Which of the following best explains the natural cause of a decrease in biomass as succession peaks in a climax community?
once a climax community is reached, there are no nutrients left in the ecosystem to support the growth of plants.
the canopy of forests prevents sufficient light from reaching the forest floor, thereby limiting primary productivity.
humans usually cut down old growth forests.
the presence of large animals such as elk or wolves prevents the development of young animals.

answer: once a climax community is reached, there are no nutrients left in the ecosystem to support the growth of plants.

an ecological succession involves subsequent changes in the ecosystem because of change in biotic and abiotic factors. with each subsequent succession there is change in the ecosystem diversity. these changes continues until the ecosystem attains complete stability. the last stable level of succession includes the climax community. because of increase in diversity at each successional level the resources left till an ecosystem reaches the end climax community will not able to sustain the inhabiting species. once a climax community is reached, there are no nutrients left in the ecosystem to support the growth of plants as soil being the same abiotic factor in each successional level has lost it's fertility for growth of plants.

answer; i believe its echoic memory,it is believed to last three to four seconds; good luck