Tree canopy enhances Collembola functional richness and diversity across typical habitats of the Gorongosa National Park (Mozambique)

Abstract

The role of tree canopies in protecting soil functional diversity is essential for ecosystems threatened by the longer lasting periods of drought, which are predicted to increase in the southern afro-tropical region. Nonetheless, biodiversity inventories of soil mesofauna are scarce in afro-tropical ecosystems, even in emblematic and well-studied protected areas, such as the Gorongosa National Park (GNP). Understanding the interrelationships between tree canopies and soil fauna functional diversity can provide insightful information for future adaptive management to protect wildlife and ecosystem services in the GNP, in the context of climate change. Here we assessed collembolan functional type richness and functional diversity in the dry period and during the rainfall across major GNP habitat types: miombo forests, mixed forests, and open savanna/floodplains. Besides the significant positive influence of rainfall, habitat types also influenced functional type’ richness and diversity of collembolan life-forms. Environmental gradients across habitat types, namely the area of tree canopy cover and its indirect effect on soil local conditions (pH and nutrient availability), explained collembolan functional parameters. Calcium concentrations and soil alkalinity significantly enhanced collembolan functional type richness and functional diversity, respectively. Collembola survival across GNP habitats depended on the canopy buffering in the dry sampling period. These results highlight the key role of tree canopies in creating suitable microhabitat conditions supporting soil functional diversity and the sustainability of soil processes and ecosystem services in GNP.