生态系统的营养结构是生态系统结构的重要级成部分,是生态系统能量流动和物质循环的渠道,这部分内容为学习生态系统的功能作辅垫,因而有必要 The nutritional structure of the ecosystem is an important part of the ecosystem structure, and it is a channel for the energy flow and material circulation of the ecosystem. This part of the study serves as a supplementary pad for learning the functions of the ecosystem and is therefore necessary.