Abstract
The authors propose a simple observation method of a micro climate in a suburban area based on the plant indicator. Yellow leaves of gingko as a plant indicator act as a measure of environmental conditions. The authors observed and analyzed the yellow leaves of gingko planted in the suburbs of Tokyo (Tama Newtown), in autumn. The processes of turn into yellow from green in ginkgo leaves are classified into simple patterns. From the results presented here, and we applied the logistic function as a mathematical model of the turn processes into yellow from green in ginkgo leaves. As a result, the expression was a well fit with the observed values.
