Soil moisture and its importance in the water cycle

Soil moisture is an important but often undervalued element of the water cycle. Compared to other components, the volume of soil moisture is small; nonetheless, it is of fundamental importance to many hydrological, biological and biogeochemical processes. Through processes like evaporation and plant transpiration, soil moisture is a key variable in controlling the water and energy exchange between the land surface and the atmosphere, hence, it plays an important role in the development of weather patterns and the precipitation formation. It also strongly effects surface and subsurface runoff, soil erosion, food production, greenhouse gas emission, the buffer capacity of the soil, the soil biota and many other processes and sectors. It is deducable today that short-sighted mismanagement of soil or soil water strongly contributed to the collapse of large, powerful historic civilazations.

Soil degradation is a global problem that is of strong concern  for European countries as well. Yet, while much focus is given to open surface water recources - the EU Water Framework Directive is in place since 2000 - the Soil Framework Directive is still to be adopted. It is important to improve the global understanding of the importance of soil as a natural resource, and its hydraulic functioning, including its global change context. The presentation aims at taking a deeper insight into the “butterfly effect” of soil status and moisture dynamics by highlighting how small-scale management decisions and processes might influences large-scale processes and our life.