@article{DiGiacomoDiGiacomoKligeretal.2015, author = {Di Giacomo, Adrian S. and Di Giacomo, Alejandro G. and Kliger, Rafi and Reboreda, Juan C. and Tiedemann, Ralph and Mahler, Bettina}, title = {No evidence of genetic variation in microsatellite and mitochondrial DNA markers among remaining populations of the Strange-tailed Tyrant Alectrurus risora, an endangered grassland species}, series = {Bird conservation international}, volume = {25}, journal = {Bird conservation international}, number = {2}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {0959-2709}, doi = {10.1017/S0959270914000203}, pages = {127 -- 138}, year = {2015}, abstract = {The Strange-tailed Tyrant Alectrurus risora (Aves: Tyrannidae) is an endemic species of southern South American grasslands that suffered a 90\% reduction of its original distribution due to habitat transformation. This has led the species to be classified as globally Vulnerable. By the beginning of the last century, populations were partially migratory and moved south during the breeding season. Currently, the main breeding population inhabits the Ibera wetlands in the province of Corrientes, north-east Argentina, where it is resident all year round. There are two remaining small populations in the province of Formosa, north-east Argentina, and in southern Paraguay, which are separated from the main population by the Parana-Paraguay River and its continuous riverine forest habitat. The populations of Corrientes and Formosa are separated by 300 km and the grasslands between populations are non-continuous due to habitat transformation. We used mtDNA sequences and eight microsatellite loci to test if there were evidences of genetic isolation between Argentinean populations. We found no evidence of genetic structure between populations (Phi(ST) = 0.004, P = 0.32; Fst = 0.01, P = 0.06), which can be explained by either retained ancestral polymorphism or by dispersal between populations. We found no evidence for a recent demographic bottleneck in nuclear loci. Our results indicate that these populations could be managed as a single conservation unit on a regional scale. Conservation actions should be focused on preserving the remaining network of areas with natural grasslands to guarantee reproduction, dispersal and prevent further decline of populations.}, language = {en} } @article{MuinodeBruijnPajoroetal.2015, author = {Mui{\~n}o, Jose M. and de Bruijn, Suzanne and Pajoro, Alice and Geuten, Koen and Vingron, Martin and Angenent, Gerco C. and Kaufmann, Kerstin}, title = {Evolution of DNA-Binding Sites of a Floral Master Regulatory Transcription Factor}, series = {Molecular biology and evolution : MBE}, volume = {33}, journal = {Molecular biology and evolution : MBE}, number = {1}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1537-1719}, doi = {10.1093/molbev/msv210}, year = {2015}, abstract = {lower development is controlled by the action of key regulatory transcription factors of the MADS-domain family. The function of these factors appears to be highly conserved among species based on mutant phenotypes. However, the conservation of their downstream processes is much less well understood, mostly because the evolutionary turnover and variation of their DNA-binding sites (BSs) among plant species have not yet been experimentally determined. Here, we performed comparative ChIP (chromatin immunoprecipitation)-seq experiments of the MADS-domain transcription factor SEPALLATA3 (SEP3) in two closely related Arabidopsis species: Arabidopsis thaliana and A. lyrata which have very similar floral organ morphology. We found that BS conservation is associated with DNA sequence conservation, the presence of the CArG-box BS motif and on the relative position of the BS to its potential target gene. Differences in genome size and structure can explain that SEP3 BSs in A. lyrata can be located more distantly to their potential target genes than their counterparts in A. thaliana. In A. lyrata, we identified transposition as a mechanism to generate novel SEP3 binding locations in the genome. Comparative gene expression analysis shows that the loss/gain of BSs is associated with a change in gene expression. In summary, this study investigates the evolutionary dynamics of DNA BSs of a floral key-regulatory transcription factor and explores factors affecting this phenomenon.