Comparison of Vegetation Structure and Community in Landslide Area and Non-landslide Area at Ir. H. djuanda Forest Park, Bandung

• Main Author: RAIHANDHANY (NIM : 11512047), REZA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30372
• Institution: Institut Teknologi Bandung

<p align="justify"> Ir. H. Djuanda Forest Park is a designated conservation area in Bandung, West Java. Inside this area there are extreme slopes, particularly along the access path from Gua Belanda to Maribaya. Landslides are a problem that frequently occur on these extreme slopes. These landslides are caused by various factors such as steep slopes, rainfall, soil and ground water conditions, and vegetation composition. Vegetation can act as a protective barrier to minimize the impact of landslides, since vegetation can reinforce land stability through interception, soil-binding, and evapotranspiration. Vegetation analysis was conducted on steep slopes at Ir. H. Djuanda Forest Park to describe the vegetation community structure and also to determine adaptive plant species. Vegetation analysis was conducted using nested plot method with sample plots measuring 20x20 meters for trees, 10x10 meters for poles and shrubs, 5x5 meters for saplings, and 2x2 meters for seedlings and herbaceous plants. Adaptive plant species was determined based on its presence in both landslide and non-landslide areas, and also its morphological characteristics. Adaptive plant species will be recommended for the rehabilitation of extreme slopes. Results showed that Pinus merkusii and Ficus variegata had the highest importance value index (IVI) (185.50 % and 27.40%) for trees, in both landslide and non-landslide areas. For poles, highest IVI in landslide area was recorded for Homalanthus populneus and Maesopsis eminii (112.70% and 45.60%), and Cinnamomum burmanni and Macaranga tanarius (85.3% and 45.2%) in non-landslide area. For saplings, highest IVI in landslide area was composed by Toona sureni and Mangifera foetida (35.20% and 19.90%), while non-landslide area was dominated by Calophyllum soulattri and Pterygota horsfieldii (66.10% and 45.20%). For seedlings, the highest IVI was recorded for Toona sureni and Ficus variegata (60% and 40%) in landslide area while non-landslide area was composed by Calophyllum soulattri and Pterygota horsfieldii (66.10% and 45.20%). Shrub species in both area types was dominated by Calliandra calothyrsus and Zapoteca tetragona (INP 64.9% and 43.7%). For herbaceous plants, Elatostema sp. had the highest IVI in both landslide and non-landslide areas (IVI 80.40% and 99.50%). Diversity index (H’) suggested that species composition in landslide areas was more diverse than non-landslide areas. In landslide areas, H’ ranged between 1.60–2.30, compared to non-landslide area 1.02–1.80. Similarity Index (IS’) between landslide and non-landslide area for trees, shrubs, and herbs ranged between 31.50% – 54.50%. Evenness Index (e’) in landslide area and non-landslide areas showed community stability at the tree and shrub levels, but not for herbs. Adaptive plants species for tree level were Pinus merkusii, Ficus variegata, Toona sureni, Cinnamomum burmanni, Pterospermum celebicum, Pterygota horsfieldii, Calophyllum soulattri, and Pouteria sp.; Laportea stimulans, Montanoa hibiscifolia, Zapoteca tetragona, Piper aduncum, Brugmansia suaveolens Trevesia sundaica, and Harmpsiopanax sp. for shrubs; whilst for herbs were Elatostema sp., Etlingera coccinea, Arenga pinnata, Syngonium sp., and Pteris sp. <p align="justify">