ECCO

The impact of climatic variability and land cover change on connectivity in the soil-plant-atmosphere continuum (SPAC) and on ecohydrological water storage and partitioning is poorly understood. This limited understanding results from challenging required measurements and inadequate modelling techniques. Such understanding is particularly weak in the complex climate and landscape settings of Costa Rica or similar tropical developing regions which are under urgent pressures of global change. We will address this knowledge gap by developing a coupled, tracer-aided atmosphere ecohydrology modelling framework to assess feedback mechanisms of how changing climatic conditions, moisture sources and land cover modification affects hydrological response in terms of fluxes of evaporation, transpiration, runoff, and groundwater recharge in a large, strategically important catchment in Costa Rica (which allows multi-scale investigations). This project aims to understand how climate variability and land cover changes affect ecohydrological water partitioning across the SPAC and how local scale processes can impact larger scales in tropical regions.

The proposed novel coupled model system will allow quantification of largescale, historic land cover change and its impact on water partitioning in a tropical test catchment that possesses a wealth of pre-existing hydrometeorological and isotope data. More specifically, we will address the following two research questions that directly map onto two work packages:

1. Can we better characterize and quantify ecohydrological partitioning and feedbacks in a large (>1000km2) humid tropical catchment using isotope tracking within a coupled, process-based ecohydrological and regional climate modelling framework? 
2. ii) How will land cover change (e.g., from lowland forest to pineapple monoculture) affect ecohydrological partitioning, and how will this feedback into rainfall patterns, temperature, recycled moisture transport and water availability in the humid tropics?

This project, jointly led by an internationally renowned team, has the potential to advance our knowledge of how the SPAC responds to situations of hydrological extremes in the humid tropics of Central America to assess the resilience and recovery of water resource systems to stressors such as droughts.