Study On The Mechanisms Between Land Use Change And Ecosystem Service Valuation Of Ghana, West Africa

Changes in land use have a significant effect on the environment by disrupting natural landscape patterns.These changes may alter ecological processes,which affect the flow and provision of ecosystem services.In this study,we quantified land use change and the effect of landscape patterns on estimated ecosystem service values(ESV)on spatial and temporal scales in Ghana for three different years;1995,2005 and 2015.Using Fragstats spatial software,we were able to compute landscape metrics to calculate the landscape patterns of the study area.We established the relationship between ecosystem service and landscape patterns with the use of correlation and regression analysis.The dominant land use in Ghana found in decreasing order was agriculture,forest and savannah respectively.The portions covered with the settlement and bare land were relatively small.The estimated ESV for the study periods were US$ 161.64 billion in 1995,US$ 150.91 billion in 2005 and US$ 150.02 billion in 2015.The ESV declined rapidly within 1995-2005 but steadily declined from 2005-2015.Moreover,the entire decline observed for the period was very significant(US$ 11.62 billion),and this was because of the huge reduction in wetland area during the period.At the regional administrative level,the Northern Region was the highest contributor to the national ESV estimated with US$41.77 billion in the current study year.The Brong Ahafo Region was the next highest contributor and the least contributor to the national ESV was Greater Accra Region with 2.39 in 2015.Linear multiple regression and correlation analysis revealed the relationships between ecosystem services and landscape patterns.From the regression models,different individual landscape metrics of landscape composition and configuration combined to have a net effect on the individual ecosystem services.Again,the effects of land use change on landscape patterns using ten landscape-level and eight class-level landscape pattern metrics revealed increased fragmentation and reduced diversity of the various land use classes.Increase in settlement areas increased in patch number and density which indicted the spread of random clusters of settlements in urban areas.With respect to the relationship between topography and ecosystem services,elevation and slope showed significant negative relationship with ESV while that of aspect and ESV was not significant.Furthermore,elevation and slope negatively correlated with all the individual ESV.On the other hand,aspect correlated significantly with nine of the individual ESV.This study provides useful reference material for land use policymakers,managers and institutions involved in the implementation of policies and conservation practices to enhance the provision of ecosystem services.