Refine
Has Fulltext
- no (14)
Document Type
- Article (14)
Language
- English (14)
Is part of the Bibliography
- yes (14)
Keywords
Institute
Functional biodiversity research explores drivers and functional consequences of biodiversity changes Land use change is a major driver of changes of biodiversity and of biogeochemical and biological ecosystem processes and services However, land use effects on genetic and species diversity are well documented only for a few taxa and trophic networks We hardly know how different components of biodiversity and their responses to land use change are interrelated and very little about the simultaneous, and interacting, effects of land use on multiple ecosystem processes and services Moreover, we do not know to what extent land use effects on ecosystem processes and services are mediated by biodiversity change Thus, overall goals are on the one hand to understand the effects of land use on biodiversity and on the other to understand the modifying role of biodiversity change for land-use effects on ecosystem processes, including biogeochemical cycles To comprehensively address these Important questions, we recently established a new large-scale and long-term project for functional biodiversity, the Biodiversity Exploratories (www biodiversity-exploratories de) They comprise a hierarchical set of standardized field plots in three different regions of Germany covering manifold management types and intensities in grasslands and forests They serve as a joint research platform for currently 40 projects involving over 300 people studying various aspects of the relationships between land use biodiversity and ecosystem processes through monitoring, comparative observation and experiments We introduce guiding questions, concept and design of the Biodiversity Exploratories - including main aspects of selection and implementation of field plots and project structure - and we discuss the significance of this approach for further functional biodiversity research This includes the crucial relevance of a common study design encompassing variation in both drivers and outcomes of biodiversity change and ecosystem processes, the interdisciplinary integration of biodiversity and ecosystem researchers, the training of a new generation of integrative biodiversity researchers, and the stimulation of functional biodiversity research in real landscape contexts, in Germany and elsewhere.
Understanding the natural history of model organisms is important for the effective use of their genomic resourses. Arabidopsis lyrata has emerged as a useful plant for studying ecological and evolutionary genetics, based on its extensive natural variation, sequenced genome and close relationship to A. thaliana. We studied genetic diversity across the entire range of European Arabidopsis lyrata ssp. petraea, in order to explore how population history has influenced population structure. We sampled multiple populations from each region, using nuclear and chloroplast genome markers, and combined population genetic and phylogeographic approaches. Within-population diversity is substantial for nuclear allozyme markers (mean P = 0.610, A(e) = 1.580, H-e = 0.277) and significantly partitioned among populations (F- ST = 0.271). The Northern populations have modestly increased inbreeding (F-IS = 0.163 verses F-IS = 0.093), but retain comparable diversity to central European populations. Bottlenecks are common among central and northern Europe populations, indicating recent demographic history as a dominant factor in structuring the European diversity. Although the genetic structure was detected at all geographic scales, two clear differentiated units covering northern and central European areas (F-CT = 0.155) were identified by Bayesian analysis and supported by regional pairwise F-CT calculations. A highly similar geographic pattern was observed from the distribution of chloroplast haplotypes, with the dominant northern haplotypes absent from central Europe. We conclude A. l. petraea's cold-tolerance and preference for disturbed habitats enabled glacial survival between the alpine and Nordic glaciers in central Europe and an additional cryptic refugium. While German populations are probable peri-glacial leftovers, Eastern Austrian populations have diversity patterns possibly compatible with longer-term survival.
The tettigoniid genus Phlesirtes Bolivar and its allies are reviewed. Morphological, ecological and molecular data prompt the erection of the new genus Chortoscirtes gen.n. with type species Xiphidion meruense Sjostedt. The genera Phlesirtes, Chortoscirtes, Karniella and Naskreckiella are characterized by morphological characters supported by molecular, acoustic, ecological and chromosomal data. Four species, Chortoscirtes pseudomeruensis sp.n., C. masaicus sp.n., C. puguensis sp.n. and C. serengeti sp.n., are described from localities in northern and coastal Tanzania and one Karniella, K. crassicerca sp.n., is described from Uganda. The following comb n. are proposed: Phlesirtes kibonotensis (Sjostedt) and Phlesirtes kilimandjaricus (Sjostedt). Subtribal status is proposed for the four investigated African genera. A key to the Chortoscirtes species is provided.
