Structure and composition of riverine and fringe mangrove at Muara Kubu protected areas, West Kalima

AACL Bioflux. Vol. 12 No. 1 Page 378-393.

This paper describes the characteristics of riverine and fringe mangrove types at Muara Kubu Protected Areas, West Kalimantan, Indonesia. The characteristics of mangrove structure and composition were investigated to be used as a baseline for mangrove conservation management. Mangrove assessment through standard vegetation analysis includes area mangrove cover, species composition, distribution of diameter at breast height (dbh), density, basal area, frequency, significance value index (IVI), Shannon-Wiener diversity index (H’) and dominance index (D).

The significance of the difference between fringe and riverine mangrove were conducted using a t-test, and significantly different was defined at p-value < 0.05. Mangrove cover area in the study area has been measured at 3695.85 ha. We found 22 species and 11 families of true mangroves in the study area. Mangrove species which can generally be found in both riverine and fringe zone mostly come from the Rhizophoraceae family, including Rhizophora apiculata, R. mucronata, and Bruguiera gymnorrhiza. Specific species in the riverine zone were found include Excoecaria agallocha, Xylocarpus granatum, and X. moluccensis, while in fringe zones include Avicennia alba, Sonneratia alba, and S. caseolaris. Species with the respiratory root system are the main characteristic of the fringe type, this is due to the fringe zone facing the open sea.

The number of seedling and sapling mangroves which important for regeneration is significantly more in the riverine (20,600 trees ha-1 for seedling and 3,152 trees ha-1 for sapling) than in fringe type (13,875 trees ha-1 for seedling and 1,980 trees ha-1 for sapling). Mangrove tree density in riverine type (740±28 trees ha-1) is also significantly denser than fringe type (623±27 trees ha-1). Rhizophora apiculata is the most important mangrove species in both riverine (IVI = 235±7%) and fringe (IVI = 186±19%). Diversity index (H ') of mangrove trees in the fringe type (0.87±0.14) is significantly greater than in the riverine type (0.48±0.07). Dominance index (D) of mangrove tree in fringe type (0.56±0.07) is significantly lower than riverine type (0.77±0.04).

Resource Person: Achmad Fahrudin

Link: http://www.bioflux.com.ro/docs/2019.378-393.pdf