Water environmental services: quantifying the effects of PPA’s functionality on multi-scale watersheds

Abstract

Terrestrial ecosystems provide a variety of goods and services essential to the existence and well-being, including, for example, water ecosystem services (WES) to regularize the flow, mitigation of floods and droughts, erosion control and sedimentation, preservation water quality, slope stabilization, recharge of soil moisture and aquifers, provided by riparian forests. Maintaining the provision of ecosystem services (ES) depends on the conditions (structure, operation, extension) of natural ecosystems within the watershed. The loss and degradation of these ecosystems results in a reduction in WES. In Brazil, the law governing the protection of natural ecosystems is the Brazilian Forestry Act (BFA). The land use that do not conform to BFA requirements is very expressive, for both riparian Permanent Protection Areas (PPAs) and Legal Reserve Areas (LRA), and the effects on the WES due to the non-compliance with the law still are unknown. This research proposes to estimate the WES resulting from the restoration of permanent protection areas (PPAs) in basins of different spatial scales (large and small scale) and land use (disturbed and protected).To achieve this aim an approach encompassing observational and modelling methods. The observational component involves (i) the analysis of the long term rainfall and runoff variability basins to diagnose the hydrological status of river basins; and (ii) to process and to ensure the quality of data obtained by the experiments with Hydroclimatic Geosensors Wireless Networks (HGEON) to be installed in two watersheds (one of Atlantic Forest and the other one predominantly occupied by pastures). The modeling component involves three steps. (i) Application of the Distributed Biosphere-Hydrological Model (DBHM) for small watershed and a large river basin (Mogi-Guaçú River Basin). The data from HGEON, the flux towers and hydrometeorological stations will be used as input to DBHM (eg: air temperature and relative humidity, precipitation) and to the regional validation (pex: soil moisture, the aquifers level, discharges, and heat and water fluxes). (i) Land use scenarios analysis to determine the WES generated from (a) restoration of the two types of APPs and APPs with different densities, (b) recovery of RL with the implementation of agroforestry systems. (iii) Comparison between the results of the scenarios through hydrological indices generated by the Invest model, and the valuation of WES for each scenario. We hope the results will serve as tools to support public policies for environmental and water resources management by providing appropriate indicators for evaluation (and valuation) of WES and the impacts of human activities on these services. (AU)