物质循环（Cycle of materials）： 生物所需要的元素多以无机形式存在于 空气、水、土壤与岩石中。
双语例句
1
The method reduces futile cycleofmaterials, and remarkably improves the production efficiency of equipment.
该方法减少了物料的无效循环，显著提高设备的生产效率。
2
Clearly, at the top of the economic cycle, consumers will be so desperate to get their hands on raw materials that they will pay well over the cost of production.
很清楚，在经济周期的顶部，消费者是如此难于得到原材料，以致他们宁愿支付高于生产成本的价格。
3
This means minimal energy consumption, good indoor climate and use ofmaterials with a low environmental impact in a life cycle perspective.