- I am a Chief Research Scientist of the Forestry Research Institute of Ghana (FORIG) of the Council for Scientific and... moreI am a Chief Research Scientist of the Forestry Research Institute of Ghana (FORIG) of the Council for Scientific and Industrial Research (CSIR), a Professor at the CSIR College of Science and Technology (Affiliated to the University of Cape Coast, Ghana), and was Deputy Director of FORIG from January 2013 to June 2015. I also lecture at the Climate Change and Land Use Doctoral programme (WASCAL) of the Civil Engineering Department of the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
I obtained my BSc degree in Natural Resources Management from the then University of Science and Technology, Kumasi, Ghana in 1988. I proceeded to Nagoya University, Japan to pursue graduate programmes and obtained Master and Doctoral degrees in Agricultural Sciences, majoring in Forestry, in 1994 and 1997, respectively. I have been engaged in research and teaching, but skewed towards research.
My research work is focused on System Ecology, Site Productive Capacity of Planted Forest, and Climate Change Related Research in the Agriculture, Forestry and Other Land Uses (AFOLU) sector. I have been collaborating with some universities in Europe and elsewhere in various research work. Notably among them are University of Oxford, University of Liverpool, University of Exeter, University of Birmingham and University of Pretoria. I have just established and carried out forest carbon inventory in 38 1-ha Permanent Sample Plots covering all the eco-climatic zones of Ghana, under the auspices of the Food and Agricultural Organization of the United Nations. With the exception of Sahel Savannah, the eco-climatic zones of Ghana is almost a reflection of that of West Africa. In collaboration with University of Exeter a 50-ha plot have been established in the Wet Evergreen zone, and variety of assessments being carried out.edit
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Stem straightness, axis persistence, presence/absence of protuberant buds and epicormics, diameter and height have profound influence on timber quality and volume of teak (Tectona grandis). Provenance trials of teak were established in... more
Stem straightness, axis persistence, presence/absence of protuberant buds and epicormics, diameter and height have profound influence on timber quality and volume of teak (Tectona grandis). Provenance trials of teak were established in the 1970s in Ghana, as part of the Food and Agriculture Organization (FAO) International Series of Provenance Trials, with the view of selecting teak germplasm for sites with specific environmental conditions. Two field trials were located in dry semi-deciduous (dry) and moist semi-deciduous (moist) ecological zones of Ghana. They consisted of 13 provenances, including four landraces each from Ghana and Indonesia, and two and three provenances from India and Laos, respectively. Trees were assessed at 9, 17 and 28 years to (1) quantify the potential variation in quality and timber volume production, (2) examine possibilities for determining early selection of parameters of superior provenances and (3) select provenances for sites with particular environmental conditions. Production traits were higher on the moist site than the dry site. Mean height was 23.2 and 20.2 m tree−1, stem cross-sectional area at breast height was 0.0896 and 0.0474 m2 tree−1, and stem volume was 0.75 and 0.34 m3 tree−1 for the moist and dry sites, respectively. Nilambur provenance from moist India had the highest mean stem straightness score of 19% above average, whereas Savannakhet from Laos had the best protuberant bud score with 18% of the trees above average. Indonesian landraces performed better in the dry zone, whereas provenances from India and Laos performed better in the moist zone. Phenotypic correlations between age 9 and 28 years were moderate (r 0.54–0.90) to high (r > 0.90) for production and qualitative characteristics, indicating feasibility of early assessment for identification of superior provenances. Nilambur and Savannakhet II provenances proved to be favourable choices for the moist zone, whereas the Temandsang provenance from Indonesia was found to be the best choice for the dry site.
