Analisis Vegetasi Tumbuhan Invasif Tingkat Semak di Kebun Raya Sipirok Kabupaten Tapanuli Selatan Sumatera Utara

Abstract

The Sipirok Botanical Garden is a conservation area which has several forests that have been cleared as a result of remnants of coffee and rubber plantations owned by the community. Thus, it is easy for bush-level invasive plants to spread and invade on the forest ecosystem. The aims of the research are to analyze the invasive plant structure and thecomposition on the shrub level at the Sipirok Botanical Gardens, South Tapanuli Regency, North Sumatra. This research was conducted from January to August 2023. The method used was the Purposive Sampling method by using 5 research blocks. Each block used 2 routes with 1 transect consisting of 10 plots with a plot size of 5m x 5m on a zigzag manner. Vegetation data was analyzed using Importance Value Index (IVI) and Similarity Index (SI). The results of this study indicated that there were 58 species from 20 families of weeds on the shrub level.The most number of individuals, was Clidemia hirta, with 117 individuals from 2 families which were Fabaceae family with 15 species and Asteraceae family with 10 species. The importance value index of all species obtained was Clidemia hirta with the IV1 value was 2,07%. The highest important value index at each study block was different, block 1B was Clidemia hirta with value of 23,06%, block 5F was Austroeupatorium inulifolium with value of 14,49%, block 12B was Calliandra calothyrsus and Lantana camara with value of 9,93% block 7G was Clidemia hirta and Miconia oinochrophylla with value of 16,62%, and block 3A was Austroeupatorium inulifolium and Mimosa pudica with value of 9,88%. The Similarity Index of all blocks was obtained with the highest SI values at blocks 12B and 3A, which were 66,77%, were categorized as similar, while the lowest SI values was obtained at blocks 1B and 3A, with the value of 14,31%, and categorized as indistinguishable.