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Assessment of genetic diversity of legumes in the highlands of Northern Vietnam for genetic resource conservation and sustainable landuse

Increasing population pressure is leading to unsustainable land use in North Vietnamese highlands and destruction of natural habitats. The resulting loss of biodiversity includes plant genetic resources - both wild (= non-cultivated) species and cultivated landraces - adapted to local conditions, and local knowledge concerning the plants. A particularly important group among endangered plants are the legumes (1) because Southeast Asia is a major centre of genetic diversity for this family, and (2) because the potential contribution of legumes to sustainable land use is, due to their multifunctionality (e.g., soil improvement, human and livestock nutrition), especially high. The project aims to contribute to the conservation and sustainable use of genetic resources of legumes with an integrated approach wherein a series of components are combined: (1) A participatory, indigenous knowledge survey complemented by information from the literature; (2) germplasm collection missions (for ex situ conservation) complemented by field evaluation and seed increase; (3) genetic diversity analysis of selected material by molecular markers; and (4) GIS based analysis of generated data to identify areas of particular genetic diversity as a basis for land area planning and in situ preservation recommendations. Project results are expected to be also applicable to similar highlands in Southeast Asia.

Forschergruppe (FOR) 1501: Resilience, Collapse and Reorganisation in Social-Ecological Systems of East- and South Africa's Savannahs, Vulnerability and Resilience of Rangeland Vegetation as Affected by Livestock Management, Soils and Climate

The vegetation of East and South African savannahs has been shaped by the complex interaction of geo-biophysical processes and human impact. For both regions a controversial discussion is pertinent, as to whether massive degradation threatens the sustainability of livelihoods in these regions. Rangeland vegetation is mainly affected by environmental conditions (soil and climate) and by livestock management. Extent and interaction of these drivers are not well understood but have profound impacts on the resilience and vulnerability of these systems to be shifted toward unfavourable degraded or bush encroached states. The project aims to analyse and model rangeland vegetation in response to range management including livestock, soil quality and climatic conditions and to assess the impacts of changes in these conditions on the resilience and vulnerability of rangeland systems. Field measurements, remote sensing of vegetation patterns and dynamics and simulation modelling will be used to understand the dynamics of rangeland vegetation. We will use the 'fast' or 'state' variables potential of pastures to produce palatable biomass, the variability of this production, and the system's potential to recover from disturbance impact as indicators of resilience. 'slow' variables that control (or drive) the 'fast' variables such as management, climate and soil variables are recorded in cooperation with other subprojects as with A1 for soil variables. Results of the project will show which management activities are most favourable for individual regions to sustain plant production in the long term.

Populationsmodell des Auerhuhns in den Schweizer Alpen: Grundlagen für den Artenschutz

