Agriculture
Marginal Food Security- Anxiety at times in accessing food, but in the end it’s not reduced overall the quality and getting the food
Low Food Security- Reduced their diets, but the food intake and eating patterns aren’t disrupted
Very Low Food Security- They’re food intake and eating patterns is disrupted
Undernutrition- Too few calories
Malnutrition- Too few nutrients
870 million people- do not eat enough
12-14%- of individuals in US are food insecure
Economic- Undernutrition cause
38%- land for agriculture
11%- arable land
77%-croplands (growing plants for human use)
16%-rangelands, pastures, feedlots (land used for grazing livestock)
7%- aquaculture
Wheat, rice, core- important crops
Raising crops- positive feedback loop (neolithic)
Subsistence farming- families feed themselves
Intensive farming- produce excess food to sell in market
Polycultures- traditional farming
Monocultures- more efficient
90%- food comes from 15 crop species and 8 livestock species (monocultures)
25% cropland- industrialized farming
80% food supply- industrialized agriculture
17 % of commercial energy in U.S- industrialized farming
Food travels 2,400 km- from farm to plate in U.S
Green revolution- prevented deforestation and biodiversity from converting old land
Produced wheat from green rev.-India, Pakistan, & Mexico
Conservational Tillage (no till)- crop residue is left behind
No till advantages- increases benefits of soil, reduces erosion, prevents carbon from entering atmosphere (carbon sequestration), adds organic matter, reduces fossil fuels
No till (conservational) disadvantages- increase herbicide, additional nitrogen fertilizers, decreases erosion, increase fungal disease, can’t be grazed, special machinery
No till (conservational) combatting disadvantages- green manure, rotate fields with cover crops, nutrients added to drip irrigation, application of fertilizers with seeds
40% US farmland- uses conservational tillage
Brazil, Argentina, Paraguay- over half of all cropland is now under no-till cultivation
Traditional Tillage advantages- high rates of incorporation
Tropical rainforest- slash & burn
Consequences of slash & burn- burning oxidized carbon, only some regrowth in land
Organic Fertilizers- Low concentrations = larger applications, Organic material increases water holding capacity, Increases nutrient holding capacity, expensive if bought
Inorganic Fertilizers- Soluble- immediately available to plants, Short duration because they leach away faster, Do not improve water holding capacity
Increased soil degradation vulnerability- Clearing forests on steep slopes or with larger clear-cuts
Soil Degradation severe- in arid areas
Soil Degradation primarily caused by- wind and water erosion
Prior to industrial agriculture in the Great Plains-the native short-grass prairie held the soil in place
Dust Bowl-massive dust storms from erosion of millions of tons of topsoil in the 1930s
Overgrazing can cause soil compaction-Harder for water to infiltrate, etc. more soil disadvantages
Overgrazing occurs when many animals eat too much plant cover-Impeding regrowth, Prevents replace of biomass
Overgrazing creates- a positive feedback loop/cycle (erosion)
Crop typical rotation- corn–> soybean → oats → alfalfa
Terracing- Reduces water erosion
Contour, strip and terracing help control- erosion on farmland with variable topography
Intercropping (different crops)- Slows erosion by providing more ground cover, Decreases vulnerability to insects and disease, when using legumes, replenishes the soil with nitrogen
Shelterbelts/Windbreaks- Lessens the impact of wind erosion
Feedlots/ CAFOS- reduces the impacts of overgrazing
Methane emissions- from animals and is most damaging
Drift netting- large nets float (schooling fish)
Longline fishing- tuna and swordfish
Recirculating aquaculture systems- are an alternative to open pen
GM crops- decrease biodiversity (environmental disadvantage)