Impacts of mining on land use - A case (study) of Luanshya district, Zambia

Copper mining is the main driver of Zambia’s economic growth and development and plays a significant role in the global supply of materials for electrical, plumbing, heating and transport equipment among other benefits. However, primary production and beneficiation of copper pose serious risks to the mining districts such as environmental pollution, landscape alterations, land degradation and social economic challenges to the host communities. This research looks at the landscape alterations in the mining district of Luanshya, and how these alterations are related to mining and other land uses. Using remote sensing and Geographic Information Systems (GIS), the landscape alterations were mapped and analysed to identify the processes causing these alterations and their impacts on land use. Secondly, stakeholder interviews were conducted to gain a deeper understanding of the mapped landscape alterations, what the approach has been to land use planning and the stakeholder roles in this planning. Analysis of the findings identifies that landscape alterations in the district have been caused by different inter-related mechanisms stemming from a number of causes. These causes include high dependency on copper mining; inadequate enforcement of environmental legislation; lack of state involvement in land use planning of mining districts; and also global factors such as commodity market conditions. As a result, boom and bust commodity cycles have had significant impacts on the wellbeing of both mining communities and the environment. These impacts are not limited to the mine sites alone but extend to entire districts. This research also identifies that while mining plays a vital role in the economic development of Zambia, adequate enforcement of environmental legislation and adoption of inclusive land use planning may stimulate sustainable development of mining districts and foster sustainable land use patterns. Furthermore, this study recommends that future land use planning must be dynamic in terms of adopting postmining restoration of landscapes and infrastructure while also taking the direct and indirect impacts of mining into account

Deforestation by Afforestation: Land Use Change in the Coastal Range of Chile

In southern Chile, an establishment of a plantation-based forest industry occurred early in the industrial era. Forest companies claim that plantations were established on eroded lands. However, the plantation industry is under suspicion to have expanded its activities by clearing near-natural forests since the early 1970s. This paper uses a methodologically complex classification approach from own previously published research to elucidate land use dynamics in southern Chile. It uses spatial data (extended morphological profiles) in addition to spectral data from historical Landsat imagery, which are fusioned by kernel composition and then classified in a multiple classifier system (based on support, import and relevance vector machines). In a large study area (~67,000 km2), land use change is investigated in a narrow time frame (five-year steps from 1975 to 2010) in a two-way (prospective and retrospective) analysis. The results are discussed synoptically with other results on Chile. Two conclusions can be drawn for the coastal range. Near-natural forests have always been felled primarily in favor of the plantation industry. Vice versa, industrial plantations have always been primarily established on sites, that were formerly forest covered. This refutes the claim that Chilean plantations were established primarily to restore eroded lands; also known as badlands. The article further shows that Chile is not an isolated case of deforestation by afforestation, which has occurred in other countries alike. Based on the findings, it raises the question of the extent to which the Chilean example could be replicated in other countries through afforestation by market economy and climate change mitigation

Modelling land-use decision-making in encroached forests, Copperbelt Province, Zambia

Natural resource management is an important issue around the world in the light of increased global population size and the subsequent demands arising from an increased need for food, clean water and other ecosystem services. This has often resulted in the encroachment of protected areas and the adoption and maintenance of unsustainable land use practices. This study is concerned with the development of tools that will help us understand the characteristics of land use decision-making by people who illegally settle in protected areas. The study has the main aim of developing a model of local stakeholder land-use decision-making for the encroached forest areas in the Copperbelt Province of Zambia. This will allow the modelling of the stakeholder land-use practices. This will help predict their effects on the environment of the Province. Soft Systems Methodology (SSM) was used to develop a conceptual model of land use decision making in the study area and the outputs from SSM were used to develop a Belief Network (BN) model of land use decision making in the study area. Decision trees were also used to model the land use decision-making characteristics of the local stakeholders in the area. The findings suggest that SSM is a useful tool for the modelling of the complex problem situation in the study area and the subsequent development of solutions to the problems identified through participatory approaches. The research also showed that BNs and decision trees were able to model land use decision-making by using the agricultural activity as a basis for analysis. The findings suggest that BNs and decision trees are complementary and have the potential for addressing applications in land-use decision-making in informal settlements where available information is more likely to be scant and disparate

