Question

Consider a self-sustaining ecosystem consisting of three components X, Y and Z set up in a laboratory for several weeks. During a 26-day observation period, it was disturbed by human intervention on a particular day. The population size of the three components during this period is tabulated below.

(A) Assign the correct component alphabet to each of the following:

(i) Primary producer ____ 

(ii) Herbivore ____ 

(iii) Carnivore ____

(B) The average biomass of a producer is 0.0060 g and that of a herbivore is 0.0025 g. Using the population sizes on day 1, calculate the transfer of energy in the form of biomass(in %) from producers to herbivores occurring in the ecosystem

Show your calculation in the box

Answer: _______

(C) Indicate the day and the most likely activity that has disturbed the balance of ecosystem

Answer: Day _____

Activity: _______

Option for activity:

(a) Removal of component X.

(b) Addition of component Y.

(c) Partial removal of component Z.

Answer 1

(A) (i) Z

(ii) Y

(iii) X

(B) The average biomass of producer = 0.0060 gm

Using population size on day 1 = 200

= 0.0060 gm x 200 = 1.2

The average biomass of herbivores = 0.0025 g

Using population size on day 1 = 40

= 0.0025 x 40 = .1

The transfer of energy in the form of biomass from producer to consumer is

1.2 x X/100 = 0.1

x = 8.33%

(C) The day which has most likely disturbing the balance of ecosystem is day 17. Activity responsible is a (removal of component X)