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2Tropical forests cover large areas of equatorial Africa and play a significant role in the global carbon cycle. However, there has been a lack of in-situ measurements to understand the forests’ gross and net primary productivity (GPP and... more
2Tropical forests cover large areas of equatorial Africa and play a significant role in the global carbon cycle. However, there has been a lack of in-situ measurements to understand the forests’ gross and net primary productivity (GPP and NPP) and their allocation. Here we present the first detailed field assessment of the carbon budget of multiple forest sites in Africa, by monitoring 14 one-hectare plots along an aridity gradient in Ghana. When compared with an equivalent aridity gradient in Amazonia using the same measurement protocol, the studied West African forests generally had higher GPP and NPP and lower carbon use efficiency (CUE). The West African aridity gradient consistently shows the highest NPP, CUE, GPP, and autotrophic respiration at a medium-aridity site, Bobiri. Notably, NPP and GPP of the site are the highest yet reported anywhere in the tropics using similar methods. Widely used data products (MODIS and FLUXCOM) substantially underestimate productivity when comp...
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Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the... more
Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface.
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Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to... more
Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non‐forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo include...
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Animals, such as termites, have largely been overlooked as global-scale drivers of biogeochemical cycles1,2, despite site-specific findings3,4. Deadwood turnover, an important component of the carbon cycle, is driven by multiple decay... more
Animals, such as termites, have largely been overlooked as global-scale drivers of biogeochemical cycles1,2, despite site-specific findings3,4. Deadwood turnover, an important component of the carbon cycle, is driven by multiple decay agents. Studies have focused on temperate systems5,6, where microbes dominate decay7. Microbial decay is sensitive to temperature, typically doubling per 10°C increase (decay effective Q10 = ~2)8–10. Termites are important decayers in tropical systems3,11–13 and differ from microbes in their population dynamics, dispersal, and substrate discovery14–16, meaning their climate sensitivities also differ. Using a network of 133 sites spanning 6 continents, we report the first global field-based quantification of temperature and precipitation sensitivities for termites and microbes, providing novel understandings of their response to changing climates. Temperature sensitivity of microbial decay was within previous estimates. Termite discovery and consumption...
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The colour of teak wood from plantations in Ghana was characterized by the International Commission on Illumination (CIE) L* a* b* colour measurement system in order to study the variations of wood colour parameters (lightness-darkness,... more
The colour of teak wood from plantations in Ghana was characterized by the International Commission on Illumination (CIE) L* a* b* colour measurement system in order to study the variations of wood colour parameters (lightness-darkness, redness-greenness and yellowness-blueness), among the different ecological zones. Teak trees totaling 46 were felled from 8 different plantation stands in four different
ecological zones of Ghana (moist semi-deciduous forest, MSDF; dry semi-deciduous forest, DSDF; transition savanna forest; and savanna forest). Colour measurements were made on strips obtained from logs cut from the felled trees. Chemical analyses were performed on soil samples obtained from the rooting zones of the teak trees. Both environmental and tree age effects on colour were observed. However, environmental factors had a stronger effect on the colour of teak heartwood than the stand age. Although there were no significant differences between teak wood colour in moist semi-deciduous forest and transition savanna forest on one hand, and dry semi-deciduous forest and savanna forest on the other hand, in general, environment seemed to be an important factor, with teak wood colour being relatively darker in wetter areas than drier ones. Wood colour parameters showed differing relationships with soil chemical properties ranging from no relation through weak to moderate relations. For instance, soil pH decreased moderately with decreasing L* values (increasing darkness), indicating some evidence that teak wood colour may be predicted from soil pH. However, there was very little evidence that teak wood colour could be predicted from soil exchangeable cations (Ca2+, Mg2+, Na+ and K+). The range of observed site quality was rather limited. Nevertheless, richer plantation sites showed a tendency toward darker and less red heartwood.
ecological zones of Ghana (moist semi-deciduous forest, MSDF; dry semi-deciduous forest, DSDF; transition savanna forest; and savanna forest). Colour measurements were made on strips obtained from logs cut from the felled trees. Chemical analyses were performed on soil samples obtained from the rooting zones of the teak trees. Both environmental and tree age effects on colour were observed. However, environmental factors had a stronger effect on the colour of teak heartwood than the stand age. Although there were no significant differences between teak wood colour in moist semi-deciduous forest and transition savanna forest on one hand, and dry semi-deciduous forest and savanna forest on the other hand, in general, environment seemed to be an important factor, with teak wood colour being relatively darker in wetter areas than drier ones. Wood colour parameters showed differing relationships with soil chemical properties ranging from no relation through weak to moderate relations. For instance, soil pH decreased moderately with decreasing L* values (increasing darkness), indicating some evidence that teak wood colour may be predicted from soil pH. However, there was very little evidence that teak wood colour could be predicted from soil exchangeable cations (Ca2+, Mg2+, Na+ and K+). The range of observed site quality was rather limited. Nevertheless, richer plantation sites showed a tendency toward darker and less red heartwood.
