Critical zone research has emerged as an interdisciplinary framework for the analysis of the complex coupled chemical, biological and physical processes operating together from vegetation canopy to bedrock to support life on earth. The critical zone encompasses a myriad of interacting processes. LandSense focuses on the spatio-temporal variation in soil hydrology and its controls on carbon and nutrients fluxes, which are highly relevant in the context of global change. Given the central role of the soil system in regulating carbon and nutrient fluxes, and the increasing environmental pressures, it is important to (i) improve fundamental understanding of these key critical zone processes by collecting targeted measurements using new sensing methodologies across spatial and hydrological gradients under contrasted conditions and (ii) to use this to capture process-feedbacks in coupled and integrated models of the crfitical zone. In addressing these needs, LandSense proposes to tackle the following overarching scientific question: What are the hydrological controls on soil processes controlling carbon- and nutrient-efflux in the critical zone at the landscape scale? This overarching research question is addressed by a set of more specific questions that are also reflected in the work packages of the project.
Q1: How does the spatial variation in critical zone morphology, structure and composition, that develops at longer time scales, constrain the links between hydrology and C/nutrients fluxes over shorter timescales?
Q2: Do vertical and spatial heterogeneities in soils create hotspots or hot-moments of biogeochemical functioning that have a disproportionate effect on landscape-scale process rates?
Q3: How and to what extent can a smart integrated data-model framework, based on high resolution geophysical and proximal sensing data and field observations, provide insights into process interactions and landscape scale budgets?
Q4: Across complex landscapes, what is the short-term response pattern of the processes controlling CO2 fluxes?
Q5: Across complex landscapes, what are the main parameters controlling the changes in soil water residence time, in soil redox conditions, in mineral-OC interactions, and in the end, the short-term response pattern of the processes regulating the lateral transfer of nutrients and DOC?
