Document type
Academic documents
Document subtype
Master's dissertation
Title
Efeito do tipo de solo e regime de fogo no microbiota do solo e na resposta fisiológica de duas espécies prioritárias de Miombo: Brachystegia spiciformis Benth e Brachystegia boehmii Taub. no Parque Nacional da Gorongosa
Participants in the publication
Camilo B. (Author)
Máguas C. (Co-Supervisor)
Dep. Biologia Vegetal
cE3c
Ribeiro-Barros A. (Co-Supervisor)
INSTITUTO SUPERIOR DE AGRONOMIA
Maquia I. (Co-Supervisor)
UNIVERSIDADE EDUARDO MONDLANE
Summary
Miombo woodland is Mozambique's largest ecosystem, considered to be the most bio-diverse ecoregion in southern Africa. This ecosystem consists of dry savannah adapted to severe climate conditions with high temperatures, low rainfall and low nutrient availability, and has irreplaceable environmental and socioeconomic value, playing key roles in the energy, water and carbon balance, and contributing to formal and informal economies in urban and rural communities. However, its structure has been threatened by climate change, human and animal pressure, which collectively impose high frequencies and intensities of fire, which in the medium and long term can reduce species abundance and compromise ecosystem functioning. Soil microbiome (sequencing of 16S rDNA ribosomal gene) and stable isotope ecology (δ15N, δ13C and C/N) were characterized in two typical species of the miombo ecosystem, Brachystegia boehmii and Brachystegia spiciformis in two soil types (sandy and loamy) and subject to two fire regimes (high and low frequency). The species under study are tree legumes with an important nitrogen-fixing function, found in one of Africa's most valuable conservation areas and one of the largest repositories of biodiversity globally, Gorongosa National Park. According to microbiome analysis, microbial diversity is high, regardless of species, soil type and fire regime. The dominant phyla were Actinobacteria, Acidobacteria and Proteobacteria, possessing a wide range of ecological functions, such as nitrogen fixators, decomposition of recalcitrant soil matter and plant growth promoters. The relationships of δ15N, δ13C and C/N varied according to soil type, fire frequency and species, in which the clay soil and low fire frequency presented more enriched values of δ15N e δ13C, and B. boehmii showed depleted values of δ15Ne δ13C compared to B. spiciformis. In ecological terms B. boehmii tends to fix nitrogen from the soil. The study indicates a strong relationship between fire regime and soil type, ie higher levels of biodiversity and abundance in B. boehmii (loamy soil and low frequency of fire), either isotope (δ15N and δ13C). showed adequate species discrimination potential, confirming its usefulness for photosynthetic studies.
Institution
Consórcio de BioEducação do Chitengo
Publication Identifiers
Keywords
Microbiome
Rhizosphere
Metagenomic
Carbon
Nitrogen
Stable isotopes