ANALYSIS OF PHOSPHATE SOLUBILIZING BACTERIA FROM MANGROVE SEDIMENTS AND THEIR RELATION TO BIRD PRESENCE IN PULAU RAMBUT WILDLIFE RESERVE, DKI JAKARTA

• Main Author: UTARI DEWINA (NIM : 10614021), RESTU
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30345
• Institution: Institut Teknologi Bandung

<p align="justify">Mangrove forests provide important ecosystem services. Microbes play a key role in the functioning of these ecosystems, i.e., in the decomposition of organic nutrients into inorganic form so that they can be used by plants. Inorganic phosphate is a limiting factor for mangrove growth, thus the presence of phosphate solubilizing bacteria (PSB) is important in mangrove forest ecosystems. Besides microbes, birds are organisms that act as sources of available phosphate. The island of Pulau Rambut in DKI Jakarta province is an avian wildlife sanctuary with an uneven distribution of birds in its mangrove forests. This variation in bird abundance is expected to have an impact on the mangrove ecosystem and its PSB community structure. The objective of this study was to determine the PSB community structure in sediments and relate them to the presence of birds as a source of available phosphate. PSB were isolated from mangrove sediments from the northern area of the island which has been observed as a bird nesting site, and from the western area which is not a bird nesting site. PSB were isolated using National Botanical Research Institute's Phosphate selective medium, then abundance, species richness, and Shannon-Wiener diversity index (H’) for both sites, as well as the Sorensen similarity index, were calculated. The PSB diversity index was then correlated with biotic and abiotic factors in each site by Pearson correlation. Five PSB species were found in both the nesting and non-nesting sites with a Sorensen similarity index of 71.42%. The PSB diversity index in the non-nesting site (1,23) was higher than in the nesting site (1,11), due to the higher abundance of PSB in the former site. Molecular analysis by 16s rRNA identified the predominant bacteria species as Salinicola tamaricis. PSB diversity was significantly correlated with several factors, i.e., positively correlated (r>0,900) with soil organic C, and negatively correlated (r< -0,900) with soil salinity, amount of available phosphate, and total soil phosphate.<p align="justify">