Claim Missing Document
Check
Articles

Found 28 Documents
Search

Pengaruh Kerapatan Vegetasi Penutup Lahan terhadap Karakteristik Resesi Hidrograf pada Beberapa Subdas di Propinsi Jawa Tengah Dan Propinsi DIY Bokiraiya Latuamury; Totok Gunawan; Slamet Suprayogi
Majalah Geografi Indonesia Vol 26, No 2 (2012): Majalah Geografi Indonesia
Publisher : Fakultas Geografi, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (735.591 KB) | DOI: 10.22146/mgi.13418

Abstract

ABSTRAK Penelitian ini dilakukan di Propinsi Jawa Tengah dan Propinsi DIY, dilatarbelakangi oleh penurunan daya dukung lingkungan seperti rusaknya kawasan hutan dan berkurangnya luas tutupan lahan hutan, yang dapat mempengaruhi perilaku aliran air. Dengan adanya perubahan tutupan lahan akan berdampak pada berubahnya sifat-sifat hidrologi seperti koefisien aliran, debit dan karakteristik hidrograf aliran. Indikator kerusakan hutan dapat dilihat dari karakteristik hidrograf. Evaluasi respon DAS berupa hidrograf aliran akibat adanya perubahan penutup lahan menjadi sangat penting untuk dianalisis karena merupakan tolok ukur dalam setiap penentuan kebijakan terkait dengan penanganan banjir dan tanah longsor. Oleh karena itu, penelitian ini bertujuan untuk (1). mengkaji karakteristik kerapatan vegetasi penutup lahan dan keterkaitannya dalam ekosistem DAS, (2). mengkaji karakteristik aliran dasar (koefisien resesi)  pada beberapa sub-DAS tersebut, dan (3). menganalisis pengaruh kerapatan vegetasi penutup lahan terhadap karakteristik hidrograf aliran khususnya aliran dasar pada sub DAS yang diteliti. Metode penelitian yang digunakan adalah metode survei data sekunder pada rekaman data AWLR/SPAS untuk analisis resesi hidrograf dan koefisien resesi (Krb), dan interpretasi citra Landsat ETM+ untuk transformasi indeks vegetasi NDVI dikorelasikasi dengan data kerapatan vegetasi untuk mempresentasikan karakteristik kerapatan vegetasi. Selanjutnya hasil transformasi indeks vegetasi NDVI kemudian diujikorelasikan dengan karakteristik resesi (koefisien resesi) untuk menganalisis pengaruh kerapatan vegetasi penutup lahan terhadap karakteristik resesi hidrograf. Hasil uji statistik NDVI dengan koefisien resesi menunjukkan terdapatnya korelasi antara nilai NDVI dan koefisien resesi pada R2 = 0,1427, F = 2.17 tidak berpengaruh nyata pada taraf signifikan 1% sebesar 0.1646 (lampiran 1.2b). Analisis korelasi antara variabel independen (NDVI penutup lahan) dengan variabel dependen (koefisien resesi) memiliki korelasi sangat lemah sebesar 0,077. Hasil ini menunjukkan bahwa parameter kerapatan vegetasi NDVI sangat lemah untuk mengontrol keberadaan aliran-aliran rendah. Karena besarnya simpanan (storage) airtanah tergantung pada besarnya air yang mencapai akuifer. Setelah sumbangan air pada akuifer terhenti, maka air yang tertampung di akuifer akan mengalami pengatusan yang besarnya tergantung kondisi akuifer tersebut. Gerakan air pada akuifer disebabkan oleh gaya gravitasi, kecepatan dan jumlahnya terutama dipengaruhi oleh karakteristik batuan. Karakteristik batuan mempengaruhi pergerakan airtanah, diketahui dari daya hantar hidrolik batuan tersebut.  ABSTRACT This research was conducted in Central Java and DIY province, as a respond to the decrease of environment capacity such as forest destruction and widespread loss of forest land cover which affect water flow behavior. Land cover change will affect the hydrological properties such as coefficient, rate, and hydrograph characteristics of flow. The indicators of forest destruction can be seen through hydrograph characteristics. Flow hydrographic as an evaluation of river catchment responses to land cover change becomes very important to analyze because it is a benchmark in determination any policy about flood and landslide handling. Therefore, the aims of this study are: (1) to examine the characteristic of land cover vegetation density and its association in river catchment ecosystem, (2) to examine base flow characteristics (coefficient of recession) at these river catchments, and (3) to analyze the influence of land cover vegetation density on flow’s hydrograph characteristic, especially base flow at river catchments. The method used in this research is secondary data survey on AWLR/SPAS data record in order to analyze hydrograph recession and coefficient of recession (Krb), and to interpret ETM Landsat image for NDVI vegetation index transformation for the characteristic of vegetation density. The results of NDVI vegetation index transformation then tested it’s correlated with recession characteristics (coefficient of recession) to analyze the influence of land cover vegetation density on hydrograph recession characteristic. The results showed there is an average value of vegetation density (NDVI) for the river catchments and most of it has mediocre vegetation density level with the percentage of land cover vegetation less more than 30%. Most of base flow recession characteristic (coefficient of recession) lay on relatively high range, i.e. 0.661 to 0.980. Correlation analysis between independent variable (land cover NDVI) with dependent variable (coefficient of recession) is very weak, only 0.077. This result shows that the parameter of NDVI vegetation density can be combined with aquifer formation to control the existence of lower flow. Because the magnitude of soil water storage is depend on water volume that reach the aquifer, the arrangement of optimal hydrogeology condition along dry season (no rain season) depend on geological aquifer condition. 
The spatial dynamics of land cover change along the Wallacea corridor in the key biodiversity area ‘Buano Island’, Maluku, Indonesia Bokiraiya Latuamury; Hendrik S E S Aponno; Husain Marasabessy; Miranda H Hadijah; Wilma N Imlabla
Journal of Degraded and Mining Lands Management Vol 7, No 4 (2020)
Publisher : Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15243/jdmlm.2020.074.2241

