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Worldwide declines in wild pollinators are threatening the provision of vital pollination functions and services to both native plant communities and crops. Habitat loss due to human land use changes is identified as one of the main drivers of wild bee decline. Particularly, farmland abandonment and conversion of natural forests into even-aged managed stands have greatly reduced the availability of essential early successional habitats in the landscape. In recent decades, to mitigate the loss of native biodiversity, there has been a growing interest in the conservation management of human modified landscapes. Modified landscape features, such as power-line clearings, can provide valuable alternative habitats for early successional plant species, which in turn offer important flower resources for wild bees. The main objectives for the four studies in this thesis were to study the conservation value of power-line clearings as habitat for insect-pollinated plant and wild bee communities in forest landscapes and to identify effects of different maintenance learing practices. We carried out a large-scale field experiment and an observational study in power-lines clearings. In the first three papers, we studied the experimental treatment effects on insectpollinated plant (forbs, shrubs, and dwarf shrubs) (Paper I), solitary bee (Paper II) and bumble bee (Paper III) communities in response to different vegetation clearing practices (treatments), where woody vegetation was: (i) cut, with woody debris left to decay; (ii) cutremove, with woody debris removed; and (iii) uncut. To study the effects of management practices we used different combinations of taxonomic and functional trait diversity indices or traits groups. We assessed the modifying influence of environmental conditions, and whether the treatment effects were maintained three years post-treatment (Paper I, II, III). In Paper II and III, we used the floral resources from Paper I as important explanatory factors for the wild bee communities. To identify the value of power-line clearings as a pollinator habitat in boreal production forests, we carried out an observational study on bumble bees (Paper IV). We studied the spatiotemporal variation in bumble bee richness and abundance between open habitats in power-line clearings and adjacent forest habitats throughout one foraging season, related to environmental conditions. Overall, the studies presented in this thesis show that power-line clearings can be important habitats for communities of both insect-pollinated plants and wild bees, and that habitat quality can be enhanced with proper management. We found that cutting the vegetation had a positive effect on plants and wild bees compared to the uncut plots, regardless of woody debris removal (Paper I, II, III). However, the effect of management practices was context dependent. Under certain environmental conditions the removal of woody debris led to a higher richness and functional diversity of plants (Paper I) which promoted a higher functional diversity of wild bees (Paper II, III). For solitary bees, woody debris removal promoted a strong positive effect which was sustained three years after cutting. Bumble bees seemed to thrive in both cut treatments. We found that the powerline clearings are valuable open canopy habitats for bumble bees in managed forests and that the power-line clearings provide essential late-season foraging resources, particularly heather (Calluna vulgaris) (Paper IV). In forest landscapes, power-line clearings can function as alternative habitats for wild bees in boreal forests and species associated with semi-natural habitats, providing potential nesting substrates and enhanced native flower resources. To improve habitat conditions for the solitary bees, removing the woody debris is highly recommended, whereas to improve habitat conditions for bumble bees, woody debris removal is beneficial, but not as important. Implementation of management efforts should be carefully located to areas of certain environmental conditions to achieve the best possible effect. Additionally, targeted enhancement of flower species with high nectar content or flowers with late phenology (i.e. heather), would further enhance the conservation value. Our results also highlight the importance of open habitats in managed forests and that less dense forest stands are important for wild bee conservation. To conserve native plants and wild bees species, the populations need to be maintained at a landscape level. Hence, management practices should be implemented in areas enabling connectivity between open semi-natural habitats in the landscape. Recommendations for overall wild bee conservation would thus be to implement a mosaic of woody debris retention and removal in power-line clearings, to support diverse wild bee communities. Together, the findings of this thesis represent a foundation for developing pollinator-friendly management strategies in power-line clearings in forest landscapes and suggest how power-line clearings should be included in integrated conservation plans.

