Respiration index determination: Dynamic and static approaches

Forty-five organic matrices of different types and origin were subjected to the test for the determination of biological stability by means of dynamic respirometric measurement (DRI) and static respirometric measurement (SRI) . The results obtained from the comparison between the two indexes indicate d that the SRI, compared with the DRI underestimates the consumption of oxy gen by the biomasses and consequently their rate of biological stability by a factor equal to 2. From the analysis of the data it is possible to defin e the biological stability as DRI<1000 mgO(2)kg(-1)VSh(-1). The DRI data we re correlated with the temperatures of the biomasses showing a Linear corre lation (R-2=0.81, p<0.01) only for stable matrices while for nonstable matr ices no significant correlation is found.