NUTRIENTS FROM Avicennia alba AND Rhizophora mucronata IN MANGROVE AND CRAB CONSERVATION AREA, TARAKAN CITY

Yulma Yulma — 2026-08-10

Mangrove ecosystems exhibit high productivity resulting from the decomposition of litter, which contains various nutrients such as carbon, nitrogen, and phosphorus that benefit both the mangrove plants themselves and the surrounding aquatic ecosystems. This study aims to determine the nutrient content (carbon, nitrogen, and phosphorus) of decomposed litter from Avicennia alba and Rhizophora mucronata. The study was conducted in the Tarakan City Mangrove and Crab Conservation Area, North Kalimantan, from April to June 2026, using a quantitative method with a descriptive-exploratory approach, taking into account the characteristics of the dominant mangroves at three study sites. The results showed that the decomposition rate of A. alba mangrove litter ranged from 0.22 to 0.64 grams/day and that of R. mucronata ranged from 0.25 to 0.67 grams/day; furthermore, no leaf litter from either A. alba or R. mucronata decomposed 100%. The carbon content of A. alba ranged from 9.45% to 13.45%, nitrogen from 0.64% to 0.72%, and phosphorus 0.25% to 0.29%, while the carbon content of R. mucronata ranged from 21.50% to 22.45%, nitrogen from 0.58% to 0.83%, and phosphorus from 0.06% to 0.009%. The values of the physical and chemical parameters of the water still support the decomposition process of litter.

THE ROLE AND IMPACT OF THE DWI TIRTO MULYO COOPERATIVE ON EMPOWERING PARTICIPATION AND THE SOCIO-ECONOMIC CONDITIONS OF MEMBERS OF KALIGRENJENG VILLAGE, BLITAR

Nazuwa Ayuni — 2026-08-10

This study aims to analyze the role and impact of the Dwi Tirto Mulyo Cooperative on empowering participation and the socio-economic conditions of members in Kaligrenjeng Village, Blitar Regency. This research uses a qualitative descriptive method with data collection techniques including observation, interviews, questionnaires, and documentation. The results show that the cooperative has a significant positive impact on members’ socio-economic conditions, indicated by improvements in employment (89%), income (98%), and access to capital (86%), all categorized as agree. Member participation is categorized as high in decision-making (94.74%), implementation (93.66%), benefit utilization (96.36%), and supervision (83.64%). Furthermore, the cooperative’s role in member empowerment is categorized as very high with an average of 94.13%. Overall, the cooperative has effectively improved members’ welfare, although improvements are still needed in supervision and financial service development.

THE EFFECT OF DIFFERENT TYPES OF BAIT ON THE CATCHES OF MANGROVE CRABS (Scylla serrata) USING FOLDING TRAP FISHING GEAR IN THE WATERS OF TANJUNG PECINAN MANGARAN DISTRICT SITUBONDO REGENCY

Diana Kamila Putri — 2026-08-10

This study was conducted to assess the effect of different bait types on the catch of mangrove crab (Scylla serrata) using a collapsible trap in the waters of Tanjung Pecinan, Mangaran District, Situbondo Regency. The purpose of this study was to determine the effect of bait type on mangrove crab catches. This study used a Randomized Block Design (RBD) method which included 3 treatments and 9 fishing trips. The bait types used were trash fish, field snails, and shrimp. Ten collapsible traps were used for each treatment, randomly spaced 5 meters apart. Additionally, supporting parameters included water quality, waves, current speed, temperature, and tides. Data were analyzed using SPSS with normality tests, homogeneity tests, ANOVA tests, and LSD tests. The data analysis concluded that trash fish and shrimp baits yielded better catches than golden apple snails.

ANTIBACTERIAL ACTIVITY OF Sargassum sp. IN INHIBITING Vibrio sp. ISOLATED FROM CANTANG GROUPER (Epinephelus fuscoguttatus x Epinephelus lanceolatus)

Shavika Miranti — 2026-08-10

Treatment of vibriosis using natural ingredients such as Sargassum sp. extract in cantang grouper cultivation activities needs to be studied. Testing the effectiveness of solvents in producing phytochemical compounds as antibacterials and modifying the extraction process to make it simpler aims to be replicated by farmers in the field. The tested bacterial isolates were isolated directly from cantang grouper fish showing symptoms of vibriosis from fish farmers in Senggarang Besar, Tanjungpinang City. Testing the antibacterial activity of Sargassum sp. extract in inhibiting the growth of Vibrio sp. was carried out through an inhibition zone test using the paper disc diffusion method (Kirby-Bauer method). The results showed that the use of 70% alcohol solvent in the extraction process resulted in a clearer and better inhibition zone diameter of 13 mm at the highest treatment concentration (10%) compared to the extract using 96% alcohol solvent at the same concentration of 11.67 mm. It should be noted that the inhibition zone formed is classified as partial because it is not clear or completely clear due to the presence of thin bacterial growth in the zone even though the circle shape of the inhibition zone is quite clear. The use of 70% alcohol solvent can be used for the extraction process of Sargassum sp. considering that it is cheaper and the results are better than 96% alcohol based on the results shown through this study.