A new genus is proposed for a new East African Phaneropterinae species, Lunidia viridis, occurring on Mt. Kilimanjaro, Tanzania. Based on 33 records, notes on distribution and habitat are given, as well as acoustical data provided. Climate and vegetation parameters obtained along several transects on Mt. Kilimanjaro were evaluated describing the ecological niche of the new species. This interdisciplinary approach allows not only a profound characterisation of the ecological demands of the new genus but also predictions of the potential distribution area, which is tested for the first time for an African bush cricket species. Lunidia viridis n. gen. n. sp. occurs within humid and perhumid forests and Chagga home gardens, avoiding subhumid conditions on the mountain. It is found from 1,330 m upwards on the southern slopes, whereas the same ecological conditions are expressed from 1,930 m upwards on the drier northern slopes. Lunidia viridis has an unusually complex and variable song, which is described from field and laboratory recordings. The FISH technique for characterizing chromosomes is applied for the first time for an African species; L. viridis exhibits a karyotype typical for most Tettigoniidae.
Melanoscirtes gen.n. is established within Karniellina. The members of this subtribe are small conocephaline bush crickets, confined to Africa. Melanoscirtes is erected on Phlesirtes kibonotensis, a species restricted to forest clearings and forest edge in the submontane and montane zones of Mt. Kilimanjaro. A subspecies, M. kibonotensis uguenoensis, is described from the North Pare mountains, a mountain range of the Eastern Arc adjacent to Mt. Kilimanjaro. Further species of Melanoscirtes occur on other mountain ranges of the northern branch of the Eastern Arc mountains of northern Tanzania and southern Kenya. The South Pare mountains harbour M. shengenae; the West Usambaras, M. usambarensis, and the Taita Hills, M. taitensis. All species and subspecies of Melanoscirtes exhibit a similar morphology and occupy analogous habitats on the respective mountains. The song patterns for all species found within this genus are very similar, and this, together with evidence from molecular data, suggests that allopatric speciation is the reason for the biogeographic pattern found in this genus. A key for the subspecies and species of Melanoscirtes is provided.
A new genus, Altihoratosphaga, is erected for species formerly assigned to Horatosphaga Schaum, 1853, and a new species is described. Four species are included in Altihoratosphaga: Altihoratosphaga nomima (Karsch, 1896), Altihoratosphaga montivaga (Sjostedt, 1909), Altihoratosphaga nou (Hemp, 2007) and Altihoratosphaga hanangensis sp. nov. All four species are restricted to Tanzanian localities, and, except for A. nomima, for which no ecological data are available, are confined to montane forest habitats. Data on ecology, acoustics, chromosomes, and molecular relationships are provided, as well as a key to Altihoratosphaga species. The present-day distribution of Altihoratosphaga species suggests former migration events at times when wetter and colder climatic fluctuations favoured connections between montane forest communities, which today are isolated, enabling flightless taxa such as Altihoratosphaga and Monticolaria to spread.
Land use is increasingly recognized as a major driver of biodiversity and ecosystem functioning in many current research projects. In grasslands, land use is often classified by categorical descriptors such as pastures versus meadows or fertilized versus unfertilized sites. However, to account for the quantitative variation of multiple land-use types in heterogeneous landscapes, a quantitative, continuous index of land-use intensity (LUI) is desirable. Here we define such a compound, additive LUI index for managed grasslands including meadows and pastures. The LUI index summarizes the standardized intensity of three components of land use, namely fertilization, mowing, and livestock grazing at each site. We examined the performance of the LUI index to predict selected response variables on up to 150 grassland sites in the Biodiversity Exploratories in three regions in Germany(Alb, Hainich, Schorlheide). We tested the average Ellenberg nitrogen indicator values of the plant community, nitrogen and phosphorus concentration in the aboveground plant biomass, plant-available phosphorus concentration in the top soil, and soil C/N ratio, and the first principle component of these five response variables.
The LUI index significantly predicted the principal component of all five response variables, as well as some of the individual responses. Moreover, vascular plant diversity decreased significantly with LUI in two regions (Alb and Hainich).
Inter-annual changes in management practice were pronounced from 2006 to 2008, particularly due to variation in grazing intensity. This rendered the selection of the appropriate reference year(s) an important decision for analyses of land-use effects, whereas details in the standardization of the index were of minor importance. We also tested several alternative calculations of a LUI index, but all are strongly linearly correlated to the proposed index.
