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<p>Traditional forest reserves are protected natural forests established by ancestors to perform many socio-cultural functions and are protected in accordance to customary laws, not based on government legislation. These reserves generally have a long history with well preserved forests that could demonstrate what the surrounding environment could have looked liked, if humans had not altered it. Therefore, the traditional forest reserves might have significant ecological value and a potential high biodiversity. During February and March of 2009 a field study with semi-structured interviews and field observations was carried out in Babati District in Manyara Region in Tanzania, to study the possible contribution TFRs might have to conservation. The information collected were then analysed using Metapopulation Theory, Island Biogeography Theory and local knowledge concepts. The analysis indicates that there is a higher biodiversity in TFRs compared to surrounding areas and unprotected forests as a result of a rigid traditional protection that local people respect. Further on the MPT and IBT show how TFRs could benefit conservation as islands of refuge for threatened species or as migration corridors between nearby forest reserves and national parks. The future for TFRs and possible conversion into CBFM must include respect and support for the local beliefs as a basis for protection and thereby conservation.</p>

Traditional forest reserves are protected natural forests established by ancestors to perform many socio-cultural functions and are protected in accordance to customary laws, not based on government legislation. These reserves generally have a long history with well preserved forests that could demonstrate what the surrounding environment could have looked liked, if humans had not altered it. Therefore, the traditional forest reserves might have significant ecological value and a potential high biodiversity. During February and March of 2009 a field study with semi-structured interviews and field observations was carried out in Babati District in Manyara Region in Tanzania, to study the possible contribution TFRs might have to conservation. The information collected were then analysed using Metapopulation Theory, Island Biogeography Theory and local knowledge concepts. The analysis indicates that there is a higher biodiversity in TFRs compared to surrounding areas and unprotected forests as a result of a rigid traditional protection that local people respect. Further on the MPT and IBT show how TFRs could benefit conservation as islands of refuge for threatened species or as migration corridors between nearby forest reserves and national parks. The future for TFRs and possible conversion into CBFM must include respect and support for the local beliefs as a basis for protection and thereby conservation.

