Constructing a pyramid of biomass reportt

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Introduction

A food chain is a sequence of organisms, each of which feeds on a type of organism from the preceding trophic level. However, food chains do not give an accurate picture of the complex feeding relations that exist between each trophic level. So, to have a better understanding of these feeding relations ecological pyramids are used - for example, pyramids of biomass. A pyramid of biomass shows the relationship between biomass and trophic levels by quantifying the amount of biomass present at each trophic level. The percentage of usable energy transferred as biomass from one trophic level to another level is called ecological efficiency and it is typically of 10% i.e. 90% of biomass is lost through not all of the organism being eaten, faeces and through respiration.

To study and analyse the relation between biomass and trophic levels i.e. of ecological efficiency and to construct a pyramid of biomass, a small area in a clearing in St.Julian's school's wooded area was investigated.

Hypothesis

I expected to obtain a normal upright pyramid of biomass, as biomass decreases at each trophic level. This occurs because the transfer of energy from the producers to the primary