5.3 Green Revolution, 5.4 Impacts of Agricultural Practices, and 5.14 IPM Pros and Cons

Mechanization Pros

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

Mechanization Cons

- Increases reliance on fossil fuels (gasoline/diesel fuel) leading to greenhouse gas emissions that contribute to climate change

- Heavy machinery also compacts soil, decreasing H2O holding capacity. Makes the soil more prone to erosion

GMOs Pros

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

GMOs Cons

Crops are genetically identical so genetic diversity is decreased and susceptibility to diseases or pest is increased

Synthetic Fertilizers Pros

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

Synthetic Fertilizers Cons

- Excess nitrate, phosphate are washed off fields and into nearby waters where they cause eutrophication (algae blooms)

- Require fossil fuels for production, releasing CO2 contributing to climate change

Irrigation Pros

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

Irigation Cons

- Can deplete groundwater sources, especially aquifers

- Over watering can drown roots (no O2 access) and cause soil salinization (increase salt level in soil)

Pesticides Pros

Increases yield and profits with fewer plants lost to pests

Pesticides Cons

Can wash off crops in runoff and kill or harm non-target species in local soil or waters (bees especially)

Monocropping Pros

Highly efficient for harvest, pesticide and fertilizer application

Monocropping Cons

- Greatly decreases biodiversity (more prone to pests, fewer natural predators)

- Increases soil erosion (crops harvested all at once & soil left bare)

- Decreases habitat diversity for species living in the area

Tilling Pros

Mixing and breaking up soil to make planting easier. Looses soil for roots

Tilling Cons

- Increases erosion by loosening topsoil, breaking up leftover root structure from harvest

- Loss of organic matter & topsoil nutrients over time

- Increased Particulate Matter (PM) in air (respiratory irritant) and sediments in nearby water (turbidity)

Slash-and-burn farming Pros

Clears land for agriculture & returns nutrients in plants to soil

Slash-and-burn farming Cons

- Deforestation leads to loss of: habitat, biodiversity, CO2 sequestration (storage), loss of air pollution filtration

- Releases CO2 contributing to climate change

IPM Pros

- Reduces death & mutation of non-target species from pesticides

- Reduces effects on human consumers of produce

- Reduces contamination of surface & ground water by agricultural runoff with pesticides

IPM Cons

Can be more time consuming & costly than just crop dusting pesticides