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Using resistance distance from circuit theory to model dispersal through habitat corridors

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Journal of Plant ecology 2018年第3期11卷 385-393页

作者： Jan Thiele Sascha Buchholz Jens Schirmel institute of landscape ecology University of MünsterHeisenbergstr.2Münster 48149Germany Department of ecology TU BerlinRothenburgstr.12Berlin 12165Germany Berlin-Brandenburg institute of Advanced Biodiversity Research(BBIB) Altensteinstr.34Berlin 14195Germany institute of Environmental Sciences University Koblenz-LandauFortstr.7Landau 76829Germany

Aims Resistance distance(RD),based on circuit theory,is a promising metric for modelling effects of landscape configuration on dispersal of organ-isms and the resulting population and community *** values of RD reflect the likelihood of a random walker to reach from a source to a certain destination in the *** it has successfully been used to model genetic structures of animal populations,where it most often outperforms other isolation metrics,there are hardly any applications to plants and,in particular,to plant community *** aims were to test if RD was a suitable metric for studying dispersal processes of plants in narrow habitat corridors(linear landscape ele-ments[LLE]).This would be the case,if dispersal processes(seed dis-persal and migration)resembled random ***,we compared the model performance of RD against least-cost distance(LCD)and Euclidean distance(ED).Finally,we tested the suitability of different cost surfaces for calculations of LCD and *** We used data from 50 vegetation plots located on semi-natural LLE(field margins,ditches,road verges)in eight agricultural landscapes of Northwest *** mapped LLE,including hedges and tree rows,from aerial images in a Geographic Information System,con-verted the maps into raster layers,and assigned resistance values to the raster cells,where all cells outside of LLE received infinite resist-ance and,thus,represented barriers to *** all pairs of plots within study areas,we calculated Jaccard similarity assuming that it was a proxy(or correlate)of dispersal events between ***,we calculated RD and LCD of the network of LLE and ED between the *** modelled the effects of distance metrics on community similarity using binomial generalized linear mixed *** Findings ED was clearly the least suitable isolation ***,we found that RD performed better than LCD at modelling Jaccard *** varied markedly betwee

关键词： connectivity floristic similarity isolation landscape migration least-cost distance

Predicting the impacts of climate change on nonpoint source pollutant loads from agricultural small watershed using artificial neural network

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Journal of Environmental Sciences 2010年第6期22卷 840-845页

作者： Eunjeong Lee Chounghyun Seong Hakkwan Kim Seungwoo Park Moonseong Kang Department of landscape Architecture and Rural Systems Engineering Research institute for Agricultural & Life Sciences Seoul National University

This study described the development and validation of an artificial neural network （ANN） for the purpose of analyzing the effects of climate change on nonpoint source （NPS） pollutant loads from agricultural small watershed. The runoff discharge was estimated using ANN algorithm. The performance of ANN model was examined using observed data from study watershed. The simulation results agreed well with observed values during calibration and validation periods. NPS pollutant loads were calculated from load-discharge relationship driven by long-term monitoring data. LARS-WG （Long Ashton Research Station-Weather Generator） model was used to generate rainfall data. The calibrated ANN model and load-discharge relationship with the generated data from LARS-WG were applied to analyze the effects of climate change on NPS pollutant loads from the agricultural small watershed. The results showed that the ANN model provided valuable approach in estimating future runoff discharge, and the NPS pollutant loads.

关键词： artificial neural network climate change LARS-WG nonpoint source pollution runoff

How forest edge-center transitions in the herb layer interact with beech dominance versus tree diversity

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Journal of Plant ecology 2016年第5期9卷 498-507页

作者： Claudia Normann Teja Tscharntke Christoph Scherber Department of Crop Sciences University of GöttingenGrisebachstraße 637077 GöttingenGermany institute of landscape ecology University of MünsterHeisenbergstraße 248149 MünsterGermany

Aims Forest fragmentation and the associated augmentation of forest edge zones are increasing *** edges are characterized by altered plant species richness and community *** the tree layer and its species composition has been shown to influence herb layer composition,changes in tree species composition or richness may weaken or strengthen edge effects in forest *** studied effects of the edge-center transition,tree species composition and their potential interaction on the understory vegetation in the Hainich National Park,Germany’s largest connected deciduous forest,allowing to cover large edge-center *** We established 12 transects in an area of 75 km^(2) of continuous forest,6 beech-dominated and 6 in multispecies forest *** transect reached from the forest edge up to 500 m into the forest *** relevés were conducted in regular,logarithmic distances along each *** Findings Herb species richness was influenced by an interaction of edge effects and tree diversity *** increasing distance from the forest edge,herb species richness remained constant in multispecies forest stands but rapidly decreased in beech-dominated forest ***,herb richness was higher in the interior of multispecies forest *** forest specialists increased and percent generalists decreased with distance from the edge and this contrasting pattern was much more pronounced in beech-dominated *** using structural equation modeling,we identified litter depth mediated by tree species composition as the most important driver of herb layer plant species richness.