}, language = {en} } @misc{MuinodeBruijnPajoroetal.2015, author = {Mui{\~n}o, Jose M. and de Bruijn, Suzanne and Pajoro, Alice and Geuten, Koen and Vingron, Martin and Angenent, Gerco C. and Kaufmann, Kerstin}, title = {Evolution of DNA-Binding Sites of a Floral Master Regulatory Transcription Factor}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-96580}, pages = {1225 -- 1245}, year = {2015}, abstract = {Flower development is controlled by the action of key regulatory transcription factors of the MADS-domain family. The function of these factors appears to be highly conserved among species based on mutant phenotypes. However, the conservation of their downstream processes is much less well understood, mostly because the evolutionary turnover and variation of their DNA-binding sites (BSs) among plant species have not yet been experimentally determined. Here, we performed comparative ChIP (chromatin immunoprecipitation)-seq experiments of the MADS-domain transcription factor SEPALLATA3 (SEP3) in two closely related Arabidopsis species: Arabidopsis thaliana and A. lyrata which have very similar floral organ morphology. We found that BS conservation is associated with DNA sequence conservation, the presence of the CArG-box BS motif and on the relative position of the BS to its potential target gene. Differences in genome size and structure can explain that SEP3 BSs in A. lyrata can be located more distantly to their potential target genes than their counterparts in A. thaliana. In A. lyrata, we identified transposition as a mechanism to generate novel SEP3 binding locations in the genome. Comparative gene expression analysis shows that the loss/gain of BSs is associated with a change in gene expression. In summary, this study investigates the evolutionary dynamics of DNA BSs of a floral key-regulatory transcription factor and explores factors affecting this phenomenon.}, language = {en} } @article{HornHempelRistowetal.2015, author = {Horn, Sebastian and Hempel, Stefan and Ristow, Michael and Rillig, Matthias C. and Kowarik, Ingo and Caruso, Tancredi}, title = {Plant community assembly at small scales: Spatial vs. environmental factors in a European grassland}, series = {Acta oecologica : international journal of ecology}, volume = {63}, journal = {Acta oecologica : international journal of ecology}, publisher = {Elsevier}, address = {Paris}, issn = {1146-609X}, doi = {10.1016/j.actao.2015.01.004}, pages = {56 -- 62}, year = {2015}, abstract = {Dispersal limitation and environmental conditions are crucial drivers of plant species distribution and establishment. As these factors operate at different spatial scales, we asked: Do the environmental factors known to determine community assembly at broad scales operate at fine scales (few meters)? How much do these factors account for community variation at fine scales? In which way do biotic and abiotic interactions drive changes in species composition? We surveyed the plant community within a dry grassland along a very steep gradient of soil characteristics like pH and nutrients. We used a spatially explicit sampling design, based on three replicated macroplots of 15 x 15, 12 x 12 and 12 x 12 m in extent. Soil samples were taken to quantify several soil properties (carbon, nitrogen, plant available phosphorus, pH, water content and dehydrogenase activity as a proxy for overall microbial activity). We performed variance partitioning to assess the effect of these variables on plant composition and statistically controlled for spatial autocorrelation via eigenvector mapping. We also applied null model analysis to test for non-random patterns in species co-occurrence using randomization schemes that account for patterns expected under species interactions. At a fine spatial scale, environmental factors explained 18\% of variation when controlling for spatial autocorrelation in the distribution of plant species, whereas purely spatial processes accounted for 14\% variation. Null model analysis showed that species spatially segregated in a non-random way and these spatial patterns could be due to a combination of environmental filtering and biotic interactions. Our grassland study suggests that environmental factors found to be directly relevant in broad scale studies are present also at small scales, but are supplemented by spatial processes and more direct interactions like competition. (C) 2015 Elsevier Masson SAS. All rights reserved.}, language = {en} } @inproceedings{LachmannSpijkermanMaberly2015, author = {Lachmann, Sabrina C. and Spijkerman, Elly and Maberly, Stephen C.