Because of the geographical position, our natural rubber productivity is limited, and the increment of natural rubber demand in our country will be supplied by increasing import in future.
因为地理位置的原因，我国的天然橡胶产能受限，未来我国天然橡胶的需求增量要靠增加进口来补充。
2
Biomass increment, net primary production, and their allocation of the lower subtropical evergreen broad-leaved forest in Heishiding natural reserve were studied.
本文研究了黑石顶自然保护区南亚热带常绿阔叶林的生物量增量及其分配规律，净第一性生产量及其分配规律。
3
Both natural science and pure natural force are a pair of important categories in the process of value increment from the perspective of economic philosophy.