Physical, Chemical, and Biological Indicators of Soil Quality in Mediterranean Vineyards under Contrasting Farming Schemes

The soil of most Spanish vineyards is strongly eroded and carbon depleted and is very poor in biodiversity. Growing evidence of the negative impacts of soil degradation on climate change mitigation, water quality, and plant production is pushing a shift from intensive viticulture to more sustainable management strategies of the vineyards. Among them, minimum impact and regenerative viticulture are gaining ground. However, field data are still necessary to assess the real effect of these new farming schemes on soil carbon stocks and soil functional biodiversity. We compared soil quality at three vineyards managed under intensive, regenerative, and minimum impact strategies using physical, chemical, and biological indicators. Soil carbon stocks were 2.3 and 3.4 times greater in the regenerative and the minimal impact vineyards than in the intensive vineyard, respectively. Soil biota was particularly favored by regenerative viticulture, with 26.2 times more protists, 3.1 times more nematodes, and 29.4 more microarthropods in the regenerative than in the intensive vineyard. Our results indicate that the ecological intensification of agricultural practices is highly promising to restore degraded agricultural soils under Mediterranean conditions. We also propose cost-effective soil bioindicators sensitive to agricultural management for their possible inclusion in soil monitoring programs.