}, title = {Ecology matters: linking inorganic carbon acquisition to ecological preference in four species of microalgae (Chlorophyceae)}, series = {European journal of phycology}, volume = {50}, booktitle = {European journal of phycology}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {0967-0262}, pages = {98 -- 98}, year = {2015}, language = {en} } @article{AllhoffRitterskampRalletal.2015, author = {Allhoff, Korinna Theresa and Ritterskamp, Daniel and Rall, Bj{\"o}rn C. and Drossel, Barbara and Guill, Christian}, title = {Evolutionary food web model based on body masses gives realistic networks with permanent species turnover}, series = {Scientific reports}, volume = {5}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/srep10955}, pages = {12}, year = {2015}, abstract = {The networks of predator-prey interactions in ecological systems are remarkably complex, but nevertheless surprisingly stable in terms of long term persistence of the system as a whole. In order to understand the mechanism driving the complexity and stability of such food webs, we developed an eco-evolutionary model in which new species emerge as modifications of existing ones and dynamic ecological interactions determine which species are viable. The food-web structure thereby emerges from the dynamical interplay between speciation and trophic interactions. The proposed model is less abstract than earlier evolutionary food web models in the sense that all three evolving traits have a clear biological meaning, namely the average body mass of the individuals, the preferred prey body mass, and the width of their potential prey body mass spectrum. We observed networks with a wide range of sizes and structures and high similarity to natural food webs. The model networks exhibit a continuous species turnover, but massive extinction waves that affect more than 50\% of the network are not observed.}, language = {en} } @article{HeinzeWernerWeberetal.2015, author = {Heinze, Johannes and Werner, Tony and Weber, Ewald and Rillig, Matthias C. and Joshi, Jasmin Radha}, title = {Soil biota effects on local abundances of three grass species along a land-use gradient}, series = {Oecologia}, volume = {179}, journal = {Oecologia}, number = {1}, publisher = {Springer}, address = {New York}, issn = {0029-8549}, doi = {10.1007/s00442-015-3336-0}, pages = {249 -- 259}, year = {2015}, abstract = {Biotic plant-soil interactions and land-use intensity are known to affect plant individual fitness as well as competitiveness and therefore plant-species abundances in communities. Therefore, a link between soil biota and land-use intensity on local abundance of plant species in grasslands can be expected. In two greenhouse experiments, we investigated the effects of soil biota from grassland sites differing in land-use intensity on three grass species that vary in local abundances along this land-use gradient. We were interested in those soil-biota effects that are associated with land-use intensity, and whether these effects act directly or indirectly. Therefore, we grew the three plant species in two separate experiments as single individuals and in mixtures and compared their performance. As single plants, all three grasses showed a similar performance with and without soil biota. In contrast, in mixtures growth of the species in response to the presence or absence of soil biota differed. This resulted in different soil-biota effects that tend to correspond with patterns of species-specific abundances in the field for two of the three species tested. Our results highlight the importance of indirect interactions between plants and soil microorganisms and suggest that combined effects of soil biota and plant-plant interactions are involved in structuring plant communities. In conclusion, our experiments suggest that soil biota may have the potential to alter effects of plant-plant interactions and therefore influence plant-species abundances and diversity in grasslands.