Soil organic matter, aggregate stability and respiration: integrated measures for the evaluation of the soil sustainability in the vineyards

In conventional viticulture, the frequent tillages and the massive use of agrochemicals have reduced soil organic matter content. Recently the conventional viticulture evolved in a more sustainable viticulture addressed to improve soil quality and better territory management. The purpose of this study was to evaluate the effects of different practices on soil organic matter and to establish relations with aggregate stability and microbial respiration indexes. In 2010, nine areas with different pedo-climatic characteristics were studied in Languedoc-Roussillon (South of France). Conventional and organic farmings managed with diverse agricultural practices chemical weed control (cwc), tillage (t) and cover crops (cc), were studied. The selected soil parameters studied were bulk density, aggregate stability, organic C, N total, microbial biomass carbon (MBC), basal respiration (BR), metabolic quotient (qCO2) and C/N ratio. Through the Mean Weight Diameter (MWD) has been possible to determine the precarious level on aggregate stability of vineyards. C/N ratio varied from 6.69 to 29.28, qCO2 varied from 0.5 to 1.46 mg CO2-C g−1 MBC resulting lower values in Scc clayey soil class, qCO2 was strongliy linked to the total organic carbon and soil texture. Br/Tot OC (I1) varied from 0.37 to 3.06 mg C g-1 resulting higher in CScwc and lower in Scc. The values of MBC/Tot OC (I2) ranging from 1.11 to 11.51 mg g−1 C. The results showed that sustainability indicators like C/N, qCO2, MBC/Tot C and BR/Tot OC can be used to assess vineyard soil quality