Deforestation and Recovery of the Tropical Montane forests of East Africa

Tropical montane forests are fragile ecosystems that provide a wide range of ecosystem services such as hydrological services, protection of biodiversity, and a contribution to climate change mitigation, yet they face degradation as well as losses due to deforestation. Deforestation poses a major threat yet whether these tropical montane forests recover from these changes is not well understood, especially for African montane forests. This study assessed rates of deforestation, and recovery using remote sensing of two important tropical montane forests of East Africa: the Mau Forest complex and the Mount Elgon forest. An in-depth study of aboveground biomass, species diversity and richness, and soil carbon and nitrogen stocks were conducted for the Mau forest complex. To conduct the detailed study, 47 forest plots were established to collect data subsequently used to calculate the rate of recovery of the aboveground biomass (AGB) and species recovery in 3 blocks of the Mau forest complex. From the same plots, soil samples were collected to assess the response of soil carbon (C) and nitrogen (N) stocks to 60 cm of soil depth from the different recovery stages. This study found that 21.9% (88,493 ha) of the 404,660 ha of the Mau forest Complex was lost at an annual rate of -0.82% yr-1 over the period between 1986-2017. However, 18.6% (75,438 ha) of the forest cover that was cleared during the same period and is currently undergoing recovery. In the Mt Elgon forest, 12.5% (27,201 ha) of 217,268 ha of the forest cover was lost to deforestation at an annual rate of -1.03 % yr-1 for the period between 1984 - 2017 and 27.2% (59,047 ha) of the forest cover that was lost is undergoing recovery. The analysis further revealed that for the Mau forest complex, agriculture (both smallholder and commercial) was the main driver of forest cover loss accounting for 81.5% (70,612 ha) of the deforestation, of which 13.2% was due to large scale and 68.3% was related to the smallholder farming. For the Mt Elgon forest, agriculture was also the main driver of forest loss accounting for 63.2% (24,077 ha) of deforestation followed by the expansion of human settlements that contributed to 14.7% (5,597 ha) of forest loss. For the aboveground biomass (AGB), it was found that AGB recovered rapidly in the first 20 years at an annual rate of 6.42 Mg ha-1, but the rate of recovery slowed to 4.67 Mg ha-1 at 25 years and 4.46 Mg ha-1, at 30 years of age. At 25 years, the mean AGB (198.32 ± 78.11 Mg ha-1) was statistically indistinguishable from the mean AGB in the old growth secondary forest (282.86 ± 71.64 Mg ha-1). Stem density, species diversity, and richness (i.e., Evenness index, Shannon’s index, and Simpson’s index) did not show any significant changes with the recovery stages of the secondary forest, although there existed a significant variation between the young secondary forests of age below 15 years from the old growth secondary forests. The study further found that, unlike the AGB and aboveground carbon (AGC), the soil C and N stocks were not significantly different across the recovery periods with mean soil C in the youngest forest 184.1 ± 41.0 Mg C ha-1 and old growth secondary forest as 217.9 ± 51.8 Mg C ha-1, the N stocks in the youngest forest was 16.4 ± 4.8 Mg N ha-1 and 20.1 ± 3.9 Mg N ha-1 for the old growth secondary forest. The findings of the study indicate that these tropical montane forests of East Africa are under threat resulting from forest clearance and deforestation. The forest AGB recovers after 25 years while the tree species richness and diversity, soil C and N stocks do not change significantly with the recovery stages. The effects of disturbances i.e., forest fire, charcoal burning, grazing (livestock), elephant damage, and fuelwood collection on the soil C and N stocks within the different recovery stages were not significantly different between old growth secondary forests and the other recovery stages. These findings contribute to the knowledge on the response of the tropical montane forest of East African to pressures of forest clearance and deforestation

The current state of Eastern Africa's forests

This report on the State of Forests and REDD+ Activities outlines, describes and provides analysis of the status of forests and REDD+ implementation in the east Africa region. It synthesizes and presents forest status information in a way that is easily understood by policy makers and practitioners involved in forest decision making and REDD+.JRC.D.1-Bio-econom

