Concept explainers
Figure 46.8 Why do you think the value for gross productivity of the primary producers is the same as the value for totall heat and respiration (20,810 kcal/ m2/yr)?
To analyze:
The value for gross productivity of producers is the same as the amount for total heat and respiration (20,810 kcal/ m 2/yr)?
Introduction:
In an ecosystem, the productivity can be determined by the percentage of energy entering into the ecosystem and gets assimilated into biomass in a specific trophic level. Gross primary productivity embraces the rate of photosynthesis plus the organic matter used up in respiration during the measurement period.
Explanation of Solution
The one-way flow of energy is a universal phenomenon of nature and is the result of the operation of the law of thermodynamics which are fundamental concepts of physics. The first law of thermodynamics states that energy can neither be created nor destroyed. According to the first law light energy of the ecosystem is converted into potential energy of the food by producers. The values of gross primary productivity and total respiration and heat are the same because of this law. Eventually, all energy consumed by living systems is lost as heat or used for respiration, and the total energy output of the system must equal the energy that went into it.
As energy follows the first law of thermodynamics, also known as the law of conservation hence both values require to be the same. Energy may transform from one form to another but will never be destroyed.
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- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax