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One of the key challenges of our era is to halt biodiversity loss and foster the sustainable use of nature. The Sustainable Development Goals (SDGs) recognize the importance of the inextricable link between social and ecological systems and human quality of life (QoL) and biodiversity. Therefore, understanding the feedback and interactions between biodiversity, nature’s contributions to people (NCP), and QoL plays a central role in advancing toward sustainability. In this context, the social-ecological systems (SES) approach has advanced on the subject, particularly in recent decades; however, much remains to be done to comprehensively understand these relationships and interactions, especially at local decision-making scales. In this thesis, through the lenses of the SES approach, I investigate connections between biodiversity, NCP, and QoL in a tropical dry forest (TDF) on the Western coast of Mexico. This place is one of the best-known Neotropical TDF and has been the focus of SES research in the past 20 years, making it an excellent case study for exploring these connections.
First, to approach the need for dialogue among different global and local scales and between global and local frameworks, the thesis identifies five key components of the SES dynamics-(1) ecological supply, (2) co-production of NCP, (3) management, (4) demand, and (5) benefits- and three local decision-making scales of analysis- individual plot, smallholder, and land tenure or governance units. A literature review was performed on the social-ecological indicators for the last 11 years in the Chamela-Cuixmala region to operationalize this framework. The representability of the framework shows that research has emphasized the components of NCP co-production (42% of indicators) and SES management (21%). By analyzing SES dynamics through this new framework, we can support the monitoring of NCP and potentially detect regime shifts or radical changes before they happen. The framework is simultaneously context-specific and operationable across global contexts, providing an opportunity to inform discussions on global sustainability from local contexts.
Second, this thesis uses social-ecological information to identify social-ecological systems units (SESU) spatially explicitly. A methodology was provided to spatially identify the components of social-ecological systems that environmental conditions and management practices have shaped at three previously stated relevant decision-making scales: plots owned by individuals, plot owners, and governance units. To do so, we identified and characterized: (1) ecological clusters (EC), (2) social-management clusters (SC), and (3) SESU in a TDF in western Mexico. Our findings suggested that decision-makers (ejidatarios, i.e., type of ownership (related to agrarian reform), that in most cases the land allocated is small-smallholders-) are bounded by the topographical characteristics and the public policies that determine communal (or private) governance and the number of resources available to them. The methodology can be applied to other contexts and nested decision-making scales. The spatial identification of these interdependencies is critical for landscape planning since it can contribute to reconciling productive activities and biodiversity conservation.
Finally, the thesis examines the self-perceived QoL across the different SESU, finding 48 QoL items, which were grouped into six categories: 1) social capital, 2) economic capital, 3) agency, 4) nature, 5) peasant non-work activities, and 6) government and services; and two additional dimensions referred to obstacles and enablers of QoL. We found that the more land cover transformation, the more enablers, and obstacles of QoL are identified; emphasis was put on economic capital to achieve QoL. As management is intensified and governance fosters individualism across SES, the higher the Current Welfare Index, and the lower the self-perceived material and non-material satisfaction. We discuss the need for governance structures promoting smallholders´ worldviews that move beyond utilitarianism and foster commons. The social-ecological systems approach employed throughout this dissertation contributed towards crosscutting insights; the testing of new frameworks and methodologies represent important steps towards unraveling the connections between biodiversity, NCP, and QoL and contributes to achieving sustainable scenarios such as the ones proposed by the SDGs.