Land Degradation Assessment with Earth Observation

This Special Issue (SI) on “Land Degradation Assessment with Earth Observation” comprises 17 original research papers with a focus on land degradation in arid, semiarid and dry-subhumid areas (i.e., desertification) in addition to temperate rangelands, grasslands, woodlands and the humid tropics. The studies cover different spatial, spectral and temporal scales and employ a wealth of different optical and radar sensors. Some studies incorporate time-series analysis techniques that assess the general trend of vegetation or the timing and duration of the reduction in biological productivity caused by land degradation. As anticipated from the latest trend in Earth Observation (EO) literature, some studies utilize the cloud-computing infrastructure of Google Earth Engine to cope with the unprecedented volume of data involved in current methodological approaches. This SI clearly demonstrates the ever-increasing relevance of EO technologies when it comes to assessing and monitoring land degradation. With the recently published IPCC Reports informing us of the severe impacts and risks to terrestrial and freshwater ecosystems and the ecosystem services they provide, the EO scientific community has a clear obligation to increase its efforts to address any remaining gaps—some of which have been identified in this SI—and produce highly accurate and relevant land-degradation assessment and monitoring tools

Physiological and ecological effects of fencing elephants in montane forests, Kenya

Worldwide, wildlife populations are declining at an unprecedented rate, anthropogenic influences including habitat-loss, poaching, and over-exploitation are driving many species to extinction. A rapidly increasing human population and subsequent conversion of land use, has intensified a competition of resources between humans and wildlife. Human elephant conflict (HEC) is a prominent concern and whilst many attempts have been made to mitigate conflict, many are unsuccessful, as such, Kenya embarked on the necessary strategy of fencing its montane forests to separate elephants from people. Whilst fencing successfully reduced conflict, the physiological and ecological effects of confining elephants in forests is unknown. This thesis is the first study examining the impact of fencing elephants in montane forests, on both the ecological impact on the integrity of the forest habitat, and the impact of isolation on the demographic structure, and physiology of the elephant population. The outcomes of this study will be used to inform the future management of elephant populations in forest habitats throughout their range. Chapters of this thesis address the following outcomes; (1) the impact of confining African elephants (Loxodanta africana) on the extent and quality of a forest habitat and (2) to provide a density estimate of elephants in a montane forest by employing the Random Encounter Model (REM) with camera traps. Additionally (3), it also assesses the impact of restricting dispersal on the demographic structure of elephant populations compared to free-roaming populations, and (4) examines the physiological effect of confinement on elephants. To provide an assessment of the impact of confinement on the forest habitat, changes in the forest canopy were mapped by applying the Breaks For Additive Season and Trend (BFAST) model using a time-series of MODIS satellite data on the 2 fenced forest habitats of varying sizes. Change maps produced from the BFAST model on MODIS timeseries data revealed that 13% of the Aberdare National Park had undergone a change in vegetation, with 0.9% loss to the forest. Similarly, the Shimba Hills National Reserve underwent significant change over the 12-year period, averaging a 9% change in the area per year with both positive ‘greening’ events and forest degradation. Density estimates calculated from the REM yielded results averaging 0.49 elephants/ km2 which falls in line with expected estimates in protected areas. Demographic results determined that the age viii class frequencies for the Aberdare Conservation Area (ACA) were significantly different to parity (x 2 = 147.24, df = 2, p-value < 0.001), showing a skewed age distribution towards adults and sub-adults and a lower proportion of juveniles. Comparison of the age class frequencies in the ACA to 3 populations from published data of known status (stable, and rapidly increasing) revealed that the ACA population were significantly different to both stable populations (x 2 = 495.05, p-value < 0.001; x 2 = 215.98, p-value < 0.001), and the rapidly increasing population (x 2 = 329.1, p-value < 0.001). The number of dependents to adult females was significantly lower compared to the control populations (x2 = 9.0872, df = 3, p-value = 0.02815). Endocrine analysis of adrenal activity found significant differences in FGM concentrations between the confined ACA population, a free-roaming savannah population, and a population from a montane forest that utilises a wildlife corridor to the lowland savannah (R2 =0.2331, F = 35.1, df= (2), 231, p-value < 0.001). At 3.73 ng/g (95%CI, 3.35-4.16), the confined ACA population is 91% higher than the Lewa Wildlife Conservancy (LWC) population with a wildlife corridor (1.95 ng/g, 95% CI, 1.72-2.21) and 68% higher than the Samburu National Reserve (SNR) population (2.22 ng/g, 95% CI, 1.98-2.59). No significant differences in FGMs were observed between the two free-roaming (LWC and SNR) populations. The greatest difference in FGM concentrations were observed in the subadult age class, with the ACA averaging 4.13 ng/gm (95% CI, 3.58-4.76) compared to 1.87 ng/g (95% CI, 1.59-2.1) in the LWC, and 2.74 ng/g, (95% CI, 2.28-3.30) in the SNR. Whilst the ACA exhibited only small-scale degradation, and the current density of elephants falls within the expected densities for protected areas. Significant differences were observed in the demographic structure and physiological condition of the isolated elephant population. The age-distribution was skewed towards the adult age classes, and concentrations of adrenal hormones were elevated. As such, these could have negative implications on population growth rates, and the subsequent viability of the population

