APES Unit 5 - Agriculture Flashcards
Ecological Footprint
measure of how much a person/group consumers, expressed in an area of land
carbon footprint
measured in tons of CO2 produced per year (material goods, food production, energy use)
sustainability
consuming a resource or using a space in a way that does not deplete or degrade it for future generations (using compost over synthetic fertilizer)
maximum sustainable yield
the maximum amount of a renewable resource that can be harvested without reducing or depleting the resource for future use
Biodiversity Indicator of sustainability
genetic, species, and ecosystem (high Biodiversity=healthier ecosystems, low Biodiversity=pollution, habitat destruction, climate change)
food production indicator of sustainability
indicates ability of earth’s soil, water, climate (major threats to food production=climate change, soil degradation, groundwater depletion
CAFO
concentrated animal feed operations
Manure Lagoons
large, open storage pits for animals waste (waste contains: ammonia (N), hormones, antibiotics, fecal coliform bacteria (heavy rain can flood lagoons and contaminate nearby surface and ground water with runoff
Free Range Grazing
Animals (usually cows) graze on grass and grow at a natural rate without growth hormones
positives of free range grazing
no need for antibiotics, doesn’t require production of corn to feed animals, water is dispersed over land naturally, animals can graze on land too dry for most crop growth
negatives of free range grazing
requires more land/meat, more expensive
overgrazing
too many animals grazing an area of land can remove all the vegetation which leads to topsoil erosion, animals also compact soil, decreasing H2O holding capacity
desertification
can occur if plants are killed by overgrazing and soil is compacted so much that it can’t hold enough water anymore
inefficiency of meat
producing meat for humans to eat is far less efficient than producing plants in terms of energy, land and water use
energy used for meat production
energy needed to bring water to animals, energy needed to house animals, energy needed to slaughter and package
land used for meat production
all of the energy needed to grow plants to feed animals plus room the animals take up
water used for meat production
all of the water for crops that animals eat plus the water the animals drink
Industrialized agriculture
uses large amounts of fuel energy, water, commerical fertilizers and pesticides, frequently grow wheat and cotton, harvest can be obtained easily and efficiently
problems with Industrialized agriculture
soil erosion, crops become more vulnerable to attack by pests
Plantation agriculture
mostly for sale in developed countries - produces increased yield but decreases biodiversity
high input monoculture types
Industrialized agriculture, and plantation agriculture
traditional agriculture
low input polyculture
traditional subsistence agriculture
human labor to produce only enough crops or livestock for a family’s survival
traditional intensive agriculture
increase inputs of labor, fertilizer and water to obtain a higher yield - feed family and sell, most grow several types of crops on the same cleared plots, recent studies have shown that low-input usually produces high yields
tilling
mixing and breaking up soil to make planting easier (loosens soil for roots), increases erosion by loosening topsoil, breaking up leftover root structure from harvest, loss of organic matter and topsoil nutrients over time
slash and burn
cutting down vegetation and burning it to clear land for agriculture and return nutrients in plants to soil
furrow irrigation
easy and inexpensive; dig trenches along the crop rows and fill them with water
flood irrigation
flooding an entire field with water, generally more disruptive but relatively efficient
spray irrigation
more expensive and uses a fair amount of energy; water is pumped from a well into an apparatus that contains spray nozzles which spray water across the field
drip irrigation
uses a slowly dripping hose that is either laid on the ground or buried beneath the soil
negative consequences of irrigation
can deplete groundwater, promotes saltwater intrusion into freshwater wells, waterlogging, salinization
waterlogging
soil remains under water for prolonged periods of times
salinization
small amounts of salts in irrigation water become concentrated
industrial human water use
power plants, metal/plastic manufactoring
municipal human water use
households (toilet, shower, drinking water)
agriculture human water use
water for livestock, irrigation water for crops
Groundwater
H2O stored in pore space of permeable rock and sediment layers
aquifers
useable groundwater deposits for humans
unconfined aquifers
recharge quickly
confined aquifers
recharge are longer-term water deposits that recharge more slowly
saltwater intrusion
excessive pumping near coast lowers water table pressure, allowing saltwater to seep into groundwater
cone of depression
forms when water table is lowered by excessive pumping, depleting water and drying nearby wells
fertilizers
contains essential nutrients for plants - N, P, K
organic fertilizers
composed of organic matter from plants and animals; usually animal manure, contains microorganisms that break down soil and improve structure over time, slow release of nutrients allows for roots systems to be created, ultimately increases tolerance to drought and stress and reduces plant disease
drawback of organic fertilizers
process is slow
synthetic fertlizers
produced commercially; highly concentrated; widespread use has increased crop yields, designed for easy application, accelerated results: quick release of nutrients, processes of manufactoring uses fossil fuels, more likely to be carried away by nutrient runoff due to over usage, do not add organic matter to the soil since there are no microorganisms present
pesticides
natural or synthetic substance that kills or controls organisms that people consider pests, due to increased pest populations that are encouraged by mono-cropping pesticide use has become routine
insecticides
target species of insects and other invertebrates that consumer crops
herbicide
target plant species that compete with crops - makes agriculture more efficient
genetic engineering
scientists engineered seeds for plants that could withstand the spraying of the herbicide glyphosate, allowing farmers to spray over growing corn while killing weeds
drawbacks of genetic engineering
some pesticides are persistent - remain in the environment for a long time, non-persistent, pest populations may evolve resistance to pesticides, pesticides can also kill organisms that benefit farmers, can runoff into surrounding surface waters
integrated pest management (IPM)
an effective and environmentally sensitive approach to pest management
goal of IPM
manage pest damage by the most economical means, and with the least possible hazard to people, property, and the environment
biocontrol
introducing a natural predator, parasite, or competitor to control the pest populations, purchasing and spreading the control organisms in fields, or building homes for them/planting habitats they need to attract them naturally
crop rotation
many pests prefer one specific crop or crop family, rotating crops can prevent pests from becoming established since it disrupts their preferred food choice, disrupts weed growth
intercropping (push-pull system)
“push” plants emit volatile chemicals that naturally repel pests away from crop
“pull” plants emit chemicals that attract moths to lay eggs in them, instead of crop
Benefits of IPM
reduces deaths and mutation of non-target species, reduces effects on humans consumers of produce, reduces contamination of surface and ground water by agricultural runoff with pesticides
negatives of IPM
many pesticides are carcinogens (cause cancer), can be more time consuming and costly than just crop dusting pesticides
soil erosion
wind and water, includes a breakdown, detachment, transport or redistribution of soil particles
topsoil
renewable resource but it is a slow process-when topsoil is eroded faster that it can be replaced it becomes nonrenewable
desertification
causes: overgrazing, erosion, salinization, soil compaction, natural climate change
cover methods: mulching
bare soil between growing plants is covered with a layer of organic matter such as straw, grasses, leaves, and rice husks - anything readily available
cover crops
cover methods: over crops are a kind of living mulch. They are plants (legumes) which are grown to cover the soil, also reducing weeds
green manures
cover method: also usually legumes - are planted specifically to improve soil fertility by returning fresh leafy material to the soil
mixed crop and intercropping
cover method: planting alternating steps of a row crop and another that covers the soil
crop residues
cover method: after harvest, unless the next crop is to be immediately replanted, it is a good idea to leave the stalks, stems and leaves of the crop just harvested, lying on the soil
agroforestry
cover method: planting trees among agricultural crops helps us to protect the soil from erosion, particularly after crops are harvested
minimum cultivation
cover method: each time the soil is dug or plowed, it is exposed to erosion. In some soils it may be possible to show crops without plowing or digging, ideally among the crop residue from the previous crop
man-made terraces
barrier method: grow food on step slopes - don’t deplete topsoil
contour plowing
barrier method: whenever possible all land should be plowed along the contour line - never up and down, since this simply encourages erosion
contour barriers
almost any available material can be used to build barriers along the contours
natural terraces
barrier method
early planting
cover method
crop rotation
replanting some crops continuously depletes soil of the same nutrients, can allow soil to recover from nitrogen demanding crops
limestone
releases calcium carbonate - neutralizes acidic soil, acidic soil makes toxic metals more soluble in soil
hydroponics
growing crops in a medium other than soil, can be grown using liquid, sand, or gravel
aquaponics
sustainable food production system that combines a traditional aquaculture with hydroponics - in a symbiotic environment
aeroponics
growing plants in a moist environment, suspends the plant in a somewhat closed environment and water is sprayed with a nutrient-rich water
ways to improve soil fertility
crop rotation, limestone, hydroponics, aquaponics, aeroponics
organic food
has been grown or raised without chemical fertilizer, pesticides, weed killers, or drugs
organic
no toxic or persistent pesticides, no synthetic grown hormones, no cloning, no petroleum based fertilizers, no artificial colors or flavors, no GMOs, no artificial preservatives, no irradiated products
natural
no artificial flavors or colors, no artificial preservatives, no irradiated products, no GMOs
FDA
Food and Drug Administration: protects public health by ensuring food is safe to eat
herbicide
used to kill undesirable plants or “weeds”
GMO
Genetically Modified Organism: produced through any type of genetic modification whether by high-tech modern genetic engineering OR long time traditional plant breeding methods
Genetic Engineering
on the other hand, can create plants which incorporate genes directly into an organism
advantages of GMOs
pest resistance, herbicide tolerance, disease tolerance, cold tolerance, drought tolerance/salinity tolerance, nutrition
disadvantages of GMOs
unintended harm to other organisms, reduced effectiveness of pesticides, cross-breading, unknown effects on humans health, loss of variety, decreased nutritional value and potential allergic responses, damage to biodiversity
