A study on Araceae species diversity and its distribution in Kelantan, Peninsular Malaysia

Araceae is one of the most diverse and abundant herbaceous plants in the tropical rainforest. This species favours moisture and shelter and is vulnerable to habitat disturbance. Drastic ecological changes will influence the distribution of Araceae in the forest. This study is designed to examine the influence of microhabitat, forest types, altitudes, and rock types on distribution of Araceae in the state of Kelantan, Peninsular Malaysia. The main objectives of this study are: (i) to identify the Araceae species through morphological characteristics, (ii) to determine the distribution of Araceae according to microhabitats, forest types, altitudes, and rock types, and (iii) to produce the Araceae conservation map for the state of Kelantan. Random sampling method was used in this survey. Correlation analysis using the Statistical Package for the Social Sciences (SPSS) was applied to examine factors influencing the distribution of Araceae. The Araceae conservation map was constructed using the ArcGIS version 10.5. The results show that a total of 57 species from 18 genera of Araceae were recorded in Kelantan, 14 species are rare and 43 are common. Three novel species are revealed, namely Alocasia farisii, Homalomena kualakohensis, and Homalomena stongensis. Three new records for Peninsular Malaysia are also discovered including Aglaonema cochinchinense, Aglaonema pumilum and Homalomena galbana. The microhabitat from the category of on-slope is the most significantly-preferred site for Araceae (x2 = 2177.280a and p-value = < 0.05) with 84.2 % species recorded. The lowland dipterocarp forest is the most significantly Araceae-rich habitat (x2 = 246.323a and p-value = < 0.05) with 96.5 % species recorded. The distribution of Araceae decreases gradually with the increasing altitudes, with a significant statistical analysis of x2 = 658.343a and p-value = < 0.05. In lower altitude, the altitudinal range of 100 – 199 meter a.s.l is the most preferable habitat for Araceae with 86.0% species. In higher altitude, the altitudinal range of 800 – 899 meter a.s.l. is the most significant range for Araceae due to rarity and endemism. The granitic area exhibits the most of Araceae diversity with a significant statistical analysis of x2 = 641.250a and p-value = < 0.05, with 82.5 % species recorded. However, the limestone area is the most significant area for conservation due to the higher level of rarity and endemism. This study also proposes an acreage of 247, 718 ha as in situ conservation for Araceae in Kelantan based upon the analysis on microhabitats, forest types, altitudes, and rock types. Meanwhile, the ex situ conservation for Araceae should integrate conservation with bio-economic potential for commercialisation in order to benefit the state government through development of biobusiness activities. Forty-one species of Araceae are identified through this study which have the economic potential as ornamental, medicinal, and edible produce. Exploiting the dicovered edible and medicinal species to produce natural extracts for food and cosmetic industries will capture the halal market potential enormously, thus generating new crop industries for state revenue earning.