SPECIES RICHNESS AND RISK ANALYSIS OF WEEDS IN MONOCULTURE AND INTERCROPPING COFFEE PLANTATION, CISURUPAN, GARUT, WEST JAVA

• Main Author: Roihanul Hidayah, Syifa
• Format: Theses
• Language: Indonesia
• Subjects: Ilmu hayati ; Biologi
• Online Access: https://digilib.itb.ac.id/gdl/view/87668
• Institution: Institut Teknologi Bandung

The presence of weeds in coffee plantations can reduce the productivity of cultivated plants, some of them are invasive that negatively impact local biodiversity. Garut Regency, as one of the largest coffee producers in West Java, has various coffee plantation systems i.e. monoculture coffee plantations (CM), coffee plantations intercropped with chayote (CS), and coffee plantations intercropped with chili (CC). Weed management is often ineffective due to a lack of consideration for the invasive characteristics and management feasibility. This study aimed to identify the weed species richness in each coffee plantation system and analyze the risk of dominant species to determine effective management strategies. Plots 1x1 meter were placed using purposive random sampling. Importance Value Index (IVI) was calculated to identify dominant weed species, while Shannon-Wiener Diversity Index (H') was used to compare weed species diversity in each plantation systems. Principal Component Analysis (PCA) and clustering use to describe plantation characteristics based on species composition, while weed risk analysis was conducted using a scoring system. The results showed 59 weed species (19 native-invasive and 40 alien-invasive) across all plantations with Asteraceae group (17 species) dominating all location. Ageratum conyzoides, Alternanthera philoxeroides, Bidens pilosa, Commelina communis, Digitaria ciliaris, Eleusine indica, and Richardia brasiliensis identified as common species. The CC plantation had the lowest weed species number (25 species, H’=2.8), dominated by Galinsoga quadriradiata (IVI=27%) and Oxalis latifolia (IVI=23%); followed by CM plantation (27 species, H’=2.6), dominated by Drymaria cordata (IVI=33%) and Galinsoga parviflora (IVI=32%); the highest number of weed species found in CS plantation (40 species, H’=3.2), dominated by R. brasiliensis (IVI=24%) and B. pilosa (IVI=18%). PCA and clustering grouped the research sites into two clusters i.e. CM and CC-CS based on the simmilarity of weed species composition. Alternanthera philoxeroides, the species with the highest IVI (19%), has an invasiveness risk score of 268.8 which categorized as very high and a management feasibility score of 155.9 which categorized as negligible. Therefore, this species needs to be managed appropriately to mitigate its impact.