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This article reports on a study conducted to assess the carbon storage potential of Bambusa vulgaris, the predominant bamboo species in Ghana. The study aimed to fill a knowledge gap on the potential of bamboo to sequester carbon for... more
This article reports on a study conducted to assess the carbon storage potential of Bambusa vulgaris, the predominant bamboo species in Ghana. The study aimed to fill a knowledge gap on the potential of bamboo to sequester carbon for climate change mitigation in Ghana. Unlike previous studies that only focused on aboveground biomass, this study assessed belowground, litter, and coarse wood carbon pools. Allometric parameters and models were used to measure the aboveground biomass, while other carbon pools were directly measured. The results showed that the aboveground biomass of B. vulgaris had a carbon stock of 42.85 ± 9.32 Mg C ha−1, which was 73% of the total biomass carbon stock. The carbon stocks of belowground, coarse wood and litter were 8.57, 3.02, and 4.25 Mg C ha−1, respectively. The study also found that B. vulgaris had a high carbon dioxide sequestration potential of 215.39 Mg CO2e ha−1 compared to 147–275 Mg CO2e ha−1 for trees in general. The findings suggest that B. v...
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Biomass carbon stocks (BCS) and soil carbon stocks (SCS) are key parameters for estimating carbon balance in tropical Savannah woodlands. However, BCS and SCS are not only poorly quantified in the Savannah agro-ecological zone in Ghana,... more
Biomass carbon stocks (BCS) and soil carbon stocks (SCS) are key parameters for estimating carbon balance in tropical Savannah woodlands. However, BCS and SCS are not only poorly quantified in the Savannah agro-ecological zone in Ghana, West Africa, environmental variables modulating the spatial distribution of BCS and SCS are little understood. In this study, BCS and SCS across 61 farmlands randomly established in the Savannah agro-ecological zone in Ghana were quantified and examined simultaneously to determine the relative importance of site condition, soil chemical and soil physical properties on variation in the distribution of carbon stocks. Site condition, soil chemical and physical properties together explained 76.4% of the total variation in carbon stocks. Specifically, soil chemical properties alone explained 67.5% of the total variation in carbon stocks, while site condition and soil physical properties explained only 0.9% and 0.8% of the variation in carbon stocks, respectively. The importance of soil chemical properties on the distribution of carbon stocks in farmlands in the savannah agro-ecological zone was largely due to significant positive relationship between SCS and total nitrogen (TN) (r = 0.92, p = 0.000) and total exchangeable bases (TEB), particularly potassium (K ex) (r = 0.45, p = 0.007), sodium (Na) (r = 0.41, p = 0.006) and calcium (Ca) (r = 0.30, p = 0.049). The results suggest the need for agronomic practices to enhance soil carbon stocks in croplands since accumulation of soil organic matter is crucial for nutrient release, moisture retention, soil fertility and ultimately productivity and crop yields.
