TY - JOUR
T1 - Ecological risk assessment based on land cover changes
T2 - A case of Zanzibar (Tanzania)
AU - Omar, Hassan
AU - Cabral, Pedro
N1 - info:eu-repo/grantAgreement/FCT/3599-PPCDT/PTDC%2FCTA-AMB%2F28438%2F2017/PT#
Omar, H., & Cabral, P. (2020). Ecological risk assessment based on land cover changes: A case of Zanzibar (Tanzania). Remote Sensing, 12(19), 1-24. [3114]. https://doi.org/10.3390/RS12193114
PY - 2020/10
Y1 - 2020/10
N2 - Land use and land cover (LULC) under improper land management is a major challenge in sub-Saharan Africa and has drastically affected ecological security. Addressing environmental impacts related to this challenge requires efficient planning strategies based on the measured information of land use patterns. This study assessed the ecological risk index (ERI) of Zanzibar based on LULC. A random forest classifier was used to classify three Landsat images of Zanzibar for the years 2003, 2009, and 2018. Then, a land change model was employed to simulate the LULC changes for 2027 under a business-as-usual (BAU), conservation, and extreme scenarios. Results showed that the built-up areas and farmland of Zanzibar Island have increased constantly, while the natural grassland and forest cover have decreased. The forest, agricultural, and grassland were highly fragmented into several small patches. The ERI of Zanzibar Island increased at a constant rate and, if the current trend continues, this index will increase by up to 8.9% in 2027 under an extreme scenario. If a conservation scenario is adopted, the ERI will increase by 4.6% whereas if a BAU policy is followed, this value will increase by 6.2%. This study provides authorities with useful information to understand better the ecological processes and LULC dynamics and prevent unmanaged growth and haphazard development of informal housing and infrastructure.
AB - Land use and land cover (LULC) under improper land management is a major challenge in sub-Saharan Africa and has drastically affected ecological security. Addressing environmental impacts related to this challenge requires efficient planning strategies based on the measured information of land use patterns. This study assessed the ecological risk index (ERI) of Zanzibar based on LULC. A random forest classifier was used to classify three Landsat images of Zanzibar for the years 2003, 2009, and 2018. Then, a land change model was employed to simulate the LULC changes for 2027 under a business-as-usual (BAU), conservation, and extreme scenarios. Results showed that the built-up areas and farmland of Zanzibar Island have increased constantly, while the natural grassland and forest cover have decreased. The forest, agricultural, and grassland were highly fragmented into several small patches. The ERI of Zanzibar Island increased at a constant rate and, if the current trend continues, this index will increase by up to 8.9% in 2027 under an extreme scenario. If a conservation scenario is adopted, the ERI will increase by 4.6% whereas if a BAU policy is followed, this value will increase by 6.2%. This study provides authorities with useful information to understand better the ecological processes and LULC dynamics and prevent unmanaged growth and haphazard development of informal housing and infrastructure.
KW - Ecosystem services
KW - Land change modeling
KW - Landscape ecological statistics
KW - Random forest classifier
UR - http://www.scopus.com/inward/record.url?scp=85092488849&partnerID=8YFLogxK
UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS_CPL&DestLinkType=FullRecord&UT=WOS:000586740600001
U2 - 10.3390/RS12193114
DO - 10.3390/RS12193114
M3 - Article
AN - SCOPUS:85092488849
VL - 12
SP - 1
EP - 24
JO - Remote Sensing
JF - Remote Sensing
SN - 2072-4292
IS - 19
M1 - 3114
ER -