BIOL 201 Lecture Notes - Nitrifying Bacteria, Nitrogen Cycle, Hectare
Document Summary
Clearing of forests for agriculture or buildings; cleared areas may be mined for mineral ores; timber obtained may be used for paper, charcoal, furniture, building material. Increases velocity of rain reaching the soil: soil erosion / leaching of ions. Reduces biodiversity: more extreme environment / abiotic factors increase / unstable ecosystem, change in (micro)climate / levels of light / temp / humidity, loss of niches/habitats and complex food webs, animals move away/higher death rate/extinction. Growth in human population is increasing the demand for agriculture for land for farming for grazing land to provide animal protein. Ions from fertiliser readily leach out of the soil by rain into lakes and rivers. [exam] ploughing increases the activity of nitrifying bacteria in the soil: oxygen enters the soil, nitrifying bacteria are aerobic, convert ammonia/ammonium ions to nitrite, nitrite to nitrate, nitrate is absorbed/used by plants, to make protein/amino acids/dna/atp/nad(p)/chlorophyll. Lower co2 (greenhouse gas) uptake by photosynthesis.