Das Auerhuhn ist eine stark gefährdete Brutvogelart der Schweiz. Veränderungen in der Zusammensetzung und Nutzung des Waldes haben dazu geführt, dass sich die Bestände dieses Raufusshuhns in den letzten drei Jahrzehnten halbiert haben. Deshalb sollen die Lebensraumansprüche des attraktiven Waldvogels vermehrt in der Planung und Umsetzung von Waldreservaten und der Bewirtschaftung von Wäldern der höheren Lagen berücksichtigt werden. Auf der kleinen räumlichen Ebene sind die Habitatsansprüche der Art durch Untersuchungen in West- und Mitteleuropa (Storch 1993, 2002, Schroth 1994) und Skandinavien relativ gut bekannt. Dagegen werden die Populationsprozesse auf der Ebene der Landschaft erst in Ansätzen verstanden (Sjöberg 1996, Kurki 2000). Entsprechend konnte man die Bestandsrückgänge in den meisten Gebieten Europas noch nicht stoppen, da einerseits genauere Kenntnisse über das Zusammenspiel und die relative Bedeutung der einzelnen Faktoren fehlen (Habitatqualität, Störungen, Prädatoren, Witterung-Klima, Huftierkonkurrenz), und andererseits noch nicht versucht wurde, die Bestandsentwicklung im grossen landschaftlichen Massstab als Metapopulationsdynamik zu verstehen. Es ist das primäre Ziel dieses Projekts, ein räumlich explizites Metapopulationsmodell des Auerhuhns für einen grossen Landschaftsausschnitt der Schweizer Alpen zu erarbeiten. Dabei sollen die erwähnten Einflussfaktoren möglichst umfassend berücksichtigt werden. Die Arbeit soll modellhaft zeigen, dass für das Verständnis von Populationsvorgängen von raumbeanspruchenden Wildtierarten eine Analyse und Bewertung von lokal bis überregional wirksamen Einflussfaktoren notwendig sind. Die Ergebnisse sollen zudem als konzeptionelle Grundlage für den Nationalen Aktionsplan Auerhuhn und für regionale Artenförderungsprojekte dienen. Folgende Fragen und Themen sind für das Projekt von zentraler Bedeutung: Wie gross ist das landschaftsökologische Lebensraumpotenzial für das Auerhuhn in den Alpen, wie ist es räumlich verteilt? Wie verteilen sich die lokalen Auerhuhnpopulationen in diesen Potenzialgebieten? Wie gross sind die Bestände? Welche Faktoren beeinflussen den Status von Lokal- und Regionalpopulationen? Welche Populationen haben abgenommen oder sind verschwunden, welche sind stabil (Source-Sink-Mechanismen)? Zwischen welchen räumlich getrennten Populationen besteht ein Austausch? Welche Landschaftselemente wirken als Barrieren? Entwickeln einer nicht-invasiven Methode für die genetische Differenzierung von Populationen, sowie für Bestandsschätzungen und Monitoring.

Ecological valuation of crop pollination in traditional Indonesian homegardens

Traditional Indonesian homegardens harbour often high crop diversity, which appears to be an important basis for a sustainable food-first strategy. Crop pollination by insects is a key ecosystem service but threatened by agricultural intensification and land conversion. Gaps in knowledge of actual benefits from pollination services limit effective management planning. Using an integrative and agronomic framework for the assessment of functional pollination services, we will conduct ecological experiments and surveys in Central Sulawesi, Indonesia. We propose to study pollination services and net revenues of the locally important crop species cucumber, carrot, and eggplant in traditional homegardens in a forest distance gradient, which is hypothesized to affect bee community structure and diversity. We will assess pollination services and interactions with environmental variables limiting fruit maturation, based on pollination experiments in a split-plot design of the following factors: drought, nutrient deficiency, weed pressure, and herbivory. The overall goal of this project is the development of 'biodiversity-friendly' land-use management, balancing human and ecological needs for local smallholders.

Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)

Toona ciliata (Australian red cedar) is highly valued for veneer and furniture production and endangered in its natural ecosystems due to exploitation. This work aims to improve the availability of this wood on the market and help reduce pressure on the species in its native environment. An afforestation project cultivating Toona ciliata was introduced to the study site in Misiones, Argentina. The local cultivation faces losses caused by drought and frost, because T. ciliata requires overstory protection when young. Consequently, Grevillea robusta, Pinus elliottii x Pinus caribaea, and Pinus taeda, nurse tree species which also produce sought-after wood were chosen to provide protection. One-year-old T. ciliata seedlings were planted underneath each of the six-year-old nurse species. An inventory after one year indicated that both survival and height increment were highest underneath G. robusta and lowest underneath P. elliottii x P. caribaea. In this study I am examining possible facilitation and competition mechanisms between the overstory and understory T. ciliata. Extensive empirical data collected over the course of 3 years will be utilized to project potential growth scenarios for several rotations using a computer based forest growth model.

Conflict Resolution, Management and Problem Solving for Sustainable Resource Utilization (COMPROMISE)

Renewable natural resources (e.g. fish stocks and forests) are threatened worldwide due to non-sustainable exploitation and global environmental change, making depending industries and regions vulnerable. Over-exploitation is typically characterized by over-capitalization and destructive competition between small-scale and regionally/globally acting enterprises. In COMPROMISE the complex interactions between natural, social and institutional systems related to this will be investigated with an integrative approach. It is a key feature of such system that they characterised by low levels of knowledge. This holds for the dynamics of stocks, the economic characteristics of firms, strategies of the fishing industry, as well as for the impact of policy frameworks. Thus, in order to provide further knowledge qualitative methods are needed. The encompassing analysis starts with case studies of some fisheries in developing countries under stakeholder involvement. Typical factors and agents, patterns and conflicts will be characterized by drawing from expertise from system analysts, social and natural scientists, combined with modern modelling methods. The aim is to identify success factors for a sustainable management of renewable resources.