In recent years, structural components such as woody species richness, diversity, canopies and non-woody lifeforms in tropical forests and woodlands have experienced increasing rates of degradation and deforestation due to agricultural expansion and other land use changes. The decline in plant species diversity in forests and woodlands has negative effects on ecosystem processes and functions such as atmospheric carbon sequestration and mitigations of global climate changes. However, our knowledge on how varieties of structural components interacts with physiographic conditions and anthropogenic disturbances to influence ecosystem processes are limited. This knowledge gap has consequently undermined our understanding of the potential contributions of structural components in enhancing human wellbeing. This thesis consist of series of studies from a moist forest and miombo woodlands in Tanzania. The main aim was to relate structural components, such as tree species richness, canopy, carbon stocks and their interactions, with physiographic conditions, and anthropogenic disturbances. I explore (1) how do tree species richness relates to vertical heterogeneity, mean and depth specific soil nutrient availability. (2) do dominant tree species influence the richness, diversity, evenness and vertical structure heterogeneity of non-dominant tree species? (3) how do tree canopy characteristics relates to herbaceous biomass and tree species richness? (4) how do the aboveground carbon stocks of trees relate to tree species richness, diversity and evenness along gradients of physiographic conditions and anthropogenic disturbances? Using data from vegetation and soil surveys in a series of regression analyses, I showed that variation in tree species richness were better explained by mean than vertical heterogeneity in soil nutrient availability in moist forest, while in miombo woodlands, vertical heterogeneity explained a large part of the variations in tree species richness than mean soil nutrient availability. Nondominant tree species richness, Shannon diversity and evenness had negative linear and nonlinear relationships with the relative abundance of dominant tree species in wet and dry miombo woodlands. Moreover, tree species structure, physiographic conditions and anthropogenic disturbances explained over 50 % of the variations in leaf area index (LAI) and nearly 20 % of the variations in aboveground herbaceous biomass (AGBH) in moist forest and miombo woodlands. Furthermore, aboveground carbon stocks of trees were unimodal, positive or negative linearly related to tree species richness, evenness and abiotic factors in the two vegetation types. X The relationships between structural components, physiographic conditions and anthropogenic disturbances has consequences on ecosystem properties such as carbon storage and sequestration, and biodiversity. Understanding of how structural components interact with environmental conditions and anthropogenic disturbances is a step towards establishing the potential contributions of forest and woodlands to local livelihoods. Thus, management of forests and woodlands in Tanzania require strategies that maintains the existing structural complexity. CCIAM

Fuelwood is the primary energy source for cooking in rural India. Natural forests in protected areas are often accessed by local people to collect this resource. However, the extraction of wood destructs forests, threatens species diversity and may lead to a loss of ecosystem functions. An approach to reduce the anthropogenic pressure on protected areas is to replace the amount of fuelwood harvested from natural forests with fuelwood obtained from alternative sources like home gardens. The aim of the study was to find out, if the livelihoods of local people could be improved and, if home gardens had the potential to function as substituting fuelwood sources, in order to reduce the extraction of fuelwood harvested from the Manas National Park (MNP) in Assam, India. Furthermore, it was investigated how the amount of fuelwood obtained from home gardens could be increased and, if the extent of the dominant cash-crop areca palm (Areca catechu) had a decreasing impact on the fuelwood supply by home gardens. Socio-economic household interviews were conducted, and the size of home gardens, as well as an inventory of potential fuelwood trees and of areca palms in home gardens was analyzed. Fuelwood harvests from the MNP decreased with the degree of education of household members and the access to an electric power source. Assamese people encroached the MNP to extract fuelwood more, than members of the aboriginal Bodo tribe. Households located closer to the nearest entry of the MNP, had a higher probability to procure fuelwood from the MNP, compared to households further away from the park. The more fuelwood was procured from home gardens, the less likely it was for households to rely on fuelwood obtained from the MNP. The proportion of fuelwood harvested from home gardens increased with the existing fuelwood stock and with the size of home gardens. The extent of the dominant monocultured areca palm (Areca catechu) did not have a negative effect on the amount of fuelwood supplied by home gardens. This study shows that the degradation of the MNP could be reduced by improving the livelihoods of local people through providing electricity and enhancing the general education. Conservation strategies like afforestation actions could increase the fuelwood stocks in home gardens and conservation education could raise community awareness towards the MNP and towards the potential of private fuelwood stocks. M-ECOL

