Gunungsewu Karst Area Research Articles

A comparison of lineament and fracture trace extraction from LANDSAT ETM+ panchromatic band and panchromatic aerial photograph in Gunungsewu karst area, Java-Indonesia

This paper aims at exploring interpretability of the panchromatic band of Landsat Enhanced Thematic Mapper Plus (ETM+) compared to the panchromatic aerial photograph in lineament and fracture trace extraction. Special interest is addressed to karst terrain where lineaments and fracture traces are expressed by aligned valleys and closed depressions. The study area is an single aerial photographic coverage in the Gunungsewu Karst, Java-Indonesia which is characterized by a lineament-controlled cone karst and labyrinth-cone karst. The result shows that the recording time of the Landsat ETM+ with respect to the shadow resulting from the sun illumination angle is the key factor in the performance of lineament and fracture traces extraction. Directional filtering and slicing techniques significantly enhance the lineament interpretability of the panchromatic band of Landsat ETM+. The two methods result in more lineaments and fracture traces which T-test affirm in 0.001 and 0.004 significant levels. Length based lineament analysis attains a better result compared to frequency based analysis.

Primeval Forest in the Period of Human Cultural History on Gunungsewu Karst Indonesia

This research was carried out to seek evidence of the presence of karst forestduring the human cultural history in Gunungsewu in the past.The human cultural history approach and pollen deposit analysis were used for findingthe relationshipbetweenhuman cultureswith thecondition of the forest in the past. The lawuniformity was usedas a basis foranalysis,whichexplainsthatthe presentis the keytothe past. The ancient karst forest was identified frompollen deposition andthe age of deposit was carriedout byradiocarbonanalysis.Thisresearchcontributesto reach forest resources sustainability with respect to recent increasing forest depressiondue toanthropogenic factors.Research indicates that at prehistoric human occupations in the Gunungsewu karst area did not affect the condition of flora. Cultural traits onprehistoric and territorial subsistencecan explain that it is not anthropogenic factors that caused changes in the types of flora.Sincethere was noculture ofexploitation, the extraction of natural resourceswas justperformed tomeet their subsistence. Changes inthe type offlorain the past becomea bio-indicatorof palaeo-climate change on Gunungsewu Karst area. The beginning of forest karst destruction occurs in the periods of Islamicempireandcolonialism, which are known as tenure systems of migration and exploitation of teak by Colonizers.Results of the forest reconstruction along the human prehistory indicated that the lower mountainrain-forestoccurred on Keplek period, then the mixed type of lower mountain rainforest and tropical rain-forest occurred on the period of Ngrijangan. In the period of Klepu, the forest type turn into the type of tropical rainforest. Monsoon is the last forest type of residents in the human history since the Hinduism and Buddhism period up to the present.

Climate Change and Water Scarcity Adaptation Strategies in the Area of Pacitan, Java Indonesia

The Karst area in Indonesia consists of a total area of 154.000 km2 of which 15% is protected. Pacitan is a part of The Thousand Mountains (Gunung Sewu in Javanese language) karst area and located in Southern Coastal of Java Island. Gunung Sewu karst area ranges over 85km from west in Yogyakarta Special Province, to the east in East Java Province. Water scarcity is one of the issues in Pacitan due to the porous texture of the karst underground; most of the precipitation trickles immediately down into extensive system of sinkholes and caves. Thus, no surface water rivers, brooks or springs can be found in the area, especially during dry season where water supply, such as little lakes, called telaga, are depleted. Three sub-districts of Pacitan that include in Gunung Sewu karst area, i. e. Donorojo, Punung, and Pringkuku, suffer water shortage, especially during dry season, where the local communities need to walk up to 5 kilometers in order to take water for their domestic use. However, State-owned Water Company (Perusahaan Daerah Air Minum/PDAM) that has developed since 1992 in Pacitan, contributes in water supply in these areas and it has covered 70% in three kecamatan (sub-districts) by building IPA and is currently developing to cover the rest of the area by utilizing big water sources. PDAM and The Ministry of Public Work support the water treatment installation (Instalasi Pengolahan Air/IPA), especially in these three sub-districts. Furthermore, adaptive capacity has been developed in the local community of karst area in Pacitan, e.g. planting cultivars resistant to drought (cassava, maize, soybean, and groundnut) or doing multi cropping between those cultivars, and planting rainwater harvesting and artificial aquifer.

