Changes in Brazil's Forest Code can erode the potential of riparian buffers to supply watershed services

Autor(es)

Guidotti, Vinicius ^{[1, 2]} ; de Barros Ferraz, Silvio Frosini ^[3] ; Guedes Pinto, Luis Fernando ^[1] ; Sparovek, Gerd ^[4] ; Taniwaki, Ricardo H. ^[5] ; Garcia, Lara Gabrielle ^[3] ; Brancalion, Pedro H. S. ^[3]

Afiliação do(s) autor(es)

^[1] Inst Agr & Forest Management & Certificat Imaflor, Estr Chico Mendes 185, BR-13426420 Piracicaba, SP - Brazil

^[2] Univ Sao Paulo, Ctr Nucl Energy Agr, CENA, Av Centenario 303, BR-13416000 Piracicaba, SP - Brazil

^[3] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Forest Sci, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

^[4] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Soil Sci, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

^[5] Fed Univ ABC, Ctr Engn Modelling & Appl Social Sci, Av Estados 5001, BR-09210580 Santo Andre, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: LAND USE POLICY; v. 94, MAY 2020.
• Citações Web of Science: 0

Resumo

In Brazil, the Forest Code requires landholders to maintain fixed-width buffers of native vegetation along watercourses - legally called Areas of Permanent Preservation (APPs). In 2012, agricultural activities started to be partially allowed in APPs, but only if best management practices on soil and water conservation are adopted and if a narrow buffer strip with native vegetation is restored adjacently to the watercourse. In this paper, we present a modeling framework to investigate the capacity of legal compliant APPs to supply watershed services (erosion control and stream bank stabilization) in a 2,200 ha watershed in Sao Paulo State, Brazil. Our results suggest that the narrower the riparian buffer the lower the control of soil erosion dynamic within APPs, and that riparian buffers smaller than 8 m can act as a source of sediments to streams. The adoption of best management practices can contribute to controlling soil erosion within APPs but the presence of native forests in the first 15 m is necessary to guarantee equivalent protection to streams when compared to APPs completely covered by forests. Moreover, we observed that forest restoration within APPs helped to reduce the average soil loss of the watershed by only 20 %, compared to a reduction of 55 % when best practices are implemented in all watershed agricultural areas. We conclude that (i) the reduced requirements for APP restoration may contribute to stream sedimentation, which will likely affect the supply of watershed services by stream ecosystems; (ii) the implementation of best management practices in APPs will not have the same effect as native forests to reduce stream sedimentation; and (iii) the adoption of best management practices in all agricultural production areas and not only within APPs as required by law - is the best strategy to promote the supply of watershed services to society. (AU)

• Processo FAPESP: 16/17680-2 - Áreas prioritárias para compensação de Reserva Legal: pesquisa para o desenvolvimento de uma ferramenta para auxílio à tomada de decisão e transparência no processo de implementação do Programa de Regularização Ambiental (PRA) no estado de São Paulo
• Beneficiário: Gerd Sparovek
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático