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Biodiversity in agroecosystems: a multi-trophic approach to metacommunities

Das Projekt "Biodiversity in agroecosystems: a multi-trophic approach to metacommunities" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Institut für Biologie II durchgeführt. The goal of the proposal is to explore the structure and functioning of metacommunities in ecological compensation areas at a multi-trophic level. First, we will assess the effect of plant diversity and herbivore and/or predator exclusion on metacommunity functioning in sown wildflower strips. We will document the communities inhabiting these experimental plots, paying attention at interactions between species, and with consideration of larger consumers linking these habitats with the surrounding matrix. Second, we will explore the relationship between various measures of the environment (isolation, habitat size) and descriptors of the metacommunities (diversity, composition, abundances, and productivity of various taxonomic groups, food-web structure, temporal variability, local invasions and extinctions). Third, using a high-quality dataset on quantitative food webs and the present data, we will conduct meta-analyses to test various models of community organisation (neutral models of biodiversity, species-area relationship in trophic levels, regional similarity hypothesis, food-web structure). Fourth, we will develop various models describing food-web structure and metacommunities dynamics. We will synthesize our results to develop a theory of 'meta food-webs'. Fifth, we will apply the gained knowledge to improve current agri-environment schemes. The study of species interactions in spatially structured metacommunities is comprehensive and global. As such, this project has a strong potential to provide fundamental insight into conservation biology. This project is multidisciplinary, putting together practitioners, ecologists and mathematicians, and is expected to yield important results both of fundamental and conservation relevance. We will use various methodologies to reach our goals. For the first part, we will set up an experiment with replicated sown wildflower strips where plant species richness and the abundance of major predators (foxes and birds of prey) and/or of major herbivores (voles and slugs) will be controlled (balanced incomplete block design). The other parts will rely on classical meta-analyses, multivariate statistics, and mathematical modelling. For the latter part, we will develop stochastic models to explore the dynamics of communities.

Grassland management: designing tomorrow's farmland for biodiversity

Das Projekt "Grassland management: designing tomorrow's farmland for biodiversity" wird vom Umweltbundesamt gefördert und von Universität Bern, Abteilung Synökologie Institut für Ökologie und Evolution durchgeführt. The loss of farmland heterogeneity has triggered a farmland biodiversity crisis. Agri-environmental schemes are voluntary programmes designed to restore farmland biodiversity by financially supporting farmers who modify their farming practice to provide environmental benefits. Although some 25Prozent of European farmland is under some sort of agri-environmental contract, these programmes provide only mixed benefits for biodiversity. The restoration of farmland wildlife is believed to require changes that go further than the traditional extensification suggested by most programmes. In 2008-2011, the Swiss federal government provides more than CHF 11 billions to direct payments, part of which supporting incentives for biodiversity. It is thus essential to ensure that these measures provide the best return on investment for biodiversity. In the Swiss lowlands, low intensity managed grasslands are by far the most common and most extended type of Ecological Compensation Area. It is therefore where the greatest biodiversity restoration potential exists in the lowlands. Here we experimentally modify mowing regime in low-intensity managed grasslands so as to increase spatial, structural and ecological heterogeneity. Mountain agro-ecosystems are undergoing rapid land use changes in the Alps, partly due to intensification of meadowland management, which causes a dramatic decrease of biodiversity. Here we study experimentally the effect of aerial irrigation and liquid manure spraying, two novel, seemingly detrimental management regimes for wildlife, on mountain grassland biodiversity. Changes in biodiversity, taxon-specific biomasses and food chain functionalities will be estimated using responses from different plant and animal taxa representative for grassland communities. In addition, changes in hay yield and quality will be assessed. The expected outcome will help understanding the dynamics of grassland communities and ecosystem functions in both lowland and mountain farmland in response to implementable changes in management practice. By confronting agronomic data with biodiversity and biomass metrics we shall provide guidance for better agri-environmental policies, which will help in optimizing the biodiversity benefits expected from the flow of subsidies towards agri-environmental schemes.

