GEOG 106 Lecture Notes - Lecture 15: Gully, Soil Structure, Aeration
Document Summary
Process of soil particles picked up and carried away by water or wind: water erosion. Splash erosion" impact of raindrops breaks up topsoil structure particles wash into other spaces and block pores (decrease infiltration and aeration) Running water carries away fine particles from surface. Gully erosion" water converges into streams, gaining greater volume, velocity and energy (sandpaper-divides up the land: water erosion model. Factors: erosivity: rainfall, runoff, erodibility: vegetation, topography, land use practices, soil properties (more prone to management) Impacts of soil erosion: quality reduction, fragmentation, sedimentation, transport, salinization, entrainment. Salinization of soil: occurs in semi-arid regions (dry and agriculture-heavily irrigated, salinization is the cause of irrigation, dissolves salts in the soil, hard to fix. Land degradation: from the interaction of land use and biophysical processes, reduced plant cover, reduced soil cover, reduced soil moisture reserves, agriculture capacity declines, water erosion, wind erosion, if vegetation is removed, erosion can kick in.