Patches of high quality resources are important in many African savannahs. A source of this heterogeneity are mounds build by termites (termitaria). The soils and vegetation of termitaria have in many cases been found to be richer in important nutrients, and many studies have shown that termitaria are browsing hotspots for ungulates and megaherbivores. In 2015, 15 Rothchild’s giraffes (Giraffa camelopardalis rothschildi) were translocated to Lake Mburo National Park in Uganda. I conducted a study to explore to what extent giraffes utilize termitaria vegetation. The giraffe’s diet was observed in the dry season from June to August, as well as sampling the vegetation of the study area. Vegetation samples were taken along the feeding transect of the giraffes, perpendicular to the feeding transect, and randomly within the study area. The giraffe’s diet preference was analysed in relation to the vegetation available to the giraffes on and off termitaria. Giraffe’s were found to browse mainly on savannah vegetation consisting of Acacia gerrardii and other Acacia, and browsed on termitaria vegetation less than expected. The composition of species browsed on and off termitaria was found to be significantly different from eachother, with some overlap. Rhus natalensis and Carissa spinarum were browsed more than expected on termitaria, with R. natalensis being the most browsed species on termitaria, while C. spinarum had few browsing observations and bites associated with it. As the dry season progressed, the giraffes showed increased preference for termitaria vegetation in general, as well as R. natalensis. This study shows that for the giraffes of Lake Mburo National Park, while termitaria vegetation is utilized less than expected, it may be an important contributor to diet variability. M-ECOL

Wildlife translocations are a contentious practice that is on the rise. Wildlife rescue and release centers are one of the largest practitioners of translocation, but are often overlooked by the scientific community. In order to increase the success rates and efficiency of translocation projects it is necessary to highlight the reasons for project successes as well as project failures. This study aims to explore the relationship between two of the most commonly cited reasons for translocation failure, stress and illness, in a troop of translocated vervet monkeys (Chlorocebus pygerythrus) in Malawi. To do this, level of stress was determined through behavioral observations while binomial infection status and infection densities of parasitic helminth groups was determined through collection of fecal samples and a variety of diagnostic techniques. These translocated individuals showed higher helminth eggs per gram (EPG) than their wild counterparts. Individuals that displayed more stress related behavior had a higher chance of being positive for helminth infection, strongly suggesting that immunological impact of chronic stress incurred from being held in captivity. Juveniles tended to be more stressed than adults even though they tended to have lower EPG’s. This discrepancy may be explained by the fact that juveniles alter social interaction with infected individuals, possibly to reduce the chances of being infected themselves. These results show that there is a significant relationship between stress and helminth infection. This conclusion has wide-ranging management implication both in the translocation field as well as more general wildlife management. M-ECOL

Termites play a key-role in the savanna ecosystem. As primary producers and decomposers, they transport soil nutrients vertically and horizontally, creating a more heterogeneous landscape. Increased canopy cover will shade termite mounds and potentially disrupt the fine-tuned thermo-regulated central parts of the termite nests. In this study, I assessed the effect of woody encroachment in Lake Mburo National Park, Uganda on Macrotermes subhyalinus (Rambur) termites. I tested if mound activity and density, and if woody vegetation on termite mounds differed between the vegetation communities; natural, woody encroached and cleared (previously woody) savanna. Data was collected from 105 randomly located mounds (sites) in 15 areas. On each mound tree species, tree height, basal diameter (0.3 m), and diameter at breast height (1.3 m) was recorded. In addition to the random mounds, the five closest surrounding mounds were also checked for activity, giving a total of 612 surveyed mounds. All the mounds within a 40 m radius were counted for density measures, 967 mounds was recorded at the 105 sites. In total, I recorded 47 species comprising 1721 individual trees. Woody encroached and cleared areas had significantly lower proportions of active mounds than natural savanna areas, although, regardless of vegetation community, the abundance of M. subhyalinus was extremely low, with only 26 active mounds. The density of mounds (ha-1) was higher in the woody encroached areas (22.52 ± 6.6 SD) than in natural savanna (14.95 ± 7.37 SD) and cleared areas (16.47 ± 6.37 SD). The richness of woody vegetation on mounds was significantly higher in the natural savanna (9.4 ± 4.01 SD), than in woody encroached (6.8 ± 3.98 SD) and cleared areas (5.4 ± 2.96 SD). The evenness and diversity of woody vegetation on mounds was highest in natural savanna areas, but not significantly higher than in woody encroached and cleared areas. Mounds in cleared areas had more trees lower than 1.3 m in height than both mounds in woody encroached and natural savanna areas, while mounds in woody encroached areas had higher abundance of trees above 1.3 m in height, than mounds in cleared and natural savanna areas. Woody encroached and cleared areas had species abundance curves levelling around 30 species, while natural savanna areas had a species accumulation curve that did not level. Due to the overall low abundance of active mounds, regardless of woody vegetation cover, I concluded that other factors might cause the substantial overall decline of active termite mounds in Lake Mburo National Park. Termitter har en nøkkelrolle i et savanne-økosystem, der de er primærprodusenter og nedbrytere. De transporterer næringen i jorden og lager dermed et mer heterogent landskap. Fortetting av vegetasjonen vil gi økt skygge på termittuene og potensielt forstyrre de sensitive thermo-regulerte delene inne i tuene. Denne oppgaven ser på hvilke effekter fortetting av vegetasjonen i Lake Mburo National Park i Uganda har på andel av aktive tuer, og tettheten av tuer fra arten Macrotermes subhyalinus (Rambur). Jeg testet om aktiviteten, tettheten og tredekke på termitt-tuer var forskjellige i tre forskjellige vegetasjonstyper; naturlig savanne, gjengrodd savanne og ryddet (tidligere gjengrodd) savanne. I alt ble det samlet inn data fra 105 tilfeldig valgte tuer (sites), i 15 områder. På hver tue ble hvilken art, høyden på treet, bakkediameter (0.3 m) og diameter i bryst høyde (1.3 m) registrert. I tillegg til den tilfeldige tuen, ble de fem nærmeste tuene også sjekket for aktivitet. Totalt ble 612 tuer sjekket. Alle tuer innenfor en 40 m radius rundt den tilfeldige tuen ble telt for å se tettheten av tuer. 967 tuer ble telt i de 105 sitene. Totalt ble 1721 trær registret, fordelt på 47 arter. Gjengrodd og ryddet savanne hadde signifikant lavere andel aktive tuer enn naturlig savanne områder. Likevel var den totale andelen aktive M. subhyalinus tuer, uavhengig av vegetasjonstypen, ekstremt lav, med kun 26 registrerte aktive tuer. Tettheten av tuer per ha-1 var høyere i gjengrodd savanne (22.52 ± 6.6 SD) enn i naturlig (14.95 ± 7.37 SD) og ryddet savanne (16.47 ± 6.37 SD). Variasjonen av trær var signifikant høyere på den naturlige savannen (9.4 ± 4.01 SD), enn i gjengrodd (6.8 ± 3.98 SD) og ryddet savanne (5.4 ± 2.96 SD). Jevnheten og diversiteten av trær var høyest på den naturlige savannen, men ikke signifikant høyere enn i gjengrodd og ryddet savanne. Flere trær lavere enn 1.3 m ble funnet på tuer i ryddet savanne enn på tuer i både naturlig og gjengrodd savanne, mens tuer i gjengrodd savanne hadde høyere forekomst av trær over 1.3 m enn tuer i naturlig og ryddet savanne. Antall arter funnet i alle vegetasjonstypene var rundt 30, men en artsrikhets-kurve viste at antall arter observert på den naturlige savannen fortsatt var stigende. På grunn av den lave andelen av aktive termitt-tuer, uavhengig av vegetasjonstype, konkluderte jeg med at andre faktorer i tillegg til økt vegetasjonsdekke er grunnen til nedgangen i aktive termitt-tuer i Lake Mburo National Park. M-ECOL

Forest communities are complex because many factors are associated with the spatial patterns of woody species. The main objective of this thesis is to provide a better understanding of how woody species composition and diversity, as well as its components, are related and respond to environmental variables within a forest landscape. The environmental variables are both natural environmental factors and human-induced changes to a local environment. To capture a whole forest community assemblage and to understand how woody species respond to the environment through their life span, seedling, sapling and adult stages are thus considered. The thesis consists of four papers. The studies were conducted in a bamboo-deciduous forest, in northeastern Thailand. Three of the papers are observational studies and one is an experimental study. The first observational study attempts to find the most important determinants of woody species richness and diversity at different life stages. The second study examines if productivity and human disturbance can function as determinants of evenness in the relative abundance of growth stages (seedlings, saplings and adults) of woody species. The third study is concerned with niches of woody species, examining if their niches shift across the life stages. The experimental study was set up to determine effects of bamboos, which have become dominant in the forest, on woody seedlings regeneration. Overall, the results show that environmental variables rather than human disturbance were important in explaining the variation in woody species richness and diversity (Paper I). Productivity and human disturbance significantly explained the variation in evenness of adults and saplings, respectively, in which evenness decreased with productivity and human disturbance (Paper II). The soil phosphorus content was found to be the most important variable for seedlings as it had a negative relationship to their richness, evenness and diversity (Paper I and II). The sapling stage is the most susceptible to human disturbance which influences sapling richness, evenness and diversity (Paper I and II). Adult richness and diversity can be predicted by forest structure (i.e. number of bamboo clumps and canopy cover) (Paper I). The basal area (i.e. productivity) was the most important determinant for adult evenness (Paper II). When examining the environmental or niche requirements among the growth stages within a species, the nine most abundant species in the forest showed changes in their niche requirements across the growth stages (Paper III). The results from the experiment clearly showed that bamboos suppress regeneration of woody seedlings through their deep shade and litter on the forest floor. Seedling abundance and species richness were reduced by bamboo canopies, and removal of bamboo litter increased seedling abundance and species diversity (Paper IV). Although current human activities do not appear to have severe negative effect on community properties, a long term study and experiments are needed to clarify the effects of human disturbance on this forest community. A good management strategy for woody species should consider the situation for each life stage, since the environmental requirements of a species change across the ontogenetic stages. Finally, bamboos should be incorporated in management strategies when the aim is to maintain woody species richness and diversity in these forest ecosystems.