Abstract

Land cover change is an urgent global issue that needs to be addressed immediately. Its dynamics are of the greatest importance to Key Biodiversity Areas (KBAs) along the Wallacea Corridor, including Buano Island, whose land and sea are rich in biodiversity. KBA Buano Island is home to endemic and endangered birds, such as Moluccan scrubfowl (Eulipoa wallacei) and black-chinned monarch (Monarcha boanensis). Black-chinned monarch only lives on the island (single-site species). Buano waters have an interestingly diverse life, including dugong (Dugong dugon), hawksbill turtle (Eretmochelys imbricata), loggerhead turtle (Caretta caretta), and many species belonging to the dolphin family (Delphinidae) and beaked whale family (Ziphiidae). This study was designed to analyze and map the spatial-temporal patterns of land cover changes on Buano Island. It employed a multi-temporal analysis on Landsat images from 1970, 1980, 1990, 2000, 2010, until now, and a t-test to analyze the results further. The t-test analysis produced t-count ≥ t-table at confidence level (α) of 0.05, indicating significant changes in land cover from 1970, 1980, 1990, 2000, 2010, until 2016. These multitemporal-spatial dynamics were attributable to fluctuation in population growth and open and straightforward access between the island and the capital of the regency. Furthermore, from the aspect of fishery and maritime affairs, Buano Island already had synergistic land area development.
Characterizing River Baseflow Recession Using Linear Reservoir Model in Alang Watershed, Central Java, Indonesia Bokiraiya Okky Latuamury; Lydia Riekie Parera; Husein Marasabessy
Indonesian Journal of Geography Vol 52, No 1 (2020): Indonesian Journal of Geography
Publisher : Faculty of Geography, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (720.062 KB) | DOI: 10.22146/ijg.43565

