DIVERSITY AND ECOLOGY OF UNDERSTORY PLANT IN SEMPU ISLAND, EAST JAVA, INDONESIA
Keywords:coastal vegetation, disturbance indicator, invasive alien species, lowland forest, Sempu Island, understorey plant
AbstractAs indicator for environmental disturbances, the understory is an important structural and functional component of forests ecosystems. Hence, this study was conducted to investigate the diversity and composition of understory plants in the lowland forests adjacent to the trekking paths along Semut Bay (dock entrance) to Segara Anakan Lagoon and some coastal areas in Sempu Island, and to detemine their association with the underlying environmental factors as disturbance indicators by the presence of understory invasive alien species (IAS). Sixty six plots of 2 x 2 m2 were established to analyze the understory vegetation, the site profiles and the environmental variables. A total of 135 understory plant species belonging to 108 genera and 60 families were recorded within the 66 plots of the study areas. Poaceae was the dominant family, followed by Compositae, Phyllanthaceae, Sterculiaceae, Rubiaceae, Putranjivaceae and Cyperaceae. The understory communities in the lowland forest adjacent to Semut Path were dominated by tree seedlings and had a relatively fewer composition of shrubs. Coastal areas, which have more open canopies, were dominated by grasses and shrubs. Some dominant native understory species include Ckistanthus ohlongifolius, Pterocymbium javanicum, lschaemum muticum, Guettarda spedosa, etc. Indicating disturbance, 12 understory IAS were found in the study areas. Four of these are among the worldâ€™s worst invaders (Chromolaena odorata, Imperata tylindrica, Lantana camara and Spathodea campanulata), and three are noxious weeds (Cyperus rotundus, Eleusine indica and Imperata cylindricd). The light intensity and air temperature were strongly positively associated with disturbed sites, while relative humidty, soil pH, and elevation were associated with less disturbed sites. These study results provide the scientific basis for management and recommendations on the current diversity status of the understory plant species at Sempu Island, hoping that these would justify further conservation of indigenous species and their protection from these disturbances.
LicenseAuthors who publish with this journal agree with the following terms:
- Authors retain copyright and grant the journal right of first publication, with the work 1 year after publication simultaneously licensed under a Creative Commons attribution-noncommerical-noderivatesÂ 4.0 InternationalÂ License that allows others to share, copy and redistribute the work in any medium or format,Â but only where the use is for non-commercial purposesÂ and an acknowledgement of the work's authorship and initial publication in this journal is mentioned.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).