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Research Interests: Earth Sciences, Coffee, Biology, Agroforestry, Carbon Sequestration, and 15 moreBiological Sciences, Environmental Sciences, Allometry, Stems, Aboveground biomass, Tree Allometry, Foliage, Specific Gravity, Coffea arabica, Dry Matter, Agroforestry Systems, Agroforestry System, Plant Height, Branches, and Basal Area
Summary(1)The research conducted, including the rationaleThe direct effect of aridity on photosynthetic and water-transport strategies is not easy to discern in global analyses because of large-scale correlations between precipitation and... more
Summary(1)The research conducted, including the rationaleThe direct effect of aridity on photosynthetic and water-transport strategies is not easy to discern in global analyses because of large-scale correlations between precipitation and temperature. We analyze tree traits collected along an aridity gradient in Ghana, West Africa, that shows little temperature variation, in an attempt to disentangle thermal and hydraulic influences on plant traits.(2)MethodsPredictions derived from optimality theory of the variation of key plant traits along the gradient are tested with field measurements.(3)ResultsMost photosynthetic traits show trends consistent with optimality-theory predictions, including higher photosynthetic rates in the drier sites, and an association of higher photosynthetic rates with greater respiration rates and greater water transport. Leaf economic and hydraulic traits show less consistency with theory or global-scale pattern, especially predictions based on xylem effi...
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We analysed thirty-five 400-m2 plots encompassing forest, savanna and intermediate vegetation types in an ecotonal area in Ghana, West Africa. Across all plots, fire frequency was over a period of 15 years relatively uniform (once in 2–4... more
We analysed thirty-five 400-m2 plots encompassing forest, savanna and intermediate vegetation types in an ecotonal area in Ghana, West Africa. Across all plots, fire frequency was over a period of 15 years relatively uniform (once in 2–4 years). Although woodlands were dominated by species typically associated with savanna-type formations, and with forest formations dominated by species usually associated with closed canopies, these associations were non-obligatory and with a discrete non-specialized species grouping also identified. Across all plots, crown area index, stem basal area and above-ground biomass were positively associated with higher soil exchangeable potassium and silt contents: this supporting recent suggestions of interplays between potassium and soil water storage potential as a significant influence on tropical vegetation structure. We also found an average NDVI cover increase of ~0.15% year−1 (1984–2011) with plots dominated by non-specialized species increasing ...
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The dataset attached was produced and analysed in the undertaking of the study "Aboveground Biomass and Vegetative Carbon Dioxide Sequestration of Bambusa vulgaris in Ghana's Bobiri Forest". The study aimed to estimate the... more
The dataset attached was produced and analysed in the undertaking of the study "Aboveground Biomass and Vegetative Carbon Dioxide Sequestration of Bambusa vulgaris in Ghana's Bobiri Forest". The study aimed to estimate the vegetative carbon stock of B. vulgaris, the most widespread bamboo species in Ghana, by determining the aboveground biomass and the carbon stocks in the vegetative carbon pools (aboveground, belowground, coarse woody (dead bamboo), and litter. The study was conducted in the Bobiri Forest Reserve. Compartment information has been presented in the compartment tab in the data file attached. The dataset comprises raw and processed data from the three carbon pools measured i.e. aboveground biomass, coarse woody debris, and litter pool. The aboveground biomass was measured for n = 2,114 and the parameters were the clump dimensions (length and breadth), number of culms per clump, age of each culm per clump, diameter at breast height, and the stand area. Sam...
Raw data for the Kogyae Plot 2 (Transition plot) pollen surface sample dataset obtained from the Neotoma Paleoecology Database.
Raw data for the Bobiri (BOB01) pollen surface sample dataset obtained from the Neotoma Paleoecology Database.
The most diverse and abundant family of termites, the Termitidae, evolved in African tropical forests. They have since colonised grassy biomes such as savannas. These open environments have more extreme conditions than tropical forests,... more
The most diverse and abundant family of termites, the Termitidae, evolved in African tropical forests. They have since colonised grassy biomes such as savannas. These open environments have more extreme conditions than tropical forests, notably wider extremes of temperature and lower precipitation levels and greater temporal fluctuations (of both annual and diurnal variation). These conditions are challenging for soft-bodied ectotherms, such as termites, to survive in, let alone become as ecologically dominant as termites have. Here, we quantified termite thermal limits to test the hypothesis that these physiological limits are wider in savanna termite species to facilitate their existence in savanna environments. We sampled termites directly from mound structures, across an environmental gradient in Ghana, ranging from wet tropical forest through to savanna. At each location we quantified both Critical Thermal Maximum (CTmax ) and Critical Thermal Minimum (CTmin ) of all the most abundant mound-building Termitidae species in the study areas. We modelled the thermal limits in two separate mixed effects models against: canopy cover at the mound, temperature and rainfall, as fixed effects, with sampling location as a random intercept. For both CTmax and CTmin savanna species had significantly more extreme thermal limits than forest species. Between and within environments, areas with higher amounts of canopy cover were significantly associated with lower CTmax values of the termite colonies. CTmin was significantly positively correlated with rainfall. Temperature was retained in both models, however it did not have a significant relationship in either. Sampling location explained a large proportion of the residual variation, suggesting there are other environmental factors that could influence termite thermal limits. Our results suggest that savanna termite species have wider thermal limits than forest species. These physiological differences, in conjunction with other behavioural adaptations, are likely to have enabled termites to cope with the more extreme environmental conditions found in savanna environments and facilitated their expansion into open tropical environments.
