 applying SEBS model in the study area indicates：（1） the evaporation depth （May-September） by land types descends in the order of waters （660.24 ram）〉 cultivated land （464.66 mm）〉 woodland （388.44 mm）〉 urbanized land （168.16 mm）〉 grassland （160.48 mm）〉 unused land （83.08 mm）; and （2） ET during the 2005 growing season in xinjiang and Central Asia was 2,168.68x108 m3 （with an evaporation/precipitation ratio of 1.05） and 9,741.03x108 m3 （with an evaporation/precipitation ratio of 1.4）, respectively. The results unveiled the spatio-temporal variation rules of ET process in arid areas, providing a reference for further research on the water cycle and water balance in similar arid regions.

关键词： Evapotranspiration (ET) arid areas SEBS model remote sensing Central Asia xinjiang of China

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Arbuscular mycorrhizal fungi infection in desert riparian forest and its environmental implications: A case study in the lower reach of Tarim River

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Progress in Natural Science:Materials International 2008年第8期18卷 983-991页

作者： Yuhai Yang, Yaning Chen *, Weihong Li key laboratory of Oasis Ecology and Desert Environment, xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China key laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

This study was conducted on the desert riparian forest along the lower reach of the inland Tarim River, which is located in the arid region of Northwest *** plant species in 10 families were collected from five monitoring sections,and examined for the infection of arbuscular mycorrhizal fungi (AMF). The impact of different soil factors on AMF infection rate and intensity was compared using the principal component analysis (PCA) method. The results indicate that 11 species are AM and only 4 are non-AM plants. The estimated capacity of AMF infection depends on families of plants and also the parameters (infection rate, infection intensity, fungal spore density) used. The density of fungal spores was relatively higher in Phragmites communis and Populus euphratica in Graminaceae and Salicaceae families, *** infection rate was above 50%in all the AM plants,except Calligonum *** highest infection rate appeared in Alhagi sparsifolia (97%) and Glycyrrhiza inflata (92%). However, when compared by AMF infection intensity, Tamarix spp. became the top one, followed by Alhagi sparsifolia, and Glycyrrhiza inflata was in the middle range of all the species. The PCA has identified that soil total salt, moisture, organic matter, total nitrogen, total P, available K and pH were closely associated with the AMF infection.

关键词： Arbuscular mycorrhiza Infection ecological restoration Desert riparian forest soil

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Experimental evidence for weakened tree nutrient use and resorption efficiencies under severe drought in a subtropical monsoon forest

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Journal of plant Ecology 2020年第5期13卷 649-656页

作者： Xiao-Ni Xu Jian-Yang Xia Xu-Hui Zhou Li-Ming Yan Zhejiang Tiantong Forest Ecosystem National Observation and Research Station Shanghai Key Lab for Urban Ecological Processes and Eco-RestorationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China Research Center for Global Change and ecological Forecasting East China Normal UniversityShanghai 200241China

Aims The functions of global forests are threatened by the increasing frequency of severe *** to drought inducing reductions in soil nutrient availability,efficiencies of nutrient use and resorption of trees become crucial for forest functions and biogeochemical ***,understanding the dynamics of responses of foliar nutrient use and resorption efficiencies to drought,especially in tropical or subtropical forests,is still *** goal was to detect whether and how the importance of leaf nutrient use and resorption changes across different species in the hot and wet forests when suffering drought stress in different *** Based on a 70%throughfall exclusion experiment in a subtropical forest,we collected green and senesced leaves of Schima superba and Lithocarpus glaber in different months from October 2016 to May 2019,to estimate the effects of drought on leaf nitrogen(N)and phosphorus(P)use and resorption efficiencies(*** and PUE,NRE and PRE).Important Findings The effects of drought on nutrient use and resorption efficiencies varied between species and *** on a 2-year observation,drought had no effect on ***,but significantly decreased NUE,NRE and PRE of *** by 3.4%,20.2%and 7.1%,***,the negative drought effects were aggravated by the natural summer drying in *** a result,NUE and PUE of *** were significantly depressed by 17.2%and 58.1%,while NRE and PRE were significantly reduced by 56.5%and 53.8%in August ***,the responses of NRE,PRE and NUE to drought were related with soil moisture(SM)for ***,and when SM decreased to a threshold near 9 v/v%,drought effects were shifted from unresponsive to *** results highlight a species-specific threshold response of nutrient use under drought in a subtropical forest.

关键词： drought nitrogen nutrient resorption efficiency nutrient use efficiency phosphorus subtropical forest

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Grazing exclusion-induced shifts,the relative importance of environmental filtering,biotic interactions and dispersal limitation in shaping desert steppe communities,northern China

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Journal of Arid Land 2018年第3期10卷 402-415页

作者： WANG Xing SONG Naiping YANG Xinguo WANG Lei CHEN Lin Breeding Base for State key laboratory of Land Degradation and ecological Restoration in Northwest China Ningxia University School of Agriculture Ningxia University

Grazing exclusion is one of the most efficient approaches to restore degraded grassland but may negatively affects the recovery of species diversity. Changes in plant species diversity should be a consequence of the ecological assembly process. Local community assembly is influenced by environmental filtering, biotic interactions, and dispersal. However, how these factors potentially contribute to changes to species diversity is poorly understood, especially in harsh environments. In this study, two management sites within a Stipa breviflora desert steppe community（typical natural steppe） were selected in northern China. In one of the two management sites, grazing has been excluded since 2010 and in the other with open grazing by sheep. In August 2016, three plots were established and 100 sampling units were created within each plot in a 5 m×5 m area at the two management sites. To assess the effects of grazing exclusion on S. breviflora steppe, we analyzed the vegetation biomass, species diversity,soil organic carbon, and soil particle size distribution using paired T-tests. In addition, variation partitioning was applied to determine the relative importance of environmental filtering and dispersal limitation. Null mode analysis was used to quantify the influence of biotic interactions in conjunction with Eco Sim niche overlap and co-occurrence values. Our results demonstrated that（1） species diversity significantly decreased and the main improvements in soil quality occurred in the topsoil 0–10 cm after the grazing exclusion;（2） environmental filtering was important for community assembly between grazed and fenced grassland and this appears particularly true for soil particle size distribution, which may be well correlated with soil hydrological processes; and（3） however, competitive exclusion may play a significant role within the exclusion. The multiple pathways of assembly may collectively determine negative effects on the restoration of species diversity. Ther

关键词： community assembly environmental filtering Stipa breviflora desert steppe semi-arid grassland

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