GEOG 001 Lecture Notes - Lecture 10: Overgrazing, Darfur, Intertropical Convergence Zone
10 Aug 2020
School
Department
Course
Professor
Document Summary
Overgrazing- cannot withstand intensive grazing due to semi-arid vegetation, sedentary intensive farming not induced to moving with rain, reduce biodiversity, breaks up soil, removes binding properties of roots and biomass. Vegetation removal- by grazing animals, direct removal of woody vegetation by humans. Erosion- exposed to wind and water since vegetation removed, creates dust storms and net loss of soil, deseritifed land tends to stay desertified because removal of topsoil prevents plants being re-established. Sahel (desert area)- very dry, climate controlled by monsoons to south, and north descending arms of hadley and ferrel cells. Southern boundary of sahara (north)- rainfall determined by position of seasonal rain belts. Rainfall increases north to south- saharan regions receiving low and intermittent rainfall. Sahelian regions ranges between 100-500mm/year and savana regions. Trade winds converge at itcz- low atmospheric pressure creates gradient creates high pressure in rushing winds.
