Fixing nitrogen is an energy intensive process and it wasn't entirely clear exactly how the bacterium produces the energy it needs in order to perform.

固氮是一个加强能源的过程，而细菌为了完成任务而获取能量的过程目前尚不清楚。

youdao

One crucial part of this cycle-the fixing of pure nitrogen from the atmosphere into useful nitrogen-containing chemicals-depends more or less entirely on living things (lightning helps a bit).

氮循环的一个关键组成部分就是——在大气中，将纯净的氮固定为成含氮化合物的形式——这或多或少要完全依赖于生物(闪电仅起一点儿作用)。

youdao

Nitrogen for plant nutrition is mainly obtained from three sources: nitrogen-fixing plant, rain water and manure.

氮素是植物必要的营养元素之一，其主要来源有：生物固氮作用、降雨和灌溉水以及人工施肥。

youdao

He acknowledged that any soil used to grow nitrogen-fixing plants or were fertilised for agricultural reasons would result in an increase in gases involved in the formation of ozone.

BBC: Invasive plant 'increases ozone pollution'

Fossil fuel burning and fertiliser manufacture now take more nitrogen from the atmosphere than all of the planet's nitrogen-fixing microbes - and there are a lot of those bugs out there.

BBC: Leaving our mark: Fossils of the future