Soils as determinants of water quality and quantity

Background/Question/Methods: Soils play a critical role in providing ecosystem services critical for human well-being, and in regulating the resilience of these systems to environmental variations as well as human accelerated environmental changes. This presentation will focus on the soil’s regulating services, controlling both soil water availability and water quality, as well as on the soil properties and processes that determine and sustain these services.  We will use the soil ecosystem services framework put forth by Dominati et al. (Ecological Economics, 2010), to illustrate the inter-connectedness of soil services with the soil’s natural capital.

Results/Conclusions: We will present three case studies to illustrate the controlling role of soils. This includes the role of deep soil water on maintaining a healthy forested ecosystem, as analyzed from data collected at the Southern Sierra’s Critical Zone Observatory (CZO). The second example will demonstrate implications of using a range of soil management practices on fertilizer-nitrate leaching in agricultural ecosystems. Finally, mm-scale non-invasive measurements by using neutron tomography will exemplify the need for continued soil research to improve the understanding of coupled soil-plant root interactions, affecting both soil water availability and quality.