Elephant space use in relation to ephemeral surface water availability in the eastern Okavango Panhandle, Botswana

The movement and distribution of elephants can be influenced by environmental factors over time (Foley, 2002). Examining how features in the landscape such as vegetation productivity, water sources and anthropogenic activities drive the movement of elephants can help in understanding patterns of movement. It can also help to inform the establishment and alignment of protected areas, wildlife corridors and identification of tourism hotspots as well as policy interventions to manage Human-Elephant Conflict (HEC). The Okavango Panhandle in Botswana is a HEC hotspot and the focus of My study. A number of strategies to address HEC are underway in the area, however one longer term strategy that has been proposed in this area involves provision of artificial water sources to influence elephant movements and keep animals away from fields during the cropping season. However, an improved understanding of how elephants utilize their habitats in relation to natural ephemeral surface water and other factors that influence their movements from dryland habitats to the Okavango Delta resources is needed to inform such management decisions. My study seeks to establish the role of ephemeral surface water on elephant distribution in the eastern Okavango Panhandle, Botswana as well as assess the movement distribution of elephants in relation to the seasonality, proximity and spatial extent of water presence represented by ephemeral surface water. Time series analysis of water extent on ephemeral surface water of the eastern Okavango panhandle will be developed and overlaid with elephant movement datasets. Elephant collar data from 15 elephants (5 males and 10 females) in the eastern Okavango Panhandle, Botswana have been analysed and Home Range (HR) sizes estimated using Kernel Density Estimation (KDE). The relative importance/probability of environmental variables in determining elephants' movement based on the Utilization Distribution (UD) were computed using Generalized Linear Mixed Models (GLMMs). I utilized a remote sensing spectral index, namely the Automated Water Extraction Index (AWEI) to delineate ephemeral surface water in dryland (excluding permanent waters) of the study area. The results reveal that during the wet season, elephants were evenly spread out all over the study area until the early dry season (April-June) when the ephemeral waterholes dried up. Elephants moved southwards towards the permanent waters of the Okavango River, where there are many human settlements and farms. Male HR sizes were found to be bigger than those of female elephants. Wet season (early and late) home range sizes were also bigger when compared to dry season (early and late) HR size. Mean daily distances were computed to investigate the effect of season on elephant daily distances and the distances ranged between 5km and 6.8km in the late wet and in the early wet and late dry season respectively. The Resource Selection Function (RSF) analysis shows that water adjacent sites are preferred over distant ones and both sexes prefer areas with high NDVI, with this preference being more pronounced in males. The seasonal variation of water use is notable in that it affirms the importance of proximity to water for elephants and has implications for their management and HEC. For example, I found that ephemeral surface water has a significant role in influencing elephant spatial use in the area, particularly during the early and late wet season. As ephemeral pans dried and NDVI (vegetation greenness) decreased, elephants started to move closer to the Okavango Delta and consequently human settlements and fields. However, further investigations into the timing of movements away from ephemeral waterholes and the influence of other environmental factors on elephant movements in the area would be needed before any recommendations can be made regarding artificial water provision in this area