Abstract

Alang is a sub-watershed emptying into the Gajah Mungkur Reservoir in Wonogiri, Central Java Indonesia, with an area of 51.01 km2 and lithology composed of Baturetno Formation and Wonosari Formation. Baseflow is a major component of river flow during the dry season. Hence, the characterization of its recession becomes necessary, and it can be performed with innovation in baseflow hydrological modeling, that is, the recession curve. This study was designed to describe the distinctive features of baseflow recession using a linear reservoir model, which is depicted in individual and master recession curves. The baseflow recession in AlangSubwatershed was represented by a combination of varying initial recession discharge (Q0), α, and recession constants (Krb). The individual recession curves were typified by Q0=0.19-9.11, α= 0.089-0.243, and Krb=0.7843-0.9148. As for the master recession curve, it had Q0=9.99, α=0.085, and Krb=0.928. These results signify a sloping recession curve, meaning that the water storage and aquifer characteristics that store and transmit water in Alang Subwatershed are in good condition.
HUBUNGAN ANTARA INDEKS VEGETASI NDVI (NORMALIZED DIFFERENCE VEGETATION INDEX) DAN KOEFISIEN RESESI BASEFLOW PADA BEBERAPA SUBDAS PROPINSI JAWA TENGAH DAN DAERAH ISTIMEWA YOGYAKARTA Bokiraiya Latuamury
Jurnal Teknosains Vol 2, No 2 (2013): June
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/teknosains.5998

Abstract

The background of this research is the decrease of environment capacity in cacthment ecosystem, especially impact of vegetation forest on behavior streamflow. The indicators of cacthment destruction can be seen through hydrograph characteristics. Evaluation of cactment respons of flow hydrographic as an evaluation tools of river catchment responses becomes very important to analyze because it is a benchmark in determination several policy about flood, drough, sedimentation and landslide handling. The research purpose is to analyze the relationship between vegetation index NDVI (Normalized Difference Vegetation Index) and the characteristic of baseflow recession coefficient at several subcatchment areas in province of Central Java and Specific District of Yogjakarta.The method of this research is surveillance on data recording of AWLR (Automatic Water Level Recorder) and data of River Flow Measuring Stations in order to separate the baseflow by calibration curve, and image interpretation of Landsat ETM+ for the transformation of vegetation index (NDVI-Normalized Difference Vegetation Index).The analysis on recession coefficient data (Krb) and NDVI were correlated to analyze the strength of relationship between these two parameters. The results of statistical analysis on index NDVI and recession coefficient showsthat NDVI and recession coefficient value at R2 is 0.1427, F = 2.17 which is not significant at 1% significance level of 0.1646. The result shows a very weak correlation of 0.077 which mean that vegetation density (NDVI index)has a very weak control on low flows. Basically, river baseflow is a genetic component of river flow which comes from aquifer storage and/or other low flow sources. Thus, geology and soil have a significant effect on baseflow.
KAJIAN KONSEPTUAL PEMODELAN PERUBAHAN PENGGUNAAN LAHAN UNTUK STUDI ILMU LINGKUNGAN Bokiraiya Latuamury
Jurnal Teknosains Vol 3, No 1 (2013): December
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/teknosains.6124

Abstract

Modeling is one of the methods in the portfolio of techniques and approaches available to unravel the dynamics of the land-use system. In this perspective, models are used as a learning and communication tool between researchers to formalize knowledge on the dynamics of land-use change. Land-use system is a very complex system, such that computer modeling is needed as a computational laboratory to estimate and test hypotheses about the process of land-use change. One of the major difficulties in multi-disciplinary research is to find ways to express oneself, which are acceptable to all the disciplines involved and free from the connotation of any or all of them. Land-use change models play an important role in exploring possible future developments in the land-use system. This paper attempts to show the methods and approaches to be used as a communication and learning environment for stakeholders involved in the decision making about land-use change systems in the field of environment
ANALISIS KURVA RESESI ALIRAN DASAR MENGGUNAKAN MODEL RESERVOIR LINIER RECESSION CURVE HYDROOFFICE PADA DAS WURYANTORO KABUPATEN WONOGIRI PROPINSI JAWA TENGAH Bokiraiya Okky Latuamury
Jurnal Teknosains Vol 7, No 1 (2017): December
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/teknosains.32395