This research report presents a transdisciplinary student research project on developing climate resilience of communities in Marine Protected Areas in the Lesser Antilles. For the second time, the Leuphana University Lüneburg and the Sustainable Marine Financing Programme (SMF) of the Deutsche Gesellschaft für internationale Zusammenarbeit (GIZ) partnered up. The first project on the Caribbean Island Dominica showed that community resilience is a complex concept that is not yet well understood. Building on these findings, this year’s project broadened the scope in addressing the effect of varying local conditions on climate resilience on four different Caribbean islands: Dominica, Grenada, St Lucia, and St. Vincent and the Grenadines. For the GIZ, the research project aimed at improving the understanding of the socio-ecological resilience framework for tackling problems of Marine Managed Areas (MMA) and Marine Protected Areas (MPA). Also, it enabled new thoughts on how the GIZ and other development agencies can more effectively assist island states to better cope with the challenges of climate change. The role of the students from the “Global Environmental and Sustainability Sciences” programme of Leuphana University included the design of four transdisciplinary research projects to study the effect of varying local conditions in disaster-prone regions in the Southern Caribbean on climate resilience. The developing island states in the Caribbean are extremely vulnerable to more frequent and intense natural hazards while relying on ecosystem services that are threatened by extreme weather events, in particular Hurricanes. After such adverse events, low economic stability leads to a dependency of the states on international assistance. To decrease the vulnerability to shocks, counteracting measures that encourage learning and adaptation can increase the resilience against extreme weather events and their consequences. Concepts that were considered during the design of the transdisciplinary research projects were the adaptation of systems, diversity and stakeholder participation and resilience-focused management systems. Building on the results from last year in Dominica, the establishment of a four islands design allowed for greater comparison to better understand community approaches to solve a concrete sustainability problem: securing livelihoods while protecting natural and cultural resources. The research methods of a literature review, stakeholder mapping, semi-structured interviews, scenario development and visioning were used in the projects. A comparison of the four TD projects revealed four overarching lessons. First, all countries recognise a need for restoration and conservation projects, i.e., nature-based solutions implemented and managed by the local community in the MPA. Furthermore, all four cases show that the limited participation of local people in the management and organisation of the MPA is a factor constraining community resilience. Third, this TD project highlights the importance to distinguish climate change as an event or as a process. When climate change occurs as a series of disaster events (e.g., hurricanes, floodings, and heatwaves) in combination with s gradual degradation of natural ecosystems (e.g., coral bleaching and ocean warming), people in MPA communities show highly adaptive and restorative behaviour. Finally, this project was an attempt to realize a cross-cultural and virtual transdisciplinary project. The research approach of transdisciplinarity links different academic disciplines and concepts, and non-scientific stakeholders are included to find solutions for societal and related scientific problems. A major learning was that in virtual TD projects particular attention needs to be paid to setting clear boundaries and be explicit about success criteria. Nonetheless, the findings of the projects provide valuable learning lessons to be applied in practice and that can prove useful for future research.
Biodiversity is quickly diminishing across the planet, primarily owing to human pressures. Protected areas are an essential tool for conserving biodiversity in response to increasing human pressures. However, their ecological effectiveness is contested and their capacity to resist human pressures differ. This dissertation aimed to assess the ecological effectiveness of different protection levels (from strict to less strictly protected: national park, game reserve, forest reserve, game-controlled area, and unprotected areas) in biodiversity (both mega diverse butterflies and mammals), maintaining habitat connectivity, and reducing anthropogenic threats at the wider landscape in the Katavi-Rukwa Ecosystem of southwestern Tanzania. To achieve this overarching goal, I employed an interdisciplinary approach.
First, I analyzed butterfly diversity and community composition patterns across protection levels in the Katavi-Rukwa Ecosystem. I found that species richness and abundance were highest in the game reserves and game-controlled areas, intermediate in the forest reserves, national park and unprotected areas. Species composition differed significantly among protection levels. Landscape heterogeneity, forest cover, and primary productivity influenced species composition. Land-use, burned areas, forest cover, and primary productivity explained the richness of species and functional traits. Game reserves hosted most indicator species.
Second, I modelled the spatial distribution of six large mammal target species (buffalo Syncerus caffer, elephant Loxodonta africana, giraffe Giraffa camelopardalis, hartebeest Alcelaphus buselaphus, topi Damaliscus korrigum, and zebra Equus burchellii) across environmental and protection gradients in the Katavi-Rukwa Ecosystem. Based on species-specific density surface models, I found relatively consistent effects of protection level and land-use variables on the spatial distribution of the target mammal species: relative densities were highest in the national park and game reserves, intermediate in forest reserves and game-controlled areas and lowest in un-protected areas. Beyond species-specific environmental predictors for relative densities, our results highlight consistent negative associations between relative densities of the target species and distance to cropland and avoidance of areas in proximity to houses.