SEBARAN GUA ARKEOLOGIS DI KECAMATAN PALIYAN KABUPATEN GUNUNGKIDUL DENGAN MENGGUNAKAN ANALISIS TETANGGA TERDEKAT (NEAREST NEIGHBOURHOOD ANALYSIS)

Gunung Sewu karst area has attracted the attention archaeologists since the Dutch colonial era to the present. One of the karst area is located Paliyan District, Gunungkidul Regency. Based on research conducted by Harry Octavianus Sofian in year 2007, there were at least 11 caves and rockshelter as a potential residential dwelling. This paper will discuss and look for patterns of spatial distribution of caves and archaeological potential rockshelter as an ancient settlement in the District Paliyan using Nearest Neighbor Analysis (Analisis Tetangga Terdekat) manually and use Neighborhood Statistic analysis contained in the Arc View software.

THE DISTRIBUTION OF FLOOD HYDROGRAPH RECESSION CONSTANT FOR CHARACTERIZATION OF KARST SPRING AND UNDERGROUND RIVER FLOW COMPONENTS RELEASING WITHIN GUNUNG SEWU KARST REGION

This research is carried out within two caves with underground river and one karst spring, which is located in Gunung Sewu karst area, Gunung Kidul. The objective of this research is to recognize some flood hydrograph properties of karst aquifer characterization in order to compare the comportment of aquifer to release its flow components between underground river and karst spring. Water level data loggers are installed within two caves and one karst spring represent upper, middle, and lower elevation of karst topography, which are Beton, Seropan, and Toto Cave, respectively. In addition, time series discharge measurement in correspond to minimum, average, and maximum flow events is conducted to formulate the Annual Stage Discharge Rating Curve. Thereby, the full year river hydrograph may be defined. Afterwards, by selecting several flood hydrograph events, the recession constant in each cave including diffuse flow (Kb), and fissure flow (Ki), and conduit flow (Kc) recession constant, is then calculated and compared in every location. The result shows that Beton Spring that represents the upper part of research area confirms the quickest respond towards rainfall events. Also, this point specifies the medium number of diffuse recession constant (Kb=0.983), compared to Seropan (0.996), and Toto (0.937), means that the aquifer surrounding Toto Cave release its groundwater storage faster than Beton Spring and Seropan Cave. On the contrary, Seropan Cave performs the highest value of diffuse recession constant (0.996) and this situation is confirmed by its dry season discharge that still above 810 lt/second.

Fractal analysis of the Oyo River, cave systems, and topography of the Gunungsewu karst area, central Java, Indonesia

Fractal analysis of the Oyo River, cave systems, and topography of the Gunungsewu karst area, central Java, Indonesia

Fractal analysis of the Oyo River, cave systems, and topography of the Gunungsewu karst area, central Java, Indonesia

Gunungsewu, the southernmost subzone of the Southern Mountains, central Java, is a classic karst terrain, bounded by the Oyo River on the north and the Indian Ocean on the south. In this study, the Oyo River, the main drainage in the area, is divided into 14 segments, and the fractal dimension of each segment is determined by the box-counting method. The 14 segments show various values of fractal dimensions, which are controlled by lithology and geologic structures of the area that is being dissected by the river. Easily eroded lithologies have larger fractal dimensions, and the value changes abruptly when the river crosses faults. Fractal dimensions of six underground rivers in the Bribin, Sodong, Semuluh, Jomblang, Soga, and Sumurup caves, and the surface topography above the caves were also determined. The caves have fractal dimensions that range from 1.043 ±0.01 to 1.08±0.01; the surface topography has fractal dimensions that range from 1.49±0.01 to 1.732±0.01. The fractal dimension of an underground river is proportional to the fractal dimension of the surface topography over the passage. Larger fractal dimensions of underground rivers are associated with smaller flow rates of the rivers.