The islands of the tropical South Pacific (TSP) are considered biodiversity hotspots. However, the biota of this region has received limited scientific attention and very little is known about its diversity, ecology and evolution. In this thesis we investigate some of the ecological and evolutionary processes in the TSP, focussing on lowland rain forests. We use molecular techniques to investigate evolutionary processes and vegetation surveys to study species diversity patterns and ecological processes. Chapter 1 reviews molecular, distributional and geographic evidence for dispersal versus vicariance explanations for the diversity and distribution of the TSP biota. Most islands of the TSP are geologically young (less than 40 million years old) and of oceanic origin, so most (if not all) of the biota on islands in the TSP arrived through long-distance dispersal events. This view is strongly corroborated by genetic data from published studies. Molecular studies also suggest two major source areas. One is located in the northwest, which includes Malesia and Southeast Asia, while the other is in the southwest and includes New Caledonia, Australia and New Zealand. We argue that local extinctions have occurred in source and stepping stone areas, creating sources of error for the interpretation of distribution and molecular data. In Chapter 2 we use allozyme data to investigate the question how Pacific cycads (Cycas, subsection Rumphiae) colonised the Pacific. We show that they colonised the Pacific and East Africa by long-distance dispersal, probably through floating seeds from a Malesian source area. Allozymes and morphological data provide support for two major groups within subsection Rumphiae and reveal close relationships between the extant species, suggesting very recent and/or ongoing dispersal events. Cycads are an example of recent diversification in a lineage with a long fossil record. The podocarp genus Dacrydium is another lineage with a long fossil record and in chapter 3 we investigate the colonisation and speciation processes in this lineage using allozymes and trnL-trnF plastid sequences. Our results suggest that the Pacific species of Dacrydium arrived recently (within the last 10 million years) in the TSP but are inconclusive about the source area of the genus. Combined molecular and ecological data suggest the occurrence of both allopatric and sympatric speciation in the Pacific radiation in this genus. Allozyme data also demonstrate the occurrence of hybridisation between two New Caledonian species. Our findings suggest that hybridisation and sympatric speciation may have played an important role in the evolution of the biota in the TSP. In chapter 4 we attempt to untangle the disparate forces driving alpha species diversity, forest structure and species composition in old-growth lowland tropical rainforest by assessing the tree species composition of twelve 1 ha vegetation count plots on 13 islands between New Guinea and Samoa. Using simplifications of a model based on biogeographic and ecological disturbance theory, we show that species diversity and richness are mainly influenced by size and area of an island, while endemism is mostly determined by isolation and area. High cyclone frequency is shown to increase the density of stems (with dbh > 10 cm). Correlations between the abundance of widespread canopy tree taxa and cyclone frequency suggest that cyclones affect species composition by increasing the abundance of cyclone-resistant species. However, floristic similarities show that geographic distance also affects species composition. It therefore appears that, for lowland rain forests in the TSP, biogeography is the major driver of species diversity and endemism and that disturbance is the major driver of forest structure, while both biogeography and disturbance affect the species composition. In chapter 5 we test the ability of NDVI (Normalised Difference Vegetation Index, a remotely sensed index of productivity) data and leaf samples as covariates of alpha species diversity using twelve vegetation count plots. NDVI performed poorly in estimating species diversity and species richness. However, the cost- and time-efficiency associated with remotely sensed data shows the potential of these methods, but only if accurate methods to estimate species richness are found. Species richness and species diversity estimates obtained from leaf litter samples correlate reasonably well with similar estimates obtained from count plots and are more than 30% cheaper and about 10% faster to obtain. If travel can be avoided through collaboration, leaf litter-based estimates of diversity could be obtained at about 5% the cost and in about half the time compared to count plots. Therefore the analysis of leaf litter is potentially a suitable and efficient method to obtain rapid estimates of species diversity in count plots. The final chapter discusses the roles of ecological and evolutionary processes in the TSP. While research to date has been scarce, especially on ecological processes acting on large scales, data show that the effects of ecology, evolution and biogeography are interlinked during the colonisation, establishment and subsequent evolution of taxa and biomes in the TSP.

The marine ecosystem provides key resources to terrestrial organisms inhabiting oceanic islands. These subsidies of marine resources have the potential to affect species richness, ecology and productivity, especially on islands with high perimeter-area ratios. I investigated the impact and importance of marine subsidies on mammal diversity and diet on islands of British Columbia’s Central Coast. Insular mammal species richness was significantly correlated with island area and quantity of marine subsidy (wrack). However, mink and river otter island occupancy was unaffected by island-level covariates, whereas small mammals were more likely to occupancy islands closer together. Keen’s mice and food items were subsidized directly (i.e., consumption) and indirectly (i.e., fertilization) by marine resources. Beach-dwelling arthropods composed 33% of mouse diets. Furthermore, mouse and terrestrial arthropod abundances and stable isotope signatures (d13C and d15N) of food items were depleted moving inland from the beach. Finally, reproductive male mice consumed up to twice the marine-derived prey as females. Collectively, this work demonstrates that insular mammalian richness, as mediated by island-level factors, may be complex due to variation within populations and the recipient ecosystem (e.g., prey biomass). / Graduate

