Vol. 76 No. 4 (2021):

Soil functions and the role of biological activities

Paolo Nannipieri
Professor Emeritus, University of Florence, Italy

Published 2021-09-15


  • soil quality,
  • functional redundancy,
  • amplicon sequencing,
  • N reactions,
  • stable isotope probes


Despite soil is a thin layer covering terrestrial Earth surface, it carries out functions that are essentialfor the terrestrial life forms and these functions are mainly conducted by soil microorganisms, such asfungi and bacteria. They live in a complex, structured and peculiar environment. Microbial diversityis huge and soil is considered the most biodiverse ecosystem on Earth because a handful of soil cancontain thousands of millions microbial cells. Despite the high microbial biomass only less than 1%of the available space is occupied by soil microorganisms because most of the available microenvironmentsshow conditions hostile to microbial life. The application of molecular techniques has markedlyimproved the knowledge of the microbial life and activity in soil. In particular, the microbial speciesinhabiting soil can be detected whereas the expression of genes is still a technical challenge. Gross ratesof nutrient transformations can be determined by using labelled compounds with positive implicationson the evaluation of soil nutrient dynamics, including availability for plants.