Effect of Castanea sativa plantation age on soil bacterial communities

Soil microbial communities are involved in key processes of forest ecosystems that include decomposition of organic matter, cycling of nutrients or formation of structure. The composition and diversity of these communities depend on a large number of factors such as humidity, pH, nutrient levels, C content, or the type of vegetation cover. Despite the high forest area of the Iberian Peninsula, the bacterial communities of these soils are still poorly studied and characterized. This work is carried out in the interior of the region of Galicia (NO of the Spain) where the main plantations of Castanea sativa are found in this region. The objective of this work was to study the effect of the plantation age on the microbial communities that develop in these soils. For this, soil samples were taken in plantations of two different ages: young plantations (10-15 years) and centennial plantations. Soil samples were collected at 50 cm and the different visually identifiable horizons were separated. The bacterial communities present in the organic horizon were characterized by massive sequencing of the 16SrDNA ribosomal gene. The results will be discussed in terms of bacterial diversity, composition and functionality (focusing on bacterial groups potentially involved in N or C cycling).