Department of Earth and Environmental Science

Alain F. Plante

Research program

Our research team seeks to characterize the quantity, quality and function of organic matter in surface soils from various ecosystems.

The interactions between organic and mineral materials are a fundamental feature of soils, differentiating them from geologic parent materials. Soil is primarily a mineral matrix (except in organic soils such as peat), but receives inputs of organic matter from various natural sources such as surface litter, root turnover and exudation, or from various anthropogenic sources such as manure additions. As this material is decomposed by soil fauna and microorganisms, it is physically and biochemically transformed into humified soil organic matter that is stabilized by various mechanisms. Interactions between organic matter and soil mineral surfaces occur at the nano- to micro-scale, but their impacts are felt up to the global scale.

1500-2000 billion metric tons of carbon are stored in the top meter of the Earth's soils, making it the largest of the active terrestrial carbon pools. Although soil organic carbon is essential to both soil fertility and global carbon budgets, the size of the global soil carbon pool has declined by 50-70% in the past 150 years due to land use changes. These historic losses now represent an opportunity to enhance carbon storage through conservation practices that promote soil carbon sequestration and fertility in croplands, rangelands and forests. For these reasons, soil organic carbon has become an object of considerable scientific interest.

Current projects