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Effects of grassland management, endophytic fungi and predators on aphid abundance in two distinct regions

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Journal of Plant ecology 2014年第5期7卷 490-498页

作者： Carmen Börschig Alexandra-M.Klein Jochen Krauss Agroecology Department of Crop SciencesUniversity of GöttingenGrisebachstrasse 6D-37075 GöttingenGermany Ecosystem Functions Institute of EcologyUniversity of LüneburgScharnhorstrasse 1D-21335 LüneburgGermany Nature conservation and Landscape ecology Institute of Earth and Environmental SciencesUniversity of FreiburgTennenbacherstr.4D-79106 FreiburgGermany Department of Animal ecology and Tropical Biology University of WürzburgBiocentreAm HublandD-97074 WürzburgGermany

Aims Fungal endophytes of cool-season grass species produce alkaloids toxic to herbivores,affecting food webs in agricultural and natural *** studies about the effects of endophytes on herbi-vores are rare and show contradictory results,leading to uncertain conclusions about the nature of endophyte-grass *** asked whether the environmental contexts of local and regional scales and predation could modify the effects of endophytes on *** In a full factorial field experiment,we quantified the abundance of the aphid species Rhopalosiphum padi on the potted host grass Lolium perenne,which was either infected or uninfected with the endophytic fungus Neotyphodium *** were either excluded or had free access to the pots with the *** hun-dred and sixty grass pots were located in two regions on altogether 40 grassland sites,half of the sites intensively and half extensively *** tested the importance of endophyte infection,study region,management intensity of grasslands,predation and all two-way interactions on aphid *** Findings Endophyte infection reduced aphid abundance significantly in one study region *** both regions,we found that the impacts of aphidophagous predators and grassland management intensity on aphid abundance were substantially stronger and more consistent than that of endophytes on aphid *** excluding preda-tors and pots placed on extensive grasslands contained higher aphid *** impact of predators and management on aphid abundance were not modified by the *** conclude that the effect of endophytes on herbivores can be weak in field experi-ments and depends on environmental context at a regional ***,more field research efforts are necessary to detect the rela-tive importance of endophytes and the environmental context on biotic interactions in ecosystems.

关键词： bottom-up control microorganism multi-trophic interaction predator exclosure top-down control

Exotic plant species with longer seed bank longevity and lower seed dry mass are more likely to be invasive in China

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Journal of Plant ecology 2024年第5期17卷 106-119页

作者： Yueyan Pan Lumeng Xie Ruiyan Shang Bernard AEngel Jingqiu Chen Shijun Zhou Yi Li Mingxiang Zhang Zhenming Zhang Jiakai Liu School of ecology and Nature conservation Beijing Forestry UniversityBeijing 100083China The Key Laboratory of Ecological Protection in the Yellow River Basin of National Forestry and Grassland Administration Beijing 100083China College of Agriculture Purdue UniversityWest LafayetteIN 47907USA Biological Systems Engineering Florida A&M UniversityTallahasseeFL 32310USA Wetland Research centre of Beijing Forestry University Beijing 100083China

Globalization of social and economic activities has led to the large-scale redistribution of plant *** is still unclear how the traits aid the successful invasion of alien ***,we downloaded global plant trait data from the TRY-Plant Trait Database and classified alien species in China into four groups:high,medium,need attention and harmless according to their distribution and degree of harm to local plant communities based on existed *** relationship between plant functional traits and invasion level was clarified,and we established a prediction model based on plant functional traits and *** results showed that species with smaller seeds,smaller individuals,lower special leaf area and longer seed bank longevity(SL)are more likely to be an invasive species after introduction to foreign *** summary,exotic species with longer SL and lower seed dry mass are more likely to be invasive in *** also trained two predictive models to check if we can predict a species’*** the two models together,statistically,we could predict if a species is invasive from its traits and taxonomy with a 91.84%*** model could help local governments,managers and stakeholders to evaluate shall we introduce some plant species in China.

关键词： exotic plant plant invasion plant traits invasion model seed bank

Redistribution of Soil Organic Carbon Triggered by Erosion at Field Scale Under Subhumid Climate,Hungary

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Pedosphere 2016年第5期26卷 652-665页

作者： Zoltan SZALAI Judit SZABO Jozsef KOVACS Erzsebet MESZAROS Gaspar ALBERT Csaba CENTERI Boglarka SZABO Balazs MADARASZ Dora ZACHARY Gergely JAKAB Geographical Institute Research centre for Astronomy and Earth Sciences Hungarian Academy of SciencesBudapest 1112(Hungary) Department of Environmental and Landscape Geography Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Applied and Environmental Geology Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Cartography and Geoinformatics Eotvos Lordnd UniversityBudapest 1117(Hungary) Department of Nature conservation and Landscape ecology Szent Istvdn UniversityGodollo 2100(Hungary)