Abstract

The hydrograph recession curve expresses the theoretical relationship between the aquifer structure and the flow of groundwater flowing into the river basin channel. These theoretical relationships are often empirically depicted using the base flow recession curve. The hydrograph recession curve is commonly used to estimate the recessionary parameters, aquifer properties and to evaluate alternative hydrological hypotheses. The river basin hydrograph recession curve records the behavior of the relationship between the aquifer structure and its association with groundwater outflow to the river channel. This research was conducted with the aim: to analyze the characteristics of the baseflow recession based on the parameters and coefficients of the recession, and the shape of the individual recession curve and the master recession curve. The characteristics of the baseflow recession to research sub-watershed have the recession curves tend to sloped, describing the water storage well enough. The parameter Q0 (recession early), α and the recession constant Krb ranging from 0,80 – 0,90 for the individual and master recession curve in all three research sub-watershed. This calculation result indicates that the recession characteristics in three research sub-watershed have the condition of water storage is excellent, because they are supported by the aquifer characteristics dominated by the geological structures are more permeable (porous).
KAJIAN KEBERLANJUTAN ALIRAN DASAR SUNGAI MELALUI ANALISIS KURVA RESESI HIDROGRAF PADA DAS KEDUANG KABUPATEN WONOGIRI PROVINSI JAWA TENGAH Bokiraiya Latuamury; Hendrik S.E. Aponno; Miranda H. Hadijah
JURNAL HUTAN PULAU-PULAU KECIL Vol 1 No 3 (2017): JHPPK
Publisher : Program Studi Manajemen Hutan, Pascasarjana Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1119.29 KB)

Abstract

The streamflow hydrograph recession curve notes that behavior of the relationship between the aquifer structure and dependencies with the groundwater outflow towards river basin channel. The recession behavior of river basin hydrographs will investigate to understand the hydrology processes of the river basin in the future. This research was conducted with the aim: to analyze the characteristics of the baseflow recession based on the parameters and coefficients of the recession, and the shape of the individual recession curve and the master recession curves both manually and through the processing of genetic algorithms using a linear reservoir model of hydrooffice software package recession curve (RC) 4.0. The results of the visualization of the recession curve shape of the watershed of the research shows there is a very interesting trend in the watershed storage process.The characteristics of the baseflow recession to research watershed with the recession curve slope describe the baseflow recession conditions, especially excellent water storage. The river basin of Keduang have the form of a relatively sloping recession curves, both individual and master recession curve with relatively high recession constant ranged between 0,80 – 0,90 have baseflow recession characteristic is excellent, i.e. the watershed water storage which is the higher volume of water storage.
ANALISIS KUALITAS KIMIA AIR SUNGAI RIUAPA DAN DAMPAKNYA TERHADAP LINGKUNGAN Elna Soukotta; Robert Ozsaer; Bokiraya Latuamury
JURNAL HUTAN PULAU-PULAU KECIL Vol 3 No 1 (2019): JHPPK
Publisher : Program Studi Manajemen Hutan, Pascasarjana Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (785.745 KB)

Abstract

Riuapa river is an integrated part of Waeriuapa Watershed that usefull for people around the area as agriculture irrigation, livestock, fresh water fish pond, and other domestic use for people activities. As an open watershed ecosystem, that flow into the sea, the river of Watershed was received various input from outside, either from upland to the estuary. Those input were domestic household waste, farming activities waste, and input from land erosion and land slide. The study was conducted to identify water quality through polutant level measurement, in the river and in the flood plain, especially for Chemical polutant element. Red waste, farming activities waste, and input from land erosion and land slide. The study was conducted to identify water quality through polutant level measurement, in the river and in the flood plain, especially for Chemical polutant element. Result of analisys using Statistical Analisys, namely, Factorial Design in Randomized Completly Design (3x2x3), as follows: Location of station in the river and Season factor was significant influence the chemical variable of BOD, COD, Nitrite, and Chlor in the river, and shallow well as well, at the level of beyond National Water Quality Standard, and affected environmental around the area. Changging of upper land cover of Waeriuapa Watershed was significant effected to water debit, fluctuation of rainfall and effected to liquidity process of water quality, that increase of BOD from 2.9 mg/l in dry season to 4.6 mg/l in rainy season; COD from 2.9 in dry season to 21.3 mg/l in rainy season; Nitrite content of 0.0001 mg/l in dry season to 0.0022 mg/l in rainy season.
PENGARUH VARIASI PENGGUNAAN LAHAN PADA BERBAGAI FORMASI GEOLOGI TERHADAP RESESI ALIRAN DASAR DI DAS WURYANTORO PROPINSI JAWA TENGAH Bokiraiya Latuamury; sudarmadji sudarmadji; slamet suprayogi
SPATIAL: Wahana Komunikasi dan Informasi Geografi Vol 17 No 1 (2017): Jurnal SPATIAL - Wahana Komunikasi dan Informasi Geografi, Volume 17 Nomor 1, Ma
Publisher : Department Geography Education Faculty of Social Science - Universitas Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (589.843 KB) | DOI: 10.21009/spatial.171.08