关键词： community composition Fagus sylvatica functional groups habitat specialists and generalists litter depth tree diversity

Retarded Embryo Development 1(RED1) regulates embryo development,seed maturation and plant growth in Arabidopsis

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Journal of Genetics and Genomics 2016年第7期43卷 439-449页

作者： Qian Du Huanzhong Wang Department of Plant Science and landscape Architecture University of Connecticut institute for Systems Genomics University of Connecticut

Plant seeds accumulate large amounts of protein and carbohydrate as storage reserves during matura- tion. Thus, understanding the genetic control of embryo and seed development may provide bioengi- neering tools for yield improvement. In this study, we report the identification of Retarded Embryo Development1 （RED1） gene in Arabidopsis, whose two independent T-DNA insertion mutant lines, SALK_085642 （red1-1 ） and SALK_022583 （red1-2）, show a retarded embryo development phenotype. The embryogenesis process ceases at the late heart stage in red1-1 and at the bent-cotyledon stage in red1-2, respectively, resulting in seed abortion in both lines. The retarded embryo development and seed abortion phenotypes reverted to normal when REDI complementation constructs were introduced into mutant plants. Small redl-2 homozygous plants can be successfully rescued by culturing immature seeds, indicating that seed abortion likely results from compromised tolerance to the desiccation process associated with seed maturation. Consistent with this observation, redl-2 seeds accumulate less protein, and the expression of two late embryo development reporter transgenes, LEA：：GUS and β-con- glycinin：：GUS, was significantly weak and started relatively late in the redl-2 mutant lines compared to the wild type. The REDI gene encodes a plant specific novel protein that is localized in the nucleus. These results indicate that RED1 plays important roles in embryo development, seed maturation and plant growth.

关键词： Embryo Development Seed maturation Growth Arabidopsis

Long-term variability of air temperature and precipitation conditions in the Polish Carpathians

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Journal of Mountain Science 2018年第2期15卷 237-253页

作者： Agnieszka WYPYCH Zbigniew USTRNUL Dirk R.SCHMATZ Department of Climatology Jagiellonian University landscape Dynamics Unit Swiss Federal Research Institute WSL

Mountain regions are sensitive to climate changes, which make them good indicators of climate change. The aim of this study is to investigate the spatial and temporal variability of air temperature and precipitation in the Polish Carpathians. This study consists of climatological analyses for the historical period 1851-2010 and future projections for 2021-2100. The results confirm that there has been significant warming of the area and that this warming has been particularly pronounced over the last few decades and will continue in the oncoming *** change is most evident in the foothills;however, these are the highest summits which have experienced the most intensive increases in temperature during the recent period. Precipitation does not demonstrate any substantial trend and has high year-to-year variability. The distribution of the annual temperature contour lines modelled for selected periods provides evidence of the upward shift of vertical climate zones in the Polish Carpathians,which reach approximately 350 meters, on average,what indicates further ecological consequences as ecosystems expand or become extinct and when there are changes in the hydrological cycle.

关键词： Climate change Air temperature Precipitation Polish Carpathians

Boundless love:a German Professor Uli Schwarz in China

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Protein & Cell 2024年第8期15卷 553-558页

作者： Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China

More than 20 years ago,an old German man embarked on a quest to explore the suburbs of Shanghai and the villages of jiangsu Province in search of antique Chinese *** was not a mere antique collector or aficionado of ancient furmiture,but a German scientist motivated by his profound love of Chinese *** name was Uli Schwarz(Fig.1),a distinguished German scientist who had dedicated the majority of his life to promoting cross-cultural scientific exchanges,an effort that left an indelible mark on the landscape of research collaborations between China and Germany.

关键词： Schwarz German landscape

Water resource formation and conversion and water security in arid region of Northwest China

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Journal of Geographical Sciences 2016年第7期26卷 939-952页

作者：陈亚宁李宝富李稚李卫红 State Key Laboratory of Desert and Oasis ecology Xinjiang Institute of Ecology and Geography CAS College of Geography and Tourism Qufu Normal University

Climate change and water resource issues are global problems of common concern to the international community, and they are major bottlenecks affecting the eco-environment and sustainable socio-economic development in the arid region of Northwest China. On the basis of results from previous studies, this paper points out that the unique landscape of Northwest China increases the complexity and uncertainty of the climate system. This paper analyzes the key constraints on socio-economic development and ecological security in the region, discusses the impact of climate change on water resources in Northwest China, identifies common themes and the main problems present in research on climate change and water resources in the arid northwest region, and finally, based on the importance and urgency of conducting research on the region＇s water resources, proposes scientific problems that need to be addressed： first, the impact of climate change on the formation, conversion and future trends of water resources in the region; second, bidirectional coupling of high-resolution regional climate models and water cycle models of arid region land surface patterns; third, the impact of climate change and human activities on water resources of the arid northwest region. Through consideration and discussion of the above, this paper seeks to further clarify specific areas of research on pressing issues related to climate change and water resources in Northwest China, so as to establish a solid scientific basis for significantly enhancing our ability to respond to climate change and water shortages.