Non-indigenous insects and their threat to biodiversity and economy in the Balkans

Invasive alien species are recognized as one of the leading threats to biodiversity. They also impose enormous costs on agriculture, forestry and human health. In Europe and elsewhere, most countries are presently developing national and international strategies to assess the full scope of the danger represented by invasive non-indigenous species, and to take the necessary measures to prevent and manage the threat effectively. The initial step in a national programme against non-indigenous species must be a survey of the species already established in the country, as well as those species which are likely to invade the country in the near future, together with their perceived, actual and potential economic and environmental impact. In this project, we propose to carry out an inventory of non-indigenous insects in Bulgaria, Macedonia and Albania. The general objective of the project is to provide these three countries wit information on invasive alien insects in the Balkans and to develop local expertise in the field of invasive alien species management. This will allow the development of national strategies against alien insects, and non-indigenous organisms in general. Firstly, a database on non-indigenous insects established in Bulgaria, Macedonia and Albania will be set up. Then, we will provide informative fact sheets for the 30-40 main invasive, or potentially invasive, insects in the region. Finally, we will analyse the data to extract information on pathways, species or ecosystems traits that make them prone to invasion, and we will incorporate these analyses into similar studies carried out as part of on-going European projects on risk and impact assessment. In addition, as a case study, we are assessing the impact of the horse-chestnut leaf miner, Cameraria ohridella, an invasive moth which first appeared in the Balkans in the 1980s before spreading to the whole of Europe, and which is suspected to threaten the few remaining endemic stands of horse-chestnut (Aesculus hippocastanum) in the Balkans.

Forest management and habitat structure - influences on the network of song birds, vectors and blood parasites

Forest structure is altered by humans for long times (Bramanti et al. 2009). The long lasting modification of forests pursuant to human demands modified the living conditions for birds as well as for many other animals. This included changes in resource availability (e.g., food, foraging, nesting sites) and changes of interspecific interactions, e.g., parasitism and predation (Knoke et al. 2009; Ellis et al. 2012). Also species compositions and the survivability of populations and even species are affected. The loss of foraging sites and suitable places for reproduction, the limitation of mobility due to fragmented habitats and the disturbances by humans itself may lead to more stressed individuals and less optimal living conditions. In certain cases species are not able to deal with the modified requirements and their populations will shrink and even vanish. Depending on the intensity of management and the remaining forest structure, biodiversity is more or less endangered. Especially in systems of two or more strongly connected taxa changing conditions that affect at least one part may subsequently affect the other, too. One system of interspecific communities that recently attracted the attention of biologists includes birds, blood parasites (haemosporidians) and their transmitting vectors. For instance, avian malaria (Plasmodium relictum) represents the reason for extreme declines in the avifauna of Hawaii since the introduction of respective vectors (e.g. Culicidae) during the 20th century (van Riper et al. 1986, Woodworth et al. 2005). With the current knowledge of this topic we are not able to predict if such incidences could also occur in Germany. All in all, different management strategies and intensity of forest management may influence the network of birds, vectors and blood parasites and change biodiversity. To elucidate this ecological complex, and to understand the interactions of the triad of songbirds as vertebrate hosts, dipteran vectors and haemosporidians within changing local conditions, I intend to collect data on the three taxa in differently managed forest areas, the given forest structure and the climatic conditions. I will try to explain the role of abiotic factors on infection dynamics, in detail the role of forest management intensity. Data acquisition takes place at three spatially divided locations: inside the Biodiversity Exploratory Schwäbische Alb, at the Mooswald in Freiburg, and inside the Schwarzwald.

The South Moresby Controversy (1974-1993) - stories about the resource conflict over logging on Haida Gwaii, Canada

In my Phd-study, I examine the resource conflict over industrial logging in the South Moresby area on Haida Gwaii (former Queen Charlotte Islands) from 1974 to 1993. On this remote archipelago on British Columbias west-coast, a fierce dispute over logging practices, land rights, Aboriginal land claims and environmental issues had emerged in the face of devastating logging practices were not only threatening to destroy large parts of Moresby Island but also resulted in the destruction of salmon streams. The two major natural resources available on the islands were at stake during the 'war in the woods.' Together with environmentalist, the Haida First Nation successfully fought for the preservation of Gwaii Haanas (South Moresby Island) with blockades, protests, environmental campaigns, lobbying and legal action. The area is now protected as the 'Gwaii Haanas National Park Reserve.-' Using a cultural approach combining aspects of 'storytelling,' the 'cultural memory' and 'actor-network-theory' (ANT), the core question arises whether the (Western) dualisms between 'nature' and 'culture' and between 'fact' and 'fiction' should be dissolved. Latour argues that such dualisms and even the separation between the human and non-human world (i.e., the world of things) do not exist. Assmann claims that we do not necessarily remember what has really happened', but what was repeatedly told us to have happened. Along with Thomas King, J. Edward Chamberlin and William Cronon, I stress the point that stories - fictitious or based on facts - do matter. The effect of stories on the way we understand our past, might often be more important than that of 'hard' facts: Stories shape both a societys concept of the past and its present identity. Canada, with its heterogeneous population, is a particularly interesting place to conduct research about different concepts of 'nature' and culture'. Analyzing the different stories that evolved around South Moresby, and taking into account diverging messages of native and non-native stories, offers a new perspective on similar resource conflicts that continue to exist and arise all over the world.

Effects of climate change on past, recent, and future biodiversity of alpine/arctic plants: Integrative evidence from phylogenies, population genetics, ecological niche modelling and new insights for conservation

Responding to the twin crises of global warming and biodiversity loss requires a deep understanding of how climate affects the processes that generate and destroy biodiversity, primarily through its effects on the ecology and distribution of species. Recent improvements in our ability to reconstruct the history of biodiversity through timed phylogenies, estimate changes in genetic diversity, and predict the potential distribution of selected species with ecological niche models (ENMs) now allow us to infer the evolution of ecological preferences and distributional ranges at different temporal scales. Our two case studies focus on alpine/arctic regions, because they are among those most endangered by global warming. The first study will use, for the first time, a combination of ENM and phylogeny to test the model of hybrid, polyploid speciation by secondary contact in arctic/alpine plants. We selected Primula sect. Aleuritia (simply Aleuritia, from here on), because our previous phylogenetic work provided clear hypotheses for the parental origins of polyploids, yet the distributions of the inferred progenitors do not currently overlap. Did the ranges of the proposed parents overlap at the time of allopolyploid origins, as predicted by the secondary contact model? To answer this question, we will produce a high-resolution, dated phylogeny of Aleuritia, optimize the ecological preferences of the hypothesized progenitors onto the dated phylogeny, and project their past distributional ranges onto the fine-resolution climatic scenarios recently developed for the Pleistocene. In the second case study, we will try to explain how small populations persisted on summits in the past and how they are affected by current and future climate change. Here we selected Saxifraga florulenta, a rare, endemic species of the Maritime Alps, because hypotheses of its phylogenetic relationships are available from our previous work, it occurs exclusively above 2000 m, and has very narrow ecological requirements. Consequently, if current trends of global warming continue, the strict ecological adaptation of S. florulenta to siliceous substrates at the highest altitudes of the Maritime Alps may represent a serious extinction risk. We will investigate whether the phylogeographic history, genetic diversity, climatic niche and dispersal mode of S. florulenta can explain its long persistence in the Maritime Alps, a hot spot of biodiversity, and predict its future survival or extinction on mountain tops. We will use a combination of genetic analysis and niche modeling to reconstruct changes in the niche, geographic distribution, and genetic diversity of this cold-adapted species.

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