The proposed LUI index reduces the complexity of agricultural practices to a single dimension and may serve as a baseline to test how different groups of organisms and processes respond to land use. In combination with more detailed analyses, this index may help to unravel whether and how land-use intensities, associated disturbance levels or other local or regional influences drive ecological processes.
Silvicultural practices lead to changes in forest composition and structure and may impact species diversity from the overall regional species pool to stand-level species occurrence. We explored to what extent fine-scale occupancy patterns in differently managed forest stands are driven by environment and ecological traits in three regions in Germany using a multi-species hierarchical model. We tested for the possible impact of environmental variables and ecological traits on occupancy dynamics in a joint modelling exercise while taking possible variation in coefficient estimates over years and plots into account. Bird species richness differed across regions and years, and trends in species richness across years were different in the three regions. On the species level, forest management affected occupancy of species in all regions, but only 35% of the total assemblage-level variation in occurrence probability was explained by either forest type and successional stage and <?1% by forest edge. On the assemblage level, bird occurrence decreased with body mass in all regions. Species with smaller breeding ranges had lower occurrence probabilities in one region, while later spring arrival decreased occurrence probabilities in the two other regions. Spatial variation in the effect size of trait covariates such as species phylogeny and breeding strata showed that variation in patch occupancy due to fine-scale differences in forest management is, to some extent, predictable from ecological traits. Our results show that environmental factors and ecological traits jointly predict variation in bird occupancy patterns and their response to forest management. Observations at the fine scale of forest stands, at which conservation efforts can be arranged along with forest management practices in heterogeneous environments, have been shown to provide meaningful insights despite the difficulties involved in monitoring mobile organisms such as birds at the plot level.
In soil, Acidobacteria constitute on average 20% of all bacteria, are highly diverse, and are physiologically active in situ. However, their individual functions and interactions with higher taxa in soil are still unknown. Here, potential effects of land use, soil properties, plant diversity, and soil nanofauna on acidobacterial community composition were studied by cultivation-independent methods in grassland and forest soils from three different regions in Germany. The analysis of 16S rRNA gene clone libraries representing all studied soils revealed that grassland soils were dominated by subgroup Gp6 and forest soils by subgroup Gp1 Acidobacteria. The analysis of a large number of sites (n = 57) by 16S rRNA gene fingerprinting methods (terminal restriction fragment length polymorphism [T-RFLP] and denaturing gradient gel electrophoresis [DGGE]) showed that Acidobacteria diversities differed between grassland and forest soils but also among the three different regions. Edaphic properties, such as pH, organic carbon, total nitrogen, C/N ratio, phosphorus, nitrate, ammonium, soil moisture, soil temperature, and soil respiration, had an impact on community composition as assessed by fingerprinting. However, interrelations with environmental parameters among subgroup terminal restriction fragments (T-RFs) differed significantly, e.g., different Gp1 T-RFs correlated positively or negatively with nitrogen content. Novel significant correlations of Acidobacteria subpopulations (i.e., individual populations within subgroups) with soil nanofauna and vascular plant diversity were revealed only by analysis of clone sequences. Thus, for detecting novel interrelations of environmental parameters with Acidobacteria, individual populations within subgroups have to be considered.
The relationship of different types of grassland use with plant species richness and composition ( functional groups of herbs, legumes, and grasses) has so far been studied at small regional scales or comprising only few components of land use. We comprehensively studied the relationship between abandonment, fertilization, mowing intensity, and grazing by different livestock types on plant diversity and composition of 1514 grassland sites in three regions in North-East, Central and South-West Germany. We further considered environmental site conditions including soil type and topographical situation. Fertilized grasslands showed clearly reduced plant species diversity (-15% plant species richness, -0.1 Shannon diversity on fertilized grasslands plots of 16m(2)) and changed composition (-3% proportion of herb species), grazing had the second largest effects and mowing the smallest ones. Among the grazed sites, the ones grazed by sheep had higher than average species richness (+27%), and the cattle grazed ones lower (-42%). Further, these general results were strongly modulated by interactions between the different components of land use and by regional context: land-use effects differed largely in size and sometimes even in direction between regions. This highlights the importance of comparing different regions and to involve a large number of plots