Abstract

In the environmental viewpoint, water and land characteristics are strongly influenced by some aspects such as layout, position, landscape development, natural factors and human activity impact.Spatial aspects of land and water resources are the asset of spatial-based national development. Land resources management need to consider the characteristic of both renewable and nonrenewable land resources.Hydrological characteristics is a result of interaction and interrelation of human socio-economic parameters with some watershed physical factors. Apart from that, besides land use as physical factors, there are some other factors such as morphometry, lithology, geomorphology and geology. They are all naturally come from a watershed that cannot be altered by a human (unmanageable). Some combination of watershed physical factors and the manageable factors such as land use plan, slope, and slope length will give a specific watershed response to the rainfall. Eventually, this affects the large-small of river flows behavior. Baseflow river is an essential substance for the development of water resource management strategies at watershed scale. Therefore, this study aimed to estimate baseflow river recession at various geological formation. It also influences characteristics of baseflow recession in Wuryantorosub-watershed at Wonogiri district. Simultaneous Statistical Analysis (ANOVA) and partial (t-test) analysis show that there is a significant influence on the variation of land use in diverse geological formations toward the baseflow recession, with a determination coefficient value - Adjusted R-square is 58.1%.The simultaneous analysis describes a simultaneously effect of recession baseflow coefficient with value test of the test F table > F count at a level of confidence by 5%, and a partial analysis shows that all land use variations in three geological formations significantly influence baseflow recession. Recession model of these two relations is Y = 1.426 + 0,583X1 + 0,384X2 + 0,269X3. This condition indicates that baseflow recession is influenced by some basic by a number of entire environmental attributes. Thus, there will be a sustainable synergy of baseflow recession management that maintain river pattern by the surrounding inhabitant as an alternative water supply for local communities. Keywords: Baseflow, perennial river, variations in land use, geological formations
Land use change and baseflow recession modelling in Wuryantoro Watershed, Wonogiri Regency, Central Java Province, Indonesia Bokiraiya Latuamury; Mersiana Sahureka; Wilma Nancy Imlabla; Miranda H Hadijah; John F Sahusilawane; Husain Marasabessy; Moda Talaohu
Journal of Degraded and Mining Lands Management Vol 10, No 1 (2022)
Publisher : Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15243/jdmlm.2022.101.3871

Abstract

Hydrological phenomena on the scale of a watershed are complex and may never be understood holistically. One of the innovations in baseflow hydrological modelling is the analysis of the baseflow recession curve, generally expressed as the natural storage of river flows and containing valuable information about the properties and characteristics of natural aquifer storage. This study aims to model land use change and baseflow recession in the Wuryantoro watershed, Wonogiri Regency, Central Java Province. The research method uses an exponential model in which changes in the characteristics of a baseflow recession are a function of land use changes over a certain period. The calibration of the seven graphical models of land use change against the characteristics of the baseflow recession shows that the seven curves of the land use change graphic model have model coefficients and curve slopes that vary from gentle to steep. The slope of the gentle and steep curve describes the bottom flow deposits' condition over time. The state of water storage in the seven better graphical models is that the change of forest remains forest followed by the change of agriculture into the forest, forest into the settlement, change of agricultural land into the settlement, change of forest to agricultural land, settlement remains settlement and change of agricultural land remains agrarian land.