Land use by the community for living and economy in the upstream region at the coastal Bay of Banten and the surrounding areas has started since the Kingdom of Banten Lama, whose central government was at Banten Girang. Conversion of mangrove forests into ponds in 1942 caused erosion in the uplands.
According to Drs. I Nyoman Sukmantalya, M. Sc, besides human error in using the land that produces large sediment, the erosion in the uplands is caused by rainfalls which are more than 3000 mm a year. Meanwhile, erosion in coastal areas is estimated to be caused by the onslaught of waves and currents that made tens of hectares of ponds disappear.
"Silting up the port is found around Karangantu port. In addition, the formation of Tombolo which is the connection between Dua Island and the island of Java can be found in this area," said Chief of Parangtritis Geospatial LAB, Saturday (6/ 11), in his open examination of UGM Geography Sciences Doctoral Program.
Defending his dissertation entitled Coastal Morphodynamics of Banten Bay Using Multi-temporal Remote Sensing Image, the man born in Denpasar, October 24, 1954, described the process of erosion in the old Ciujung delta, precisely in Tanjung Pontang, which is still taking place. That the formation of the Ciujung Delta that began in the Tengkurak village, Tirtayasa District became evident of accretion process is also active in that area. Therefore, with survey and mapping technology in the form of utilization of multi-temporal remote sensing image, he believes he can provide good coastal information.
The study, which he did in coastal areas of Banten Bay, Serang regency of Banten province, showed theoretical finding that showed morphodynamics in a bay with coastal areas that are different in the genetic land form, in the origin of volcanic land form the dynamics tend to be slower than those at the origin of fluvial landforms and marine landform origin. Meanwhile, the bay tends to narrow toward volcanic landform origin.
Meanwhile, practical finding indicates the coastal region of Banten Bay includes a very active hydrodynamics. This is indicated by the rapid erosion and accretion that requires conservation efforts inside it. One form of these conservation efforts is based on morphologic characteristics of the morpho-conservation. "Morpho-conservation Map of Banten Bay can be used as a basic consideration in protecting the Banten Bay coastal area against further damage," he said.
Nyoman added that coastal morpho-dynamics in Banten Bay and the surrounding area is the coastal region dynamics which have developed from time to time with varied intensity. Based on the results of the calculation, the rate of erosion of existing remote sensing image in the year 1994-2000 reached 72, 561 ha and the total accretion reached up to 188,866 ha. "This shows that between process of erosion and accretion, the accretion process has a tendency to dominate the development of coastal area in Banten Bay and its surroundings," said Nyoman who passed with "satisfying" distinction and became the 1302nd doctor from UGM.