Understanding climatic-landscape-hydrological interactions at a Meso-scale to guide global change adaptation : a study in the Kaleya river catchment, Zambia

Thesis (PhD (Water Resource Management))--University of Pretoria, 2022.This study examined the climatic-landscape-hydrological interactions in a catchment facing landscape fragmentation, agricultural intensification, and increased climatic risks. The study took a holistic approach by examining past, present, and future interactions using the lenses of the green-blue water approach to devise interventions for improved water storage and management in the case study of the Kaleya River Catchment (about 750 km2) of southern Zambia. The results could be extrapolated to other semi-arid areas with similar hydro-geological and climatic settings. To assess the past interactions, a simple landscape hydrology approach was developed and applied to determine factors explaining seasonal water availability and provide insights on how landscape components could be enhanced to augment natural river flows and reduce sediment loss. Based on the Variable Importance in Projection (VIPs), results showed that seasonal climatic and weather extremes involving rainfall intensities, rainfall variability and dry spell length were more important than annual rainfall totals in explaining seasonal water availability. Additionally, patchiness of cover was more important in explaining seasonal water availability than the percentage of cover type in the landscape (PLAND). The Patch Density (PD) and Largest Patch Index (LPI) of reservoirs were the main landscape pattern stressors, alongside percentage of cover type metrics involving PLAND of irrigated cropland and reservoirs. But the LPI of forestland positively explained seasonal river flows. The study recommended that water resource interventions in the region must adapt more to changing seasonal rainfall characteristics than to annual rainfall totals. Additionally, regeneration of larger forest patches could improve river flows. To understand the climatic-landscape-hydrological interactions in the present, naturally occurring stable water isotopes [deuterium (δ 2H) and oxygen-18 (δ 18O)], hydro-chemical parameters [chloride (Cl-1) and electrical conductivity (EC)] were used as tracers. Based on the combination of end member mixing analysis and mixing model analysis, the major streamflow sources could be evaluated. The results revealed that stormwater runoff from non-irrigated areas (43 ± 13) %, the perennial spring (39 ± 21) % and stormwater runoff from irrigated areas (18 ± 17) % were the major streamflow sources in the rainy season. Streamflow sources in the dry season were different upstream and downstream, thereby reflecting different water use dynamics in the catchment. In the upstream catchment, the perennial spring at the river source (65 ± 15) % and irrigation return flows (35 ± 15) % were the dominant streamflow sources. In the downstream part of the catchment, dry season streamflow was mainly attributed to irrigation return flows (73 ± 15) % and wastewater (27 ± 15) %, both associated with water originally transferred in from the adjacent Kafue River through an intra-basin water transfer scheme. It was found that this water plays an important role in sustaining streamflow in the lower part of the catchment before discharging back into the Kafue River. It was thus recommended that efforts to improve irrigation efficiency in the lower catchment must simultaneously ensure downstream flows are maintained. Based on the findings of the past and present interactions, it was noted that irrigated agriculture had two contrasting effects on dry season flows depending on the source of irrigation water. In the upper and middle catchment where irrigation water was sourced from the Kaleya River, irrigation reduced dry season flows despite some contributions from return flows. In the downstream part of the catchment where irrigation water comes from the neighbouring Kafue River (intra-basin transfer), irrigation increased dry season flows through return flow contributions to the lower Kaleya River. Having better understood the climatic-landscape-hydrological interactions of the past and present, the potential future changes in climate and their effects on blue water flow (streamflow), green water flow (evapotranspiration – ET) and sediment load were evaluated. This was aimed at getting a holistic overview of the interactions so that management interventions could anticipate the future changes as this is necessary for long-lasting beneficial effects. Two Global Climate Models (GCMs) [MICROC5 and MPI-ESM-LR] and an ensemble (mean) dataset from five GCMs that had the highest Nash Sutcliffe Efficiency (≥ 0.29) and Heidke skill score (≥ 85%) for the Kaleya River Catchment were used to account for uncertainties in GCMs. The Soil and Water Assessment Tool (SWAT) hydrological model was calibrated and applied stochastically (to account for parameter uncertainty) and used to evaluate impacts of climate change on streamflow, ET, and sediment load. The period 1970 – 2005 was used as the baseline, while 2021 – 2050 was the future. Results based on the ensemble (mean) predicted a 6% and 12% increase in annual rainfall and a 1˚C and 2˚C increase in temperature compared to the baseline under the RCP 4.5 and RCP 8.5 scenarios, respectively. These changes were also accompanied by predicted increase in rainfall intensities. It was further predicted that maximum one-day rainfall would increase by 3% and 20% under the RCP 4.5 and RCP 8.5 scenarios, respectively. Additionally, the GCMs generally predicted increased number of Consecutive Dry Days (dry spell length) by about 2%–10% over the baseline. Taking the median (M95PPU – defined as the 50% uncertainty level for the hydrological model), and the GCMs ensemble mean climate, a 31% (9,675 m3 day -1) increase in annual streamflow was predicted under the RCP 8.5, accompanied by a sediment load increase of 144% (2,175 tonnes year-1) over the baseline. For the RCP 4.5 scenario, streamflow was predicted to increase by 21% (4,523 m3 day -1), accompanied by sediment load increase of 65% (994 tonnes year -1). With respect to green water flows, there was a predicted 2% (9mm) increase in annual ET under the RCP 4.5 scenario, and no change under the RCP 8.5 scenario. While climate change was predicted to increase water availability in both the rainy and dry seasons, landcover change could reverse the potential blue water gains in the dry season and reduce green water storage by about 13%. Further, the study evaluated the efficiency of Nature-based Solutions (NbSs) for managing increased rainfall intensities and the predicted increase in rainy season surface runoff and sediment load under different climate change scenarios. The NbSs virtual experiments were conducted using SWAT in SWAT-CUP. The reforestation NbS predicted the largest reductions in surface blue water (surface runoff) by 74% under the historical climate, 69% under the RCP 4.5 and 62% under the RCP 8.5 climate scenarios. Reforestation further resulted in predicted increase in deep aquifer recharge by 39% (historical), 26% (RCP 8.5 scenario) and 23% (RCP 4.5). Additionally, it was predicted that baseflow contribution to streamflow would increase by 11% (historical) and 2% (RCP 8.5) but not under the RCP 4.5 scenario (-2%). Green water flows (evapotranspiration) were predicted to increase by 3% (both RCP 4.5 and RCP 8.5%) and 2% (historical). Under the recharge structures NbS, it was predicted that surface runoff would reduce by about 2 - 4%, baseflow contribution to streamflow and deep aquifer recharge would increase by about 4%, without any change in ET under all climate scenarios. Conservation tillage NbS had a negligible predicted effect on water balance components at a catchment scale, suggesting that the water benefits could mainly be at a field scale. However, the effects of Conservation tillage on sediment load were noticeable even at a catchment scale. On sediment load, the highest change was predicted under the recharge structures NbS (-34% historical, -24% RCP 4.5 and -15% RCP 8.5 scenario), followed by reforestation (-15% historical, -7% RCP 4.5 scenario and -6% RCP 8.5 scenario) and conservation tillage (-4% historical, -2% RCP 4.5 and -1% RCP 8.5 scenario). From the green-blue water perspective, it was concluded that these nature-based solutions could assist in managing the increased rainfall and its intensities, and the ensuing high rainy season surface runoff and sediment load. The NbSs could thus assist in storing rainwater in the catchment for longer periods by converting it to deep groundwater, and baseflow and increasing the productive green water flows. The NbS could also be effective in sediment load management. In conclusion, the interactions of the changing landscape patterns with the changing climate and weather extremes and the effects on local green and blue water availability were investigated in this study. Overall, the study found that landscape pattern changes (patchiness of cover in addition to percentage of cover) amplify the negative effects of the changing climatic and weather extremes in the past, present, and future periods. But if well designed in form of NbS interventions, the landscape patterns could be used to manage the effects of climate change whereby the increasing rainfall intensities could be taken as a resource (not a case) for improving local water storage, and productivity. This could assist in building resilience to other climatic extremes such as dry spells, rainfall variability and increasing air temperatures.German Academic Exchange Service (DAAD)Biochemistry, Genetics and Microbiology (BGM)PhD (Water Resource Management)Unrestricte

