A quantitative assessment of forest rejuvenation activities in a community at the borders of Hwange National Park using GIS and Remote Sensing

Abstract

Various natural and human activities lead to land degradation in the Hwange National Park and in the surrounding communal areas. The deforestation in turn upsets the natural ecosystem and reduced vegetation leads to reduced soil moisture holding capacity, and reduced carbon sequestration of the forest and the subsequent loss of biodiversity. Attempts to rejuvenate the forest through activities that include holistic grazing methods, swales, mulching fields, cover crops, gabions, erosion repair and the manufacturing of rocket stoves to minimise the reliance of inhabitants on firewood have barely been followed up by a scientific methodology to assess the effectiveness of the various methods used. The impacts of these rejuvenation activities were studied over a period of five years (2017-2022) using the Normalized Difference Vegetation Index (NDVI) and land cover changes. Yearly mean NDVI values were computed to reduce the bias on changes in leaf phenology caused by differences in rainfall. Results show an increase of NDVI from a mean of 0.304 in 2020 to a mean of 0.345 in 2021.  More so a 30% increase in 2021 and 46% increase in 2022 from the previous year’s respectively for forest cover in the study area. The results show the positive impact of the rejuvenation activities being done.