The other, nutrient depletion in the center of the rings from heightened competition with plants.

另一方面，由于与植物的竞争加剧，环中心的养分枯竭。

Given plants to draw their nutrients up from the soil, intense farming practices were thought to be the cause of nutrient depletion.

鉴于植物从土壤中吸取养分，密集的耕作方式被认为是养分枯竭的原因。