Analysis of riparian vegetation in the Siwaluh River, Karanganyar District, Central Java, Indonesia

Abstract

Abstract. Pramadaningtyas PS, Chandrasari N, Izdihar RS, Iqbal WM, Cahyaningsih AP, Setyawan AD. 2023. Analysis of riparian vegetation in the Siwaluh River, Karanganyar District, Central Java, Indonesia. Intl J Bonorowo Wetlands 13: 45-56. This research was conducted in the Siwaluh River Basin region, Karanganyar District, Central Java, Indonesia. Land conversion into residential areas has lowered infiltration capacity, particularly in the Siwaluh River riparian vegetation, in the form of reduced or even lost vegetation that should serve as a water catchment area and habitat for riparian plants. The research was done to analyze riparian vegetation in the Siwaluh River to collect data for the conservation of the riparian zone, which plays a vital role in ecology and the ecosystem. Calculating the maximum IVI value and the existence of plant species from the diversity of riparian vegetation could determine the dominant vegetation type in a given area. The quadratic plot method employed was used; square plots of 20mx20m for trees, 10mx10m for poles, 5mx5m for saplings, and 2mx2m for seedlings were established at each sampling location. After that, the vegetation investigation comprised density, dominance, frequency, Shannon-Wiener diversity index, and IVI. The survey identified 209 plant species; Kigelia africana dominated the highest IVI value in tree habitus. Practically, in each upstream, middle, and downstream location, Bambusa sp. dominated the highest IVI in the pole habitus, Manihot esculenta controlled the highest IVI in the sapling habitus, and Ageratum conyzoides dominated the seedling habitus. Variations in the diversity index (H') of tree, pole, sapling, and seedling habitus result from reduced or even disappearing vegetation due to land changes. Therefore, it changes the distribution pattern of riparian vegetation.