ANALISIS SPASIAL FRAGMENTASI VEGETASI PADA HABITAT DAN KETERKAITANNYA DENGAN POPULASI OWA JAWA (HYLOBATES MOLOCH)

• Main Author: Hadi, Firman
• Format: Dissertations
• Language: Indonesia
• Subjects: Ekologi
• Online Access: https://digilib.itb.ac.id/gdl/view/86581
• Institution: Institut Teknologi Bandung

There are 14 species of gibbons in the world and all of them only live in Asia. From 6 species of gibbons found in Indonesia (Sumatera, Java and Kalimantan Islands) only Javan Gibbon (Hylobates moloch) is included in the IUCN Red List of Threatened Species. The identification of forests that have the potency to support viable Javan Gibbon population is an important process to support the conservation efforts. The most common technique applied to achieve this is to carry out the measurement in the field. This technique is not efficient if applied in a larger area. One of the solutions to eliminate the problem is using the remote sensing technology. Remote sensing data analyses can produce a quick and reliable information of large area. This technique can also be applied to know the level of habitat fragmentation. The aim of this research is to produce the algorithm of remote sensing data processing to identify the habitat of Javan Gibbon and to produce the map of Javan Gibbon habitat based on its level of fragmentation. This information will be useful in developing the strategic plan of Javan Gibbon conservation based on the Javan Gibbon density and the fragmentation level. The result of this research will also useful to define the appropriate site for Javan Gibbon reintroduction. From 93 points of Javan Gibbon groups collected, it is found that 72% of Javan Gibbons live in elevation between 1000 - 1500 m. above sea level (asl.). Predictive model of Javan Gibbon distribution using Maximum Entropy (Maxent) shows that Javan Gibbon distribution is affected by elevation and distance from the roads. The probability of Javan Gibbon to be found in one location is higher in areas located in 1000 - 1250 m. asl and 800 - 900 meters from roads. The result of this research shows the different characteristics of vegetation structure between areas with Javan Gibbon and areas without Javan Gibbon. The mean of tree height in areas with Javan Gibbon is 11,72 meters while for those without Javan Gibbon is 7,73 meters. The mean of canopy coverage in areas with Javan Gibbon is 75 % and for those without Javan Gibbon is 65%. There is no significant result to differentiate between the tree size diversity between the two areas. The results also show that the Javan Gibbon population inWest Java are facing extinction due to the forest lost, forest- and habitat fragmentation. Spatial analyses using the transformed Landsat MSS/TM/ETM+ from the year of 1976, 1989/1991 and 199/2001 show the decline of forest coverage. In the year of 1976 the forest cover is 325.930 hectares, while in 1991 it became 289.608 and in 2001 the forest cover left only 174.808 hectares. The decrease in the length of forest edge, the mean area of forest patches and the decrease in the degree of connectivity between forest patches indicate that the forest fragmentation occurred in West Java during the same period. The length of forest edge decreased from 10.620,1 kilometers in 1976 to 5.786,3 kilometers in 2001. The mean area of forest patches decrease from 760 m2 in 1976 to 418 m2 in 2001. Forest connectivity analyses using the Probability of Connectivity (PC) model explain the change of PC indices of forest patches. The PC index also reveals the importance of Gunung Simpang - Tilu Nature Reserve and its surroundings for the conservation of Javan Gibbon population in West Java. GLCM Entropy image texture of Band 3 SPOT 5 is proven can be used in modeling the canopy coverage and tree height. By applying the model, it is also verified that fragmentation occurs in Javan Gibbon habitat in Tangkuban Parahu Nature Reserve. Canopy cover variable which was derived by implementing FCD Model to Landsat ETM+ image, can be used to quantify the habitat shape metrics. SHAPE_AM variable correlates with the abundance of Javan Gibbon and can be applied to monitor the habitat quality of Javan Gibbon. The conclusion of this research is that Javan Gibbon populations in West Java are currently facing threat from the forest and habitat fragmentation simultaneously. Forest fragmentation causes the decrease of genetic variability within the Javan Gibbon population due to minimal probability of cross-breeding between populations. The low connectivity between forest patches will increase the chance of Javan Gibbon extinction in the long time. Habitat fragmentation will accelerate the rate of extinction due to its direct effect to Javan Gibbon populations in reducing their capability to utilize the resources within their habitat.