This ecosystem is one of the fascinating paradoxes of the biosphere: how do clear, and thus nutrient-poor, waters support such prolific and productive communities?
这个生态系统是生物圈中令人着迷的悖论之一：清澈而又缺乏营养的水域是如何支撑如此多产的群落的？
2
Recently planetary scientists have suggested that the external preconditions for the development of Earth's biosphere probably included four paramount contingencies.
最近，行星科学家提出，地球生物圈发展的外部先决条件可能包括四个最重要的偶发事件。
3
Biocycle is the cycling of chemicals through the biosphere.