Greenspace Spatial Characteristics and Human Health in an Urban Environment at Osogbo, Nigeria

Abstract

Background/Aim: Urbanization amongst other anthropogenic factors is a major cause of unprecedented loss of urban forest and green spaces over time. The changes in urban forest pattern has affected biodiversity, urban-ecology, human health, quality of life and urban sustainability, therefore, this study examined the spatial characteristics and human health as indicator of improved residential environment in Osogbo, Nigeria. Methods: Semi-structured questionnaire were randomly administered to 405 residents to elicit information on urban forest services and management. Changes in vegetation cover was examined by the Normalized Difference Vegetation Index (NDVI) and Land Use Land Cover (LULC) change of the study area was derived from Landsat imageries of 1987, 1997, 2007 and 2017. These spatial metrics were computed using FRAGSTAT interfaced with ArcGIS to explain the landscape dynamics of the area. The data obtained from the administered questionnaire were subjected to descriptive statistical tools. Results: The LULC analysis revealed that 2017 had the highest amount of built up area (7.26 km2) compared to 1987 when built up area was 56.29 km2. Dense vegetation was highest in 1987 (113.40 km2) when compared to 2017 (53.80 km2). NDVI value for 1987 was highest (-0.206 - 0.418) due to presence of dense vegetation while the value for 2017 (-0.009 - 0.299) indicated loss of vegetation. The number of patches decreases from 66.31 Km2 in 1987 to 22.24 Km2 in 2017. These values indicate that the health status was lower in 1987 than in 2017. The residents strongly agreed that forest trees could provide products and services (92.8%), protect against environment hazards (87.4%) and improve health and wellbeing of humans (89.6%). Conclusion: The study concluded that urbanization had negative effects on the health state of the environment.