Hydrobiogeochemistry of two catchments in Brazil under forest recovery in an environmental services payment program

Authors: FIGUEIREDO, RICARDO - Embrapa; SIMIOLI, MATHEUS - Embrapa; JESUS, TALITA - Universidad De Sao Paulo; CRUZ, PATRICIA - Embrapa; NOGUEIRA, SANDRA - Embrapa; Green, Timothy; CAMARGO, PLINIO - Universidade De Sao Paulo

Submitted to: Environmental Monitoring and Assessment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/2020
Publication Date: 12/9/2020
Citation: Figueiredo, R.O., Simioli, M.R., Jesus, T.V., Cruz, P.P., Nogueira, S.F., Green, T.R., Camargo, P.B. 2020. Hydrobiogeochemistry of two catchments in Brazil under forest recovery in an environmental services payment program. Environmental Monitoring and Assessment. 193. Article e3. https://doi.org/10.1007/s10661-020-08773-6.
DOI: https://doi.org/10.1007/s10661-020-08773-6

Interpretive Summary: Two upland watersheds, Posses (PS) and Salto de Cima (SC) located in the municipality of Extrema, Minas Gerais, Brazil flow into the Jaguari River, an important tributary to the Cantareira Reservoir System, which supplies part of the water demand of the São Paulo metropolitan area. These agricultural and forested watersheds have been a focus of an environmental recovery under an Environmental Services Payment (ESP) program that aims to face the risk of water crisis in the region. Evaluations included comparison of two monitored streams in relation to measured water quality, since PS and SC are at different stages in the environmental recovery process. Monitoring activities in 2017 revealed an important pollution point source in the PS stream related to cattle or other unidentified sources, affecting the chemistry on some random days. The SC stream shows evidence of domestic sewage input. Overall, the study confirmed some improvement of the stream water quality in response to recovery of the forest vegetation. Therefore, we recommend that watershed management practices regarding anthropic effluents must be considered in the ESP program to accomplish its purpose. We also recommend electric conductivity as an indicator of ESP program results.

Technical Abstract: Posses (PS) and Salto de Cima (SC) catchments (1,200 ha and 1,500 ha, respectively) are situated in the municipality of Extrema, Minas Gerais. Their streams flow into the Jaguari River, an important tributary to the Cantareira Reservoir System, which supplies part of the water demand of the São Paulo metropolitan area. These pastoral catchments with high topographic relief have been a focus of an environmental recovery under an Environmental Services Payment (ESP) program that aims to face the risk of water crisis in the region. The present hydrobiogeochemical study evaluates possible improvements of water resources. Evaluations included the temporal variation of hydrogeochemical parameters as well as a comparison of two monitored streams in relation to these water quality variables, since their catchments are at different stages in the environmental recovery process. Samples were collected manually for chemical analysis and physical-chemical field measures every two weeks from January to December 2017. This monitoring activity revealed an important pollution point source in the PS stream related to bovine urine and feces or other unidentified source, affecting the fluvial hydrogeochemistry on some random days and times. At SC stream, on the other hand, there is evidence of domestic sewage input. Overall, the study confirmed some improvement of the stream water quality in response to recovery of the forest vegetation. Therefore, we recommend that other watershed management practices regarding anthropic effluents must be considered in the ESP program to accomplish its purpose. Considering the presented results we can also recommend the use of electric conductivity as an indicator parameter of the real effects of such program.