Third, I examined temporal changes in land-use, population densities and distribution of six large mammal target species across protection levels between 1991 and 2018. During the surveyed period, cropland increased from 3.4 % to 9.6 % on unprotected land and from ≤0.05 % to <1 % on protected land. Wildlife densities of most, but not all target species declined across the entire landscape, yet the onset of the observed wildlife declines occurred several years before the onset of cropland expansion. Across protection levels, wildlife densities occurred at much greater densities in the national park and game reserves and lowest in the forest reserves, game-controlled areas and unprotected areas. Based on logistic regression models, target species preferred the national park over less strictly protection levels and areas distant to cropland. Because these analyses do not support a direct relationship between the timing of land-use change and wildlife population dynamics, other factors may account for the apparent ecosystem-wide decline in wildlife.
Fourth, I quantified land-use changes, modelled habitat suitability and connectivity of elephant over time across a large protected area network in southwestern Tanzania. Based on analyses of remotely-sensed data, cropland increased from 7% in 2000 to 13% in 2019, with an average expansion of 634 km2 per year. Based on ensemble models, distance from cropland influenced survey-specific habitat suitability for elephant the most. Despite cropland expansion, the locations of the modelled elephant corridors (n=10) remained similar throughout the survey period. According to ecological knowledge, nine of the modelled corridors were active, whereas one modelled corridor had been inactive since the 1970s. Based on circuit theory, I prioritize three corridors for protected area connectivity. Key indicators of corridor quality varied over time, whereas elephant movement through some corridors appears to have increased over time.
Overall, this dissertation underpins differences in ecological effectiveness of protected areas within one ecosystem. It highlights the need to utilize a landscape conservation approach to guide effective conservation across the entire protection gradient. It also suggests the need to enforcing land use plans and having alternative and sustainable forms for generating income from the land without impairing wildlife habitat.
Im Kontext der Problematik von Fehlinformationen in der populärwissenschaftlichen Literatur widmet sich diese Arbeit in einer Fallstudie drei häufig verkauften Büchern Peter Wohllebens. Untersucht wird, wie nah diese Werke sich am aktuellen Stand der Forschung orientieren und wie gut die getätigten Aussagen nachvollziehbar sind. Für die Untersuchung wurde der Inhalt der Bücher codiert und die resultierenden 8899 Codiereinheiten quantitativ und qualitativ-vergleichend analysiert. Ergänzt wurde dies durch die qualitativ-vergleichende Analyse von drei Schwerpunktthemen. Aus den Ergebnissen wird geschlussfolgert, dass Wohllebens Nähe zum wissenschaftlichen Diskurs unter Einschränkungen ausreichend und die Nachvollziehbarkeit seiner Aussagen mangelhaft ist. Basierend auf diesen Erkenntnissen werden mögliche Maßnahmen und Handlungsfelder für eine Erhöhung der wissenschaftlichen Qualität populärwissenschaftlicher Werke diskutiert. Es werden weitere potentielle Forschungsmöglichkeiten für ein besseres Verständnis der Situation in den Populärwissenschaften identifiziert und vorgeschlagen.
Neben den von Hathaway aufgeführten Folgen der industriellen Landwirtschaft, lassen sich außerdem weltweit degradierte Böden, massives Artensterben und ein zunehmender anthropogener Klimawandel verzeichnen. Infolgedessen lassen sich ebenso Auswirkungen auf die soziale Sphäre feststellen, beispielsweise negative Einflüsse auf die menschliche Gesundheit und die ungleiche globale ökonomische Gewinnverteilung. Um diesen Trend zu brechen, muss Landwirtschaft neu gedacht und transformiert werden. Dafür bedarf es innovativer und vor allem nachhaltiger Landnutzungskonzepte, die eine zukunftsfähige Lebensmittelproduktion gewährleisten. In diesem Kontext ist die Sicherstellung der nachgefragten Produktmengen ebenso relevant, wie ein ökologischer Beitrag für gesündere Böden, für die Förderung der Artenvielfalt, die Speicherung von Kohlenstoff und für ein intaktes Klimageschehen. Gleichzeitig sollte das Ziel sein, dass die Landwirt*innen gut von ihrer Arbeit leben können.
Einen Beitrag zu einem solchen zukunftsfähigen Landnutzungskonzept können Waldgärten leisten. Dabei handelt es sich um mehrschichtige Systeme, welche multifunktional die natürliche Struktur von Wäldern und Waldrändern imitieren. Auf diese Weise können verschiedene Funktionen erfüllt werden, wie beispielsweise die Produktion von vielfältigen Lebensmitteln. Bisher ist das Konzept des Waldgartens in Deutschland noch nicht weit verbreitet. Es wurde bisher wenig wissenschaftliche Forschung auf dem Gebiet betrieben und in Deutschland existieren bisher nur wenige Waldgärten. In anderen Ländern bestehen hingegen schon länger erste Erfahrungen oder auch schon lange Traditionen mit Waldgärten.
Im Folgenden wird die Fallstudie Hof an den Teichen vorgestellt, zusammengefasst welche Vorarbeiten bereits stattgefunden haben und das Forschungsziel und die Forschungsfragen hergeleitet.
This research report presents a transdisciplinary student research project on the development of climate resilience of communities on the Caribbean Island Dominica.
The research was conducted through a partnership between the Leuphana University Lüneburg and the Sustainable Marine Financing Programme (SMF) of the GIZ.
For the GIZ, the research project aimed at improving the understanding of the socio-ecological resilience framework for tackling problems of Marine Managed Areas and Marine Protected Areas. Also, it enabled new thoughts on how the GIZ and other development agencies can more effectively assists island states to better cope with the challenges of climate change.
The role of the students from the “Global Environmental and Sustainability Sciences” programme of Leuphana University included the design of four transdisciplinary research projects to research aspects of resilience of Caribbean communities.
The developing island states in the Caribbean are extremely vulnerable to more frequent and intense natural hazards while relying on the ecosystem services that are also at risk from extreme weather events, in particular Hurricanes. Low economic stability leads to a dependency of the states on international assistance. To decrease the vulnerability to shocks, counteracting measures that encourage learning and adaptation can increase the resilience against extreme weather events and their consequences.
Concepts that were considered during the design of the transdisciplinary research projects were the adaptation of systems, diversity and stakeholder participation and resilience-focused management systems. Also, the students critically assessed the concept of foreign aid and how it can be successful, mitigating the risk of introducing neo-colonial structures. Flood Management, Biodiversity, Small-Scale Agriculture and Foreign Aid on Dominica were the topics of the transdisciplinary projects. The research methods of a literature review, stakeholder mapping, interviews, scenario development and visioning were used in the projects.
In four scenarios developed in the ‘Flood Management’ project, it became evident that a broad as well as coordinated stakeholder engagement and a variety of measures are required for community resilience. A key finding of the ‘Biodiversity’ project was the identity dimension of community resilience, underlining the importance of the relationship between individuals and nature. The interlinkage of social identity processes and a resilient disaster response was also stressed by the project ‘Foreign Aid’, which highlighted that financial support is similarly important to inclusivity and reflexivity in the process of resource distribution. To recover from extreme weather events, the social memory also plays an important role. The project on ‘Small-scale Agriculture’ concluded, that the memory-making of local communities is as vital to community resilience as formal plans and trainings.
The research project was based on the research approach of transdisciplinarity because of its solution-orientation. It links different academic disciplines and concepts, and non-scientific stakeholders are included to find solutions for societal and related scientific problems. In the four projects, principles of transdisciplinary research were party applied, but some challenges arose due to the geographical distance, time constraints and a strong focus on the scientific part in some phases. Nonetheless, the findings of the projects provide valuable learning lessons to be applied in practice and that can prove useful for future research.
Assessment of forest functionality and the effectiveness of forest management and certification
(2021)
Forest ecosystems are complex systems that develop inherent structures and processes relevant for their functioning and the provisioning of ecosystem services that contribute to human wellbeing. So far, forest management focused on timber production while other services were less rewarded. With increasing climate change impacts, especially regulating ecosystem services such as microclimate regulation are ever more relevant to maintain forest functions and services. A key question is how forest management supports or undermines the ecosystems’ capacity to maintain those functions and services. Forest management implies silvicultural interventions such as thinning and timber harvesting and ranges from single tree extraction to large clearcuts as well as forest reserves without active forest operations and shape the character of forest ecosystems (e.g. natural versus planted forests). Artificial plantings, monocultures and management for economic timber production simplify forest structures and impair ecosystem resilience, resistance and the existence of forests but also the services essential for the prosperity and health of humanity. Efforts to reduce the negative impacts and attempts to safeguard forest functions are manifold and include compulsory national and international guidelines and regulations for forest management, conventions, but also voluntary mechanisms such as certification systems.
