Why are there always more members on the lower trophic levels than the higher trophic levels?
as energy moves from one trophic level to the next more and more energy is available for the next level limiting the number on the
next level
the members of the lower trophic levels are always small in size so there con be more of them
as energy moves from one trophic level to the next, less and less energy is available for the nent level limiting the number on the
next level.
the members of the lower trophic levels pass on all of their energy to the next trophic level

This question is mainly related to diversity and evolution. Lower trophic levels means simple organisms in which evolution happened faster than the bigger trophic level organisms.  

Explanation:

In principle, faster evolution means more rapid change in genetic material. Therefore, simple organisms respond quickly to the changes in environment and they have more chances of going into separate lineage whereas in higher organisms it gets difficult. This is the reason that we have more diversity in smaller organisms as compared to the larger organisms.

the calvin cycle has three stages. in stage 1, the enzyme rubisco incorporates carbon dioxide into an organic molecule. in stage 2, the organic molecule is reduced. in stage 3, rubp, the molecule that starts the cycle, is regenerated so that the cycle can continue