RS 478 Lecture Notes - Lecture 12: Germination, Silt, Geotextile
Document Summary
Rs 478: lecture 12 physical limitations to soil restoration. The long term treatment is to increase biological activity (rooting, litter, soil critters: too open soil is initially treated by compacting or covering with fine material. The hydrophobic layer is the result of a waxy substance that is derived from plant material burned during a hot fire. Reduction in total soil nutrients (-), difficult to till or plow (-), poor seed-soil contact in seedbed (-): elevated surface temperature (higher heat capacity than soil) (-/+) Increased infiltration (+), increased macroporocity (+), reduced susceptibility to compaction (+), reduced evaporation (if on surface) (+), increased safe sites for germination (if on surface) (+): rock fragments: rocks can be removed using a soil sifter. But, not practical in most restoration settings: organic matter benefits: Improves whc especially in sandy or rocky soils improves infiltration especially in fine-textured soils reduces evaporation. Improves nutrient relations: adds cec, adds nutrients substrate for microbes.