Integrating UAV and satellite data to assess the effects of agroforestry on microclimate in Dodoma region, Tanzania

The present study investigates the microclimatic effect of trees in agroforestry systems in Dodoma region, Tanzania. A pixel-based analysis of Land Surface Temperature (LST) and Tree Canopy Cover (TCC) was performed on aerial imagery obtained with an Unmanned Aerial Vehicle (UAV) and on satellite data. UAV orthomosaic maps and satellite scenes were elaborated with a suite of Geographical Information Systems and the resulting data were statistically analyzed through linear regression, the Kruskall-Wallis test and the Dunn test. Results showed that the TCC of the surveyed areas was 5,1%, and a significant decrease in LST of 1,32 °C (p<0,01) was only found in areas with the highest TCC, during the late dry season. From these preliminary analyses, we suggest that a threshold of 10% TCC should be reached to have an ameliorated microclimate, in terms of temperature, in this agroecological zone. Considering the average plant phenotype characteristic to the area, it corresponds to a tree density of 50 trees per hectare.