Manpreet Singh Mavi

Dissolved organic matter dynamics in salt affected soils

Understanding Soil Organic Matter (SOM) and nutrient dynamics in salt affected soils is crucial for successful crop production. Despite the extent of salt-affected soils in Australia, little is known about turnover and loss of Dissolved Organic Matter (DOM) in these degraded environments.

DOM losses in the salt-affected soils are expected to be high due to solubilisation of organic matter in the sodic soils and decreased microbial activity in saline soils. This will further decrease the carbon stocks and productivity of these marginal soils. Due to the paucity of SOM in Australian top soils and the importance of DOM turnover for upland carbon balance and nutrient release, it is essential that factors and processes that alter DOM concentrations are well understood, particularly for soils with poor structural stability and low inputs of soil organic matter such as affected by salinity.

Manpreet’s study will provide relevant information on the dynamics of dissolved organic matter from salt-affected soils under various management conditions which may have important implications for sustainable agricultural production and the environment.

Manpreet’s research falls into the CRC’s Program 2 research area.

Objectives:

• Study the effect of salinity, sodicity and texture on DOM and nutrients (C, N, P) availability in salt-affected soils
• Investigate the effect of soil moisture (drying and wetting cycles) on dynamics of DOM and nutrients dynamics in salt-affected soils
• Evaluate the effect of organic (residues and manures) and inorganic (mineral fertilizers and gypsum) amendments on leaching of DOM and nutrients in salt-affected soils.

For more information, email Manpreet.