A meta-analysis of the ecological impact of viticultural practices on soil biodiversity

Abstract

Context and purpose of the study – Viticulture is facing two major challenges – climate change and agroecological transition. The soil plays a pivotal role in these transition processes. Therefore, soil quality and adequate soil management are key levers for an ecologically and economically sustainable viticulture. Over the last 15 years, numerous studies evidenced strong effects of viticultural practices on the soil physical, chemical and biological quality. However, to date a global analysis providing a comprehensive overview of the ecological impacts of viticultural practices on soil biological quality is missing.

Material and methods – We conducted a meta-analysis of the international literature in order to rank viticultural production systems and practices according to their impact on soil biodiversity and functioning in the context of the agro-ecological transition. We screened about one hundred articles and gathered data on more than 50 viticultural factors and 230 soil biological parameters. The viticultural factors were classifed into different groups, i.e., the land-use, the method of production, practices. The biological groups were distributed into macrofauna, mesofauna, microfauna, and soil microorganisms. The measured parameters addressed 3 main properties of soil biological quality: biological heritage, functional and sanitary states of the soils.

Results – The results show that the soil microorganisms are threefold to fourfold higher under organic viticulture than under conventional viticulture in terms of biomass, respiration, and activity; and that biodynamic viticulture shows a similar trend than organic viticulture. Tillage, the absence of soil cover and mineral fertilization are significantly deleterious to the whole soil biodiversity, whereas cover crops, organic fertilizers and addition of grapevine pruning wood are beneficial. Pesticides—especially herbicides—have an ecotoxicological impact on soil organisms, notably on nematodes with losses of up to two-thirds of individuals. Our study also highlighted some unexplored themes which need to be investigate such as pesticides other than herbicides, copper use as fungicide, or biocontrol tools. A well knowledge of the impact of viticultural practices on the soil biodiversity should provide the key for improving the sustainability of viticultural soils to preserve them from irreversible degradations with substantial consequences on the soil ecological and agronomical services for vine production. This work and all the informations and results have been published in 2020 in Environemental Chemistry Letters (see Karimi et al. 2020).