Final answer:
Energy is less efficiently transferred to higher trophic levels. In ecological pyramids, producers have the most energy, decreasing upwards. Biomass pyramids vary in shape based on ecosystem productivity and organism turnover rates.
Step-by-step explanation:
In an ecological pyramid, producers form the base with a certain amount of energy – in this case, 1,000,000 kilocalories. The energy available to primary consumers will be significantly less due to the efficiency of energy transfer through trophic levels. This is often quantified by the ten percent law, indicating that typically only about 10% of the energy at one trophic level is transferred to the next level.
Trophic levels within ecosystems illustrate the flow of energy and biomass. As we move up the trophic levels, from producers to primary consumers, and so on, the amount of biomass decreases. This is because energy is lost at each level due to metabolic processes, and thus less is converted into biomass. Energy pyramids are always upright, emphasizing that energy diminishes with each ascending level. In contrast, biomass pyramids can be upright, inverted or even diamond-shaped, depending on the ecosystem and the productivity of the organisms at each level.
The measure of primary productivity is critical as it denotes the creation of organic compounds from atmospheric or aquatic carbon dioxide. It primarily occurs through photosynthesis, impacting the biomass at each subsequent level. For example, in the English Channel ecosystem, the primary producers, which have lower biomass, support primary consumers with a higher biomass due to their rapid reproduction and turnover rates.