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To understand the rapid rate of change in global biodiversity, it is necessary to analyse the present condition of ecosystems and to elucidate relationships of species to their environment. The BIOKLIM Project (Biodiversity and Climate Change Project) is intended to close this gap in our knowledge of montane and high montane forests of Central European low mountain ranges, one of the most threatened mixed montane systems worldwide. The Bavarian Forest National Park is characterised by its altitude range of ca. 800 m and a strongly developed gradient of forest structure. Relicts of old growth forests (areas of former local nature reserves) and dead stands, mostly killed by bark beetles, are accompanied by widely varying levels of woody debris and light. The gradients comprise a wide range of abiotic and forest structure factors, making the study area well suited for a multidisciplinary investigation of biodiversity. Unconstrained ordination (CA) of six taxa (vascular plants, wood inhabiting fungi, birds, carabids, spiders and molluscs) indicate the altitudinal gradient to be the main driver for distribution patterns of species assemblages. Objectives, structure, study design and data sampling of the BIOKLIM Project are described in detail. We set up 293 sampling plots along four main straight transects following the altitudinal gradient. All abiotic and stand structure data regarded as relevant are available for each plot. Vascular plants, wood inhabiting fungi and birds were sampled or mapped on all 293 plots. For the other 22 investigated taxa we used subsamples pre-stratified according to the sampling methods. The necessity of dealing with spatial autocorrelation, arising from sampling along linear transects, is described. Finally, study approach of our biodiversity project is compared with others involving altitudinal gradients. Worldwide, only a few multidisciplinary biodiversity studies have been previously conducted on long altitudinal gradients. However, in most cases sampling techniques were similar to ours, which allows comparison of results between continents. Keywords: Climate Change, Biodiversity, species-environment relationships
In over 100 genera of tropical angiosperms, one or more species possess specialised structures for housing ants. The longevity and intimacy of these associations has often facilitated an increasing specialisation of both the ants and the plants, leading to a number of highly specific and obligate symbioses. Early literature contained only few anecdotal reports of the ant genus Cladomyrma WHEELER inhabiting (unidentified) plants. This work presents the new findings on Cladomyrma and its host plants that accumulated over the last two decades. My studies of Cladomyrma reveal that there is a largely overlooked community of south-east Asian plant-ants and their associated plants. Currently the genus consists of at least 12 species. Cladomyrma has been thought to be restricted to the ever-wet part of the West Malesian floristic region, comprising the Malay Peninsula, Borneo, and Sumatra, but recent collections from Thailand and Vietnam indicate that species of the genus penetrate the seasonal tropical forests of Continental Asia. Cladomyrma inhabits 24 plant species belonging to a surprisingly extensive range of plant taxa: Callerya, Saraca, Spatholobus (Fabaceae), Crypteronia (Crypteroniaceae), Drypetes (Putranjivaceae), Ryparosa (Achariaceae), Strychnos (Loganiaceae), Neonauclea (Rubiaceae), Luvunga (Rutaceae) and Sphenodesme (Verbenaceae). In terms of taxonomic diversity on the genus and family level the range of hosts utilised by Cladomyrma is one of the broadest ever recorded for any live stem-nesting plant-ant lineage worldwide. This work provides a species-level overview of all Cladomyrma host plants known from Borneo, the Malay Peninsula and Sumatra, including descriptions of ant-housing structures (domatia), ant inhabitant identity, onset of colonisation during plant ontogeny, nest structure, occupancy rate, and considerations of results obtained from herbarium specimens. Both the regularity of ant association and the degree of morphological specialisation toward myrmecophytism are assessed. The behavioural traits of Cladomyrma are compatible with traits exhibited by other protective plant-ants. This work demonstrates that all species of Cladomyrma investigated (dianeae, maschwitzi, yongi, petalae) confer antiherbivore protection to young leaves of its host. The ants also attack and repell or kill herbivorous insect larvae encountered on young foliage. Cleaning behaviour appears to be a trait shared by all members of the genus, and the two species tested (maschwitzi, petalae) successfully