Evaluation of three classifiers in mapping forest stand types using medium resolution imagery: a case study in the Offinso Forest District, Ghana

Loss of Ghana’s natural forests has been counteracted by plantation establishment and development. As at 2003, Ghana had a plantation area of about 97,000 hectares comprising different tree species. With the rapid expansion of plantations in the country, it is anticipated that major managerial challenges will arise due to insignificant technical personnel for monitoring and management. The application of GIS and remote sensing will be a powerful intervention and tool for monitoring and managing these forest resources in the area. The aim of this study was to determine a suitable method of mapping the different forest stand types using medium resolution images in the study area. Three classifiers were examined for their suitability in mapping the different forest stand types in the area (maximum likelihood, spectral angle mapper and decision tree). The results showed that using maximum likelihood classifier and ASTER imagery, different forest stand types can be accurately mapped with an overall accuracy of 88.50%.Key words: Geo-referenced, classification, algorithm, spectral, mapper

Farmers Awareness and Response to Climate Change: A Case Study of the North Bank Region, The Gambia

Rain-fed agriculture, which is the backbone of most sub-Saharan economies is seriously under threat due to climate change. Consequently, for farmers to sustain their livelihoods and increase productivity, there is the need for them to be aware of climate change and how they can sustainably respond to it. This study focused on farmers’ awareness of climate change and their response to its effect in the North Bank Region of The Gambia. Data for the study was collected from 258 farmer household heads selected through a multi-stage sampling technique and 9 focus group discussions. Descriptive statistics and climate change awareness index (CCAI) were used to analyze the data obtained from the households. The findings revealed that majority (80.6%) of the farmers were aware of climate change with an average awareness index of 0.586 (58.6%). Also, an overwhelming majority of 93.41% of the farmers used crop diversifications, drought resistant cultivars, early maturing varieties among others as response strategy to climate change. The study concludes that farmers in the study area are fairly aware of climate change. Farmers are recommended to form farmer associations to enable easy access to more climate change education/ training from Donor and Government agencies to improve their climate change knowledge and enhance their adaptive capacity. Keywords: Climate change, Response, Climate change Awareness Index, The Gambi

Estimating the Extent of Degradation in the Bounfum Forest Reserve, Ghana, Using Historical Remotely Sensed Data and Landscape Fragmentation Indices

Land use and land cover changes, especially deforestation and forest degradation and its driving factors, are key factors hindering sustainable forest management. Currently, there is limited knowledge concerning the detection of the extent and interpretation of the spatial and temporal pattern of forest cover dynamics in the Bounfum Forest Reserve, which when available will inform sustainable policies. Using the Landsat TM image of 1986, Landsat ETM+ image of 2002 and Landsat 8 OLI image of 2014, the study identified and quantified the forest cover dynamics in the Bounfum Forest Reserve from 1986 to 2014. The ERDAS maximum likelihood classification algorithm was used to classify the pixels into five major land cover classes namely, bare/built areas, farmlands, closed forest, open forest and shrub/grassland. The Kappa coefficients of 0.83 (1986), 0.72 (2002) and 0.75 (2014) respectively were obtained for the classified images. The findings showed that the closed forests decreased by 3.5% (563.90 ha) per annum whilst the open forests and farm lands increased by 19.5% (385.60 ha) and 2.9% (65.00 ha) per annum within the 28-year period. This implies that the Bounfum forest reserve has been highly degraded over the past 28 years, evident through the trends of its patch densities and the number of patches. Collaborative forest management is required in the management of the forest reserve to conserve the socio-ecological and economic benefits derived from the resource on sustainable basis. Keywords: Land use and land cover change, Bounfum forest reserve, deforestation, forest degradation, remote sensing, sustainable forest managemen

Simulation of Land Use/Cover Dynamics Using the CA-Markov Chain Model in the Yayo Coffee Forest Biosphere Reserve, Southwestern Ethiopia

Successful implementation of natural resource planning and land management systems requires understanding of how land use and land cover (LULC) have changed in the past and how they will change in the future, taking into account both space and time. The Yayo Coffee Forest Biosphere Reserve (YCFBR), in southwestern Ethiopia, is currently experiencing the consequences of different human actions such as wildfires and the expansion of coffee plantations. Although the Biosphere Reserve (BR) has undergone significant changes and efforts since it was registered by UNESCO in 2010, there is still a lack of information regarding the future trends of LULC change. The primary aim of the study is to simulate the potential changes in LULC in the YCFBR area for the upcoming three decades. In this study, we utilized Landsat satellite imagery taken in 1992, 2007, and 2022 for analysis. The findings suggest that the agricultural area is expected to grow from 20.3% in 2022 to 24% in 2052, while the proportion of open forest is predicted to rise from 13.4% in 2022 to 18% in 2052. In addition, there is an anticipated decrease in both high forest and grazing lands. High forest is expected to decline from 50.1% in 2022 to 40% in 2052, while grazing lands are projected to decrease from 8.3% in 2022 to 6% in 2052. The study period anticipates significant shifts from grazing land to agriculture and from high forest to more open forest areas. This research offers valuable insights to help planners and decision-makers to effectively plan for future conservation efforts by understanding the historical, current, and future patterns of LULC dynamics

Potential impact of future land use/cover dynamics on the habitat quality of the Yayo Coffee Forest Biosphere Reserve, southwestern Ethiopia

