生物地球化学循环代表什么? What do biogeochemical cycles represent?
A.
How certain nutrients move through the environment and are continually used and recycled 某些营养素如何通过环境并持续使用和循环利用
B.
How energy moves through trophic levels of an ecosystem 能量如何通过生态系统的营养水平移动
C.
How the adaptations of organisms change based on environmental pressures 基于环境压力的生物适应变化
D.
How biotic changes destroy unstable ecosystems 生物变化如何破坏不稳定生态系统