Stephen Kankam

Mr. Stephen Kankam


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
13 May 2021 in Sensors
Verified
Journal Article
Open access
PDF file
Alex Owusu AmoakohAlex Owusu Amoakoh
Alex Owusu Amoakoh
Paul AplinPaul Aplin
Paul Aplin
KAKwame Awuah
Kwame Awuah
IDIrene Delgado-Fernandez
Irene Delgado-Fernandez
CMCherith Moses
Cherith Moses
JMJustice C. Mensah
Justice C. Mensah
Tropical peatlands such as Ghana’s Greater Amanzule peatland are highly valuable ecosystems and under great pressure from anthropogenic land use activities. Accurate measurement of their occurrence and extent is required to facilitate sustainable management. A key challenge, however, is the high cloud cover in the tropics that limits optical remote sensing data acquisition. In this work we combine optical imagery with radar and elevation data to optimise land cover classification for the Greater Amanzule tropical peatland. Sentinel-2, Sentinel-1 and Shuttle Radar Topography Mission (SRTM) imagery were acquired and integrated to drive a machine learning land cover classification using a random forest classifier. Recursive feature elimination was used to optimize high-dimensional and correlated feature space and determine the optimal features for the classification. Six datasets were compared, comprising different combinations of optical, radar and elevation features. Results showed that the best overall accuracy (OA) was found for the integrated Sentinel-2, Sentinel-1 and SRTM dataset (S2+S1+DEM), significantly outperforming all the other classifications with an OA of 94%. Assessment of the sensitivity of land cover classes to image features indicated that elevation and the original Sentinel-1 bands contributed the most to separating tropical peatlands from other land cover types. The integration of more features and the removal of redundant features systematically increased classification accuracy. We estimate Ghana’s Greater Amanzule peatland covers 60,187 ha. Our proposed methodological framework contributes a robust workflow for accurate and detailed landscape-scale monitoring of tropical peatlands, while our findings provide timely information critical for the sustainable management of the Greater Amanzule peatland.

8 September 2021 in Socio-Ecological Practice Research
Verified
Journal Article
Open access
PDF file
SKStephen Kankam
Stephen Kankam
JIJustice Nana Inkoom
Justice Nana Inkoom
HKHongmi Koo
Hongmi Koo
CFChristine Fürst
Christine Fürst
Cultural ecosystem services (CES) in Southwestern Ghana evoke a strong sense of attachment of local land users to the landscape. Hence, their supply is necessary for a balanced socio-ecological system. This study explored the potential supply of cultural ecosystem services (science/education, spiritual, tourism, health and recreation benefits) under different land use planning (LUP) scenarios in Southwestern Ghana. Future LUP scenarios were developed and articulated with a diverse group of land-use planning actors (LUPAs) such as regional land use planners, environmental experts, researchers, farmers and landowners. The scenarios covered business-as-usual, mangrove ecosystem restoration, market-driven growth, and the establishment of an “eco-corridor” as green network. A spatially explicit modeling platform, GISCAME, which combines Geographic Information System and Cellular Automaton modules and multicriteria evaluation was used to evaluate the developed scenarios. Outcomes of the study revealed that in the coastal landscape of Southwestern Ghana, values, perceptions and preferences of LUPAs underpin socio-ecological interactions aimed at maintaining and enhancing CES supply. In addition, it indicated that future supply of CES is characterized by an interplay between multiple and diverse perspectives about plausible land-use futures. Perceptions of, and preferences for, CES align with land-use visions related to afforestation, infrastructure development, agriculture expansion and tourism. In the study area and similar contexts where an array and diversity of individual and societal values exist, effective negotiation and facilitation are essential for harnessing and optimizing land-use planning for CES supply.

29 October 2024 in Remote Sensing
Verified
Journal Article
Open access
PDF file
Alex Owusu AmoakohAlex Owusu Amoakoh
Alex Owusu Amoakoh
Paul AplinPaul Aplin
Paul Aplin
Pedro Rodríguez VeigaPedro Rodríguez Veiga
Pedro Rodríguez Veiga
CMCherith Moses
Cherith Moses
CACarolina Peña Alonso
Carolina Peña Alonso
DNDaniel Doku Nii Nortey
Daniel Doku Nii Nortey
The Greater Amanzule Peatlands (GAP) in Ghana is an important biodiversity hotspot facing increasing pressure from anthropogenic land-use activities driven by rapid agricultural plantation expansion, urbanisation, and the burgeoning oil and gas industry. Accurate measurement of how these pressures alter land cover over time, along with the projection of future changes, is crucial for sustainable management. This study aims to analyse these changes from 2010 to 2020 and predict future scenarios up to 2040 using multi-source remote sensing and machine learning techniques. Optical, radar, and topographical remote sensing data from Landsat-7, Landsat-8, ALOS/PALSAR, and Shuttle Radar Topography Mission derived digital elevation models (DEMs) were integrated to perform land cover change analysis using Random Forest (RF), while Cellular Automata Artificial Neural Networks (CA-ANNs) were employed for predictive modelling. The classification model achieved overall accuracies of 93% in 2010 and 94% in both 2015 and 2020, with weighted F1 scores of 80.0%, 75.8%, and 75.7%, respectively. Validation of the predictive model yielded a Kappa value of 0.70, with an overall accuracy rate of 80%, ensuring reliable spatial predictions of future land cover dynamics. Findings reveal a 12% expansion in peatland cover, equivalent to approximately 6570 ± 308.59 hectares, despite declines in specific peatland types. Concurrently, anthropogenic land uses have increased, evidenced by an 85% rise in rubber plantations (from 30,530 ± 110.96 hectares to 56,617 ± 220.90 hectares) and a 6% reduction in natural forest cover (5965 ± 353.72 hectares). Sparse vegetation, including smallholder farms, decreased by 35% from 45,064 ± 163.79 hectares to 29,424 ± 114.81 hectares. Projections for 2030 and 2040 indicate minimal changes based on current trends; however, they do not consider potential impacts from climate change, large-scale development projects, and demographic shifts, necessitating cautious interpretation. The results highlight areas of stability and vulnerability within the understudied GAP region, offering critical insights for developing targeted conservation strategies. Additionally, the methodological framework, which combines optical, radar, and topographical data with machine learning, provides a robust approach for accurate and detailed landscape-scale monitoring of tropical peatlands that is applicable to other regions facing similar environmental challenges.

25 February 2021 in Socio-Ecological Practice Research
Verified
Journal Article
Closed access
PDF file
Tom DanielsTom Daniels
Tom Daniels
JCJeffrey K.H. Chan
Jeffrey K.H. Chan
SKStephen Kankam
Stephen Kankam
MMMichael Murphy
Michael Murphy
DDDon Day
Don Day
HKHongmi Koo
Hongmi Koo

27 August 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
Alex Owusu AmoakohAlex Owusu Amoakoh
Alex Owusu Amoakoh
Paul AplinPaul Aplin
Paul Aplin
Pedro Rodríguez VeigaPedro Rodríguez Veiga
Pedro Rodríguez Veiga
CMCherith Moses
Cherith Moses
CACarolina Peña Alonso
Carolina Peña Alonso
DNDaniel Doku Nii Nortey
Daniel Doku Nii Nortey
The Greater Amanzule Peatland (GAP) in Ghana represents an important ecosystem facing dynamic land cover changes as a result of both natural and anthropogenic factors. This study integrates multispectral and radar remote sensing data from Landsat-7 and -8, L-band SAR, and SRTM to conduct a machine learning-based analysis of these changes from 2010 to 2020 and to predict future scenarios up to 2040. Findings reveal a 12% expansion in peatland cover, equivalent to approximately 6,570 ± 308.59 hectares, despite declines in specific peatland types. Concurrently, anthropogenic land uses have increased, evidenced by an 85% rise in rubber plantations (from 30,530 ± 110.96 hectares to 56,617 ± 220.90 hectares) and a 6% reduction in natural forest cover (5,965 ± 353.72 hectares). Sparse vegetation, including smallholder farms, decreased by 35% from 45,064 ± 163.79 hectares to 29,424 ± 114.81 hectares. Projections for 2030 and 2040 indicate minimal changes based on current trends; however, these do not consider potential impacts from climate change, large-scale development projects, and demographic shifts, necessitating cautious interpretation. The results highlight areas of stability and vulnerability within the GAP and offer critical insights for the development of targeted conservation strategies. Additionally, the methodological framework presented provides a robust approach for accurate and detailed landscape-scale monitoring of tropical peatlands, applicable to other regions facing similar environmental challenges.