AbstractHuman activities, including agricultural expansion, urbanization, and industrial advancement, have led to land use/cover change (LULCC). These changes have had negative consequences, such as the loss of species and the degradation of forest areas. The Yayo Coffee Forest Biosphere Reserve (YCFBR) is undergoing changes due to forest fires and encroachment from coffee plantations, which are predicted to increase in the future. The objective of this study was to simulate the dynamics of LULCC and its impact on habitat quality in the area over the next three decades. The study used classified land cover (LC) maps of 1992, 2022, and 2052 (predicted), as well as factor and constraint maps of the area. In addition, household surveys, key informant interviews (KII), and focus group discussions (FGD) were conducted to understand the factors influencing changes in habitat quality. Habitat quality was simulated under three different future scenarios (Business as Usual; S1), conservation scenario (S2), and development scenario (S3) using CA-Markov, Future Land Use Simulation (FLUS), and Integrated Valuation of Environmental Services Tradeoffs (InVEST) models. The result showed a 28% increase in open forest and a 35% increase in agricultural area under S1, with a minimal increase in built-up area. The medium-level habitat quality increased from 11.3% in 1992 to 27.8% in 2052 S3. The highest average haitat quality value was 0.62 in S2, while the lowest was 0.51 in S3. If S3 is the case, this value is expected to fall below 40%, indicating the lowest possible level of habitat quality in the future. The model also predicts a 7% increase in high forest areas in S2, indicating the possibility of an alternative path to save high forest loss in the area. The main causes of habitat quality deterioration include population growth, agricultural land expansion, a lack of diverse incomes, land tenure issues, and settlement expansion. Based on the findings, S2 appears to be the best future scenario for maintaining habitat quality. This study provides useful information that will help planners and decision-makers effectively prepare future conservation strategies

Livelihood implications of artisanal gold mining in farming communities: insight from the Wa East District, Ghana

The impact of artisanal mining on livelihoods in developing countries is a contentious issue. As a contribution to this subject, the study assessed the implications of artisanal gold mining activities on smallholder agriculture in the Wa East District of Ghana. A descriptive survey design with a mixed methods research approach was used. Primary data were sourced from respondents through interviews, questionnaire administration, and field observation. Five artisanal mining communities were selected based on the intensity of mining activities in them. The study respondents consisted of 290 household heads drawn randomly from 1,050 households. Also, key informants consisting of 5 assembly members and 15 lead artisanal miners were interviewed. The study found artisanal mining to be a dominant livelihood strategy in the district, employing about 76.2% of respondents at various levels. Artisanal mining contribution to household income was higher than food crop farming. Proceeds from mining are used to finance smallholder agriculture. However, the activities of the miners have resulted in the degradation of farmlands. We argued that artisanal mining activities should be aligned with other livelihood options such as agriculture in local communities. The study called for the engagement of local miners and traditional rulers in mineral resource decision-making

Seasonal changes in pasture biomass and grazing behaviour of cattle in the Guinea Savanna agroecological zone of Ghana

Spatial and temporal availability of pasture vegetation and cattle grazing behaviour in three seasons (intermediate season [IM], peak season [PS] and dry season [DS]) in the Guinea Savanna agroecological zone of Ghana was examined. The frequency of occurrence of three species groups (grass, legume and forbs) and biomass yield was estimated in 1 m² plots. The grazing behaviour of 18 cows from six herds was monitored over three days per animal. Season affected the prevalence of species groups with grasses being most dominant in all seasons. Most grazing lands were heavily grazed in IM and DS but moderately grazed in PS. Whilst harvested rice fields represented the most frequently grazed land in DS, fallowed hard pans were used in PS and IM. Biomass yield was highest in DS owing to the contribution of crop residues from harvested farmlands. Carrying capacity was linked to biomass production and averaged 0.55 in DS, 0.38 in PR and 0.21 in IM. Animals spent less time outside the kraal in PS than IM and DS. Walking time was higher in DS than in IM and PS. Less than 20% of the time on pasture was spent on resting, watering and social interaction across seasons.Keywords: carrying capacity, grazing behaviour, rangeland, savanna, tropical livestock uni

Patterns of green space change and fragmentation in a rapidly expanding city of northern Ghana, West Africa

Green spaces such as forests, grasslands, and croplands (including gardens) can be found in urban environments. Although they benefit human and animal well-being, they have become threatened due to rapid urban growth and unplanned development. Yet, little attention has been given to studying the dynamics of urban green spaces in sub-Saharan Africa. In this study, we examined the dynamics of land use and land cover (LULC) change and fragmentation (especially, green spaces) within the second fastest urbanising city in Ghana, Tamale. In particular, we focused our analyses on its urban core (∼5 km radius around the city centre) due to its relevance to urban economy and society. Landsat data was used to estimate fragmentation metrics of past and future LULC changes in the study area from 1990 to 2052. We found clear patterns of green space decline and fragmentation within the urban core: i.e., green spaces became patchy over time and the pattern was expected to continue in the future. Additionally, we found the built-up class benefited from the decline of green spaces with the latter being significantly negatively correlated with human population size. Our investigation reveals that protected forests and tree plantations contributed to a significant proportion of available green spaces in the urban core. However, these areas were becoming increasingly threatened by forest reserve downsizing, indiscriminate activities (e.g., logging and encroachment), and sale of public lands to private developers, practices commonly associated with population growth. Hence, the enforcement of relevant local legislations (e.g., the 2016 Land Use and Spatial Planning Act [Act 925]) coupled with the integration of urban initiatives and policies that encourage green spaces are needed to ensure the sustainability of urban ecosystems for the well-being of humans and the environment