As you travel from the O-horizon to the C-horizon the levels of nutrients in the soil... (increase or decrease)
decrease
The practice of planting crops with the shape of a hillside, resulting in reduced soil erosion and increased water retention
CAFO stands for this
Concentrated Animal Feedlot Operation
This biogeochemical cycle does not have an atmospheric component
Phosphorous
How do irrigation practices lead to salinization?
salts are left behind after irrigated water evaporates, saltwater intrusion in coastal areas can also contribute
As you travel from the O-horizon to the C-horizon the soil becomes _(more or less)__ like the parent material...
more
Adding nutrients, erosion control, attracting pollinators
This is one major downsides of overuse of pesticides in agriculture
Pesticide resistance, harming non-target species, EDCs in our food
Humans are currently altering the carbon cycle through these practices
Deforestation, fossil fuel extraction, burning fossil fuels
Which irrigation method has the smallest negative impact on water use and erosion?
drip irrigation
Which soil texture likely has the highest percolation rate?
Sand
Two disadvantages in the practice of monoculture include these
decreased genetic diversity, increased risk of disease/pests, soil degradation, poor pollinator health
Livestock operations are less efficient than farming traditional crops because they use more of this.
Land
What are 2 sinks/reservoirs of water in the hydrological cycle (other than the ocean)
groundwater, rivers, lakes, polar ice caps, glaciers
Which substance has the highest toxicity?
Paclitaxel
What soil texture is a sample with 40% silt, 30% sand and 30% clay
Clay loam
This practice involves burning down areas of forest and using using the resulting ash to enrich the soil. This is common in tropical regions.
Slash-and-burn
One major downside of CAFOs would be this
antibiotic overuse (which leads to resistance), increased greenhouse gas emissions, increased grain prices, disease spread, eutrophication (from waste)
Livestock practices impact the carbon cycle by the release of these two carbon based compounds
CO2 and CH4 (methane)
The germination rate of radish seeds in the presence different concentrations of salt was studied. 600 seeds were planted in the study.
After 3 days, the 3% concentration had 500 germinated seeds, the 4% concentration had 450 germinated seeds, the 5% concentration had 376 germinated seeds, the 6% concentration had 300 germinated seeds and the 7% concentration had 225 germinated seeds. What is the LC50?
6% the concentration that killed 50% of the population (300/600)
Top-soil. Contains: Humus, minerals, worms, microbes
Erosion is harmful to agricultural land because it removes nutrient rich topsoil. Two practices that reduce soil erosion include...
windbreaks, crop rotation, cover crops
An example of a cultural control for integrated pest management would be this.
strip cropping, crop rotation, changing irrigation methods, changing planting time
Humans are currently altering the phosphorous and nitrogen cycles through the use of what?
What is one disadvantage of this practice?
fertilizers. disadvantage: pollution (water and soil), eutrophication, lowered soil quality over time, cost
This central U.S. aquifer is being depleted by agricultural practices that draw water faster than it can be recharged
Ogallala Aquifer