The main objective of this thesis was the development of a concept to assess the functionality of forests and to evaluate the effectiveness of forest ecosystem management including certification. An ecosystem-based and participatory methodology, named ECOSEFFECT, was developed. The method comprises a theoretical and an empirical plausibility analysis. It was applied to the Russian National FSC Standard in the Arkhangelsk Region of the Russian Federation – where boreal forests are exploited to meet Europe's demand for timber. In addition, the influence of forestry interventions on temperature regulation in Scots pine and European beech forests in Germany was assessed during two extreme hot and dry years in 2018 and 2019.
Microclimate regulation is a suitable proxy for forest functionality and can be applied easily to evaluate the effectiveness of forest management in safeguarding regulating forest functions relevant under climate change. Microclimate represents the most decisive factor differentiating clearcuts and primary forests. Thus, the assessment of forest microclimate regulation serves as convenient tool to illustrate forest functionality. In the boreal and temperate forests studied in the frame of this thesis, timber harvesting reduced the capacity to self-regulate forests’ microclimate and thus impair a crucial part of ecosystem functionality. Changes in structural forest characteristics influenced by forest management and silviculture significantly affect microclimatic conditions and therefore forest ecosystems’ vulnerability to climate change. Canopy coverage and the number of cut trees were most relevant for cooling maximum summer temperature in pine and beech forests in northern Germany. Maximum temperature measured at ground level increased by 0.21 – 0.34 K when 100 trees were cut. Opening the forest canopy by 10 % caused an increase of maximum temperature at ground-level by 0.53 K (including pine and beech stands). Relative temperature cooling capacity decreased with increasing wood harvest activities and dropped below average values when more than 656 trees per hectare (in 2018; and 867 trees in 2019) were felled. In pine stands with a canopy cover below 82 % the relative temperature buffering capacity was lower than the average. Mean maximum temperature measured at ground-level and in 1.3 m was highest in a pine-dominated sample plots with relatively low stand volume (177 m3 ha-1) and 9 K lower in a sample plot with relatively high stock volumes of F. sylvatica (> 565 m3 ha-1). During the hottest day in 2019, the difference in temperature peaks was more than 13 K for pine-dominated sample plots with relatively dense (72 %) and low (46 %) canopy cover.
The Russian FSC standard has the potential to improve forest management and ecological outcomes, but there are shortcomings in the precision of targeting actual problems and ecological commitment. In theory, FSC would transform forest management practices and induce positive changes and effective outcomes by addressing 75 % of the identified contributing factors including highly relevant factors and threats including large-scale (temporary) tree cover loss, which contributes to reducing about half of the identified stresses in the ecosystem. It is theoretically plausible that FSC prevents logging in high conservation value forests and intact forest landscapes, reduces the size and number of clearcuts, and prevents hydrological changes in the landscape. However, the standard was not sufficiently explicit and compulsory to generate a strong and positive influence on the identified problems and their drivers. Moreover, spatial data revealed, that the typical regular clearcut patterns of conventional timber harvesting continue to progress into the FSC-certified boreal forests, also if declared as ‘Intact Forest Landscape’. This results in the need to verify the assumptions and postulates on the ground as it remains unclear and questionable if functions and services of boreal forests are maintained when FSC-certified clearcutting continues. On the clearcuts, maximum temperature exceeded 36 °C and stayed below 30 °C in the closed primary forest. The number of days with temperatures above 25 °C at least doubled on clearcuts. Temperature cooling capacity was reduced by up to 14 % and temperature buffering capacity up to 60 %. The main reason why FSC-certified clearcuts do not differ from conventional clearcuts is that about 97 % of trees within equally large clearcut sites of up to 50 ha were removed. The spatial design of clearcuts, their size and the intensity of clearing as well as the density of skidding trails for timber extraction was not positively influenced by FSC-certification. Annual tree cover loss was lowest in non-certified areas. This means, that FSC may even contribute to an increased biomass removal within the clearcuts, which compromises the ecosystems’ capacity to recover and maintain ecological functions and services. The analysis of satellite-based data on tree cover loss showed that clearcutting causes secondary dieback in the surrounding of the cleared area. FSC-certification does not prevent the various negative impacts of clearcutting and thus fails to safeguard ecosystem functions. The postulated success in reducing identified environmental threats and stresses, e. g. through a smaller size of clearcuts, could not be verified on site. The empirical assessment does not support the hypothesis of effective improvements in the ecosystem. In practice, FSC-certification did not contribute to change clearcutting practices sufficiently to effectively improve the ecological performance. Sustainability standards that are unable to translate principles into effective outcomes fail in meeting the intended objectives of safeguarding ecosystem functioning. Clearcuts that carry sustainability labels are ecologically problematic and ineffective for the intended purpose of ecological sustainability.