Africa: Atlas of Our Changing Environment

This comprehensive atlas provides data, satellite imagery, and analysis of the environmental conditions and issues relevant to each African country, and several surrounding island nations. The atlas also covers trans-border international issues in Africa

Constraints on tree growth, impacts of tropical cyclones and outcomes of community management in the Miombo woodlands

The Miombo woodlands of southern Africa are a globally significant store of carbon (C) and biodiversity. They also provide services for more than 150M people across several of the world’s most economically impoverished countries. The Miombo woodlands are dynamic, with extensive resource loss accompanied by areas of regrowth and increase. Disturbance processes, both from natural processes and widespread anthropogenic activities, are critical in maintaining woody biomass in these ecosystems, although intensity of disturbance varies widely. Increase in woody biomass has been observed in the Miombo, though the drivers of this trend are uncertain and the fundamental constraints on trees and woodlands not well understood. Ultimately, both losses and gains can be difficult to detect and hard to attribute to a particular cause. The aim of this thesis is to use field data and remote sensing to add to understanding of the constraints on tree populations in the Miombo and the impacts of severe environmental disturbances and management interventions on woodland structure. Tree growth is a crucial demographic rate in African woodlands and plays a key role in shaping woodland structure and C cycling. However, observations of tree growth are relatively lacking in the Miombo and the determinants of tree growth rates are poorly known. In Chapter 2 I use data collected from long-term monitoring of permanent sample plots in Mozambique and Tanzania and linear mixed modelling to estimate tree growth increments and assess the relative importance of different determinants of tree growth. The estimated growth (diameter increment) in these plots was 1.8 ± 0.17 mm/yr. Climate and edaphic factors explained little variation in tree growth. Tree-tree competition was found to be a significant constraint on growth (trees in experiencing competition levels in the top 5% of values grew 1.24 ± 0.08 mm/yr slower on average than those in the bottom 5%) as was stem wounding (wounded trees grew 0.84 ± 0.04 mm/yr slower). Root symbioses (both fungal and bacterial symbionts) which aid in the uptake of nutrients were found to have a strong positive impact on growth, particularly ectomycorrhizal associations which are common to dominant species in the Miombo. The impacts of tree-tree competition and nutrient symbioses are poorly represented in biogeochemical models in these ecosystems but this analysis suggests they are critical, whilst the subtle impacts of human interaction with trees (through wounding) are also possibly underappreciated. Tropical Cyclones can have substantial long-term impacts on woodland structure in affected areas and projections indicate that the impacts of Cyclones will increase in southeastern Africa over the coming century. There are few studies which have documented the immediate impacts or long-term responses of woodland ecosystems to this damage. In Chapter 3 I analyse data from a survey of eight permanent sample plots setup explicitly to assess the damage caused by Cyclone Idai to in woodlands in Gorongosa National Park, central Mozambique. It is found that Cyclone Idai caused damage primarily to large trees, thus whilst only 2% of trees were felled these individuals represented 8.5% of overall basal area. The implications of this damage are discussed in context of the constraints on trees in these woodlands, and whilst the damage is severe it is concluded that the outcomes are highly uncertain. Whilst damage from the cyclone is substantial, detecting change in woodland structure is challenging in these ecosystems. In Chapter 4 I explore the possibility of upscaling field observations of treefall occurrence using data from a small unmanned aerial vehicle (drone) and satellite radar. Drone survey produced comparable estimates of treefall intensity to the PSP observations (in terms of fallen number of stems, fallen basal area and carbon) and allowed survey of 155 ha, capturing widespread damage across the study area. In the study area radar backscattering intensity in C-Band radar reduced in the two years after the cyclone relative to the two years before whilst interferometric coherence increased - both in agreement with radar theory - although backscattering intensity in L-Band radar increased. Whilst significant relationships were identified between change in radar data and the intensity of damage in drone surveys, there appears to be limited ability to map variations in treefall intensity across the wider landscape using this method, or to determine areal impacts on above ground C thereafter. It is concluded that repeat analysis may yield better results however. In Tanzania, Village Land Forest Reserves (VLFRs, a form of participatory forest management) aim to promote sustainable profit from woodland resources, although the impact of VLFRs on land cover change rates is uncertain. In Chapter 5 I use satellite radar to map deforestation and a degradation across an area of southern Tanzania from 2010-2018 and statistical matching to compare rates of land cover change within a sample of VLFRs to woodlands under comparable resource pressure outside VLFRs or other protection status. It is found that VLFRs in the majority of cases were very effective in reducing deforestation (with five of seven having rates close to zero) and also reduced degradation rates (though to a lesser degree). Increasing density of woody biomass in forested areas was observed in all VLFRs, but varied widely across the sample (from 0.2 - 1.5 tC ha yr-1) and was in five of seven VLFRs below that observed in woodland areas with no protection status in this region (+0.7 tC ha yr-1). Whilst it appears that VLFR establishment achieved its intended goal of sustainable profit from woodlands resources from 2010-2018, further work is required to understand variation in outcome across the observed sample. This methodology however shows promise in continued assessment of VLFR performance for this purpose

