[填空题]
A student wants to set up an aquatic mes-tyqdc4i027x io zb r3ocosm (;-nktda: (o 61v nemc6gy:rcx *y 3aqwl p1rsusing seawater to simulate conditions in the food web (shown in the image below) and test its stability. He used seawater and sand from the area to set up the system and added some small organisms to the m66;ma-a yyclq g :rr:tn1vnx k( s*w1c3p(o edesocosm.
1.In the food web shown, identify an autotroph ,which is .
2.State a reason why phytoplankton shown in the food web would be a good addition to the mesocosm.
3.Discuss how saprotrophs perform a necessary function for the mesocosm.
4.Describe the disadvantages of using mesocosms in scientific investigations.
