Relationships between soil and water and their physic-chemical characteristics with plant growth and development. Water cycle in the soil and soil capacity to hold water, required plant nutrition elements, evaporation, transpiration, and evapo-transpiration. Soil role for water storage on the interface between aquifer and surrounding atmosphere. Methods water preservation in the soil minimizing water evaporation from the soil surface and transpiration from plants, plant response to water scarcity and the corresponding effects on nutrients availability, salinity effects, and heavy metal pollution on soil properties and plant growth. Use of plants for the treatment of wastewater, biosolids and polluted soil sites measurement tools of water content in soils and plants.