The overexploitation of provisioning services, i.e. timber extraction, diminishes the ecosystems’ capacity to maintain other services of global significance. It also impairs ecosystem functions relevant to cope with and adapt to other stresses and disturbances that are rapidly increasing under climate change.
Forest management under climate change needs to apply precautionary principles and reduce further ecological risks such as secondary dieback and deterioration of regulating services that are relevant for the functioning of forests. Forest managers have to avoid ecological disimprovements by applying strict ecological principles with effective outcomes in order to maintain functional forests that regulate their own microclimate also as a basis for sustainable economic benefits.
Global environmental changes and the subsequent biodiversity loss has raised concerns over the consequences for the functioning of ecosystems and human well-being. This thesis provides new mechanistic insights into the role of tree diversity in regulating forest productivity and forests’ responses to climate change. The thesis also addresses the overlooked functional role of ecological continuity in mediating ecosystem processes in the context of multiple global environmental changes. The findings of the thesis emphasize the need to retain the functional integrity of forest ecosystem by preserving biodiversity and acknowledging the ecological memory forests.
Summary
Since the early 2000s, ecosystem services strongly gained significance as a research topic. While the number of papers strongly increased, the concept was further developed which changed the way it was applied. From highlighting the value of ecosystems by viewing them not only from an ecological, but also from an economic perspective in the beginning, it is nowadays, among others, used to map and calculate the monetary value of ecosystem services. Lately, the International Panel on Biodiversity and Ecosystem Services (IPBES) further developed the concept into Nature’s contributions to people (NCP) which puts a stronger emphasis on stakeholders and indigenous knowledge.
However, so far none of the conceptual developments managed to integrate the temporal dimension of ecosystem services into this concept, although this should be the basis for a sustainable long-term management of ecosystems and their services.
Therefore, I present three articles in this thesis that deal with temporal aspects of ecosystem services. In two of them I also present a proposal for a framework for the classification of ecosystem services based on their temporal dynamics.
In this dissertation I differentiate between two types of temporal aspects, both of which have in common that change takes place over a certain period of time. The concepts of transformation, transition and regime shift are used to describe changes in social or ecological systems as a whole, for example the transformation towards a more sustainable society. The temporal dynamics that I present, on the other hand, relate to the temporal changes in ecosystem services themselves.
The first article focuses on how the literature on ecosystem services incorporates social and ecological change, illustrated by the concepts of transformation, transition, and regime shift. The second and third articles deal with the temporal dynamics of ecosystem services. While the second article presents a preliminary framework for categorizing the temporal dynamics of ecosystem services, the third article uses this framework to test how the temporal dynamics of ecosystem services are represented in the literature.
Based on the insights from the three articles, I conclude that most of the studies on ecosystem services only focus on one point in time. One reason for this is that most studies are conducted over a maximum of a four-year time span which does not allow to monitor dynamics over longer time spans. In most articles that do account for temporal aspects, the focus is strongly on the side of ecological supply of ecosystem services rather than on the demand-side which leads to the exclusion of stakeholder perceptions and therefore, makes it impossible to connect ecosystem service demand and supply over time. Moreover, the concept of change that is used most often in the literature is that of regime shifts which comes from a purely ecological background and focuses mostly on changes that happened in the past. This neglects the possibility of change towards a positive outcome in the future. In general, there is a strong disciplinary divide in the concepts and terminology used. This leads to a lack of exchange between different scientific disciplines and non-academic stakeholders. Approaches that are needed to solve problems of ecosystem service management are therefore impeded.