removed termite eggs experimentally placed onto young leaves. Another trait common to all known species of the genus is that the ants preferentially patrol young shoots and leaves ('neophily'). These behavioural traits of Cladomyrma likely reduce stem damage and pathogenic infection of their host. The ants prune encroaching vegetation (tested in dianeae maschwitzi, petalae, yongi, observed in crypteroniae) and attack paper tape used to mark host plants (observed in andrei, dianeae, hobbyi, nudidorsalis, maschwitzi, yongi, petalae). If these traits combined translate into a better reproductive success of the hosts has yet to be verified. Evidence for lifetime fitness benefits is particularly difficult to quantify for the long-lived woody host plants of Cladomyrma. The predominant food source of Cladomyrma appears to be the honeydew of scale insects (Coccidae and Pseudococcidae) which the ants tend inside their nest cavities. Observations on scale insect acquisition by Cladomyrma foundress queens show that hemipteran trophobionts are not transported by the queens on their nuptial flight but they nevertheless arrive on the host plant independently of the ants. Entry into nest chambers is facilitated by small holes kept open by the foundress queen. Most Cladomyrma species have been recorded from only one or two (three) host plant species (andrei, crypteroniae, hobbyi, maschwitzi, nudidorsalis, scopulosa, yongi), but two species, Cladomyrma petalae and C. dianeae, are more catholic in their host usage; the first being a 'generalist' plant-ant colonising hosts across a broad taxonomic range, the second inhabiting several members of the genus Neonauclea. First results of host-choice experiments with C. petalae are presented and the potential mechanisms promoting host specificity are discussed. My studies of the Cladomyrma/plant associations indicate that codiversification and host shifts or host expansions, rather than cospeciation, shape the pattern of species interactions in this system. Finally, I propose a scenario in which three key traits of Cladomyrma –access to live stems, utilisation of indirect food rewards via trophobionts and 'neophily'– are hypothesised to favour niche differentiation and the acquisition of new hosts over evolutionary time.
Global betrachtet, bestehen große Unterschiede in der menschlichen Entwicklungsfähigkeit sowohl zwischen verschiedenen Gruppierungen innerhalb einer Gesellschaft als auch zwischen unterschiedlichen Gesellschaften. Diese Differenzen bedürfen einer Begründung. Armut mit ihren Begleiterscheinungen Hunger, Unter- und Mangelernährung (Ernährungsunsicherheit) ist ein menschlich und individuell nicht wünschenswerter Zustand. Angemessene Ernährung ist der Grundstein für jegliche Form von Entwicklung. Armut ist ein absoluter Zustand, der die Betroffenen der Erfüllung grundlegender menschlicher Bedürfnisse und der vollwertigen Teilhabe an der Menschengemeinschaft beraubt. Um Armut als ungerecht verstehen zu können, muss sie von einer bestimmten Art (z.B. strukurell) oder Gründen sein. Biodiversität ist ein grundlegender Baustein, um den Fortbestand der Erde und der Menschheit zu sichern. Ohne biologische Vielfalt ist kurzfristig kein qualitativ hochwertiges und langfristig überhaupt kein Leben möglich. Diverse Regionen und gesellschaftliche Gruppierungen sind unterschiedlich stark von ihrer Nutzung für das alltägliche Überleben abhängig und von einem Verlust der (Agro-)Biodiversität betroffen. Biodiverse Ernährungsstrategien werden selten zur Verringerung der Unterernährung eingesetzt. Die Themen Recht auf Nahrung und landwirtschaftliche Vielfalt sind in dieser Form noch nirgends behandelt worden. Es gibt bislang keine normative Debatte bzw. Literatur, die eine moralphilosophische Begründung des Rechts auf Nahrung versucht und sie in Bezug zu relevanten Abkommen und Rechtskommentaren daraufhin untersucht, welche Gerechtigkeits-konzeptionen implizit und explizit vorhanden sind und inwiefern sie die strukturelle Dimension von Armut und Unterernährung thematisieren. Dies ist ein Versuch der partiellen Aufarbeitung, der sowohl normative als auch empirische Elemente enthält. Nach der umfassenden Analyse landwirtschaftlicher Strukturen sowie der strukturellen Bedingtheiten von Armut untersuche ich die Plausibilität der Begründungsoptionen eines sozialen Menschenrechts und prüfe im Anschluss ob sich Elemente einer moralischen Argumentation innerhalb des UN Sozialpakts, der Allgemeinen Anmerkung 12 des UN Wirtschafts- und Sozialrats sowie der Freiwilligen Leitlinien der FAO rechtfertigen lassen. Abschließend plädiere ich für eine vielfältige Landwirtschaft und die Hinwendung von Ernährungssicherungs-strategien zu biodiverser Ernährung.