Data: 04/11/2024 à 07/11/2024
Local: Florianópolis-SC
Mais informações: https://www.abrhidro.org.br/iebhe
Assessing Native Forest Ecosystem Services in Water-Stressed Basins Through Hydrological Modeling
Código
I-EBHE0074
Autores
Pilar Andrea Barria Sandoval, Anahí Ocampo-Melgar, Alejandro Venegas, Claudia Cerda
Tema
WG 2.1: Drought in the Anthropocene
Resumo
The recent megadrought in the semi-arid region of Central Chile has intensified the ongoing water crisis. This scarcity, compounded by climate change projections, has led to significant regulatory reforms, including the enactment of the Framework Law on Climate Change (No. 24,455) and the reform of the Water Code (No. 21,435), both aimed at ensuring water security. To achieve this goal, the development of "Strategic Water Resource Plans in Basins (PERHc)" for the 101 Chilean basins has been mandated, utilizing the coupled WEAP and Modflow models as tools. These models simulate and evaluate various climate and land management scenarios, explicitly considering the social, ecosystemic, and productive functions of water. Climate and hydrology are governed by non-stationary processes that influence the responses of ecosystem functions, such as native forests, and their feedback effects on hydrology. A key challenge for modelers is reconciling the scales of analysis to explicitly incorporate forest responses to changing scenarios (ecosystemic function of water) with basin-scale processes. This integration is crucial for providing timely and relevant information for decision-making and building more resilient systems. This work proposed a modeling approach that integrated forest dynamics in response to changing scenarios into a semi-distributed model, thereby enhancing our understanding of the ecosystemic function of water within a model typically used to evaluate the operation of systems focused on productive activities. Furthermore, this model was useful to explore changes in several ecosystem functions that are necessary for ecosystem services provision. A significant relationship was found between the growth of hygrophilous forest, scrubland, sclerophyllous, and deciduous forest, and historical precipitation during winter, summer, November to May, and annual periods, respectively. This relationship allowed us to approximate forest growth in response to climate change projections. It was identified that the WEAP model could incorporate the relationship between native forest growth and water provision in response to climate change through the parameters Kc (crop coefficient) and RRF (runoff resistant factor). The WEAP model results indicate that during the historical period (2000-2019), the native forest provided approximately 0.73 m³/s of water, with 0.63 m³/s from groundwater recharge and 0.1 m³/s from surface accumulation, corresponding to increased infiltration and greater soil water retention for surface runoff availability. Additionally, under the SSP585 climate change scenario, the freshwater provision from the native forest is projected to increase to 1.68 m³/s for the decade 2050-2059, with 0.84 m³/s from groundwater recharge and 0.85 m³/s from surface accumulation