The impact of salinity on the interaction between water and ecological systems

Background/Question/Methods

Soil salinization is a widespread form of land degradation, which poses considerable threats to food security, sustainable development, and the functioning of natural ecosystems. Globally, soil salinity already affects more than 10% of the emerged land and is expected to intensify due to climate change, sea-level rise (SLR), and unsustainable agricultural practices. The resilience of natural and managed ecosystems to soil salinization depends on a variety of processes related to plant-environment interactions in the critical zone. Vegetation has evolved to cope with salinity through an ensemble of mechanisms that largely resemble drought-tolerant plants’ strategies in response to water stress. Plant hydraulic traits largely mediate the response to low soil water potentials in both drought-tolerant and salt-tolerant species - and with it, the way soils, plants, and the atmosphere interact in salt-affected ecosystems.

Results/Conclusions

This contribution explores the impact of salinity on the interaction between water and ecological systems at spatial and temporal scales ranging from the plant to the river basin. We focus on how salinity affects the bi-directional interaction between vegetation and its physical environment. Using both process-based models and observations, we unveil the central role of plant-salt tolerance in regulating soil-plant-atmosphere interactions and show how salinity acts as an aridity enhancer.