ENV100Y5 Lecture Notes - Lecture 23: Soil Retrogression And Degradation, Soil Compaction, Land Degradation

• School: UTM
• Department: Environment
• Course: ENV100Y5
• Professor: Barbara Murck

Document Summary

Soil degradation has many causes: soil degradation results from deforestation, agriculture, overgrazing, chemical contamination, etc, over the past 50 years, soil degradation has reduced global grain production (by 13%) Grazing practices can contribute to soil degradation: compacts soil and damages structure, decreases water infiltration, decreases grass growth and survival, etc, holistic management = simulating the behaviour of natural herds actually improves/preserves soil. Irrigation boosts productivity but can cause long-term problems and soil degradation: groundwater depletion, waterlogging, salinization = buildup of salts in surface soil layers, problems with irrigation, expensive, alters root morphology. Increase fungal pathogens: can cause salinity problems, subsidence (downward shift of surface, salinization is easier to prevent than to correct, very costly and difficult to rehabilitate salinized soil. Phytoremediation type of bioremediation (using living organisms to clean up contaminants: phytoextraction: drawing chemicals up into plant biomass by action of plants that are hyper accumulators, e. g. hydrangea is a hyper accumulator of al.