To enable future research to better account for temporal aspects and connect supply and demand sides of ecosystem services with each other, I give four recommendations for future research. These are (I) take temporal dynamics into account by conducting long-term research, (II) ensure conceptual clarity, (III) create a solution-oriented agenda and (IV) take the demand side into account by involving stakeholders’ perceptions over time.
By following these recommendations, future research could help to support the sustainable management of ecosystem services as dynamics will be better known and targeted measures can be implemented.
Tropical forests worldwide support high biodiversity and contribute to the sustenance of local people’s livelihoods. However, the conservation and sustainability of these forests are threatened by land-use changes and a rapidly increasing human population. In this dissertation, I focused on the effects of land-use change on forest biodiversity in the rural landscapes of southwestern Ethiopia, against a backdrop of human population growth. These landscapes are being progressively degraded, encroached and fragmented as a result of different pressures, including the intensification of coffee production, farmland expansion, urbanization and a growing rural population. Understanding the drivers of biodiversity loss and the responses of biodiversity to such pressures is fundamental to direct conservation efforts in these tropical forests.
This dissertation aimed to characterize biodiversity patterns in the moist Afromontane forests of southwestern Ethiopia and to examine how biodiversity patterns are affected by land-use and land-use changes (mediated by coffee management intensity, landscape attributes and housing development) in a context of a rapidly growing rural population. To achieve this goal, I take an interdisciplinary approach where, first, I examined the effects of coffee management intensity on diversity patterns of woody plants and birds, spanning a gradient of site-level disturbance from nearly undisturbed forest interior to highly managed shade coffee forests. Results showed that specialized species of woody plants (forest specialists) and birds (forest specialists, insectivores and frugivores) were affected by coffee management intensity. The richness of forest specialist trees and the richness and/or abundance of insectivores, frugivores and forest specialist birds decrease with increasing levels of disturbance. Second, I investigated the effects of landscape context on woody plants, birds and mammals. Community composition and specialist species of woody plants and birds were sensitive to landscape context, where woody plants responded positively to gradients of edge-interior and birds to gradients of edge-interior and forest cover. Further results showed that a diverse mammal community, with 26 species, occurs at the forest edge of shade coffee forests and that the leopard, an apex predator in the region depended on large areas of natural forest. A closer examination of leopard activity patterns revealed a shift in the diel activity as a response to human disturbance inside the forest, further highlighting the importance of natural undisturbed forests for leopards in the region. Together, these findings demonstrate the value of low managed shade coffee forests for biodiversity, and importantly, emphasize the irreplaceable value of undisturbed natural forests for biodiversity. Third, I investigated the effects of prospective rural population growth (mediated by housing development) on the forest mammal community. Here, population growth was projected to negatively influence several mammal species, including the leopard. Housing development that encroached the forest entailed worse outcomes for biodiversity than a combination of prioritized development in already developed areas and coffee forest protection. Fourth, to understand the motivations behind high human fertility rates in the region, I examined the determinants of women fertility preferences, including their perceptions on social and biophysical stressors affecting local livelihoods such as food insecurity and environmental degradation. Fertility preferences were influenced by underlying social norms and mindsets, a perceived utilitarian value of children and male dominance within the household, and were only marginally affected by perceptions of social and biophysical stressors. Results further indicated a mismatch between the global discourse on the population-environment-food nexus and local perceptions of this issue by women. My findings suggest the need for new deliberative and culturally sensitive approaches that engage with pervasive social norms to slow down population growth.
Overall, this dissertation demonstrates the key value of moist Afromontane forests in southwestern Ethiopia for biodiversity conservation. It indicates the need to promote coffee management practices that reduce forest degradation and highlights that high priority should be given to the conservation of undisturbed natural forests. It also suggests the need to integrate conservation goals with housing development in landscape planning. A promising approach to achieve the above conservation priorities would be the creation of a Biosphere Reserve and to promote the ecological connectivity between the larger forest remnants in the region. Finally, this dissertation demonstrates the importance of placed-based holistic approaches in conservation that consider both proximate and distal drivers of forest biodiversity decline.