Genetic diversity, ecotype differentiation and population biology of an endangered primeval-forest lichen, Lobardia pulmonaria in a suture zone in the Ural Mountains

Das Projekt "Genetic diversity, ecotype differentiation and population biology of an endangered primeval-forest lichen, Lobardia pulmonaria in a suture zone in the Ural Mountains" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. Lichen conservation biology is often faced with widely distributed, but strongly fragmented taxa. If in a global Red List assessment such a taxon is treated as one single unit, one large and stable population may result in a low conservation status of the global population, despite the fact that most populations face a strong decline. In case the global population of a taxon is subdivided into evolutionary significant units (ESU), an individual Red List status might be assigned to each ESU. However, the complex life cycles and long generation times make it very difficult to identify ESU for lichens if ecological differentiation is the crucial criterion for their distinction. As an alternative approach to delimit ESU, genetic differentiation of regional populations has been suggested. Recent developments of molecular markers demonstrated considerable levels of regional genetic differentiation among populations within species and during our first Scopes project we found high levels of genetic differentiation within L. pulmonaria between biogeographic regions in Russia. We identified a broad suture zone of two different evolutionary lineages in the Ural Mountains. The western lineage, as identified by ITS sequences is widely distributed in Africa and Western, Northern and Central Europe. The eastern lineage was found so far in Russia East of the Urals and in North America. Concerning the differentiation within the two ITS types it is likely that these genetically differentiated populations of L. pulmonaria developed independently over considerable evolutionary periods rather than became demographically autonomous through recent isolation, e.g. during anthropogenic deforestation. In this project we will sample additional populations along this suture zone, as well as east and west of it to study possible gene flow between the two distinct evolutionary lineages. In order to test if the genetic differentiation found in regional populations parallel ecological adaptation, we had established a provenance clone test during our first Scopes project. We expect that during the coming three years the growth of the transplants will have reached an optimal level, which will then allow to test if survival and growth rate, diaspore production and degree of parasite attack differ between the provenances from the Carpathians, the Ural Mountains, The Komi Republic and Sakhalin. A differentiation between the studied L. pulmonaria population into regional ecotypes would have a significant impact on the conservation status of this species, because its global population could be subdivided into regional ESU.

Klimaaenderungen im subalpinen-alpinen Oekoklin: Genetische Variabilitaet und adaptives Potenzial ausgewaehlter Arten

Das Projekt "Klimaaenderungen im subalpinen-alpinen Oekoklin: Genetische Variabilitaet und adaptives Potenzial ausgewaehlter Arten" wird vom Umweltbundesamt gefördert und von Universite de Neuchatel, Institut de Botanique durchgeführt. The present project consists partly in a direct continuation of phase I of the genetic part of Ecocline, in particular by the experimental test of hypotheses formulated in its context. Moreover, it innovates by the study of two species potentially very sensitive to climate change and differing by their breeding systems. It focuses on two perspectives: a) Investigation of genetic clines along temperature gradients in order to develop tools to assess the genetic reaction of species to climate change. Clines in allele frequency along altitudinal gradients were discovered for the grass Anthoxanthum alpinum during phase I. Reciprocal transplant experiments are being performed in order to test ecotypic differentiation between low and high altitude populations of A. alpinum, together with the differential action of selection on genetic markers correlated with altitude. b) Pattern of genetic variability within and between populations as a measure of the adaptive potential of the species. Species are often considered as genetically static. Consequently, it is generally assumed that migration is the only possible alternative to extinction when new environmental conditions occur. Nevertheless, genetic variability is an important parameter for the future of a species enduring climate change. Adaptation through changes in the genetic structure of a population under new pressures of selection may allow a species to endure climate change without modifications of its range. In that respect, the variation in the number and in the size of clones by the polymorphism of AFCP in the dwarf shrub Vaccinium myrtillus (bilberry) is determined. That part will fulfill, with the use of fingerprinting techniques, the program started during the first phase of the project . That study will assess if there is a decrease in the number of clones as a function of altitude and if some clones are associated with specific environmental conditions (ecotypic differentiation). Moreover, isozyme polymorphism was investigated on one species particularly threatened by climate change, Campanula excisa, a rare monoecious endemic of central Alps present only in upper Valais in Switzerland. No correlation was found between the size of the patches, the altitude and the genetic diversity, even if genetic differences between the patches were observed. Leading Questions: Does genetic diversity change along attitudinal gradients? Are genetic markers correlated with altitude? If yes. are they submitted to selection? What will be the effect of global change on the genetic diversity of species? Is it possible to use genetic markers for monitoring the reaction of species to climate change?

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