Forest Cover and Ecosystem Service Change: Assessing Household Economic Vulnerability to Drought Shocks in the Central Districts of Uganda

Natural forests in Uganda have experienced both spatial and temporal modifications from different
drivers which need to be monitored to assess the impacts of such changes on ecosystems and
prevent related risks of reduction in ecosystem service benefits. Ground investigations may be
complex because of dual ownership, whereas remote sensing techniques and GIS application enable
a fast multi-temporal detection of changes in forest cover and offer a cost-effective option for
inaccessible areas and their use to detect ecosystem service change. The overarching goal of this
study was to use satellite measurements to study forest change and link it to ecosystem service
benefit reduction (fresh water) in the study area using a representative sample of Landsat scenes,
also assessing the influence of forest cover loss on drought prevalence using soil moisture content
time series satellite data. In addition to assessing household economic vulnerability to drought in the
central districts of rural Uganda. In this paper, an integrated approach of remotely derived indices was
used together with post-classification comparison to detect forest cover and ecosystem service
change. In addition the study used satellite time series data of soil moisture content to assess drought
prevalence and household vulnerability to drought shocks. Our contribution novelty is the ability to
detect at multi-temporal scale private and central reserve forest cover decline along with ecosystem
benefit reduction using remotely derived indices in the 20 year period (1986-2005). Change detection
analysis showed that forest cover declined significantly in five sub-counties of Mpigi, than in
Butambala by 5.99%, disturbed forest was 3%, farm land increased by 44%, grassland declined by
62.5% and light vegetation increased by 63.6%. The two most affected areas also experienced fresh
water reductions. The two drought indices of SPI and SWDI confirmed existence of drought shocks
causing vulnerability of household to food insecurity and uncertainty in welfare levels. For sustainable
supply of ecosystem service benefits and maintenance of standard welfare, resource managers
especially natural forests must also involve private resource owners in the conservation effort.