translation.en: So if you know this leaf area index, you essentially have a measure of how much photosynthesis is possible in every plant, which again tells you how healthy each plant is.
translation.zh: 那么如果我们知道一棵树的 树叶面积指数， 就能大概测算出这株果树 在进行多少光合作用， 就能知道这株果树的健康状况。