Pembangunan indek biokimia bagi spesies tumbuh-tumbuhan hutan hujan tropika menggunakan spektroradiometer lapangan

Abstract

Biochemical elements such plant pigment chlorophyll, carbon, nitrogen and water can affect the physiology and penology development of the plants. However, the traditional method of foliar analysis is no longer able to meet the growing need for biochemical element information. Consequently, this research aims to use vegetation index (VI) model as an alternative method for the production of biochemical element information. During this research, spectrum bands selected either using spectrum transformation divergence (TD) or genetic algorithms-spectrum angle mapper (GA-SAM) method were tested on the three main groups of VI involved of (i) simple ratio (ii) different ratio, and (iii) double ratio. Strong correlation at R value more than 0.8 (at p-value<0.001) between VI model and the field biochemical elements is proficient to estimate biochemical elements of plants. From this study, we can see that the strong correlation formed through the spectrum band selection method of GA-SAM applied in WIGA-SAM for six types of dipterocarp species namely neobalanocarpus heimii sp. (NEOBHE sp.), shorea acuminate sp. (SHORAC sp.), shorea leprosula sp. (SHORL1 sp.), shorea lepidota sp. (SHORL2 sp.), shorea pauciflora sp. (SHORP2 sp.) and shorea maxwelliana sp. (SHORM2 sp.). This findings show that WIGA-SAM capable to help us in determining water content in the leaf tissue. In future, this WIGA-SAM method is very useful in determining water content of the six similar types of dipterocarp species found in a tropical rainforest environment.