A characterization of landslide occurrence in the Kigezi Highlands of South Western Uganda

The frequency and magnitude of landslide occurrence in the Kigezi highlands of South Western Uganda has increased, but the key underpinnings of the occurrences are yet to be understood. The overall aim of this study was to characterize the parameters underpinning landslide occurrence in the Kigezi highlands. This information is important for predicting or identifying actual and potential landslide sites. This should inform policy, particularly in terms of developing early warning systems to landslide hazards in these highlands. The present study analysed the area’s topography, soil properties as well as land use and cover changes underpinning the spatialtemporal distribution of landslide occurrence in the region. The present study focussed on selected topographic parameters including slope gradient, profile curvature, Topographic Wetness Index (TWI), Stream Power Index (SPI), and Topographic Position Index (TPI). These factors were parameterized in the field and GIS environment using a 10 m Digital Elevation Model. Sixty five landslide features were surveyed and mapped. Soil properties were characterised in relation to slope position. Onsite soil property analysis was conducted within the landslide scars, auger holes and full profile representative sites. Furthermore, soil infiltration and strength tests, as well as clay mineralogy analyses were also conducted. An analysis of the spatial-temporal land use and cover changes was undertaken using satellite imagery spanning the period between 1985 and 2015. Landslides were noted to concentrate along topographic hollows in the landscape. The occurrence is dominant where slope gradient is between 25˚ and 35˚, profile curvature between 0.1 and 5, TWI between 8 and 18, SPI >10 and TPI between -1 and 1. Landslides are less pronounced on slope zones where slope gradient is 45˚, profile curvature 18, SPI 1. Deep soil profiles ranging between 2.5 and 7 meters are a major characteristic of the study area. Soils are characterized by clay pans at a depth ranging between 0.75 and 3 meters within the profiles. The study area is dominated by clay texture, except for the uppermost surface horizons, which are loamy sand. All surface horizons analysed had the percentage of sand, silt and clay ranging from 33 to 55%, 22 to 40% and 10 to 30% respectively. In the deeper horizons, sand was observed to reduce drastically to less than 23%, while clay increased to greater than 50%. The clay content is very high in the deeper horizons exceeding 35%. By implication, such soils with a very high clay content and plasticity index are considered as Vertisols, with a profound influence in the occurrence of landslides. The top soil predominantly contains more quartz, while subsurface horizons have considerable amounts of illite/muscovite as the dominant clay minerals, ranging from 43% to 47 %. The liquid limit, plasticity index, computed weighted plasticity index (PIw), expansiveness (ɛex) and dispersion ranging from 50, 22, 17, 10 and 23 to 66, 44,34,54 and 64, respectively also have strong implications for landslide occurrence. Landslides are not normally experienced during or immediately after extreme rainfall events but occur later in the rainfall season. By implication, this time lag in landslide occurrence and rainfall distribution, is due to the initial infiltration through quartz dominated upper soil layers, before illite/muscovite clays in the lower soil horizons get saturated. Whereas forest cover reduced from 40 % in 1985 to 8% in 2015, cultivated land and settlements increased from 16% and 11% to 52% and 25% respectively during the same period. The distribution of cultivated land decreased in lower slope sections within gradient group < 15˚ by 59%. It however increased in upper sections within gradient cluster 25˚ to 35˚ by over 85% during the study period. There is a shift of cultivated land to the steeper sensitive upper slope elements associated with landslides in the study area. More than 50% of the landslides are occurring on cultivated land, 20% on settlements while less than 15 % and 10% are occurring on grassland and forests with degraded areas respectively. Landslides in Kigezi highlands are triggered by a complex interaction of multiple- factors, including dynamic triggers and ground condition variables. Topographic hollows are convergence zones within the landscape where all the parameters interact to cause landslides. Topographic hollows are therefore potential and actual landslide sites in the study area. Characterized by deep soil horizons with high clay content dominated by illite/muscovite minerals in the sub soils and profile concave forms with moderately steep slopes, topographic hollows are the most vulnerable slope elements to landslide occurrence. The spatial temporal patterns of landslide occurrence in the study area has changed due to increased cultivation of steep middle and upper slopes. Characterized by deep soil horizons with high clay content dominated by illite/muscovite minerals in the sub soils and profile concave forms with moderately steep slopes, topographic hollows are the most vulnerable slope elements to landslide occurrence. The spatial-temporal patterns of landslide occurrence in the study area has changed due to increased cultivation of steep middle and upper slopes. A close spatial and temporal correlation between land use/cover changes and landslide occurrence is discernible. The understanding of these topographical, pedological and land use/cover parameters and their influence on landslide occurrence is important in land management. It is now possible to identify and predict actual and potential landslide zones, and also demarcate safer zones for community activities. The information generated about the area’s topographic, pedological and land cover characteristics should help in vulnerability mitigation and enhance community resilience to landslide hazards in this fragile highland ecosystem. This can be done through designating zones for community activities while avoiding potential landslide zones. It is also recommended that, tree cover restoration be done in the highlands and the farmers encouraged to re-establish terrace farming while avoiding cultivation of sensitive steep middle and upper slope sections

