[问答题]
A student wanted to study how food chains in leaf litter can be
pxz 2mn)p5 -g7.eivla -t yyk-c96g wlaffected by the mass of initial leaf litter added. The student placed an increasing mass of leaf litter in three different tree holes and waited a few weeks. To collect data, the student collected all the leaf litter and placed it in an apparatus, as shown below. The heat from the light bulb dried out the litter from above and the heat and light drove the invertebrates through
9t6ky l -gcyw-the wire mesh to the beaker below. The invertebrates were collected, the number of species counted, the species were identified and then they were put into their respective trophic groups.
1.(1)State the independent variable in the experiment.
(2)State the dependent variable in the experiment.
2.Suggest how the dry biomass of the leaf litter can be obtained.
3.Explain why using the dry biomass of leaf litter is advantageous to using the fresh biomass.
4.From the two graphs provided, describe the results of the experiment.
