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Journal of Environmental Sciences 2007年第2期19卷 217-221页

作者： XU Qiu-jin NIAN Yue-gang JIN Xiang-can YAN Chang-zhou LIU Jin Jiang Gao-ming Lake research center Chinese Research Academy of Environmental Sciences Beijing 100012 China quantitative Vegetation ecology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Effects of chitosan on a submersed plant, HydriUa verticillata, were investigated. Results indicated that H. verticillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand （COD）. Superoxide dismutase （SOD） activity and malondialdehyde （MDA） contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD （980 rag/L） and decreased with low COD （63 mg/L）, respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant ceils from the control experiment （untreated with chitosan） were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.

关键词： antioxdiant enaymes chitosan Hydrilla verticiUata malondialdehyde superoxide dismutase ultrastructure

Characteristics of regional climate change and pattern analysis on Ordos Plateau

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Journal of Environmental Sciences 2002年第4期14卷 568-576页

作者： LI Guo qing ZHENG Yuan run Laboratory of quantitative Vegetation ecology Institute of BotanyChinese Academy of SciencesBeijing 100093China.

The characteristics of precipitation, temperature and their combination determine the special ecological environment pattern of Ordos Plateau. Analyzing its evolutionary trend attributes to understanding the succession process of the ecological environment of Ordos Plateau and has crucial instructional significance on the ecological restoration research being conducted in this region. Four time scales, arranging from ten days, one month, one season(growing season contrasting to non growing season)to one year were adopted to analyze the climate data which included nearly 30 years and were collected by eight weather stations on Ordos Plateau. The results indicated that the mean annual temperature and the mean monthly temperature of February, September and December, had increased significantly during the late 30 years. The annual precipitation did not show significant changes but its distribution pattern had changed obviously. The ratio of precipitation of major growing season (May October)to annual precipitation had increased distinctively,and five counties' precipitation reached statistically significant level. And the ratio of precipitation of latter growing season (September)to one year decreased significantly while the ratio of non growing season(November next April)to one year changed insignificantly. The results showed that maybe the interaction of increased mean temperature and insignificant change of precipitation in non growing season was one of the reasons why the desertification of the region was deteriorating in recent years. Using some factors closely relating to vegetation succession such as mean annual temperature, mean annual precipitation, distributive pattern of precipitation, mean temperature of the coldest month, mean temperature of the warmest month, precipitation of the warmest month, mean temperature of growing season, precipitation of growing season, potential evapotranspiration(PET)and radiative dryness index(RDI), to synthetically anal

关键词： climate change climatic synthetical regionalization restoration ecology Ordos Plateau

Spatial distribution analysis on climatic variables in northeast China

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Journal of Environmental Sciences 2001年第2期13卷 247-251页

作者： SHANG Zong-Bo GAO Qiong YANG Dian-An YANG Zheng-Yu Laboratory of quantitative Vegetation ecology Institute of Botany The Chinese Academy of Sciences Beijing 100093 China

Information ecology is a new research area of modern ecology. Here describes the spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction in Northeast China. First, digital terrain models was built with large scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2) mean monthly data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climatic variables.

关键词： spatial distribution analysis climatic variables trend surface analysis information ecology

Applications of stable isotopes to study plant-animal relationships in terrestrial ecosystems

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Chinese Science Bulletin 2004年第22期49卷 2339-2347页

作者： WANG Jianzhu1,LIN Guanghui1,2,HUANG Jianhui1 & HAN Xingguo1 1.Key Laboratory of quantitative Vegetation Sciences and research center for Plant ecology and Biodiversity Conservation,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China 2.Department of Global ecology,Carnegie Institution of Washington,Stanford,CA 94305,USA Key Laboratory of quantitative Vegetation Sciences and research center for Plant ecology and Biodiversity Conservation Institute of Botany Chinese Academy of Sciences Beijing 100093 China Department of Global ecology Carnegie Institution of Washington Stanford CA 94305 USA

