Article Per Year (5 Year)
p-Index From 2020 - 2025
0
P-Index
This Author published in this journals
All Journal Journal of Engineering and Technological Sciences LIMNOTEK - Perairan Darat Tropis di Indonesia
Luki Subehi
Research Centre for Limnology, Indonesian Institute of Sciences, LIPI Cibinong Science Centre (CSC) Cibinong 16911,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Engineering Environmental Science

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
Characteristics of Rainfall-Discharge and Water Quality at Limboto Lake, Gorontalo, Indonesia Subehi, Luki; Wibowo, Hendro; Jung, Kwansue
Journal of Engineering and Technological Sciences Vol 48, No 3 (2016)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (92.999 KB) | DOI: 10.5614/j.eng.technol.sci.2016.48.3.4

Abstract

Problems of high turbidity, sedimentation, water pollution and siltation occur at Limboto Lake, Gorontalo, Indonesia. The objective of this study was to analyze the rainfall-discharge relationship and its implications for water quality conditions. Secchi disk (water transparency), chlorophyll-a (chl-a), and total organic matter (TOM) were measured in May 2012, September 2012 and March 2013 at three sites of the lake (L-1, L-2 and L-3) to observe the impacts on the surrounding catchment. Based on representative stations for rainfall data from 2004 to 2013, monthly averages of rainfall in March-May (166.7 mm) and September (76.4 mm) were used to represent the wet and dry period, respectively. Moreover, sediment traps at these three sites were installed in September 2012. Based on the analysis it is suggested that rainfall magnitude and land use change at the Alopohu River catchment influenced the amount of materials flowing into the lake, degrading the water quality. Specifically, the higher average rainfall in May (184.5 mm) gave a higher average total sediment load (4.41 g/L/day). In addition, water transparency decreased with increasing chl-a. This indicates that the concentrations of sediment and nutrients, reflected by the high amount of chl-a, influenced the water quality conditions.
PENENTUAN BATAS TEPI DANAU PAPARAN BANJIR SECARA HITUNG PERATAAN KUADRAT TERKECIL DENGAN MULTIDATA PENGINDRAAN JAUH Julzarika, Atriyon; Dewi, Esthi Kurnia; Subehi, Luki
LIMNOTEK - Perairan Darat Tropis di Indonesia Vol 26, No 2 (2019)
Publisher : Research Center for Limnology

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Nowadays, technology and remote sensing data have developed significantly. These developments started with conventional data to become dynamic data. Technology and remote sensing data can be used for various applications such as mapping of inland water. Inland water resources that include lakes, rivers, and swamps are one of the national priorities, especially in lake mapping. One of the problems with floodplain lakes is that it is difficult to determine the fixed boundaries of the lake surface area. This study aims to obtain a forensic geological boundary mapping of a lake using the least-square adjustment approach in a floodplain lake with multi-data remote sensing. The floodplain lake in this study was Mahakam Cascade Lake in East Kalimantan Province. The fixed boundary of the surface area of the lake was determined using the least-square adjustment approach. One method in the adjustment was the harmonic modeling algorithm. This mapping used multi-data remote sensing in the form of Synthetic Aperture Radar (SAR) and optical imagery. The imagery used was Sentinel-1 which was acquired from 2014 to 2018 and Landsat from 2014 to 2018. This algorithm showed that the fixed boundaries of Mahakam Cascade Lake can be determined with certain tolerances. These fixed boundaries ignored lake tide parameters because the maximum tide value in the lake was only +5 cm. This value was ignored because the vertical accuracy of the topographic data in the big data engine was about 2 m. The fixed delineation of lake edges can be used to determine the lake volume and surface area. The surface area of the lake obtained from the Sentinel-1 imageries was ~ 399,017 km2. Based on Landsat imageries, the surface area of the lake was ~ 399,495 km2. The difference was due to the mixing of sediments and thin turbidity at the edge of the lake. This condition caused differences in reflectance values when acquisitioning the two types of imageries. Basically, this method could be applied for determining the edge of a lake.
Co-Authors Esthi Kurnia Dewi, Esthi Kurnia Hendro Wibowo Julzarika, Atriyon Kwansue Jung, Kwansue