Which of the following statements is not correct ?

Ecological pyramids illustrate how energy, number of individuals, and biomass change across trophic levels.

1. Energy pyramid: Energy is greatest at the producer level and decreases at each higher trophic level due to metabolic losses. Thus the energy pyramid is always upright.

2. Pyramid of numbers in a grassland: Grasslands typically contain many small plants (producers) and fewer herbivores and carnivores, making the number pyramid upright.

3. Pyramid of biomass in marine ecosystems: In the ocean, primary producers (phytoplankton) are tiny and have relatively low total biomass, whereas consumers such as zooplankton and fish often accumulate more mass. This leads to an inverted biomass pyramid, with larger biomass at higher trophic levels.

Since the biomass pyramid in the sea is generally inverted, the statement “Pyramid of biomass in sea is generally upright.” is false. Therefore, this statement is the one that is not correct.