Die Struktur und die strukturelle Komplexität von Wäldern beeinflussen zahlreiche wichtige Eigenschaften von Waldökosystemen, sowie auch deren Funktionen und Dienstleistungen, wie beispielsweise die Ökosystemstabilität, die Erhaltung der Biodiversität und die Kohlenstoffspeicherung. Die Bewirtschaftung von Wäldern verändert deren räumliche Struktur und übt somit auch einen Einfluss auf viele Leistungen und Funktionen von Waldökosystemen aus. In diesem Zusammenhang wird häufig diskutiert, ob Forstwirtschaft sich vereinfachend oder sogar fördernd auf die strukturelle Komplexität eines Waldbes...
Context Tropical ecosystems are widely recognised for their high species richness and outstanding concentrations of rare and endemic species. Previous studies either focussed on the effects of deforestation or climate change, whereas studies on the combined effects of these two major threats are limited.
Aims This research aimed to model current and future distributions of medium- to large-sized mammal species on the basis of different land-use and climate-change scenarios in 2050 and to assess whether the predicted effects of land-use change are greater than those of climate change and whether the combined effects of these drivers are greater than those of either individual driver.
Methods The present article demonstrates a method for combining nationwide wildlife-inventory data, spatially explicit species-distribution models, current and predicted future bioclimatic variables, other biophysical factors and human disturbance to map distributions of mammal species on the basis of different land-use and climate-change scenarios and to assess the role of protected areas in conservation planning.
Key results Seventeen medium- to large-sized mammal species were selected for modelling. Most selected species were predicted to lose suitable habitat if the remaining forest cover declines from the current level of 57% to 50% in 2050. The predicted effects of deforestation were stronger than the effects of climate change. When climate and land-use change were combined, the predicted impacts were more severe. Most species would lose suitable habitat and the average shift in species distribution was greater than 40%.
Conclusions The predicted effects were positive for only a few species and negative for most species. Current and future centres of mammal-species richness were predicted in large and contiguous protected forests and the average contribution of existing and proposed protected areas in protecting the focal species will increase from 73% to 80% across all scenarios.
Implications The present research advances the current understanding of the ecology of 17 medium- to large-sized mammal species with conservation relevance and the factors that affect their distributions at the landscape scale. In addition, the research demonstrated that spatially explicit models and protected areas are effective means to contribute to protection of mammal species in current and future land-use and climate-change scenarios.
Land-use change and intensification have a substantial impact on tropical mountain ecosystems worldwide. However, our understanding of how anthropogenic changes affect different facets of tree diversity and community composition as well as ecosystem functioning along elevational gradients remains limited. Therefore, the main objective of my doctoral dissertation was to examine how interactive effects of elevation and forest-use intensity impact tree species diversity, community composition, functional diversity, functional redundancy and forest structure patterns along an elevational gradie...
The combined effects of global warming and land-use conversion to human-modified systems are threatening biodiversity and ecosystem processes maintained by tropical mountains. To assess and predict the impact of global change on these ecosystems, it is crucial to understand the drivers and mechanisms of biodiversity and ecosystem processes. For instance, the study of carbon (C) and nitrogen (N) cycles is of key importance, as they encompass fundamental ecosystem processes such as carbon sequestration and storage, fluxes of C and N among ecosystem components as well as soil nitrogen turnover...
Land-use transitions can enhance the livelihoods of smallholder farmers but potential economic-ecological trade-offs remain poorly understood. Here, we present an interdisciplinary study of the environmental, social and economic consequences of land-use transitions in a tropical smallholder landscape on Sumatra, Indonesia. We find widespread biodiversity-profit trade-offs resulting from land-use transitions from forest and agroforestry systems to rubber and oil palm monocultures, for 26,894 aboveground and belowground species and whole-ecosystem multidiversity. Despite variation between ecosystem functions, profit gains come at the expense of ecosystem multifunctionality, indicating far-reaching ecosystem deterioration. We identify landscape compositions that can mitigate trade-offs under optimal land-use allocation but also show that intensive monocultures always lead to higher profits. These findings suggest that, to reduce losses in biodiversity and ecosystem functioning, changes in economic incentive structures through well-designed policies are urgently needed.
