Forest restoration rehabilitates soil multifunctionality in riparian zones of sugarcane production landscapes

Author(s)

Bieluczyk, Wanderlei ; Merloti, Luis Fernando ; Cherubin, Mauricio Roberto ; Mendes, Lucas William ; Bendassolli, Jose Albertino ; Rodrigues, Ricardo Ribeiro ; de Camargo, Plinio Barbosa ; van der Putten, Wim H. ; Tsai, Siu Mui

• Document type: Journal article
• Source: Science of The Total Environment; v. 888, p. 15-pg., 2023-05-24.

Abstract

Brazilian sugarcane plays a vital role in the production of both sugar and renewable energy. However, land use change and long-term conventional sugarcane cultivation have degraded entire watersheds, including a substantial loss of soil multifunctionality. In our study, riparian zones have been reforested to mitigate these impacts, protect aquatic ecosys-tems, and restore ecological corridors within the sugarcane production landscapes. We examined (i) how forest resto-ration enables rehabilitation of the soil's multifunctionality after long-term sugarcane cultivation and (ii) how long it takes to regain ecosystem functions comparable to those of a primary forest. We investigated a time series of riparian forests at 6, 15, and 30 years after starting restoration by planting trees (named 'active restoration') and determined soil C stocks, & delta;13C (indicative of C origin), as well as measures indicative of soil health. A primary forest and a long-term sugarcane field were used as references. Eleven soil physical, chemical, and biological indicators were used for a structured soil health assessment, calculating index scores based on soil functions. Forest-to-cane conversion reduced 30.6 Mg ha-1 of soil C stocks, causing soil compaction and loss of cation exchange capacity, thus degrading soil's phys-ical, chemical, and biological functions. Forest restoration for 6-30 years recovered 16-20 Mg C ha-1 stored in soils. In all restored sites, soil functions such as supporting root growth, aerating the soil, nutrient storage capacity, and provid-ing C energy for microbial activity were gradually recovered. Thirty years of active restoration was sufficient to reach the primary forest state in overall soil health index, multifunctional performance, and C sequestration. We conclude that active forest restoration in sugarcane-dominated landscapes is an effective way to restore soil multifunctionality approaching the level of the native forest in approximately three decades. Moreover, the C sequestration in the re-stored forest soils will help to mediate global warming. (AU)

• FAPESP's process: 18/19000-4 - Applying the biotic soil legacy approach to understand positive-negative biota interactions for direct forest restoration from plant-soil communities feedbacks - BioFor
• Grantee: Tsai Siu Mui
• Support Opportunities: BIOTA-FAPESP Program - Regular Research Grants
• FAPESP's process: 20/15230-5 - Research Centre for Greenhouse Gas Innovation - RCG2I
• Grantee: Julio Romano Meneghini
• Support Opportunities: Research Grants - Research Centers in Engineering Program