apes agriculture + water pollution

malnutrition

lacks correct balance of proteins, carbs, vitamins, and minerals

undernutrition

not enough calories

• global undernutrition → # of under nourishing declined but still greater than target

iron deficiency (aka anemia) symptoms + solutions

symptoms:

• anemia

• increased risk of death during childbirth

• infections

solutions:

• iron pills

• eat more red meat

Vitamin A (aka beta carotene) deficiency symptoms + solutions

symptoms:

• childhood blindness

• increased risk of infection

solutions:

• golden rice

• supplements

• dairy

• greens

iodine deficiency symptoms + solutions

symptoms:

• goiter (swelling of thyroid gland)

• stunted growth

• impaired mental capabilities

solutions:

• iodized salt

• seafood

agriculture → grains

• largest part of our diet

• 60% of human energy intake is from corn, rice, + wheat

industrial agriculture

applies techniques of mechanization + standardization

• aka agribusiness

energy subsidy

fossil fuel + human energy input per calorie of food produced

• most in the form of fossil fuels + transportation

The Green Revolution

new management techniques, fertilization, irrigation, + improved crop varieties → shift in agricultural practices

mechanization

reliance on large machinery and fossil fuels

• improved efficiency + higher production

• drawbacks: air pollution, non-sustainability, soil compaction

soil compaction

machines drive over farmland → squishes soil down + reduces size of pores

consequences:

• can’t support microorganisms

• water can’t infiltrate soil + drain quickly

• roots cannot push through

solution: aerate soil

waterlogging

water infiltrates soil + cannot drain → impedes plant growth

salinization

soil degradation that occurs when small amounts of salt in irrigation water becomes highly concentrated on soil surface through evaporation

organic fertilizers

composed of organic matter from plants + animals

examples:

• animal manure

• green manure (freshly cut green vegetation)

• compost

pros:

• probably free

• supports soil microbes

• contains all nutrients

cons:

• slow release of nutrients

• may contain weeds (green)

• may contain pathogens (manure)

• may contain salt (compost)

inorganic/synthetic fertilizer

produced commercially, normally with the use of fossil fuels

• provides nitrogen (N), phosphorous (P), potassium (K)

pros:

• greatly increases production

cons:

• no trace nutrients

• doesn’t support soil organisms

• runoff into bodies of water

• made from nonrenewable resources

• release GHG + NOx

desertification

damage to soil (compaction, salinization, waterlogging, etc.) → turns fertile areas into deserts

• more common in places right next to deserts

• generally irreversible → land sometimes used for nomadic grazing

consequences (mostly for humans):

• loss of food production

• famine

• environmental refugees

Genetically Modified Organisms (GMOs)

pros:

• greater yield

• greater food quality

• reductions in pesticides use

• pest/pesticide resistance

cons:

• limited restrictions (in US)

• safety for human consumption

• effects on biodiversity of crops → fragile food supply

furrow irrigation

process: farmers dig a trench + fill with water

pros:

• cheap + easy

cons:

• water loss

• increased erosion

flood irrigation

process: flood field and let water soak in

pros: cheap and easy

cons: may damage plant growth, lots of water loss, increased methane production (inc. decomposition rates)

spray irrigation

process: water pumped to nozzles that spray water across field

pros: more efficient choice

cons: expensive, requires energy, water is lost (mostly through evaporation)

drip irrigation

process: hoses with small pores laid near roots/buried below soil

pros: ~100% efficient + less weeds

cons: expensive + doesn’t work for short growing crops because it takes energy to take them out and put back up every season

consequences of irrigation

• waterlogging

• soil salinization

• soil erosion (repeated tilling and planting)

how to prevent soil erosion

• contour planting

• no-till agriculture

monocropping

mostly done — planting only one crop

• financially beneficial

consequences:

• reduced biodiversity

• repeated same treatments to soil with potential depletion of nutrients and damage to helpful bacteria

• increased risk of pests

• increased risk of crop diseases

pesticide

kills pests

herbicide

kills weeds

insecticide

kills insects

broad-spectrum pesticide

kills many kinds of pests

selective pesticides

targets narrow range of organisms

persistent pesticides

remains in environment for a long time

pesticide treadmill

over time, pest populations evolve resistance to pesticides, which requires farmers to use higher doses/develop new pesticides