Analysing and Applying Stakeholder Perceptions to Improve Protected Area Governance in Ugandan Conservation Landscapes

Given the diversity of active institutions and stakeholders in a landscape, and the difficulties in ensuring inclusive decision-making, evaluating landscape governance can help surface and address underlying issues. In the context of two protected area landscapes in Uganda, where landscape approaches are being implemented through a wider project on landscape governance, we analyse stakeholder perceptions of inclusive decision-making and then use this evaluation to stimulate dialogue amongst stakeholder groups in each landscape. We ask, how can capturing, analysing, and collaboratively applying people&rsquo;s perceptions address inclusive decision-making in landscape governance? We collected and analysed perceptions using SenseMaker&reg;, a software package that enables analysis of micronarratives (stories) from the field based on how respondents classify their own stories, using triads, dyads, stones, and multiple-choice questions. This self-categorisation by the respondent reduces bias in the analysis and allows the micronarrative to be cross-examined in a variety of ways when analysed using Sensemaker. This analysis created an integrated view of the stakeholder&rsquo;s perceptions about inclusive decision-making in landscape governance. The results show large portions of the respondents feel their voices are neglected, and management of the landscape is poor in Mount Elgon, while in Agoro-Agu, it is the opposite trend. During a community feedback process, reasons for these trends were discussed and solutions proposed. Some of the underlying factors include historical relationships with park authorities and displacement during park creation. To more precisely answer our research question, one could have extended stays in the communities studied in these landscapes, using ethnographic methods including interviews and participant observation; nonetheless, our method, including the feedback process, was an innovative and important way to confront our findings with the informants directly and foster collaborative action. We conclude that understanding people&rsquo;s perceptions, including through participatory feedback, can significantly inform and improve management decisions, help resolve conflicts, and facilitate dialogue between different stakeholders in the landscape

Strengthening the Resiliency of Dryland Forest-Based Livelihoods in Ethiopia and South Sudan: A Review of Literature on the Interaction Between Dryland Forests, Livelihoods and Forest Governance

