Agriculture. Is this what you think agriculture looks like?

Size: px
Start display at page:

Download "Agriculture. Is this what you think agriculture looks like?"


1 hh Agriculture Is this what you think agriculture looks like?

2 Nearly all U.S. Agriculture is now Industrial hh

3 Industrial Agriculture Machines & fossil-fuel energy replace human/animal energy Benefits: Produce a lot of food at low cost (after initial investment) Requires: $$, large expanse of ~ flat land, monoculture Practice of growing a single crop (or animal) in a large area Corn monoculture

4 Monoculture Efficient saves time, $, don t change machines..but Susceptible to pests & disease spread rapidly when 1 species is close together Rely heavily on pesticides, antibiotics Crops deplete organic soil nutrients Crop yields over time Rely on fertilizers Cattle monoculture

5 Confined Animal Feeding Operations (CAFO) hh

6 More Industrial Agriculture Drawbacks Air & water pollution Fossil Fuel Use Erosion: soil exposed for long periods after harvest, over-grazed CAFOs produce enormous quantities of animal waste 1.4 billion tons in X human waste volume Manure produces methane & nitrous oxide (contribute to global warming) H 2 S gas causes illness, miscarriages

7 25 million gallons of waste spilled into N. Carolina s New River Manure Lagoons Killed 10 million fish Waste runs off into nearby creek Wastes flow into river or seeps into ground water

8 Problem w/ Synthetic Chemical Fertilizers Pesticides, Antibiotics, & hormones Salmon Farm

9 Synthetic Chemical Fertilizers Fertilizer replaces soil nutrients that plants use..but Don t replace soil s organic matter Crucial to proper soil chemistry for decomposers (nutrient cycling) Prevent compaction = water & air get to roots Use at wrong time of year (before rain), or too much fertilizer (plants can t use all) Water pollution, Eutrophication Cancer, blue baby syndrome, thyroid & immune disorders

10 Gulf of Mexico s Anoxic (Low Oxygen) Dead Zone 2000 flow (Drought) 1999 Dead zone = 20,000 km 2 (7,700 mi 2 ) Cause: Eutrophication - Fertilizer flowing into Gulf from farms in Mississippi River Basin

11 Synthetic Pesticides Control unwanted insects, fungus, weeds, pest-borne diseases (malaria) Chlorinated hydrocarbons (DDT) persist in environment (>30 years) Non-specific = kill more than target pest Death, nervous system, reproduction (feminization, intersex), cancer, egg shell thinning 1970 s Banned (Post-industrial nations) MANY still use (Malaria)

12 Fat soluble chemicals build up in tissues of organisms at higher trophic levels Biological Accumulation & Pesticides

13 Newer Synthetic Pesticides Non-persistent: decompose to CO 2, H 2 O BUT, more toxic to humans & vertebrates in close contact Disorders of immune, endocrine (hormone), & neurological (paralysis, memory loss) systems Birth defects, genetic mutations Cancer Asthma Malathion Diazinon

14 Pesticide Resistance Pesticide kills all that are susceptible (~95%) 5% of target pests are genetically resistant to the pesticide They will survive & reproduce = majority of breeding pop. Pass resistant genes on to offspring, so pesticide becomes less effective Within ~5 years 99% of pop. is resistant Farmers pesticide dosage & frequency

15 Antibiotics 70% of all US antibiotics given to healthy farm animals to prevent infections Infections spread in unsanitary & confined conditions on factory farms Create Antibiotic Resistant Bacteria Spread to humans & other animals Antibiotics effectiveness Must develop stronger antibiotics May no longer be effective for human medicine! Salmon Lice Mastisitis Infected udders

16 Hormones Given to dairy cows (1985): milk yield 14% Bovine Growth Hormone rbgh / rbst Pasteurization doesn t destroy Linked to breast, prostate, & colon cancer ( cell growth, metabolism), reproductive problems Banned: EU, Japan, Australia, NZ, Canada (EU bans USA dairy products) In all U.S. dairy unless organic or product states No rbst/rbgh None in imported EU cheese Now given to salmon, beef cattle, etc.

17 Crop Rotation: changing crops on same field (corn, oat, wheat, hay) Pests & disease Reduce use of pesticides Reduce erosion Increase profits Alternatives Polyculture: Grow 2 or > crops in same field & time Improve soil fertility Improve soil fertility (nitrogen-fixing legumes) Pests some plants naturally repel insects (marigolds) Better for wildlife

18 Polyculture Crop Rotation: Chickens follow cows in pasture

19 Organic Agriculture NO: chemical pesticides, fertilizers, sewage sludge, bioengineering, or ionizing radiation NO antibiotics or hormones, accommodate natural behaviors = cage free Government certifier inspects to ensure rules are followed Use compost & natural fertilizer (manure, bone & blood meal, worm castings) Pollution Precautions protecting livestock & worker health

20 Crop Rotation Polyculture hh Cage Free

21 Natural Predators Natural Pollinators Wildlife friendly deterrents

22 Promote Biodiversity Wildlife Buffers

23 Food for thought.. Large farms receive nearly twice as much in government subsidies as small, family farms hh