As natural tracers, stable isotopes have been extensively used in plant physiological, ecological and envi- ronmental research. Recently, animal physiological ecologists have also applied stable isotope techniques to study plant- animal relationships. The isotopic compositions of animal body generally reflect and integrate their diets over a time period ranging from hours to years to the lifetime of an indi- vidual. When animal living habitat changes or animals move to a new environment, the animal isotopic compositions will shift accordingly. Thus, stable isotope signatures of an ani- mal can truly reflect its food sources, habitat, distribution and movement patterns during a given time period. More- over, by analyzing animal-tissue isotopic compositions at different temporal scales, we can improve our understanding of animal adaptation to environmental changes. Stable iso- tope technique also provides an ideal tool to study animal foodweb relationship and community structure because of isotopic fractionation during the processes of nutrient as- similation by animals. Stable isotope technique can continu- ously measure animal trophic position in a foodweb, which can eventually reveal the predator-prey relationship and its role in determining matter balance and energy flow in the entire ecosystem. Stable isotope technique has been one of the most important and efficient tools in studying plant-animal relationship. In this paper, we first review recent advances in the application of stable isotope techniques to plant-animal relationship research then evaluate their advantages and disadvantages, and finally discuss some future directions associated with stable isotope applications to plant-animal relationship research.

关键词：稳定同位素植物-动物关联性食物来源营养水平动物迁移

Improved data gap-filling schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： ZHAO Peng Johannes LüERS Department of Micrometeorology University of Bayreuth Institute of ecology University of Innsbruck Member of Bayreuth center of ecology and Environmental research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. In this study we developed a modified gap-filling scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was explained as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-filling Net ecosystem exchange LAI

Evaluating the relative importance of predictors in Generalized Additive Models using the *** R package

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Plant Diversity 2024年第4期46卷 542-546页

作者： Jiangshan Lai Jing Tang Tingyuan Li Aiying Zhang Lingfeng Mao College of ecology and Environment Nanjing Forestry UniversityNanjing210037China research center of quantitative ecology Nanjing Forestry UniversityNanjing 210037China University of Chinese Academy of Sciences Beijing100049China Guangzhou Climate and Agro-meteorology center Guangzhou 511430China Guangdong Ecological Meteorological center Guangzhou 510640China

Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and ***,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a *** address this challenge,we developed an R package named *** calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical *** these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within *** illustrate the utility of the *** package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,*** believe that the *** package will improve the interpretation of results obtained from GAMs.

关键词： Average shared variance Coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)

Genitalia-associated microbes in insects

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Insect Science 2015年第3期22卷 325-339页

作者： Oliver Otti Animal Population ecology Animal Ecology I Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth Universitatsstrasse 30 95440 Bayreuth Germany

In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects. Apart from such rather specific relationships the role of opportunistic infections in the reproductive process has been widely neglected. Opportunistic microbes transmitted passively during mating might impose an energetic cost, as the immune system will need to be alert and will use resources to fight potential intruders. Through mating wounds and contaminated reproductive organs opportunistic microbes might be transferred to mating partners and even enter the body cavity. Females as the ＂receiving＂ sex are particularly likely to have evolved adaptations to avoid or reduce opportunistic infections. Males of several species show highly complex seminal fluids, which as well as containing components that influence a males＇ fertilization success, also possess antimicrobial substances. The role of antimicrobials in the reproductive process is not well understood. Some evidence hints at the protection of sperm against microbes, indicating a role for natural selection in shaping the evolution of reproductive traits. By highlighting the potential importance of microbes in sexual selection and their role in reproduction in general I will make a case for studies in sexual selection, especially the ones investigating postcopulatory processes, that should incorporate environmental, as well as genotypic variation, in reproductive traits.

关键词： genital microbiome interactions sexually transmitted microbes spermmicrobe

Do microsporidia function as ＂biological weapon＂ for Harmonia axyridis under natural conditions？

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Insect Science 2015年第3期22卷 353-359页

作者： Tobias Gegner Oliver Otti Simon Tragust Heike Feldhaar Animal Population ecology Department of Animal Ecology I Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth D-95440 Bayreuth Germany

Invasive alien species, such as the multicoloured Asian ladybird Harmonia axyridis, are often regarded as major drivers ofbiodiversity loss. Therefore understanding which characteristics or mechanisms contribute to their invasive success is important. Here the role of symbiotic microsporidia in the hemolymph of H. axyridis was investigated in the context of intraguild predation between wild-caught H. axyridis and the native ladybird species Coccinella septempunctata. The microsporidia were recently discussed to contribute to the unpalatability of Harmonia for other coccinellids during intraguild predation and to function as ＂biological weapons＂. In the present study, visual detection of microsporidia in hemolymph samples revealed that 73.5 % of H. axyridis were infected. Intraguild predation experiments between larvae of the two species showed a significant competitive advantage for H. axyridis, even against larger larvae of C. septempunctata. Adult C. septempunctata always killed and fed on H. axyridis larvae. However only 11.4 % （4 of 47） of C. septempunctata that fed on infected H. axyridis died within 4 months. In contrast to previous studies this suggests that microsporidia or harmonine, the chemical defense compound of H. axyridis, do not lead to death of C. septempunctata preying on larvae ofH. axyridis. Instead our results support the idea that competitive advantage during intraguild predation greatly facilitates the success of H. axyridis and that this may help this highly invasive species to outcompete native species. The impact of microsporidia on Harmonia itself as well as on interspecific interactions require further studies.

