29 May Communication at the 3rd Global Soil Biodiversity Conference
Impact of Long-term Phytomanagement of Cu/Pb Mine Tailings on Soil Biochemical Functionality
Ángeles Prieto-Fernández, Beatríz Rodríguez-Garrido, Carmela Monterroso, Carmen Trasar-Cepeda
3rd Global Soil Biodiversity Conference, March 2023, Dublin
The study evaluates the long-term effects on soil functionality of different phytomanagement options in a former Pb/Zn mine in the temperate-humid zone of Spain. The long-term influence of willow (Salix smithiana Willd) plants, either as monoculture or intercropped with alder (Alnus sp.), and soil organic amendments (green compost) or inorganic fertilization (NPK) on several soil enzyme activities was evaluated. Results from phytomanaged soils are compared with those obtained in unplanted soils, untreated or treated with compost. In the absence of compost amendment, the soil enzymatic activities in the willow monoculture plots (with near neutral pH) tended to be even lower than in the unplanted plots. The addition of compost led to an increase in soil organic matter and in all enzyme activities. The highest values were observed in compost amended plots cultivated with willow in co-cropping with alder. When activity values are expressed per carbon unit, the positive effect of compost tended to disappear, except in intercropped plots. The addition of green compost combined with intercropping of willow with alder, appears to be a suitable management to increase and maintain in the long term the functionality of mine tailings soils contaminated with Pb/ Zn/Cd and with pH close to neutrality.