Variabilidade quantitativa de população microbiana associada às condições microclimáticas observadas em solo de floresta tropical úmida

Abstract

This study is a proposal for a scientific contribution to the understanding of the interrelationships between density population of soil microorganisms associated with seasonal microclimatic variability in tropical rainforest, also considering a case study of extreme event. Some organisms, especially soil microorganisms are very sensitive to small variations in microclimate (sun light, temperature, soil moisture, wind, sensible heat, latent heat, etc). Surely these conditioning factors are important for understanding the spatial distribution of these living things in natural ecosystems, inhabited by a variety of microorganisms (mushroom and bacteria) that were studied for their distribution and density, using the technique of "Pour Plate" count of "Petri plates" following the methodology utilized for De-Polli and Guerra, described by Clark. This study was conducted in two experimental areas PPBio (natural rainforest area) and ESECAFLOR (one acre covered area to simulate drought) in Caxiuanã-PA, with continuous measurements of microclimatic variables such as temperature, humidity and rainfall, and the evaluation of spatial and temporal distribution patterns of the species abundance and richness, to establish a monitoring procedure of soil fungi and bacteria associated with climate variability in the national forest Caxiuanã. The experimental areas are predominantly Yellow Latossol soils. Microbiological analysis showed that fungi developed better during the dry season and bacteria during rainy season, and their populations decrease with depth, except in a changed environment. Correlation values between seasonal variation of fungi and bacteria population and varying temperature and soil humidity were satisfactorily for any season in both sites.