关键词： climate change water resources arid areas Northwest China

Divergent responses of Picea crassifolia *** different forest patches to climate change in the northeastern Tibetan Plateau

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Forest Ecosystems 2023年第6期10卷 752-762页

作者： Zhongtong Peng Qifeng Mo Liangjun Zhu Qingao Lu Jiaqing Cai Mingming Guo Kun Xu Yuandong Zhang Key Laboratory of Forest ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm College of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou510642China National Engineering Laboratory for Applied Technology of Forestry&ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha410004China Swiss Federal institute for Forest Snow and Landscape Research WSLBirmensdorf8903Switzerland Environment and Sustainability institute University of ExeterPenryn CampusPenrynCornwallTR109FEUK College of Forestry Hebei Agricultural UniversityBaoding071000China

Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and *** to natural factors such as climate and terrain,some tree species may form different forest patches at the edges of their distribution ***,how forest patches of various sizes respond to climate change is *** this study,we collected 203 tree cores from six different sizes of forest patches at the edge of the distribution area of Picea crassifolia *** the northeast Tibetan *** we used the dendrochronology method to study the response of tree growth and resilience in different forest patches to climate change from 1961 to *** simultaneously measured the contents of nonstructural carbohydrates(NSC),total nitrogen and total phosphorus of tree *** results showed that the growth of trees in small-and medium-size forest patches(0.8–18.6 ha)has increased *** early growing season(May–July)minimum temperature was the most important climate factor driving the growth of small-and medium-sized patch *** early growing season maximum temperature was the most important climate factor that inhibited the growth of trees in the largest patches(362.8 ha).The growth of individual trees in medium forest patches was better and the correlation with annual minimum temperature,maximum temperature,precipitation,actual evapotranspiration,and palmer drought severity index was *** higher NSC content,stronger photosynthesis,and higher nitrogen utilization efficiency in leaves might be one of the reasons for the better growth of trees in moderate forest *** extreme drought years,as the forest patch area increased,the overall trend of tree growth resistance showed a unimodal pattern,with the highest at a forest patch area of 7.1 ha,while the overall trend of tree growth recovery was ***,we should strengthen the management of trees in large

关键词： Climate change Picea crassifolia Kom Forest patches Tree growth Resilience

Senescence-specific Alteration of Hydrogen Peroxide Levels in Arabidopsis thaliana and Oilseed Rape Spring Variety Brassica napus ***

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Journal of Integrative Plant Biology 2012年第8期54卷 540-554页

作者： Stefan Bieker Lena Riester Mark Stahl Jürgen Franzaring Ulrike Zentgraf ZMBP (Center for Plant Molecular Biology) University of TübingenAuf der Morgenstelle 2872076 Tübingen Germany institute for landscape and Plant ecology kologiezentrum 2August-von-Hartmann-Str.370599 StuttgartGermany

In order to analyze the signaling function of hydrogen peroxide （H202） production in senescence in more detail, we manipulated intracellular H202 levels in Arabidopsis thaliala （L.） Heynh by using the hydrogen- peroxide-sensitive part of the Escherichia coil transcription regulator OxyR, which was directed to the cytoplasm as well as into the peroxisomes. H202 levels were lowered and senescence was delayed in both transgenic lines, but OxyR was found to be more effective in the cytoplasm. To transfer this knowledge to crop plants, we analyzed oilseed rape plants Brassica napus L. cv. Mozart for H20~ and its scavenging enzymes catalase （CAT） and ascorbate peroxidase （APX） during leaf and plant development. H202 levels were found to increase during bolting and flowering time, but no increase could be observed in the very late stages of senescence. With increasing H202 levels, CAT and APX activities declined, so it is likely that similar mechanisms are used in oilseed rape and Arabidopsis to control H202 levels. Under elevated CO2 conditions, oilseed rape senescence was accelerated and coincided with an earlier increase in H202 levels, indicating that H202 may be one of the signals to inducing senescence in a broader range of Brassicaceae.

关键词： Arabidopsis thaliana Brassica napus E. coil Oxy-RD intracellular hydrogen peroxide senescence phenotype catalase ascorbatePeroxidase elevated CO2.