Soil organic carbon(SOC) has primary importance in terms of soil physics, soil fertility and even of climate change control. One hundred soil samples were taken from an intensively cultivated Cambisol to quantify SOC redistribution triggered by soil erosion under a subhumid climate, by the simultaneous application of diffuse reflectance(240–1 900 nm) and traditional physico-chemical *** representative sample points were collected from the solum along the slopes at the depth of 20–300 cm with a mean SOC content of 12 g kg^(-1). Hierarchical cluster analyses were performed based on the determined SOC results. The spatial pattern of the groups created were similar, and even though the classifications were not the same, diffuse reflectance had proven to be a suitable method for soil/sediment classification even within a given arable field. Both organic and inorganic carbon distributions were found to be a proper tool for estimations of past soil erosion processes. The SOC enrichment was found on two sedimentary spots with different geomorphological positions. Soil organic matter composition also differed between the two spots due to selective deposition of the delivered organic matter. The components with low-molecular-weight reached the bottom of the slope where they could leach into the profile, while the more polymerised organic matter compositions were delivered and deposited even before on a higher segment of the slope in an aggregated form. This spatial difference appeared below the uppermost tilled soil layer as well, referring the lower efficiency of conventional ploughing tillage in soil spatial homogenisation.

关键词： Cambisol carbon sequestration diffuse reflectance selective erosion soil organic matter composition

Complex Effective Relative Permittivity of Soil Samples from the Taunus Region (Germany)

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Journal of Earth Science 2010年第6期21卷 961-967页

作者： Katja Lauer Christian Albrecht Christina Salat Peter Felix-Henningsen Institute of Soil Science and Soil conservation Research Centre for BioSystems Land Use and Nutrition (IFZ) Justus-Liebig-University Giessen Department of Underground Space for Storage and Economic Use Federal Institute for Geosciences and Natural Resources

The most important parameter affecting ground-penetrating radar （GPR） measurements is the complex effective relative permittivity εr^＊,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^＊,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^＊,eff= εr^＊,eff - jεr^＊,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^＊,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL （1980）, we find that Topp et aL＇s curve tends to underestimate the real part of εr^＊,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^＊,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^＊,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction.

关键词： ground-penetrating radar (GPR) complex effective relative permittivity soil sample.

Effects of twine material on the marine debris and relative ghost fishing of portunid hoop (tangle) nets

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Aquaculture and Fisheries 2020年第2期5卷 99-104页

作者： Matt K.Broadhurst Russell B.Millar NSW Department of Primary Industries Fisheries Conservation Technology UnitNational Marine Science CentreCoffs Harbour2450Australia Marine and Estuarine ecology Unit School of Biological SciencesUniversity of QueenslandBrisbane4072Australia Department of Statistics The University of AucklandPrivate Bag 92019Auckland1142New Zealand

Portunids are important to recreational fisheries in Australia and typically are harvested by baited *** of these baited gears are considered environmentally benign,although small conical hoop(tangle)nets fished in southeastern Australia sometimes are damaged and lose twine,which becomes marine *** conventional multifilament polyamide(PA)twine with alternative multi-monofilament and monofilament PA twines in hoop nets can dramatically reduce marine debris,but there remain unanswered questions concerning the relative fishing power of alternative twines among derelict hoop *** study addresses the shortfall in data by comparing the efficiencies and damage to replicate hoop nets made from the three twines and left to fish for short(one and two days),medium(three to five days)and long(ten and fourteen days)*** of twine material or soak time,all hoop nets entangled the same numbers of giant mud crabs,Scylla serrata implying catch saturation within two *** four other animals were caught(all yellowfin bream,Acanthopagrus australis)and all *** least some replicates of all hoop nets were damaged and lost twine,but this was greatest among the multifilament(up to a maximum of 9.3m hoop-net deployment−1),followed by the multi-monofilament(up to 7.4m hoop-net deployment−1)and monofilament hoop nets(1.4m hoop-net deployment−1).Replacing the existing multifilament twine in hoop nets with monofilament when targeting *** would maintain catches and minimise marine debris during conventional soaks,without increasing ghost fishing over the short term.

