What converts free nitrogen to soil nitrogen?
If a small town with population 20,000 has a growth rate of 2%, how long will it take to double the population?
35 years (Rule of 70)
70/2 = 35
What zone of the ocean has the greatest biodiversity? Be specific.
No deduction for photic, but must say intertidal or neritic for points
What is a potential risk of genetically modifying one corn species to dominate production?
susceptible to blight (disease)
Why do developing nations use biomass over coal and other fossil fuels?
Cheaper to produce than to extract or import coal.
What nutrient is the most influential limiting factor for plant growth?
phosphorus (Stable insoluble compounds)
If 8000kcal/m2 are available for cows grazing grass, and the grasses respiration is 10,000kcal/m2, then how much energy was available from the sun per m2?
NPP - available to consumer
NPP + RES = Gross (the initial energy from the sun).
18,000kcal/m2
If an age structure diagram is wide at the bottom, what does that mean for the pooulation?
rapid growth
What type of species changes the population numbers of many species if removed?
keystone species
Not indicator (they decline first and signal problem).
What legislation could be used to protect the snow crab from overfishing in Russia?
CITES Convention on International Trade in Endangered Species and Wild Fauna and Flora
Explain how fossil fuels have disrupted the Carbon Cycle?
The are being burned into the atmosphere instead of being sequestered for millions of years.
If a Culpeper has a crude death rate of 5 per 1000, a crude birth rate of 8 per 1000, and a net immigration rate of 3 per thousand, then what is our county's growth rate (percent)?
(CBR +Im) - CDR = population per 1000; divide by 10 to get per 100 or percentage of population
3+8 - 5= 6 per 1000 or .6%
What decreases first during demographic transition?
death rate
Why are some pests resistant to pesticides?
evolution
What farming method can be used to reduce soil erosion in hilly areas?
contour plowing
Cover crop (technically)
What is the advantage of synthetic fertilizers over organic?
What is the advantage of organic over synthetic?
-builds soil structure and drainage.
If I have a string of ten 20 watt lights hanging on my patio and I leave the lights on for 6 hours a day, how many KwH of energy do I use a year?
10 x 20W x 6hours/day x 365day/1 year x 1kw/1000w = 438kwh
Explain the survivorship curve and reproduction type of a sunfish.
Type 3 (most eggs & fry eaten) and r strategist (many eggs at once)
What is the negative impact on genetic biodiversity of creating several small protected areas of forest?
Can isolate populations without corridors to connect and allow genetic drift.
On a farm with sandy soil and a thin layer of topsoil, what is the best irrigation method?
drip irrigation (slow over time since it will drain quickly in large amounts)
What process releases nitrogen into the air?
denitrification
If a car gets 20mpg and travels 100 miles per week, how many more gallons of gas per year would you have to use if you bought a SUV with 14mpg to drive?
I will do the math...
Explain the steps to demographic transition.
1- DR declines; population rises
2-BR slows but still pop rises
3- BR and DR levels, and pop begins to stabilize
4- Population stable
5- Decrease in population
Explain what a bottleneck is and how it impacts an ecosystem.
The loss of a large portion of a population results in few individuals to pass on genetics.
Explain the advantage of offshore wind over onshore wind energy production with respect to production.
There is more wind offshore (3 times more effective)