An Analysis of the Influence of Annual Rainfall Fluctuations on Wildfire Occurrence in Protected Areas in the Northwest of Zimbabwe

Abstract

The occurrence and threat from wildfires are a conservation concern in semi-arid savanna-protected areas. The risk of wildlife occurrence is uncertain under climate change scenarios. However, general predictions are that different changes are likely to occur in weather conditions in different landscapes. We sought to analyze the influence of annual precipitation on wildfire occurrence in a protected area landscape in northwest Zimbabwe. Data on annual rainfall received and wildfire occurrence for Chizarira National Park (CNP), Chirisa Safari Area (CSA), and Sengwa Wildlife Research Area (SWRA) was analyzed using regression analysis. The relationship between the annual precipitation amount received per site and the number of wildfires recorded per site showed a positive correlation only for CSA. No significant differences were observed for CNP and SWRA at a significant level of p< 0.05. The highest number of wildfires were recorded between July and November. We advance that annual rainfall is one factor among many drivers of wildfires and that this is not uniform but varies across the landscape. Effective annual precipitation contributes to high vegetation biomass production and accumulation of such biomass increases the risk of wildfires. In some instances, rainfall patterns could not explain the occurrence of wildfires. We, therefore, contend that other drivers such as human activities and natural factors are important drivers of wildfires across the three sites. The conservation implication of our finding is that robust fire management plans need to take an ecosystem approach that includes communities adjacent to protected areas.