What is our atmosphere predominately made up of?
Nitrogen (N2) gas (78.08%)
Ecosystem contain biotic and abiotic components. Name 2 components of each category.
Biotic- anything living (plants, animals, fungi, microorganisms)
Abiotic- minerals, climate, soil particles, rocks, landforms, sunlight
What are the 5 soil horizons in the soil profile?
O, A, B, C, R
What is the difference between a continuous cropping system and a crop rotation?
continuous- same crop planted over many years
crop rotation- planned sequence of different crops planted over years on the same field
What is sustainable agriculture?
The accountable and profitable production of food, fiber, or energy to meet societal needs while maintaining soil, water, and air resources for future generations.
What are some practices that farmers can engage in to manage soil temperature and moisture?
management of crop residues (conservation tillage, no-till, mulch), fallowing, cover crop
Describe the flow of energy in a food chain
Food chains reflect the flow of energy and nutrients. Every food chain begins with the sun, which fuels the primary producers (grasses), who are eaten by primary consumers (rabbit), who are eaten by secondary consumers (wolf), who eventually die and are decomposed by microorganisms.
Define soil texture
Texture defines a soil's fineness or coarseness and is determined by the type and proportional amount of sand, silt, and clay.
How are perennial legumes such as alfalfa effective in crop rotations?
Legumes fix nitrogen that is put back into the soil for subsequent crops
What are some advantages of cover crops? Name two potential cover crop species.
1. Protect soil from erosion
2. Absorbs excess fertilizer nutrients from soil
3. reduce weed growth
4. provide habitat for wildlife that consumes weed seeds
5. controls soil moisture/temperature levels
6. enhances soil fertility (legumes)
Examples: winter rye, hairy vetch, crimson clover, berseem clover, buckwheat, forage/oilseed radish
What are the 4 layers of the atmosphere, and how do the first two layers influence human and plant life?
Troposphere, Stratosphere, Mesosphere, Thermosphere
Troposphere- contains gases essential for life, zone where weather occurs
Stratosphere- contains ozone which absorbs harmful UV radiation
What is an ecological pyramid and how does it differ from a food chain?
An ecological pyramid shows the transfer of energy and biomass from producers to consumers. At each successive higher level of the pyramid, less energy (((10%))) is transferred.
What is cation exchange capacity? Is a high CEC good?
The amount of exchangeable cations (+) a soil (-) can attract and sustain. Yes, a high CEC indicates that a soil can hold nutrients well instead of allowing them to leach through the profile.
What advantages do polycultures have over monocultures?
-greater tolerance to environmental and pest stress
-insurane against total crop failure (yield stability)
-income diversification
-maximize resources/ greater productivity per acre
What is the difference between Strip Cropping and a Living Mulch?
Strip Cropping/Contour Strip Cropping: growing crops in monocultures in adjacent strips planted within a field
Living Mulch: planting annual grain crops into a living, but suppressed, perennial sod that will recover after harvest
Describe the THREE components of light that influence plant growth.
Light quality: wavelengths of sunlight
Light Intensity: quantity or brightness of light
Light Duration: photoperiodism/ changing lengths of day and night
What are the three pathways that fix atmospheric nitrogen into a stable and plant-usable form?
Biological Fixation (N2 -> NH4)
Atmospheric Fixation (N2 -> NO3-)
Industrial Fixation (N2 -> NH3)
Plants take up NO3- or NH4
Name 2 types of fertilizer application methods.
Broadcast, Injection, Banding, Popup fertilizers, side-dressing, fertigation
Define Agroforestry and name two strategies
Agroforestry: trees or shrubs are grown for harvest alongside crops
Silvopasture: Combines trees with livestock pastures
Alley cropping: trees are grown in rows with crops grown in between the trees
Name the five climactic regions of the Koppen System.
Type A: moist tropical
Type B: dry climates
Type C: moist climates with mild winters
Type D: moist climates with severe winters
Type E: polar climates
Identify and describe 2 irrigation strategies
Surface irrigation (gravity flow irrigation): applies water directly to the soil surface via flood/furrow irrigation
Sprinkler irrigation (center pivot, linear irrigation): applies pressurized water through the air by using pipe and elevated sprinklers
Subsurface irrigation or Drip Irrigation: most efficient and delivers water directly to plant roots
Compare and contrast natural ecosystems with agroecosystems
Agroecosystems: high management, high inputs, high breeding, low diversity
Natural Ecosystems: high diversity, low inputs, low management, low breeding
Develop a nutrient management plan for a 50 acre field of corn that is less than a 0.5 mile from a riverbed.
1. time fertilizer according to crop needs and not in excess to avoid nutrient runoff
2. incorporate perennial cover crops into rotations
3. reduce soil erosion
4. Test soil occasionally to avoid overapplication of nutrients
What is the purpose of the Conservation Reserve Program and how many acres are enrolled in its program?
1. Provides assistance to farmers in complying with federal, state, and tribal environmental laws and encourages environmental enhancement.
2. Encourages farmers to convert highly erodible cropland to vegetative cover for an annual stipend.
3. 36 million acres enrolled in CRP
4. Reduces soil erosion, protect food/fiber resources, reduces sedimentation, improves water quality, establishes wildlife habitat, etc.
Name all the macronutrients essential for plant growth
CHOPKiNS CaMg
Carbon, Hydrogen, Oxygen, Phosphorus, Potassium, Nitrogen, Sulfur, Calcium, Magnesium