Detection of potentially gas flaring related pollution on vegetation cover and its health using remotely sensed data in the Niger delta, Nigeria
Barnabas O Morakinyo
Department of Surveying & Geoinformatics, Faculty of Environmental Sciences, BAZE University, Abuja, Nigeria, and School of Marine Science & Engineering, Faculty of Science & Technology, University of Plymouth, Pixalytics Ltd, ARGANS Ltd, Plymouth, UK.
https://orcid.org/0000-0002-5066-8071
Samantha Lavender
School of Marine Science & Engineering, Faculty of Science & Technology, University of Plymouth, and Pixalytics Ltd, Plymouth, UK.
https://orcid.org/0000-0002-5181-9425
Victor Abbott
School of Marine Science & Engineering, Faculty of Science & Technology, University of Plymouth, Plymouth, UK.
https://orcid.org/0000-0003-3972-3102
DOI: https://doi.org/10.20448/arees.v10i1.4407
Keywords: Detection, Landsat 7, Landsat 8, Niger delta, Pollution, Remotely sensed data, Vegetation cover.
Abstract
Detection of potentially gas flaring-related pollution on vegetation cover using remotely sensed data at 11 flaring sites in Rivers State, Nigeria is the emphasis of this research. 21 Landsat 7 Enhanced Thematic Mapper Plus (ETM ), and 4 Landsat 8 Operational Land Imager and Thermal Infrared Sensor (OLI-TIRS) data dated from 21/04/2000 to 05/02/2022 with 3 cloud cover were used. Normalized Differential Vegetation Index (NDVI) was retrieved from corrected Landsat 7 bands (1-4), and Landsat 8 bands (2-5). Corrected thermal band was used for the computation of Land Surface Temperature (LST). Change in NDVI (δNDVI450-60)m and LST ( δLST60-450m) were computed. NDVI values at 60 m from the stack show that as the year increases, NDVI values around the stack reduces to almost zero. Linear regression analysis was considered for (δ NDVI450-60)mN against ( δNDVI450-60)mE, (δNDVI450-60)mN against (δNDVI450-60)mS, and (δNDVI450-60)mN against (δNDVI450-60)mW. Only (δNDVI450-60)mN against (δNDVI450-60)mW give statistically significant results at 99 % confidence level (p-value 0.0016). (δNDVI450-60)mN,E,S,W against (δLST60-450)mN,E,S,W were considered and results show positive correlation but statistically insignificant. Based on the results of this research, it can be concluded that flaring-related pollution can be detected on vegetation cover using Landsat 7 and Landsat 8 data in the Niger Delta.