The equilibrium theory of island biogeography provides a useful model for understanding patterns of species richness on island systems and analogous fragmented terrestrial habitats. However, like all models, it is limited in its ability to explain island species richness patterns when nutrients move across ecosystem boundaries. Recently, enhancements to the theory have been proposed, including the subsidized island biogeography hypothesis. This hypothesis suggests that nutrient subsidies from the marine environment may impact the productivity and diversity of small islands. Sea wrack (dead, shore-cast seaweed) is a recognized vector of marine-nutrient subsidies to islands in regions of low in situ productivity, but little is known about the mechanisms surrounding sea wrack accumulation in productive, temperate environments. In this research I explore the spatial and temporal distribution of sea wrack on islands along British Columbia’s temperate Central Coast. Through an observational study I investigate three broad factors that could affect sea wrack deposition: climatic patterns, physical characteristics of shorelines, and the amount of nearby donor habitat. I surveyed sea wrack biomass and species composition, as well as the biogeographical characteristics of shorelines across 455 sites on 101 islands. I returned to a subset of sites on a bi-monthly basis to document temporal changes in wrack biomass and species composition. My results demonstrate that sea wrack accumulations were present at sites that were not composed of rock substrate, and that had wide, wave protected shorelines and high amounts of nearby donor ecosystem habitat. Additionally, sea wrack biomass and species composition was ubiquitous throughout all seasons. These results suggest that sea wrack can be considered a press subsidy as it is a consistent vector of nutrients to beaches along the Central Coast. Ecological research on macrophytes, macroalgae and sea wrack often requires the conversion of wet biomass to dry, to create consistency across investigations. This is a laborious process. Here, I present the results of wet-dry calibrations for 12 common macrophyte and macroalgae species collected from the Northeast Pacific Ocean. Future investigators can use the correction factors derived from these results for estimating dry biomass, reducing the need to conduct wet-dry calibrations for each new macrophyte, macroalgae, or sea wrack study. / Graduate

Using metacommunity theory, I investigated the mechanisms of meta-assemblage structure and assembly among medium- to large-bodied mammals in North Texas. Mammals were surveyed with camera-traps in thirty property units of the LBJ National Grasslands (LBJNG). In Chapter II the dispersal and environmental-control based processes in community assembly were quantified within a metacommunity context and the best-fit metacommunity structure identified. A hypothesis-driven modelling approach was used in Chapter III to determine if the patterns of species composition and site use could be explained by island biogeography theory (IBT) or the habitat amount hypothesis (HAH). Islands were defined as the LBJNG property unit or the forest patch bounded by the property unit. Forest cover was selected as the focal habitat for the HAH. Seasonal dynamics were explored in both chapters. Metacommunity structure changed with each season, resulting in quasi-nested and both quasi and idealized Gleasonian and Clementsian structures. Results indicated that the anthropogenic development is, overall, not disadvantageous for this assemblage, that community assembly receives equal contributions from spatial and environmental factors, and that the metacommunity appears to operate under the mass effects paradigm. The patterns of species composition and site use were not explained by either IBT or HAH. Likely because this assemblage of generalist, dispersal-capable mammals are utilizing multiple habitat types both in the protected land and in the private land. This research highlights the versatility of these species and the potential value of rural countryside landscapes for wildlife conservation.

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Epiphytic lichens are important species in the forest ecosystem. The Swedish forestry model affects them by fragmenting large old continuous forests. These fragments could be used as islands in a test of MacArthur and Wilsons theory of island biogeography. This study investigates if island biogeographic factors such as area and distance from nearest continuous forest affects lichen diversity in forest fragments, In addition time since logging to investigate if the populations will reach equilibrium and also if differences in habitats such as forest volume affects lichen diversity in addition to island biogeography. The number of lichen species were examined in 15 boreal forest fragments north of Storuman municipality, Västerbotten.   According to the results, positive significant correlations were observed between the number of lichen species and island biogeographic variables in the area of the islands. No positive correlations could be observed between the number of lichen species and distance to the nearest continuous forest.  There were also significant correlations between number of species and time since logging around the forest islands. However, there were positive correlations between the number of lichen species and forest volume, which tells us that more than island biogeographic factors that affect lichens in the form of habitat changes. This study indicates that in order to favor lichen diversity in forest landscapes it is important to maintain larger forest fragments with older trees. Clearly forest management agencies should consider the complex ecology of lichens when planning and performing forestry practices.

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