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Raw data for the Kogyae Plot 1 (Forest plot) pollen surface sample dataset obtained from the Neotoma Paleoecology Database.
Raw data for the Ankasa (ANK02) pollen trap dataset obtained from the Neotoma Paleoecology Database.
Raw data for the Bobiri (BOB01) pollen trap dataset obtained from the Neotoma Paleoecology Database.
Raw data for the Kogyae Plot 3 (Savannah plot) pollen surface sample dataset obtained from the Neotoma Paleoecology Database.
Meteorological extreme events such as El Niño events are expected to affect tropical forest net primary production (NPP) and woody growth, but there has been no large-scale empirical validation of this expectation. We collected a large... more
Meteorological extreme events such as El Niño events are expected to affect tropical forest net primary production (NPP) and woody growth, but there has been no large-scale empirical validation of this expectation. We collected a large high temporal resolution dataset (for 1–13 years depending upon location) of more than 172 000 stem growth measurements using dendrometer bands from across 14 regions spanning Amazonia, Africa and Borneo in order to test how much month-to-month variation in stand-level woody growth of adult tree stems (NPP<sub>stem</sub>) can be explained by seasonal variation and interannual meteorological anomalies. A key finding is that woody growth responds differently to meteorological variation between tropical forests with a dry season (where monthly rainfall is less than 100 mm), and aseasonal wet forests lacking a consistent dry season. In seasonal tropical forests, a high degree of variation in woody growth can be predicted from seasonal variatio...
Research Interests: Africa, Biomass, Productivity, Ecology, Global Change Biology, and 15 moreMedicine, Biological Sciences, Biodiversity Conservation, Environmental Sciences, Forests, Rainforest, Plant Roots, Amazon forest, Ecosystem, Science Technology, Litter Production, Allocation, Aluminum Toxicity, Residence Time, and NET PRIMARY PRODUCTIVITY
Above-ground biomass and structure of 260 African tropical forests 20120295 S. L. Lewis, B. Sonke, T. Sunderland, S. K. Begne, G. Lopez-Gonzalez, G. M. F. van der Heijden, O. L. Phillips, K. Affum-Baffoe, T. R. Baker, L. Banin, J.-F.... more
Above-ground biomass and structure of 260 African tropical forests 20120295 S. L. Lewis, B. Sonke, T. Sunderland, S. K. Begne, G. Lopez-Gonzalez, G. M. F. van der Heijden, O. L. Phillips, K. Affum-Baffoe, T. R. Baker, L. Banin, J.-F. Bastin, H. Beeckman, P. Boeckx, J. Bogaert, C. De Canniere, E. Chezeaux, C. J. Clark, M. Collins, G. Djagbletey, M. N. K. Djuikouo, V. Droissart, J.-L. Doucet, C. E. N. Ewango, S. Fauset, T. R. Feldpausch, E. G. Foli, J.-F. Gillet, A. C. Hamilton, D. J. Harris, T. B. Hart, T. de Haulleville, A. Hladik, K. Hufkens, D. Huygens, P. Jeanmart, K. J. Jeffery, E. Kearsley, M. E. Leal, J. Lloyd, J. C. Lovett, J.-R. Makana, Y. Malhi, A. R. Marshall, L. Ojo, K. S.-H. Peh, G. Pickavance, J. R. Poulsen, J. M. Reitsma, D. Sheil, M. Simo, K. Steppe, H. E. Taedoumg, J. Talbot, J. R. D. Taplin, D. Taylor, S. C. Thomas, B. Toirambe, H. Verbeeck, J. Vleminckx, L. J. T. White, S. Willcock, H. Woell and L. Zemagho
Research Interests: Art and Rainforest
The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015–2016 El Niño Southern Oscillation resulted in unprecedented heat and... more
The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015–2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once...
