Lecture 3

Detrimental effects of OrganicMatter• Soils with high organic matter contents may require higher pesticideapplication rates for effective control. Water contamination is then aconcern if these pesticides are leached or transported by wind orwater erosion.• Soils also have a finite capacity to sorb trace elements and shouldnot receive extensive applications of organic by-products such asmunicipal biosolids and animal manures that contain high levels oftrace elements.• Applications of by-products containing trace elements beyondallowable limits can lead to levels in soils that may be toxic to plants,and possibly to animals and humans upon consumption of foodsgrown in the contaminated soils or upon ingestion of the soil itself.