Apes 5.3 The Green Revolution

The Green Revolution

Shift in agriculture away from small, family operated farms to large, industrial-scale agribusiness/Increased use of mechanization, GMOs, irrigation, fertilizers, and pesticides

Positives outcomes of green revolution

Greatly increases efficiency of lands, short-term profitability, and food supply + Decreased world hunger and increased earth’s carrying capacity for humans

Negative outcomes of green revolution

soil erosion, biodiversity loss, ground & surface water contamination

Mechanization

using machines (like tractors, harvesters) in agriculture to replace human/animal labor, boosting food output (yields) and efficiency

Positives of mechanization

Increased use of tractors for plowing and tilling fields, and combines for harvesting = increased yield + profits

Negatives of mechanization

Increases reliance on fossil fuels (gasoline/diesel fuel) - Emits GHGs to atmosphere → climate change - Heavy machinery also compacts soil, decreasing H2O holding capacity - Makes topsoil more prone to erosion

High-Yield Variety (HYV) crop

a strain of a crop that has been selectively bred or genetically modified to produce a significantly greater amount of harvest (yield) per unit of land compared to traditional varieties. 

GMOs

Crops that have genes for drought tolerance, pest resistance, faster growth, and larger fruit/grain

Increases profitability with fewer plants lost to drought, disease, or pests + larger plant size + yield/acre

Positive outcome of use of gmos

GMO crops are all genetically identical so gen. diversity is decreased and susceptibility to diseases or pest is increased

Negative outcome of use of gmos

Synthetic Fertilizer

fertilizers that are (man made ammonium, nitrate, phosphate)

Increases yield and profits with more key nutrients needed for plant growth (N, P, K) added to the soil

Positive outcome of using synthetic fertilizers

Excess nitrate, phosphate are washed off fields and into nearby waters where they cause eutrophication (algae blooms) - Require FFs for production, releasing CO2 (climate change)

Negative outcome of using synthetic fertilzers

Irrigation

Drawing water from the ground or nearby surface waters and distributing it on fields to increase plant growth

Make agriculture possible in many parts of the world that are naturally too dry (don’t receive enough rain)

Positive outcome of using irrigation

Can deplete groundwater sources, especially aquifers - Over watering can drown roots (no O2 access) and cause soil salinization (increase salt level in soil)

Negative outcome of using irrigation

Pesticides

chemicals sprayed on crops that kill weeds, insects, rodents and other pests that eat or damage crops

Increases yield and profits with fewer plants lost to pests

Positive outcome of using pesticides

Can wash off crops in runoff and kill or harm non-target species in local soil or waters (bees especially) - Ex: DDT thinned shells of bird eggs, especially eagles Atrazine turns amphibians and fish intersex

Negative outcome of using pesticides