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Abstract Forests provide many resources, ecosystem services and absorb carbon dioxide, which helps in climate regulation. In spite of the enormous benefits of forests, the issue of deforestation is still ongoing. There has been a... more
Abstract Forests provide many resources, ecosystem services and absorb carbon dioxide, which helps in climate regulation. In spite of the enormous benefits of forests, the issue of deforestation is still ongoing. There has been a continuous decline in forests globally and the forest area of Boabeng Fiema Monkey Sanctuary (BFMS) in Ghana is facing a similar threat. The aim of the study is to determine the different forest cover types and changes in the forest of BFMS. Satellite images for the years 1992, 1998, 2004, 2010, 2016 and 2018 were downloaded. Unsupervised and supervised classification were performed to determine the different forest cover types and remote sensing software was used to detect the changes in the forest cover. The forest cover was classified into six classes; closed forest, open forest, savannah woodland, savannah, farmlands and built-up area. Available data suggests that between 1992 and 2018, closed forest decreased by 242.19ha, open forest increased by 122.85 ha, savannah woodland increased by 7.47ha, savannah increased by 6.48 ha, farmland increased by 39.39ha and built-up area increased by 65.7ha. The changes in closed forest, open forest, farmland and built-up were all significant. Decreasing forest cover of BFMS is a threat to sustainable ecotourism since the forest serves as a habitat and food source to the monkeys. This research serves as guide to other researches aiming at determining forest cover changes in forest-savannah transition zones. In addition, the results have produced an inventory of the forest, which will help forest resource managers sustainably manage the forest.
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ABSTRACT Background: Forest and savanna vegetation in the zone of transition (ZOT) contain distinct woody species due to fire, drought and herbivory barriers that constrain forest species from invading adjacent savannas and vice-versa.... more
ABSTRACT Background: Forest and savanna vegetation in the zone of transition (ZOT) contain distinct woody species due to fire, drought and herbivory barriers that constrain forest species from invading adjacent savannas and vice-versa. Little is known if these barriers cause divergence in species composition between the overstorey and understorey strata in these vegetation types. Aim: We investigated woody species composition across overstorey and understorey strata in the ZOT and explored the relationship between soil fertility and species composition patterns. Methods: We sampled overstorey and understorey woody species and determined soil nutrient concentrations in twenty-five 20 m × 20 m plots in a ZOT in Ghana. Results: Forest and savanna species dominated the overstorey and understorey of their respective environments. However, species composition was decoupled between the overstorey and understorey strata in both forest and savanna vegetations. Few savanna and forest species had individuals co-occurring in both overstorey and understorey such that ~65% of the dominant species was limited to only one stratum. Soil fertility had little effect on these patterns. Conclusion: These patterns indicate that, forest and savanna species face significant recruitment barriers in their respective environments, suggesting that requirements for juvenile establishment may differ from recruitments to the canopy layer.
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Research Interests: Biology and Monoculture
References Brown, S., Pearson, T., Moore, N., Parveen, A., Ambagis, S., Shoch, D., 2005. Impact of selective logging on the carbon stocks of tropical forests:Republic of Congo as a case study. Winrock International. DeFries, R., Achard,... more
References Brown, S., Pearson, T., Moore, N., Parveen, A., Ambagis, S., Shoch, D., 2005. Impact of selective logging on the carbon stocks of tropical forests:Republic of Congo as a case study. Winrock International. DeFries, R., Achard, F., 2002. New estimates of tropical ...