Roland Alexander Barkey, Roland Alexander
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MODEL OF CLIMATE AND LAND-USE CHANGES IMPACT ON WATER SECURITY IN AMBON CITY, INDONESIA Barkey, Roland Alexander; Mappiasse, Muh Faisal; Nursaputra, Munajat
Geoplanning: Journal of Geomatics and Planning Vol 4, No 1 (2017): (April 2017)
Publisher : Department of Urban and Regional Planning, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/geoplanning.4.1.97-108

Abstract

Ambon City is the center of national activities in Maluku province, established under Presidential Decree 77 issued in 2014 about spatial planning of Maluku Islands. Ambon is a strategic region in terms of development in agriculture and fisheries sectors. Development of the region caused this area to be extremely vulnerable to the issues on water security. Seven watersheds which are Air Manis, Hutumury, Passo, Tulehu, Wae Batu Merah, Wae Lela and Wae Sikula affect the water system in Ambon City. Therefore, this study was conducted to determine the impact of climate and land use change on water availability in seven watersheds in Ambon City. The analysis was performed using a Soil and Water Assessment Tool (SWAT) Model in order to analyze climate changes on the period of 1987-1996 (past), of 2004-2013 (present) and climate projection on the period 2035s (future) and equally to analyze land use data in 1996 and 2014. The results of the research indicated that land use in the study area has changed since 1996 to 2014. Forest area decreased around 32.45%, while residential areas and agriculture land increased 56.01% and 19.80%, respectively. The results of SWAT model presented the water availability amount to 1,127,011,350 m3/year on the period of 1987-1996. During the period of 2004-2013, it has been reduced to 1,076,548,720 m3/year (around 4.48% decrease). The results of the prediction of future water availability in the period of 2035s estimated a decrease of water availability around 4.69% (1,026,086,090 m3/year). Land use and climate change have greatly contributed to the water availability in seven watersheds of Ambon City. Ambon City is in need of land use planning especially the application of spatial plan. The maintenance of forest area is indispensable. In built-up areas, it is essential to implement green space and water harvesting in order to secure water availability in the future.
Karakteristik Tanah Longsor di Daerah Aliran Sungai Tangka Arsyad, Usman; Barkey, Roland Alexander; Wahyuni, Wahyuni; Matandung, Karla Kembongallo
Jurnal Hutan dan Masyarakat VOLUME 10 NOMOR 1, JULI 2018
Publisher : Fakultas Kehutanan, Universitas Hasanuddin

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24259/jhm.v0i0.3978

Abstract

Landslides occur as a result of ground movement on steep slopes, and the high humidity (moisture), and the sparse vegetation (open land). The Local conditions is an interrelated components. The process of landslides can be explained that the water soak into the soil will add weight to the ground. If the water penetrates the soil acts as a watertight sliding plane, the ground becomes slippery and soil weathering on it will move to follow the slope. This study aims to determine the type of landslide, landslide characteristics and landslides causing factors. This research was conducted in September 2015 in Watershed Tangka. The study consisted of three stages, namely the determination of the coordinates of the location of the landslide, landslide determining the location of the sample, the determination of the type of landslide, slope measurements, measurements of the dimensions of landslide and infiltration. Research results obtained are the coordinates of the location of as many as 17 points landslide, landslide types of translation and rotation, land cover and soil texture. There is no difference in the type of soil, infiltration rate, vegetation, geologi, slope and rainfall in both types of landslide are found. 
ANALISIS KOEFISIEN LIMPASAN PERMUKAAN KOTA MAKASSAR DENGAN METODE COOK Nganro, Sudirman; Trisutomo, Slamet; Barkey, Roland Alexander; Ali, Mukti
TATALOKA Vol 21, No 2 (2019): Volume 21 No. 2, May 2019 (in progress)
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/tataloka.21.2.%p

Abstract

Rain falling on the Watershed will turn into a stream in the river, this is because the rainwater is not entirely infiltrated into the soil, the unabsorbed water is called surface runoff. Factors affecting runoff are meteorological elements and drainage elements. This study aims to calculate the surface runoff coefficient using land cover maps 2017 and 2050, slope and soil type as parameters. Cook method divides the watershed characteristics into 4 sections as parameters to calculate the runoff coefficient of topography, soil type, vegetation cover and surface deposit. Each parameter is weighted based on its characteristics to calculate the coefficient of surface runoff symbolized by the letter C. The analysis results show that in the year 2017 obtained the value of C = 0.4734 and for the year 2050 C = 0.4785. There's a difference of 0.0051 coefficient of runoff value between land use map and land cover in 2017 and 2050. The results of this study will be used to calculate the flood discharge design in the object of research in Makassar City.