Keanekaragaman Jenis Tumbuhan Bawah di Kawasan Suaka Margasatwa Siranggas Kabupaten Pakpak Bharat Sumatera Utara

Abstract

Siranggas Wildlife Sanctuary is a natural reserve forest that has various species of understories in terms of the structure of the forest constituents, but the diversity of understory in the region has never been known. The purpose of the study was to determine the diversity of understory at the Siranggas Wildlife Sanctuary Area, Pakpak Bharat Regency, North Sumatra. The research was conducted from March to April 2022. The study location was determined by purposive sampling method at five different elevation sites; 800-900 masl, 900-1.000 masl, 1.000-1.100 masl, 1.100-1.200 masl and 1.200-1.300 masl with a plot size of 2m x 2m. Vegetation data were analyzed by using the Importance Value Index (IVI), Diversity Index (H'), the Uniformity Index (E), the Similarity Index (SI) and the Pearson Correlation Analysis. From the 1st location, it found 13 species of understories from 6 families with the highest INP value of 54,20% was Selaginella intermedia. The 2nd location had 14 species of understories from 8 families with the highest IVI value of 27,93% was also Selaginella intermedia. The 3th location had 14 species of understories and 9 families with the highest IVI value of 55,71% was from Phyllagathis rotundifolia. At the location 4, it obtained 19 species of understories and 9 families with the highest INP value of 26,56% was from Selaginella intermedia. The 5th location had 13 species of understories and 8 families with the highest INP value of 42,48% was from Begonia rostrata. All study sites obtained total 41 species of understories and 15 families with the highest IVI value of 28,6% was from Selaginella intermedia. The diversity index in all understory was classified as moderate, which has value 2,880. The understory plants uniformity index was relatively high at 0,775. The similarity index was highest at location 1 and location 4 with the value 47%. The correlation value between the understory diversity index and abiotic factors was unidirectional and opposite.