No abstract

Kasim F, Kadim MK, Nursinar S, Karim Z, Lamalango A. 2019. Comparison of true mangrove stands in Dudepo and Ponelo Islands, North Gorontalo District, Indonesia. Biodiversitas 20: 259-266. This study aimed to investigate and compare the current status of mangrove areas, as well as the composition and species diversity of mangrove stands in both regions of Dudepo and Ponelo Islands. The results showed that the mangrove areas calculated using the segmentation method in classifying image of Landsat-8 OLI (acquisition on September 2017) were 279.46 ha (Dudepo Island) and 113.35 ha (Ponelo Island) respectively. A total of 13 species of true mangrove were recorded from both islands, using survey method from 9 transect lines (TL), with a distance ranging from 40 to 210 meters (1-6 quadrats) per transect. The mean densities of trees were 2133 ± 329.78 ha-1 (Dudepo Island) and 2111 ± 234.28 ha-1 (Ponelo Island), while those of saplings and seedlings were 58 ± 13.48 ha-1 and 1425 ± 113.96 ha-1 (Dudepo Island), and 79 ± 14.51 ha-1 and 2963 ± 443.22 ha-1 (Ponelo Island). The mean diameter and basal area were 19.73 ± 10.65 cm and 84.22 ± 67.67 m2ha-1 (Dudepo Island), 17.04 ± 1.46 cm and 60.07 ± 15.12 m2ha-1 (Ponelo Island), respectively. The Importance Value Index (IVI) ranged between 3.97-114.87 (Dudepo Island) and 6.04-82.18 (Ponelo Island). The dominant and codominant species based on IVI in both islands were Rhizophora apiculata Blume and R. stylosa Griff. The indexes of diversity, richness, and evenness of mangrove species in both islands were 0.34-1.70, 0.48-1.18, 0.47-0.94 (trees), 0.00-1.10, 0.00-1.82, 0.00-1.00 (saplings), and 0.00.-1.48, 0.00-1.44, 0.72-1.00 (seedlings), respectively. The Bray-Curtis similarity index between Dudepo and Ponelo Islands, based on the overall values of community attributes, was 0.75.

The increasing of sea level due to climate change has been focused many research activities in order to know the coastal response to the change, and determine the important variables which have contribution to the coastal change. This paper presents a method for integrating Coastal Vulnerability Index (CVI), Multi Criteria Analysis (MCA) method and Geographic Information-System (GIS) technology to map the coastal vulnerability. The index is calculated based-on six variables: coastal erosion, geomorphology, slope, significant wave height, sea level change and tidal range. Emphasize has been made to the methodological aspect, essentially which is linked to: (i) the use of GIS technique for constructing, interpolation, filtering and resampling the data for shoreline grid, (ii) the standardization each rank of variables (0-1) and the use of several percentile (20%, 40%, 60%, and 80%) for each rank score, and (iii) the use of variable’s rank to map the relative (local) and standard (global) vulnerability of the coastline. The result show that for local, the index consist of four categories: very high (19.61%), high (68.63%), moderate (1,96%), and low (9.80%). Meanwhile, for global level, the index is constantly in low category.

This study aimed to investigate the community structure and distribution pattern of Gastropods in the mangrove ecosystem Bolihutuo village. The study was conducted in February and July 2021 in two different stations. Community structure analysis carried out includes species composition, density, diversity, evenness, dominance, and distribution patterns by Morisita dispersion index. The results showed that 13 species of gastropods were found from 8 families, namely Cassidula nucleus, Littoraria palescens, Chicoreus capucinus, Nasarius distortus and Phrontis polygonata, Nerita planospira, Faunus ater, Pirenella alata, Cerithidea obtuse, Telescopium Telescopium, Terebralia palustris, Terebralia sulcata and Monodonta labio. Gastropod diversity of each station in June was relatively higher than observations in February. The distribution of Gastropods has a clustered, random, and uniform pattern.Keywords: Bolihutuo, Community structure, distribution pattern, Gastropods, Mangrove

Memanfaatkan lahan dan sumber daya alam untuk tujuan ekowisata membutuhkan desain yang terkait dengan kesesuaian atraksi dan daya dukung wilayahnya. Penelitian ini bertujuan untuk menilai kesesuaian alokasi lahan kawasan dan daya dukungnya untuk kegiatan pariwisata di wilayah Pantai Tilalohe. Metode penelitian terdiri dari metode survei untuk kondisi bio-fisik dan penelitian literatur untuk karakteristik area pantai Tilalohe, serta kesesuaian dan daya dukung wilayah sebagai tujuan wisata. Hasilnya menunjukkan bahwa pantai Tilalohe secara geomorfologis memiliki karakteristik pantai saku. Jenis atraksi yang paling cocok adalah duduk dengan santai di semua stasiun pada lahan utama dengan luas 1315,45 m2 dengan garis pantai di sepanjang 114,84 m. Perairan di depan tanah utama, dengan luas 5965,20 m2 dan garis pantai 182,79 m, sangat mendukung pengunjung untuk kegiatan mandi dan berenang di wilayah timur. Studi ini menunjukkan peran penting analisis kesesuaian dan daya dukung untuk arahan peruntukan lahan untuk kegiatan ekowisata berdasarkan prinsip-prinsip perlindungan lingkungan dan keberlanjutan manfaat. Utilizing land and natural resources for ecotourism purposes requires a design related to the suitability of the attractions and its region's carrying capacity. This study aims to assess the suitability of the region's land allocation and its carrying capacity for tourism activities in the Tilalohe Beach area. The research method consists of survey methods for bio-physical conditions and literature research for the characteristics of the Tilalohe Beach area, as well as the suitability and carrying capacity of the region as a tourist destination. The results show that geomorphologically Tilalohe beach has characteristics of a pocket beach. The most suitable attraction is sitting casually at all stations on the main land with an area of 1315.45 m2 with coastlines along 114.84 m. This study shows an essential role of analysis of the suitability and carrying capacity of the area in the direction of land allotment for ecotourism activities based on the principles of environmental protection and the sustainability of benefits.