关键词： Bycatch Decapods Discard mortality Unaccounted fishing mortality

Water Security:Why We Need Global Solutions

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Engineering 2022年第9期16卷 13-15页

作者： Roger A.Falconer Hydro-environmental Research centre School of EngineeringCardiff UniversityCardiff CF243AAUK Yangtze Institute for conservation and Development Hohai UniversityNanjing 210024China

*** to the challenges of water security Over the past two to three decades,international concern about global water security has been increasing,along with a need for a more holistic approach to deliver sustainable solutions that address the growing challenges of water *** a series of high-profile reports have been published on global water security during this period(e.g.,Ref.[1]),the challenges remain and—if anything—are becoming more *** planet has limited freshwater resources:The total global volume of water is 1.4 billion km^(3),but only 35 million km^(3) of this resource is freshwater,and much of it is locked in the form of ***,only 105000 km^(3) of fresh water is accessible for use as water supply,and 70% of all withdrawals of freshwater are currently used for agriculture,primarily for food production[2].

关键词： planet extreme freshwater

Advances in herpetological research emanating from China

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Zoological Research 2016年第1期37卷 4-6页

作者： Robert W.MURPHY the State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Sciences and the centre for Biodiversity and conservation Biology,Royal Ontario Museum State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Centre for Biodiversity and Conservation Biology Royal Ontario Museum. bob.murphy@utoronto.ca.

The warming of Earth owing to human activities is resulting in an episode of mass extinction. If global warming is not abated quickly, up to one-fourth of the species on our planet will face extinction in only 35 years. The loss of biodiversity is more than just many species disappearing. It could signal the beginning of the collapse of our ecosystems because the loss of one species can trigger a domino effect. Among vertebrates, the so-called cold bloodied species--fishes, amphibians and reptiles--are the most threatened groups.

关键词： Advances in herpetological research emanating from China

Endangered lowland oak forest steppe remnants keep unique bird species richness in Central Hungary

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Journal of Forestry Research 2022年第1期33卷 343-355页

作者： GáborÓnodi Zoltán Botta‑Dukát Dániel Winkler Tamás Rédei Institute of ecology and Botany Centre for Ecological ResearchVácrátótHungary Department of Botany and Biodiversity Research University of ViennaViennaAustria Institute of Wildlife Management and Wildlife Biology University of SopronSopronHungary

The biodiversity of natural or semi-natural native,old oak woodlands have high conservation importance,especially in landscapes of monocultural forest plantations and arable *** a wider variety of microhabitats and foraging sources,such old oak forests can provide essential habitat for native forest bird *** conducted a study using bird point counts to compare the forest bird communities of old pedunculate oak(Quercus robur)remnants with native and non-native plantations in central Hungary in a landscape of mostly arable fields,settlements,and monocultural *** surveys were carried out in old oak forest remnants,middle-aged oak,white poplar(Populus alba),hybrid poplar(Populus×euramericana),black locust(Robinia pseudoacacia),and pine(Pinus spp.)*** has been carried out in nine study sites,where all six habitat types were represented(with a few exceptions),to determine total abundance,species richness,Shannon–Wiener diversity,species evenness,dominant and indicator species,and guild *** found that old oak forest remnants were the most diverse habitats among the studied forest types,while hybrid poplar and pine plantations exhibited the lowest avian *** avian guilds most sensitive to the loss of old oak forest remnants were ground foragers,bark foragers,cavity-nesters,residents,and Mediterranean migratory *** habitats were more diverse than non-native *** results suggest that it is important to conserve all remaining high biodiversity old oak stands and to avoid clear-cutting of monocultural plantations in favour of practices such as mixed-species plantations,longer rotation lengths,or retention forestry.

关键词： Forest bird community Bird conservation Old oak forest-steppe remnant Plantation forestry Forest conservation Non-native plantation

A phylogenetic approach identifies patterns of beta diversity and floristic subregions of the Qinghai-Tibet Plateau

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Plant Diversity 2024年第1期46卷 59-69页

作者： Haibin Yu Man Yang Zixin Lu Weitao Wang Fangyuan Yu Yonghua Zhang Xue Yin Hongjun Yu Junjie Hu David C.Deane Key Laboratory of conservation and Application in Biodiversity of South China School of Life SciencesGuangzhou UniversityGuangzhou 510006China School of ecology Sun Yat-Sen UniversityShenzhen 510275China School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China College of Life and Environmental Science Wenzhou UniversityWenzhou 325035China centre for Future Landscapes and Department of Environment and Genetics La Trobe UniversityBundooraVIC 3083Australia

Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional *** Qinghai-Tibet Plateau(QTP)harbors an exceptionally diverse flora,however,a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic *** this study,we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet *** also examined the relationships between multifaceted beta diversity,geographical distance,and climatic difference,and evaluated the relative importance of various factors(i.e.,climate,topography and history)in shaping patterns of beta diversity.Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the *** also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic *** environmental factors that contributed most to these patterns of beta diversity include annual precipitation,mean annual temperature,climatic gradients and climatic *** dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the *** results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP.

关键词： Biogeographical regionalization Phylogenetic beta diversity Seed plants Sørensen dissimilarity Qinghai-Tibet Plateau