关键词： defensive symbiont endosymbiont Harmonia axyridis invasive species microsporidia

Altitudinal Pattern of Plant Species Diversity in Shennongjia Mountains, Central China

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Journal of Integrative Plant Biology 2005年第12期47卷 1431-1449页

作者： Chang-Ming ZHAO Wei-Lie CHEN Zi-Qiang TIAN Zong-Qiang XIE Laboratory of quantitative Vegetation ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China River and Coastal Environment research center Chinese Research Academy of Environmental Sciences Beijing 100012 China

One hundred and sixty plots, approximately every 100 m above sea level （a.s.1.） along an altitudinal gradient from 470 to 3 080 m a.s.1, at the southern and northern watershed of Mt. Shennongjia, China, were examined to determine the altitudinal pattern of plant species diversity. Mt. Shennongjia was found to have high plant species diversity, with 3 479 higher plants recorded. Partial correlation analysis and detrended canonical correspondence analysis （DCCA） based on plant species diversity revealed that altitude was the main factor affecting the spatial pattern of plant species diversity on Mt. Shennongjia and that canopy coverage of the arbor layer also had a considerable effect on plant species diversity. The DCCA based on species data of importance value further revealed that altitude gradient was the primary factor shaping the spatial pattern of plant species. In addition, the rule of the “mid-altitude bulge” was supported on Mt. Shennongjia. Plant species diversity was closely related to vegetation type and the transition zone usually had a higher diversity. Higher plant species diversity appeared in the mixed evergreen and deciduous broadleaved forest zone （900-1500 m a.s.1.） and its transition down to evergreen broadleaved forest zone or up to deciduous broadleaved forest zone. The largest plant species diversity in whole communities on Mt. Shennongjia lay at approximately 1 200 m a.s.1. Greatest tree diversity, shrub diversity, and grass diversity was found at approximately 1 500, 1 100, and 1 200 m a.s.l., respectively. The southern watershed showed higher plant species diversity than the northern watershed, with maximum plant species diversity at a higher altitude in the southern watershed than the northern watershed. These results indicate that Mt. Shennongjia shows characteristics of a transition region. The relationship between the altitudinal pattern of plant species diversity and the vegetation type in eastern China are also discussed and a hypothe

关键词： altitudinal pattern mid-altitude bulge Mt. Shennongjia plant species diversity.

Dominance of rock exposure and soil depth in leaf trait networks outweighs soil quality in karst limestone and dolomite habitats

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Forest Ecosystems 2024年第5期11卷 632-641页

作者： Min Jiao Jiawei Yan Ying Zhao Tingting Xia Kaiping Shen Yuejun He Forestry College Research Center of Forest EcologyGuizhou UniversityGuiyang550025China

Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional *** karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential communities,possibly due to habitat rock exposure,soil depth,and soil physicochemical properties variations,leading to a shift from plant trait variation to functional ***,how soil and habitat quality affect the differentiation of leaf trait networks remains *** were constructed for typical dolomite and limestone habitats by analyzing twenty-one woody plant leaf traits across fifty-six forest subplots in karst *** differences between dolomite and limestone LTNs were compared using network *** network association of soil and habitat quality was analyzed using redundancy analysis(RDA),Mantle's test,and a random forest *** limestone LTN exhibited significantly higher edge density with lower diameter and average path length when compared to the dolomite *** indicates LTN differentiation,with the limestone network displaying a more compact architecture and higher connectivity than the dolomite *** specific leaf phosphorus and leaf nitrogen contents of dolomite LTN,as well as the leaf mass and leaf carbon contents of limestone LTN,significantly contributed to network degree and closeness,serving as crucial node traits regulating LTN ***,both habitat LTNs significantly correlated with soil nitrogen and phosphorus,stoichiometric ratios,pH,and organic carbon,as well as soil depth and rock exposure rates,with soil depth and rock exposure showing greater relative *** depth and rock exposure dominate trait network differentiation,with the limestone habitat exhibiting a more compact network architecture than the dolomite habitat.

关键词： Leaf trait networks Functional traits Woody plant community Karst Dolomite Limestone