Estudo sobre incêndios florestais na Floresta de Miombo Reserva do Niassa-Moçambique, com base em dados de sensoriamento remoto

Os incêndios florestais são um dos principais fatores recorrentes de danos ambientais, sociais e econômicos na Reserva do Niassa. A presente pesquisa teve como objetivo entender os fatores causais e os padrões de ocorrência dos incêndios florestais na Reserva do Niassa-Moçambique, com base no conhecimento prévio do padrão de distribuição espacial e da dinâmica temporal da cobertura vegetal, utilizando dados MODIS, entre o período de 2001 a 2015. Para tal foram utilizadas bases de dados, de diferentes produtos do sensor MODIS (Moderate Resolution Imaging Spectroradiometer): produto MOD13Q1 (índice de vegetação NDVI - Normalized Difference Vegetation Index); produto MCD14ML (Fogo ativo); produto MCD64A1 (Área queimadas). Os dados meteorológicos de precipitação pluvial foram obtidos do Climate Hazards group InfraRed Precipitation with Station data (CHIRPS), a temperatura média do ar do ERA Interim; e umidade relativa foi calculada com base na equação da FAO-Penman-Monteith. Foram utilizados ainda dados topográficos (Modelo Digital de Terreno) do Shuttle Radar Topographic Mission (SRTM) para o cálculo de elevação, declividade e exposição solar. Os dados de vias de acesso e dos assentamentos populacionais foram produzidos pela CENACARTA (Centro Nacional de Cartografia e Teledeteção-Moçambique). O uso de séries temporais de dados NDVI /MODIS permitiu obter informações sobre a fenologia da vegetação, identificar diferentes tipos de cobertura vegetal da Reserva e analisar a sua dinâmica e variabilidade espaço-temporal. A sazonalidade da vegetação da Reserva apresenta ciclos bem marcados com baixos valores na estação seca e valores altos na estação chuvosa. Para análise dos padrões espaço-temporais dos incêndios florestais foram utilizados os produtos MCD14ML (Fogo ativo) e MCD64A1 (Área queimada), utilizando a estatística descritiva, análise de tendência e a densidade de Kernel. Foi observado que os incêndios florestais ocorrem entre os meses de agosto a outubro, período de maior ocorrência, e com uma dinâmica espacial que inicia a leste e se desloca para o oeste. Os incêndios ocorrem predominantemente nas florestais decíduas e de montanha. Foi também utilizada à regressão logística para a modelagem de ocorrência de incêndio florestal, com vista à identificação de locais de maior ocorrência de incêndios florestais, e identificação de fatores determinantes para a sua ocorrência. Os resultados revelaram que os principais fatores determinantes para ocorrência dos incêndios florestais na Reserva do Niassa, entre 2001 e 2015, foram fundamentalmente: cobertura vegetal, seguida de temperatura do ar e da elevação. A área de maior ocorrência de incêndios é a zona leste da Reserva. Os resultados obtidos permitiram concluir que a cobertura vegetal é um dos fatores fundamentais da ocorrência de incêndio nas florestais de Miombo. O uso dos dados