Dry forests account for nearly half of the world’s tropical and subtropical forests and provide a multitude of ecological services. They contribute to hydrological cycles and livestock and wildlife provisioning; and host pollinators and wild plants. They are also important ecological zones for dryland agriculture and pastoral livelihood strategies that support hundreds of millions of people around the world. Dry forests cover large areas and their biomass stores carbon and helps mitigate climate change. Dry forests are particularly important to people in Africa. They provide wood for construction and energy, contribute to local diets with wild fruits, vegetables, nuts, edible insects and bushmeat. Wild, edible plants provide essential nutrients, particularly during times of food scarcity. Yet dry forests are subject to high rates of deforestation and degradation driven mainly by agricultural expansion and growing energy demands. Other challenges include limited information on dry forests (their inventories, changes over time, major drivers of deforestation and recovery, etc.), their biophysical aspects and ecosystem services and the potential roles they could play in increasing the sustainability of crop and livestock farming. Governments, development partners and communities are looking for options to better manage these resources at the landscape level. Dry forests are complex ecosystems that are not fully understood. Scientific knowledge to better manage dry forests and sustain the livelihoods of people that depend on these ecosystems remains scanty as research to inform policy and practice is still very limited. The knowledge gap is even more pronounced in northeastern Africa, notably Ethiopia and South Sudan where these forest types are important in terms of areas coverage and in supporting rural livelihoods. Ethiopia and South Sudan share histories of political unrest and conflict that have contributed to famines; large-scale land acquisition for investment and agricultural expansion by smallholders are resulting in major and rapid land-use changes in their dry forested areas. Ethiopia’s two decades of peace and stability and its experience in managing its natural resources could inform post-conflict intervention measures in South Sudan. This study was conducted as an effort to help fill the knowledge gap in dry forest-based livelihoods through a critical review of the available literature. It used publications from CIFOR’s work on dry forests and product marketing in Ethiopia and from other sources, including gray literature. The study assessed the socio-ecological context, including relevant laws and strategies, with an emphasis on the biophysical characteristics of the dryland forests of Ethiopia and South Sudan and the major causes of deforestation and forest degradation. Using livelihood systems as an analytical framework, it examined (i) major livelihood strategies; (ii) the contribution of dry forests to livelihoods; (iii) forest product markets and value chains; and (iv) forest and land governance with an emphasis on the relationship between political, economic and resource management policies and the level of degradation of dry forests and their contributions to the livelihoods of forest-dependent communities in Ethiopia and South Sudan. It also identified major threats to dry, forest-based livelihoods and key issues for policy, research and practice that need to be addressed to maintain the multifunctionality of dryland forests while also ensuring the well-being of communities dependent on these landscapes

INTEGRATED MODELING OF LAND USE AND CLIMATE CHANGE IMPACTS ON MULTISCALE ECOSYSTEMS OF CENTRAL AFRICAN WATERSHEDS

Assessment and management of ecosystem services demands diverse knowledge of the system components. Land use change occurring mainly through deforestation, expansion of agriculture and unregulated extraction of natural resources are the greatest challenges of the Congo basin and yet is central to supporting over 100 million people. This study undertook to implement an integrated modeling of multiscale ecosystems of central African watersheds and model the impact of anthropogenic factors on elephant population in Greater Virunga landscape. The study was conducted at varied scales, regional, landscape, and community. Regional study included watershed analysis and hydrological assessment using remotely sensed data implemented in Geographical information System. Species distribution modeling using generalized linear models using presence only and pseudo absence data was also done at regional scale. The major findings were that ecosystem services for the Congo basin are spatially varied and there are significant differences in their distribution of ecosystem services at a subwatershed level three and six and the distribution of endangered and threatened species is more concentrated in the central part of the basin and most of these species occur mainly inside protected areas. Poaching and sustained civil wars were the biggest threat to elephant conservation in the region. Improvement in law enforcement, monitoring, and increasing household incomes for communities living adjacent to protected areas would help to reduce the impact of poaching on elephant population dynamics. Climate change did not show immediate direct impacts on the elephant population, but thermal and latent heat effects could be occurring. A change in habitat, however, showed resulted in an upward trend in elephant population for all age classes. The local communities heavily depend on these ecosystem services for their livelihoods. It is therefore recommended that reasonable financing to strengthen law enforcement and monitoring is done, multiple policy options should be considered in order to maximize ecosystem benefits. Creation of partnerships and research networks need to be promoted. Existing transboundary collaboration initiatives should continue and be supported by the donor community in order to build peace and dram support for wildlife and wild habitat protection