Lec 22 Sustainable Agricultural Production

Soil Conservation

reducing topsoil erosion and restoring soil fertility

Terracing
Contour Planting
Strip Cropping with cover crops
Alley cropping/agroforestry

Terracing

converting steeply sloped land into a series of broad, nearly level terraces that run across the land's contours

Contour Planting

plowing and planting crops in rows across of perpendicular to slopes rather than vertical or up and down the slope

Strip Cropping with cover crop

alternating strips or row crops and cover crops

cover crops are things like oats, rye, alfalfa, greens -- plants that trap soil that may erode from the row crop

Alley Cropping / Agroforestry

Crops are planted together in alleys between orchard trees or fruit bearing shrubs

how does this help erosion?:
windbreaks
shade prevents water loss by evaporation
deeper root structure of trees
plus, biodiversity!!

Hydroponics

growing plants by exposing their roots to a. nutrient rich water solution instead of soil, usually inside a greenhouse

Benefits of hydroponics

less water used
option to grow vertically -- space saver
year-round supply of certain plants
can sell to a niche market
can grow in cities -- local growing; lower carbon footprint -- also uses unused or abandoned land and space to grow and be productive

Drawbacks of hydroponics

large energy consumption
not a big profit at the beginning -- difficulty in setting up these systems and becoming successful

Aquaponics

hydroponics that includes fish

wastewater from fish tanks can be cycled into hydroponic troughs to nourish the plants

allows greater amounts of nitrogen to cycle back up to the plants

Organic Fertilizer

helps restore soil fertility

animal manure
green manure
compost (forced decomposition of food/yard waste)

Crop Rotation

helps restore soil fertility

change the crops you plant on a piece of land -- doesn't use up all the stores of a nutrient at once
certain plants can restore/preserve nutrients

USDA defines organic as...

practices that cycle resources, promote ecological balance, conserve biodiversity

no chemicals or synthetic pesticides/herbicides

this can include cover crops, organic fertilizers, crop rotations

use of biological control and crop rotations to manage insects, weeds

emphasis on biodiversity in cropping system and surrounding environment

often very physically exhausting - lots of manual labor involved

Perennial Polycultures

perennial = lives for 2 or more seasons before needing to be replanted

polyculture = growing more than 1 plant in an area

benefits:

better pest control, biodiversity, less laborious for farmers, no tilling (less soil erosion), variety of nutrients in soil, water used more efficiently

Renewable energy

focusing more on renewable energy sources in ag production is a feature of sustainable ag

wind, solar, water, biogas digesters

Anaerobic Digesters

can produce energy

envi benefits:
lowers food waste % of greenhouse gas emissions
reduces gas emissions from livestock too
closed-loop energy -- maximizes energy sources and reduces waste overall

Econ benefits:
companies get to purchase energy at a discount
farmers get electricity for free
farms save a ton of money
participating stores can save money bc food waste is expensive

Ways to support sustainable ag

buy local -- reduced carbon footprint, supports local economy

participate in community-supported ag
reduce food waste