MODIS, índice de vegetação, focos de incêndio e áreas queimadas demonstrou potencial no estudo de incêndios florestais na Reserva do Niassa.Forest fires are one of the main recurring factors of environmental, social and economic damages in Niassa Reserve. The objective of the present research was to understand the causal factors and patterns of occurrence of forest fires in Niassa-Mozambique Reserve, based on prior knowledge of the spatial distribution pattern and temporal dynamics of the vegetation cover using MODIS data between the period from 2001 to 2015. For this purpose, the following databases were used: MODIS sensor (Moderate Resolution Imaging Spectroradiometer): MOD13Q1 (Normalized Difference Vegetation Index); MCD14ML product (active fire); product MCD64A1 (burned area). Meteorological data on rainfall were obtained from the Climate Hazards group InfraRed Precipitation with Station data (CHIRPS), and the average air temperature of ERA Interim; The relative humidity was calculated based on FAO-Penman-Monteith equation. Topographic data (Digital Terrain Model) of the Shuttle Radar Topographic Mission (SRTM) were used for the calculation of elevation, slope and sun exposure. Data on access routes and population settlements were produced by CENACARTA (National Center for Cartography and Teledetection-Mozambique). The use of NDVI / MODIS temporal data series allowed us to obtain information on vegetation phenology, to identify different types of vegetation cover of the Reserve and to analyze its dynamics and spatio-temporal variability. The seasonality of the Reserve vegetation shows well marked cycles with low values in the dry season and high values in the rainy season. For the analysis of spatiotemporal patterns of forest fires, the products MCD14ML (Active fire) and MCD64A1 (Burned area) were used, using descriptive statistics, trend analysis and Kernel density. It was observed that forest fires occur between August and October, the period of greatest occurrence, and with a spatial dynamics that begins in the east and moves to the west. Fires occur predominantly in deciduous and mountain forests. It was also used logistic regression for modeling of occurrence of forest fire, with a view to the identification of sites of greater occurrence of forest fires, and identification of factors determining its occurrence. The results showed that the main determining factors for the occurrence of forest fires in Niassa Reserve between 2001 and 2015 were fundamentally: vegetation cover, followed by air temperature and elevation. The area with the highest occurrence of fires is the eastern zone of the Reserve. The results obtained allowed to conclude that the vegetation cover is one of the fundamental factors of the fire occurrence in Miombo forest. The use of MODIS data, vegetation index, active fire and burned areas showed potential in the study of forest fires in Niassa Reserve

Above-ground carbon stocks, species diversity and fire dynamics in the Bateke Plateau