}, language = {en} } @article{AllanManningAltetal.2015, author = {Allan, Eric and Manning, Pete and Alt, Fabian and Binkenstein, Julia and Blaser, Stefan and Bl{\"u}thgen, Nico and B{\"o}hm, Stefan and Grassein, Fabrice and H{\"o}lzel, Norbert and Klaus, Valentin H. and Kleinebecker, Till and Morris, E. Kathryn and Oelmann, Yvonne and Prati, Daniel and Renner, Swen C. and Rillig, Matthias C. and Schaefer, Martin and Schloter, Michael and Schmitt, Barbara and Sch{\"o}ning, Ingo and Schrumpf, Marion and Solly, Emily and Sorkau, Elisabeth and Steckel, Juliane and Steffen-Dewenter, Ingolf and Stempfhuber, Barbara and Tschapka, Marco and Weiner, Christiane N. and Weisser, Wolfgang W. and Werner, Michael and Westphal, Catrin and Wilcke, Wolfgang and Fischer, Markus}, title = {Land use intensification alters ecosystem multifunctionality via loss of biodiversity and changes to functional composition}, series = {Ecology letters}, volume = {18}, journal = {Ecology letters}, number = {8}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1461-023X}, doi = {10.1111/ele.12469}, pages = {834 -- 843}, year = {2015}, abstract = {Global change, especially land-use intensification, affects human well-being by impacting the delivery of multiple ecosystem services (multifunctionality). However, whether biodiversity loss is a major component of global change effects on multifunctionality in real-world ecosystems, as in experimental ones, remains unclear. Therefore, we assessed biodiversity, functional composition and 14 ecosystem services on 150 agricultural grasslands differing in land-use intensity. We also introduce five multifunctionality measures in which ecosystem services were weighted according to realistic land-use objectives. We found that indirect land-use effects, i.e. those mediated by biodiversity loss and by changes to functional composition, were as strong as direct effects on average. Their strength varied with land-use objectives and regional context. Biodiversity loss explained indirect effects in a region of intermediate productivity and was most damaging when land-use objectives favoured supporting and cultural services. In contrast, functional composition shifts, towards fast-growing plant species, strongly increased provisioning services in more inherently unproductive grasslands.}, language = {en} } @article{StanislasHuserBarbosaetal.2015, author = {Stanislas, Thomas and Huser, Anke and Barbosa, Ines C. R. and Kiefer, Christian S. and Brackmann, Klaus and Pietra, Stefano and Gustavsson, Anna and Zourelidou, Melina and Schwechheimer, Claus and Grebe, Markus}, title = {Arabidopsis D6PK is a lipid domain-dependent mediator of root epidermal planar polarity}, series = {Nature plants}, volume = {1}, journal = {Nature plants}, number = {11}, publisher = {Nature Publ. Group}, address = {London}, issn = {2055-026X}, doi = {10.1038/NPLANTS.2015.162}, pages = {9}, year = {2015}, abstract = {Development of diverse multicellular organisms relies on coordination of single-cell polarities within the plane of the tissue layer (planar polarity). Cell polarity often involves plasma membrane heterogeneity generated by accumulation of specific lipids and proteins into membrane subdomains. Coordinated hair positioning along Arabidopsis root epidermal cells provides a planar polarity model in plants, but knowledge about the functions of proteo-lipid domains in planar polarity signalling remains limited. Here we show that Rho-of-plant (ROP) 2 and 6, phosphatidylinositol-4-phosphate 5-kinase 3 (PIP5K3), DYNAMIN-RELATED PROTEIN (DRP) 1A and DRP2B accumulate in a sterol-enriched, polar membrane domain during root hair initiation. DRP1A, DRP2B, PIP5K3 and sterols are required for planar polarity and the AGCVIII kinase D6 PROTEIN KINASE (D6PK) is a modulator of this process. D6PK undergoes phosphatidylinositol-4,5-bisphosphate- and sterol-dependent basal-to-planar polarity switching into the polar, lipid-enriched domain just before hair formation, unravelling lipid-dependent D6PK localization during late planar polarity signalling.}, language = {en} } @article{AlterMeyerPostetal.2015, author = {Alter, S. Elizabeth and Meyer, Matthias and Post, Klaas and Czechowski, Paul and Gravlund, Peter and Gaines, Cork and Rosenbaum, Howard C. and Kaschner, Kristin and Turvey, Samuel T. and van der Plicht, Johannes and Shapiro, Beth and Hofreiter, Michael}, title = {Climate impacts on transocean dispersal and habitat in gray whales from the Pleistocene to 2100}, series = {Molecular ecology}, volume = {24}, journal = {Molecular ecology}, number = {7}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0962-1083}, doi = {10.1111/mec.13121}, pages = {1510 -- 1522}, year = {2015}, abstract = {Arctic animals face dramatic habitat alteration due to ongoing climate change. Understanding how such species have responded to past glacial cycles can help us forecast their response to today's changing climate. Gray whales are among those marine species likely to be strongly affected by Arctic climate change, but a thorough analysis of past climate impacts on this species has been complicated by lack of information about an extinct population in the