[问答题]
1.Draw and label a trophic p;/ gnxo1fg/ox 5l 2yczyramid of energy showing four levels.
xo50 bq8sa+4ozfhgx wafb (c3-n3( us 2.Explain how the presence of a food web in an ecosystem makes it more stable than the presence of a single food chain.
3.The production and transfer efficiency of energy varies between ecosystems.
Describe how energy flows in and out of terrestrial ecosystems.
