Orals

Soil biodiversity and function are highly responsive to natural and anthropogenically inflicted changes. Soil biota are affected by climatic factors (temperature and soil moisture) as well as by the quality of above and belowground litter. Climatic variables affect soil community structure and activity by direct and indirect interactive factors. Directly, via suppression of particular groups by low/high mean annual temperatures or by drought/flooding, and indirectly, via regulation of plant community composition and productivity. Plant communities determine structure and activity of microorganisms by chemical composition of litter and root exudates (nutrients), as well as modifying soil chemical properties (pH, soil organic matter content and quality). In addition, anthropogenic practices strongly modify climatic conditions, impact nutrient cycling and cause an input of man-made substances and toxins, which may shift or even tilt the natural equilibrium of microbial communities and processes in soil.

In a series of oral and poster presentations this session will present advances in soil biological and functional diversity. Topics presented in this session will include, but are not limitted to, the formation of soil microbial community structures and activities under the effects of i) temperature and soil moisture fluctuations (climatic factors), ii) plant community types (forests, grasslands, biological soil crusts, agricultural lands) iii) various agricultural practices (including flooding, application of mineral and organic fertilizers). Particular attention will be given to the i) separation of the effects of climatic and biotic factors, and ii) simultaneous estimation of microbial community structure and activity to reveal the driving factors for both. Overall, this session will give a broad overview about the effect of environmental conditions on formation and functioning of biological communities in soils and possible new research directions.