Savannas are heterogeneous systems characterised by a high spatial and temporal variation in ecosystem structure. Savannas dominate the tropics, with important ecological functions, and play a prominent role in the global carbon cycle, in particular responsible for much of its inter-annual variability. They are shaped by resource availability, soil characteristics and disturbance events, particularly fire. Understanding and predicting the demographic structure and woody cover of savannas remains a challenge, as it is currently poorly understood due to the complex interactions and processes that determine them. A predictive understanding of savanna ecosystems is critical in the context of land use management and global change. Fire is an essential ecological disturbance in savannas, and forest-savanna mosaics are maintained by fire-mediated positive feedbacks. Over half of the world’s savannas are found in Africa, and over a quarter Africa’s surface burns every year, with fires occurring principally in the savanna biome. These have strong environmental and social impacts. Most fires in Africa are anthropogenic and occur during the late dry season, but their dynamics and effects remain understudied. The main objective of this research is to understand the floristic composition, carbon storage, woody cover and fire regime of the mesic savannas of the Bateke Plateau. The Bateke Plateau is savanna-forest mosaic ecosystem, situated mainly in the Republic of Congo, with sandy Kalahari soils and enough precipitation for potential forest establishment (1600 mm/yr). Despite occupying 89,800 km2, its ecology and ecosystem functions are poorly understood. This study combines two approaches: firstly experimental, setting up long term field experiments where the fire regime is manipulated, and then observational, using remote sensing to estimate the carbon storage and study the past history of the fire regime in the region. I established four large (25 ha) plots at two savanna sites, measured their carbon stocks, spatial structure and floristic composition, and applied different annual fire treatments (early and late dry season burns). These treatments were applied annually during 3 years (2015, 2016 and 2017), and the plots were re-measured every year to estimate tree demographic rates and the identification of the key processes that impact them, including fire and competition. Field data were combined with satellite radar data from ALOS PALSAR, and the fire products of the MODIS satellites, to estimate carbon stocks and fire regimes for the entire Bateke Plateau. I also analyse the underlying biophysical and anthropogenic processes that influence the patterns in Above-Ground Woody Biomass (AGWB) and their spatial variability in the Bateke landscape. The total plant carbon stocks (above-ground and below-ground) were low, averaging only 6.5 ± 0.3 MgC/ha, with grass representing over half the biomass. Soil organic matter dominate the ecosystem carbon stocks, with 16.7 ± 0.9 Mg/ha found in the top 20 cm alone. We identified 49 plant species (4 trees, 13 shrubs, 4 sedges, 17 forbs and 11 grass species), with a tree hyperdominance of Hymenocardia acida, and a richer herbaceous species composition. These savannas showed evidence of tree clustering, and also indications of tree-tree competition. Trees had low growth rates (averaging 1.21 mm/yr), and mortality was relatively low (3.24 %/yr) across all plots. The experiment showed that late dry season fires significantly reduced tree growth compared to early dry season fires, but also reduced stem mortality rates. Results show that these mesic savannas had very low tree biomass, with tree cover held far below its climate potential closed-canopy maximum, likely due to nutrient poor sandy soils and frequent fires. Results from the remote sensing analysis indicated that multiple explanatory variables had a significant effect on AGWB in the Bateke Plateau. Overall, the frequency of fire had the largest impact on AGWB (with higher fire frequency resulting in lower AGWB), with sand content the next most important explanatory variable (with more sand reducing AGWB). Fires in the Bateke are very frequent, and show high seasonality. The proportion of fires that occurred in the late dry season, though smaller predictor, was also more important than other factors (including soil carbon proportion, whether or not the savanna area was in a protected area, annual rainfall, or distance to the nearest town, river or road), with a larger proportion of late dry season fires associated with a small increase in AGWB. The results give pointers for management of the savannas of the Bateke Plateau, as well as improving our understanding of vegetation dynamics in this understudied ecosystem and help orient policy and conservation