Die Kulturlandschaft im Alpenraum war in den letzte Jahrzehnten einem besonders starken Strukturwandel ausgesetzt. Als Region mit einem hohen Anteil an Grenzertragsstandorten lassen sich hier zwei gegenläufige Entwicklungen feststellen: zum einen findet eine Intensivierung der Landnutzung in Bereichen mit guter Zugänglichkeit und maschineller Nutzbarkeit statt, zum anderen kommt es häufig zu einem Rückgang der Nutzungsintensität oder Nutzungsaufgabe in Bereichen, in denen die landwirtschaftliche Bearbeitung schwierig ist. Die Auswirkungen auf die Biodiversität werden bei beiden Entwicklungen kritisch gesehen, allerdings mangelt es an detaillierten Untersuchungen.
Im Rahmen eines sechsjährigen Forschungsvorhabens wurden auf einer Weidefläche in den Allgäuer Alpen Laufkäfer, Spinnen und Vegetation untersucht. Auf der Fläche fand zu Beginn der Untersuchung eine Nutzungsänderung statt: ein großer Teil der vormals intensiv von Schafen beweideten Fläche wurde auf extensive Rinderbeweidung umgestellt, kleine Teilflächen wurden aus der Nutzung genommen.
Der Fokus dieser Dissertation liegt in den Untersuchungen der Laufkäfer. Hier wurde zunächst ein Erfassungsschema für Laufkäfer in schwer erreichbaren Gebieten der Alpen erarbeitet, um intensive und mehrjährige Untersuchungen logistisch durchführen zu können. Dabei wurden die Ergebnisse der Laufkäfererfassung über die gesamte Vegetationsperiode mit den Ergebnissen einer reduzierten Erhebung verglichen. Es konnte gezeigt werden, dass eine Beprobung über jeweils zwei Wochen Anfang Juni und Anfang Juli den gesamten Datensatz hinreichend repräsentiert.
Des weiteren wurde untersucht, ob die Vegetation als Surrogat für die beiden untersuchten Arthropodengruppen (Spinnentiere und Laufkäfer) dienen kann, d.h. die Ergebnisse der Vegetation auf die anderen Artengruppen übertragbar ist. Dies wurde sowohl auf Ebene der Artzusammensetzung als auch des Artenreichtums für die drei Taxa geprüft. Zudem wurde überprüft, ob die unter vegetationskundlichen Aspekten abgegrenzten geschützten Lebensraumtypen auch besonders wertvolle Habitate für die Arthropodengruppen darstellen. Die Ergebnisse der Untersuchung zeigen, dass eine ausreichende Kongruenz nicht gegeben und damit die Übertragbarkeit von Ergebnissen bei der Vegetation auf die untersuchten Arthropodengruppen in den Gebirgslebensräumen nicht gewährleistet ist. Dies hat eine hohe praktische Relevanz, da im Rahmen von Managementplanungen für die FFH-Richtlinie als auch bei der Bayerischen Alpenbiotopkartierung überwiegend ein starker Fokus auf vegetationskundlichen Aspekten liegt und insbesondere artenreiche Arthropodengruppen meist nicht betrachtet werden.
Abschließend wurde mittels gemischter Modelle (mixed effects models) untersucht, welche Veränderungen bei den Laufkäfern nach der Nutzungsänderung im Untersuchugnsgebiet auftraten. Sämtliche errechneten Modelle zeigten Veränderungen der abhängigen Variablen über die Zeit: nach Aufgabe der intensiven Schafbeweidung nahmen die Arten- und Individuenzahlen sowie die Biomasse an Laufkäfern zu. Die Tiere wurden durchschnittlich größer und es traten mehr herbivore Laufkäfer auf. Auch konnten unterschiedliche Entwicklungen zwischen den Standorten beobachtet werden. Die beobachteten Veränderungen werden im Artikel detailliert diskutiert. Die meisten Veränderungen, insbesondere die Zunahme der Artenzahlen sowie der durchschnittlichen Körpergröße, deuten auf eine Erholung der Laufkäferfauna von der intensiven Schafbeweidung hin. Die Nutzungsumstellung und die aktuell praktizierte extensive Rinderbeweidung werden im Gebiet naturschutzfachlich positiv bewertet. Die Arbeit liefert eine gute Vorlage und fundierte Begründung, gerade auch im Alpenraum verstärkt Laufkäfer bei der Beantwortung naturschutzfachlicher Fragestellungen einzubinden.