Atlantic. While little is known about the history of Atlantic gray whales or their relationship to the extant Pacific population, the extirpation of the Atlantic population during historical times has been attributed to whaling. We used a combination of ancient and modern DNA, radiocarbon dating and predictive habitat modelling to better understand the distribution of gray whales during the Pleistocene and Holocene. Our results reveal that dispersal between the Pacific and Atlantic was climate dependent and occurred both during the Pleistocene prior to the last glacial period and the early Holocene immediately following the opening of the Bering Strait. Genetic diversity in the Atlantic declined over an extended interval that predates the period of intensive commercial whaling, indicating this decline may have been precipitated by Holocene climate or other ecological causes. These first genetic data for Atlantic gray whales, particularly when combined with predictive habitat models for the year 2100, suggest that two recent sightings of gray whales in the Atlantic may represent the beginning of the expansion of this species' habitat beyond its currently realized range.}, language = {en} } @article{TeasdalevanDoornFiddymentetal.2015, author = {Teasdale, Matthew David and van Doorn, N. L. and Fiddyment, S. and Webb, C. C. and Hofreiter, Michael and Collins, Matthew J. and Bradley, Daniel G.}, title = {Paging through history: parchment as a reservoir of ancient DNA for next generation sequencing}, series = {Philosophical transactions of the Royal Society of London : B, Biological sciences}, volume = {370}, journal = {Philosophical transactions of the Royal Society of London : B, Biological sciences}, number = {1660}, publisher = {Royal Society}, address = {London}, issn = {0962-8436}, doi = {10.1098/rstb.2013.0379}, pages = {7}, year = {2015}, abstract = {Parchment represents an invaluable cultural reservoir. Retrieving an additional layer of information from these abundant, dated livestock-skins via the use of ancient DNA (aDNA) sequencing has been mooted by a number of researchers. However, prior PCR-based work has indicated that this may be challenged by cross-individual and cross-species contamination, perhaps from the bulk parchment preparation process. Here we apply next generation sequencing to two parchments of seventeenth and eighteenth century northern English provenance. Following alignment to the published sheep, goat, cow and human genomes, it is clear that the only genome displaying substantial unique homology is sheep and this species identification is confirmed by collagen peptide mass spectrometry. Only 4\% of sequence reads align preferentially to a different species indicating low contamination across species. Moreover, mitochondrial DNA sequences suggest an upper bound of contamination at 5\%. Over 45\% of reads aligned to the sheep genome, and even this limited sequencing exercise yield 9 and 7\% of each sampled sheep genome post filtering, allowing the mapping of genetic affinity to modern British sheep breeds. We conclude that parchment represents an excellent substrate for genomic analyses of historical livestock.}, language = {en} } @misc{WarrenSimberloffRicklefsetal.2015, author = {Warren, Ben H. and Simberloff, Daniel and Ricklefs, Robert E. and Aguilee, Robin and Condamine, Fabien L. and Gravel, Dominique and Morlon, Helene and Mouquet, Nicolas and Rosindell, James and Casquet, Juliane and Conti, Elena and Cornuault, Josselin and Maria Fernandez-Palacios, Jose and Hengl, Tomislav and Norder, Sietze J. and Rijsdijk, Kenneth F. and Sanmartin, Isabel and Strasberg, Dominique and Triantis, Kostas A. and Valente, Luis M. and Whittaker, Robert J. and Gillespie, Rosemary G. and Emerson, Brent C. and Thebaud, Christophe}, title = {Islands as model systems in ecology and evolution: prospects fifty years after MacArthur-Wilson}, series = {Ecology letters}, volume = {18}, journal = {Ecology letters}, number = {2}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1461-023X}, doi = {10.1111/ele.12398}, pages = {200 -- 217}, year = {2015}, abstract = {The study of islands as model systems has played an important role in the development of evolutionary and ecological theory. The 50th anniversary of MacArthur and Wilson's (December 1963) article, An equilibrium theory of insular zoogeography', was a recent milestone for this theme. Since 1963, island systems have provided new insights into the formation of ecological communities. Here, building