• negative feedback loop

pesticide resistance

a trait possessed by certain individuals that are exposed to pesticides and survive

integrated pest management (IPM)

agricultural practice that uses a variety of techniques designed to minimize pesticide impacts

• crop rotation

• intercropping

• pest-resistant crop varieties

• creating habitats for predators

• limited use of pesticides

sustainable agriculture

growing enough food but not depleting resources

intercropping

2 or more crops planted at the same time in the same field to promote a synergistic interaction

crop rotation

crop species in a field are rotated from season to season

agroforesting

trees and vegetables are intercropped

organic agriculture

production of crops without use of pesticides/synthetic fertilizers

principles:

• keep as organic matter and nutrients in soil + on farm

• avoid use of synthetic fertilizers and pesticides

• maintain soil by increasing soil mass, biological activity, etc

Concentrated Animal Feedlot Organizations (CAFO)

animals concentrated in an enclosed area and fed grain/fish meal

pros:

• efficient and cheap → less land, overgrazing, and erosion

cons:

• large inputs of grain, water, and fossil fuels

feedlot concerns

• efficiency → 70% of corn + 80% soybeans grown go to feeding livestock; more efficient to feed humans with grains directly (10% rule)

• antibiotic + growth hormone use → may lead to antibiotic resistance + hormones may pass to humans

• methane → cows burp 16% of methane release

• waste → only 50% of waste returned to soil as fertilizer; runoff leads to eutrophication + drinking water contamination

free-range farms

animals roam around mostly untended land + graze

pros:

• less environmental impact; considered more sustainable

cons:

• uses lots of land → less meat, overgrazing, threats from predators, increased erosion

fishery

a commercially harvestable population of fish within a particular ecological region

fishery collapse

decline of fish population by 90% or more

bycatch

unintentional catch of nontarget species while fishing

individual transferable quotas (ITQ)

a fishery management program in which individual fishers are given a total allowable catch of fish in a season that they can either catch or sell

aquaculture

raising marine/freshwater fish in ponds/underwater cages (~feedlot for fish)

pros:

• efficient → less water/space = more fish

• takes pressure off wild species

cons:

• need lots of land, feed, and water

• lots of waste

• may destroy estuaries and wetlands

• dense populations increase disease → increased use of antibiotics and risk to wild populations

septic tanks

• typically in rural areas

• way to manage wastewater

• requires a lot of land

• run by gravity

wastewater treatment process (steps + what happens in them)

1. Primary → remove solids

• screens → settling basin → liquid continues to secondary

2. Secondary → break down biological oxygen demanding waste (BOD)

• aeration basin → bubble air into affluent + bacteria break it down

3. Tertiary → kill pathogens

• chlorine, UV light, O3 bubbles

• then tested

problems with waste water treatment

• open loop → unsustainable → better options = pumping water back into groundwater/sending directly to drinking water treatment plant

• no treatment for stom water

• not removed in waste water treatment: pharmaceuticals, heavy metals, organic compounds (VOCs), phosphates

Clean Water Act 1977

• amendment to Federal Water Pollution Control Act of 1972

• set basic structure for regulating discharge of pollutants in US

• designed to protect fishing, swimming, + ecosystem health

• set up National Pollutant Discharge Elimination System (NPDES) → regulates point sources (not runoff)

• Total Maximum Daily Load (TMDL) → sets cap for amount of pollutant discharge

Safe Drinking Water Act

established drinking water standards

• focuses on all water actually/potentially designed for drinking use

• sets Maximum Containment Levels (MCLs) for drinking water

• pathogen dose = 0 always

point source

1 simple, easy to identify source

• eg. pipe from power plant dumping hot water

non-point source

pollution that comes from a variety of place

• eg. runoff, exhaust, AMD

Nutrients

• sources: agricultural runoff from fertilizer/feedlots, detergent, disturbed soil

• impacts: eutrophication → dead zones

• indicators: elevated N + P levels, lower dissolved oxygen levels, algal blooms (increase in organic matter)

