植食性动物和肉食性动物在生态系统里扮演着哪些不可或缺的作用？

What are the indispensable roles of herbivorous and carnivorous animals in the ecosystem?

youdao

植食性动物和肉食性动物在生态系统里扮演着哪些不可或缺的作用？

What are the indispensable roles of herbivorous and carnivorous animals in the ecosystem?

youdao