on such developments, we highlight prospects for research on islands to improve our understanding of the ecology and evolution of communities in general. Throughout, we emphasise how attributes of islands combine to provide unusual research opportunities, the implications of which stretch far beyond islands. Molecular tools and increasing data acquisition now permit re-assessment of some fundamental issues that interested MacArthur and Wilson. These include the formation of ecological networks, species abundance distributions, and the contribution of evolution to community assembly. We also extend our prospects to other fields of ecology and evolution - understanding ecosystem functioning, speciation and diversification - frequently employing assets of oceanic islands in inferring the geographic area within which evolution has occurred, and potential barriers to gene flow. Although island-based theory is continually being enriched, incorporating non-equilibrium dynamics is identified as a major challenge for the future.}, language = {en} } @article{MakowerSchuurmansGrothetal.2015, author = {Makower, A. Katharina and Schuurmans, J. Merijn and Groth, Detlef and Zilliges, Yvonne and Matthijs, Hans C. P. and Dittmann-Th{\"u}nemann, Elke}, title = {Transcriptomics-Aided dissection of the intracellular and extracellular roles of microcystin in microcystis aeruginosa PCC 7806}, series = {Applied and environmental microbiology}, volume = {81}, journal = {Applied and environmental microbiology}, number = {2}, publisher = {American Society for Microbiology}, address = {Washington}, issn = {0099-2240}, doi = {10.1128/AEM.02601-14}, pages = {544 -- 554}, year = {2015}, abstract = {Recent studies have provided evidence for both intracellular and extracellular roles of the potent hepatotoxin microcystin (MC) in the bloom-forming cyanobacterium Microcystis. Here, we surveyed transcriptomes of the wild-type strain M. aeruginosa PCC 7806 and the microcystin-deficient Delta mcyB mutant under low light conditions with and without the addition of external MC of the LR variant (MC-LR). Transcriptomic data acquired by microarray and quantitative PCR revealed substantial differences in the relative expression of genes of the central intermediary metabolism, photosynthesis, and energy metabolism. In particular, the data provide evidence for a lower photosystem I (PSI)-to-photosystem II (PSII) ratio and a more pronounced carbon limitation in the microcystin-deficient mutant. Interestingly, only 6\% of the transcriptional differences could be complemented by external microcystin-LR addition. This MC signaling effect was seen exclusively for genes of the secondary metabolism category. The orphan polyketide synthase gene cluster IPF38-51 was specifically downregulated in response to external MC-LR under low light. Our data suggest a hierarchical and light-dependent cross talk of secondary metabolites and support both an intracellular and an extracellular role of MC in Microcystis.}, language = {en} } @article{SchopperMuhlenbockSorenssonetal.2015, author = {Schopper, S. and Muhlenbock, P. and Sorensson, C. and Hellborg, L. and Lenman, M. and Widell, S. and Fettke, J{\"o}rg and Andreasson, Erik}, title = {Arabidopsis cytosolic alpha-glycan phosphorylase, PHS2, is important during carbohydrate imbalanced conditions}, series = {Plant biology}, volume = {17}, journal = {Plant biology}, number = {1}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1435-8603}, doi = {10.1111/plb.12190}, pages = {74 -- 80}, year = {2015}, abstract = {Arabidopsis thaliana has two isoforms of alpha-glycan phosphorylase (EC 2.4.1.1), one residing in the plastid and the other in the cytosol. The cytosolic phosphorylase, PHS2, acts on soluble heteroglycans that constitute a part of the carbohydrate pool in a plant. This study aimed to define a physiological role for PHS2. Under standard growth conditions phs2 knock-out mutants do not show any clear growth phenotype, and we hypothesised that during low-light conditions where carbohydrate imbalance is perturbed, this enzyme is important. Soil-grown phs2 mutant plants developed leaf lesions when placed in very low light. Analysis of soluble heteroglycan (SHG) levels showed that the amount of glucose residues in SHG was higher in the phs2 mutant compared to wild-type plants. Furthermore, a standard senescence assay from soil-grown phs2 mutant plants showed that leaves senesced significantly faster in darkness than the wild-type leaves. We also found decreased hypocotyl extension in in vitro-grown phs2 mutant seedlings when grown for long time in darkness at 6 degrees C. We conclude that PHS2 activity is important in the adult stage during low-light conditions and senescence, as well as during prolonged seedling development when carbohydrate levels are unbalanced.