Statement I : Each trophic level has a certain mass of living material at a particular time called as the standing crop.

Statement II : The standing crop is measured as the mass of living organisms (biomass) or the number in a unit area.

Both statement I and statement II are correct .

The correct answer is Option (3) – Both statement I and statement II are correct.

Statement I: Each trophic level indeed has a certain mass of living material at a particular time, referred to as the standing crop. This term is used to describe the total biomass of living organisms present in a specific trophic level within an ecosystem at a given point in time.

Statement II: The standing crop is indeed measured as the mass of living organisms (biomass) or the number of organisms in a unit area. It provides valuable information about the productivity and structure of ecosystems, allowing ecologists to assess energy flow and nutrient cycling within ecosystems.The biomass of a species is expressed in terms of fresh or dry weight.