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A boreal forest has a GPP of 252 g/m2/year. The forest uses 112 g/m2/year in cellular respiration. One food chain consists of Trees -> Deer -> Wolverines. An adult wolverine weighs about 15 kg.

A. calculate the NPP of the forest.
B. Create a biomass pyramid.
C. Determine the area needed to support 5 wolverines per year.

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Answer:

A. The NPP of the forest is the difference between the GPP and the respiration, so it can be calculated as follows:

NPP = GPP - respiration NPP = 252 - 112 NPP = 140 g/m2/year

B. A biomass pyramid shows the amount of biomass at each trophic level in an ecosystem. To create a biomass pyramid, we need to estimate the biomass of each organism and multiply it by the number of individuals in each trophic level. We also need to assume a 10% efficiency of energy transfer between trophic levels, meaning that only 10% of the biomass at one level is available to the next level. Here is an example of a biomass pyramid for the given food chain:Trophic level Organism Biomass (g/m2/year)

Tertiary consumer Wolverine 0.14

Secondary consumer Deer 1.4

Primary producer Tree 140C. To determine the area needed to support 5 wolverines per year, we need to estimate the biomass demand of a wolverine and divide it by the biomass supply of the tertiary consumer level. We can use the following formula:

Area = (Biomass demand x Number of wolverines) / Biomass supply

We can assume that a wolverine needs about 10% of its body weight in food per day, which means that a 15 kg wolverine needs about 1.5 kg or 1500 g of food per day. To convert this to a yearly basis, we multiply by 365 days, which gives us 547500 g or 547.5 kg of food per year for one wolverine.

The biomass supply of the tertiary consumer level is the biomass of the wolverine trophic level, which is 0.14 g/m2/year according to the biomass pyramid.

Plugging these values into the formula, we get:

Area = (547500 x 5) / 0.14 Area = 19553571.43 m2

To convert this to km2, we divide by 1000000, which gives us:

Area = 19.55 km2

Therefore, the area needed to support 5 wolverines per year is about 19.55 km2.

Step-by-step explanation:

User Anthony Blackshaw
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