}, language = {en} } @article{HeinzeBergmannRilligetal.2015, author = {Heinze, Johannes and Bergmann, Joana and Rillig, Matthias C. and Joshi, Jasmin Radha}, title = {Negative biotic soil-effects enhance biodiversity by restricting potentially dominant plant species in grasslands}, series = {Perspectives in plant ecology, evolution and systematics}, volume = {17}, journal = {Perspectives in plant ecology, evolution and systematics}, number = {3}, publisher = {Elsevier}, address = {Jena}, issn = {1433-8319}, doi = {10.1016/j.ppees.2015.03.002}, pages = {227 -- 235}, year = {2015}, abstract = {Interactions between soil microorganisms and plants can play a vital role for plant fitness and therefore also for plant community composition and biodiversity. However, little is known about how biotic plant soil interactions influence the local dominance and abundance of plant species and whether specific taxonomic or functional groups of plants are differentially affected by such biotic soil-effects. In two greenhouse experiments, we tested the biotic soil-effects of 33 grassland species differing in individual size and local abundance. We hypothesized that large plants that are not locally dominant (despite their size-related competitive advantage enabling them to potentially outshade competitors) are most strongly limited by negative biotic soil-effects. We sampled soils at the opposite ends of a gradient in land-use intensity in temperate grasslands to account for putative modulating effects of land-use intensity on biotic soil-effects. As hypothesized, large, but non-dominant species (especially grasses) experienced more negative biotic soil-effects compared with small and abundant plant species. Land-use intensity had contrasting effects on grasses and herbs resulting in more negative biotic soil-effects for grasses in less intensively managed grasslands. We conclude that biotic soil-effects contribute to the control of potentially dominant plants and hence enable species coexistence and biodiversity especially in species-rich less intensively managed grasslands.}, language = {en} } @article{GuhaWarsinkeTientcheuetal.2015, author = {Guha, S. and Warsinke, Axel and Tientcheu, Charles Merlin and Schmalz, K. and Meliani, C. and Wenger, Ch.}, title = {Label free sensing of creatinine using a 6 GHz CMOS near-field dielectric immunosensor}, series = {The analyst : the analytical journal of the Royal Society of Chemistry}, volume = {140}, journal = {The analyst : the analytical journal of the Royal Society of Chemistry}, number = {9}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {0003-2654}, doi = {10.1039/c4an02194k}, pages = {3019 -- 3027}, year = {2015}, abstract = {In this work we present a CMOS high frequency direct immunosensor operating at 6 GHz (C-band) for label free determination of creatinine. The sensor is fabricated in standard 0.13 mu m SiGe:C BiCMOS process. The report also demonstrates the ability to immobilize creatinine molecules on a Si3N4 passivation layer of the standard BiCMOS/CMOS process, therefore, evading any further need of cumbersome post processing of the fabricated sensor chip. The sensor is based on capacitive detection of the amount of non-creatinine bound antibodies binding to an immobilized creatinine layer on the passivated sensor. The chip bound antibody amount in turn corresponds indirectly to the creatinine concentration used in the incubation phase. The determination of creatinine in the concentration range of 0.88-880 mu M is successfully demonstrated in this work. A sensitivity of 35 MHz/10 fold increase in creatinine concentration (during incubation) at the centre frequency of 6 GHz is gained by the immunosensor. The results are compared with a standard optical measurement technique and the dynamic range and sensitivity is of the order of the established optical indication technique. The C-band immunosensor chip comprising an area of 0.3 mm(2) reduces the sensing area considerably, therefore, requiring a sample volume as low as 2 mu l. The small analyte sample volume and label free approach also reduce the experimental costs in addition to the low fabrication costs offered by the batch fabrication technique of CMOS/BiCMOS process.}, language = {en} } @article{ThieleGrimm2015, author = {Thiele, Jan C. and Grimm, Volker}, title = {Replicating and breaking models: good for you and good for ecology}, series = {Oikos}, volume = {124}, journal = {Oikos}, number = {6}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0030-1299}, doi = {10.1111/oik.02170}, pages = {691 -- 696}, year = {2015}, abstract = {There are two major limitations to the potential of computational models in ecology for producing general insights: their design is path-dependent, reflecting different underlying questions, assumptions, and data, and there is too little robustness analysis exploring where the model mechanisms explaining certain observations break down. We here argue that both limitations could be overcome if modellers in ecology would more often replicate existing models, try to break the models, and explore modifications. Replication comprises the re-implementation of an existing model and the replication of its results. Breaking models means to identify under what conditions the mechanisms represented in a model can no longer explain observed phenomena. The benefits of replication include less effort being spent to enter the iterative stage of model development and having more time for systematic robustness analysis. A culture of replication would lead to increased credibility, coherence and efficiency of computational modelling and thereby facilitate theory development.}, language = {en} } @article{ManningGossnerBossdorfetal.2015, author = {Manning, Pete and Gossner, Martin M. and Bossdorf, Oliver and Allan, Eric and Zhang, Yuan-Ye and Prati, Daniel and Bl{\"u}thgen, Nico and Boch, Steffen and B{\"o}hm, Stefan and B{\"o}rschig, Carmen and H{\"o}lzel, Norbert and Jung, Kirsten and Klaus, Valentin H. and Klein, Alexandra-Maria and Kleinebecker, Till and Krauss, Jochen and Lange, Markus and M{\"u}ller, J{\"o}rg and Pasalic, Esther and Socher, Stephanie A. and Tschapka, Marco and T{\"u}rke, Manfred and Weiner, Christiane and Werner, Michael and Gockel, Sonja and Hemp, Andreas and Renner, Swen C. and Wells, Konstans and Buscot, Francois and Kalko, Elisabeth K. V. and Linsenmair, Karl Eduard and Weisser, Wolfgang W. and Fischer, Markus}, title = {Grassland management intensification weakens the associations among the diversities of multiple plant and animal taxa}, series = {Ecology : a publication of the Ecological Society of America}, volume = {96}, journal = {Ecology : a publication of the Ecological Society of America}, number = {6}, publisher = {Wiley}, address = {Washington}, issn = {0012-9658}, doi = {10.1890/14-1307.1}, pages = {1492 -- 1501}, year = {2015}, abstract = {Land-use intensification is a key driver of biodiversity change. However, little is known about how it alters relationships between the diversities of different taxonomic groups, which are often correlated due to shared environmental drivers and trophic interactions. Using data from 150 grassland sites, we examined how land-use intensification (increased fertilization, higher livestock densities, and increased mowing frequency) altered correlations between the species richness of 15 plant, invertebrate, and vertebrate taxa. We found that 54\% of pairwise correlations between taxonomic groups were significant and positive among all grasslands, while only one was negative. Higher land-use intensity substantially weakened these correlations(35\% decrease in rand 43\% fewer significant pairwise correlations at high intensity), a pattern which may emerge as a result of biodiversity declines and the breakdown of specialized relationships in these conditions. Nevertheless, some groups (Coleoptera, Heteroptera, Hymenoptera and Orthoptera) were consistently correlated with multidiversity, an aggregate measure of total biodiversity comprised of the standardized diversities of multiple taxa, at both high and lowland-use intensity. The form of intensification was also important; increased fertilization and mowing frequency typically weakened plant-plant and plant-primary consumer correlations, whereas grazing intensification did not. This may reflect decreased habitat heterogeneity under mowing and fertilization and increased habitat heterogeneity under grazing. While these results urge caution in using certain taxonomic groups to monitor impacts of agricultural management on biodiversity, they also suggest that the diversities of some groups are reasonably robust indicators of total biodiversity across a range of conditions.}, language = {en} }