大批量测定植物(互花米草)叶面积的一种新方法

叶面积的准确测定是评价生态系统能流、碳流和水分利用的重要基础.目前常用的叶面积测定方法都有其局限性,有些方法快捷、准确,但仅适用于小批量测定;大多数方法很难在较短时间内准确进行大批量测定.本文以互花米草叶面积测定为例,探讨了以扫描仪和叶片干重为基础,结合PHOTOSHOP图像处理技术,大批量、快捷、准确测定植物叶面积的方法--扫描-干重法.结果表明:虚拟正方形叶片边长与叶子像素成幂函数曲线关系,公式为419.85x^1.9693,R≈1.00;用此公式验证扫描-干重法,相对误差仅为3.651%.用扫描-干重法测得的结果与方格法相比无显著差异(P=0.473),表明该方法是可行的.

A new method of instantly measuring leaf area in large batches: a case study of Spartina alterniflora

Accurate measurement of leaf area is a foundation for evaluating energy flux, carbon flux, and water using of ecosystem. Current methods for measuring leaf area have various limitations and scope of use. Some of them are easy-to-use and accurate, but can only be used for small batches. It is very difficult for most methods to measure leaf areas in large batches in a relatively short period of time. In this study, we took Spartina alterniflora as an example to discuss a method based on scanner and dry-leaves weight, combined with Photoshop image processing technology, which can measure leaf areas instantly in large batches. Tested by a known power function relation between leaf length (y) and leaf pixel (x), ie. y=419.85x^1.9693 (R≈1.00), our new method only yielded 3.651% (n=30) relative error. There were no significant difference between this method and a classic square method (P=0.473). It is concluded that this method can be used to measure leaf area in large batches in a relatively short period of time, and to measure various shapes of leaves with little change in the vein.