• reduction: runoff reduction (repair riparian zone), treat stormwater, improve farming techniques, use organic fertilizer, avoid detergent with phosphates

eutrophication

organic matter (aka BOD)

• sources: agricultural runoff, sewage, papermills, food processing

• effects: high temperatures reduce amount of oxygen water can hold + warm water

• indicators: increased water temperature, decreased DO, fish kills

• reduction: reduce runoff, cool water temperatures before releasing, maintain water flow + riparian zone (provides shade)

sediment pollution

• sources: erosion, mining, construction

• effects: blocks sunlight, may choke fish, increased water temperature and turbidity

• indicators: increased turbidity, increased temperature

• reduction: maintain soil and reduce erosion

pathogen pollution

• sources: human + animal waste → raw sewage + CAFO runoff

• effects: diseases → cholera, typhoid, giardia, e. coli

• → symptoms of diseases: vomiting and diarrhea

• indicators: presence of fecal coliform bacteria

• reduction: treat sewage, boil water, separate drinking & waste water, use filters for parasites

endocrine disruptors pollution

• sources: CAFOs from added hormones & pesticides that mimic hormones

• effects: interfere with functioning of the endocrine system, even in very low doses

• indicators: (all in fish, amphibians, and reptiles) low sperm counts, hermaphroditism, decreased production of testosterone

• reduction: decrease use of hormones in raising animals and reduce use of chemicals that mimic hormones

persistent organic pollutants (POPs)

• non-polar and fat soluble

• stay in environment + ecosystems for a long time

• biomagnify and bioaccumulate

• eg. DDT & PCB

oil spills

sources:

• natural oil seeps

• surface runoff

• transport and extraction

indicators:

• presence of oil byproducts → benzene, xylene, & other hydrocarbons

• kill wildlife direct + indirectly

reduction:

• improve safety standards for extracting and transporting oil

• research oil spill cleanup techniques

oil spill cleanup methods

• containment boom + vacuum

• containment boom + absorb

• dispersant

• GMO bacteria → breaks down oil

plastic + solids pollution

sources:

• improper waste disposal

• incidental waste falling into waterways

indicators:

• microplastics

problems:

• wildlife eats plastic + microplastics, mistaking for food

• toxins in plastics can make its way into food supply

reduction:

• reduce reuse recycle

• no remediation

groundwater pollution

sources:

• underground storage tanks

• older unlined landfills

• modern landfill leaks

effects:

• aquifer contamination

• plume movement into surface water (at springs)

reduction:

• line landfills + manure lagoons

• bury waste in appropriate hazardous waste facilities

• clean up superfund + brownfield sites

• replace underground storage tanks

heavy metal pollution

sources:

• natural deposits (arsenic, mercury)

• mining

• coal burning (mercury)

• e-waste (cadmium, mercury, lead)

• industrial processes - smelting

effects:

• bioaccumulate + biomagnify

• largest impact at the top of food chain

• most toxic @ low doses + neurotoxins

indicators:

• positive tests for metals

reduction:

• minimize output of waste

temperature testing

desired range: varies, but range of tolerance for native species

impacted by:

• stream flow + lake depth

• thermal pollution from power plants

• turbidity level

pH testing

what is measured: concentration of H+ ions → how acidic/basic

how to measure: pH probe/litmus paper

desired range: b/w 5-8

impacted by:

• acid rain

• AMD

• buffering capacity

• geology of the watershed (limestone)

nitrate testing

what is measured: ppm of nitrate ions → indicated how nutrients rich

how to measure: digital probe/nitrate titration kid

impacted by:

• agricultural runoff

• fertilizer

• feedlots

• sewage treatment plants

phosphate testing

what is measured: ppm of phosphate ions

how to measure: probe/titration kit

impacted by:

• runoff

• detergents

dissolved oxygen (DO)

measured by: ppm of oxygen dissolved

impacted by:

• temperature

• nutrient levels

• turbidity

• organic waste

biological oxygen demand (BOD)

what is measured: rate of oxygen use over 5 days

desired range:

• pristine rivers: <1mg/L

• polluted rivers: 2mg/L-8mg/L

• sewage effluent: >20mg/L

impacted by: