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Community Based Warning and Evacuation System against Debris Flow in the Upper Jeneberang River, Gowa, South Sulawesi
Get PDFGigantic collapse of the Caldera wall of Mt. Bawakaraeng (2,830 m) in March 2004 had supplied the sediment volume of 230 million to the most upper stream of Jeneberang River, which flowed down to the lower reach in the form of debris flow which is triggered by rainfall. The purpose of the research is to provide a system which is able to forecast the occurrence of debris flow, to identify the weak points along the river course, to identify the hazard areas and how to inform effectively and efficiently the warning messages to the inhabitants in the dangerous area by using the existing modern equipment combined with the traditional one. The standard rainfall which is used to judge the occurrence of debris flow was established by Yano method. It is based on the historical data of rainfall that trigger and not trigger to the occurrence of debris flow which is widely used in Japan so far. The hazard area was estimated by Two-Dimensional Simulation Model for debris flow, the debris flow arrival time at each point in the river were estimated by dividing their distance from reference point by debris flow velocity, where the check dam no. 7-1 in Manimbahoi was designated as reference point. The existing evacuation routes were checked by field survey, the strength and coverage of sound for kentongan and manual siren were examined using sound pressure level at the location of the existing monitoring post and the effectiveness of warning and evacuation were evaluated by comparing the warning and evacuation time against the debris flow arrival time. It was resulted that debris flow occurrence was triggered by short duration of high rainfall intensity, long duration of low rainfall intensity and the outbreak of natural dam which is formed by land slide or bank collapses. The hazard area of upper Jeneberang River are mostly located on the river terraces where the local inhabitants earn their living through cultivating the river terraces as paddy fields, dry field and sand mining. It was also resulted that at the elevation of 700 m to the upper stream, the arrival time of debris flow is too short ( 3 minutes), it means that there is no time to evacuate when debris flow occurs. There are enough time to evacuate along the reaches between 700 m to 390 m and more time to evacuate along the downstream of 390 m river bed elevation due to the longer arrival time of debris flow. The existing community based warning system against debris flow uses radio transceiver to communicate between post and uses kentongan and sirens to propagate the warning message to inhabitants. Based on the sound test conducted in Jeneberang River, the manual siren has a coverage of 160 m to 600 m and it can be used in the warning system, being co-existence with the kentongan which has been used for a long time. In order to keep the community based warning system well functioned, it is recommended to synergize between the Local Government of Gowa Regency and the other stake holders with the inhabitants along Jeneberang River and the Sabo Community of Jeneberang in the operation and maintenance of the system
Pengaruh Perubahan Penggunaan Lahan terhadap Sifat Biofisik Tanah dan Kapasitas Infiltrasi di Kota Malang
Get PDFLand use management causes the changes of the function of the land in the city. The change of the function of uncultivated land to be cultivated land has a potential to change soil biophysical characteristic, and at the same time, it decreases the absorption of soil water. This research aims: (1) to study the influence of the landuse change towards soil biophysical characteristics, (2) to study the correlation between soil biophysical characteristics and infiltration capacity, and (3) to study the influence of the landuse change towards the infiltration capacity. The landuse change is studied by comparing the ongoing mapping documents. Soil biophysical characteristics consist of root biomass, number of worms, soil organic matter (SOM), and porosity. The root biomass is obtained by root density, the number of worms is identified with monolith and hand sorting method, the SOM is identified with fraction analysis, and the porosity is identified with cylinder and pignometer method. The water absorption is measured with the plot experiment. The influence of the landuse towards soil biophysical traits is analyzed T-test and the influence of landuse change towards infiltration capacity is analyzed correlatively. This research gains the results that: (1) the landuse change causes the change of soil biophysical traits, too, and the soil biophysical traits change causes, furthermore, the declining of the land capability in absorbing water, and (2) the amount of the infiltration capacity is caused by soil biophysical traits, mostly by root biomass, number of worms, and the SOM, and (3) the landuse change causes the declining of infiltration capacity
Kajian Model Estimasi Volume Limpasan Permukaan, Debit Puncak Aliran, dan Erosi Tanah dengan Model Soil Conservation Service (SCS), Rasional Dan Modified Universal Soil Loss Equation (MUSLE) (Studi Kasus di DAS Keduang, Wonogiri)
Get PDFHydrologic modelling has been developing and it is usefull for basic data in managing water resources. The aim of the reseach is to estimate volume runoff, maximum discharge, and soil erosion with SCS, Rational, and MUSLE models on Keduang Watershed. Explain the data analysis, and flow to get the data. SCS parameters model use are: runoff, rainfall, deferent between rainfall runoff. The deferent rainfall between runoff relationship kurva Runoff Coefisient (Curve Nunmber/CN). This Coefisient connected with Soil Hydrology Group (antecedent moisture content/AMC), landuse, and cultivation method. Rational parameters model use are: runoff coefisient, soil type, slope, land cover, rainfall intensity, and watershed areas. MUSLE parameters model use are: rainfall erosifity (RM), soil erodibility (K), slope length (L), slope (S), land cover (C), and soil conservation practice (P). The result shows that the conservation service models be applied Keduang Watershed, Wonogiri is over estimed abaut 29.54 %, Rational model is over estimed abaut 49.96 %, and MUSLE model is over estimed abaut 48.47 %
The Influence of Spatial Urbanization to Regional Condition in Periurban Areas of Yogyakarta
Get PDFIt is interesting to study periurban areas because of its transitional characteristic. Periurban areas undergo dynamic changes as a result of spatial urbanization. This study is aimed at: (1) examining the development pattern of spatial urbanization in Yogyakarta and finding out the influential determinant factors; (2) examining the dynamics of land use changes in periurban areas and finding out the resultant impacts; (3) examining the pattern and development of services (infrastructures) and finding out the determinant factors supporting the development of services (infrastructures) in periurban areas; (4) examining the role of the development of periurban services (infrastructures) as magnetic forces for periurban development; and (5) making policies concerning periurban development and management in order to achieve optimal development and to balance the functions of urban and rural areas. The methods used in this research are secondary data analyses and aerial photo interpretation. This study applies secondary data analysis by comparing the data to find out the extent of the changes. Descriptive statistics, scaling, and discri-minant analysis are used as the analytical techniques to find out the determinant factors of urban growth in periurban areas. Spatially, urbanization in Yogyakarta periurban areas tends to move toward the western part (Ngestiharjo village), northern part (Catur Tunggal village) and eastern part (Banguntapan village). Besides centrifugal forces, the development of built land and urban characteristics in the western, northern and eastern parts are also influenced by the main roads (corridors) from Yogyakarta to Kaliurang, from Yogyakarta to Wates, and from Yogyakarta to Solo. The existence of the corridors prompts the functions of trade and services which, in turn, trigger the development of the surrounding housing complex. On the contrary, in the southern and south-east part of Yogyakarta the activities of service have not yet well-developed and neither have the new housing complex. The development of number and density population are variables determining urban development in Yogyakarta periurban areas. The dynamics of land use changes in Yogyakarta periurban areas are characterized by the decrease in agricultural land (6.46 % per year) and the increase in built land. The decrease in agricultural land reduces the sustainability of agricultural environment. Agricultural production can no longer satisfy periurban people’s needs for food. The different strength in interaction results in the difference in the facilities of service (infrastructure) between periurban areas. The periurban dynamics in Yogyakarta are also characterized by the increase in function and sustainability of services. The development of service (infrastructure) in Yogyakarta periurban areas have a lot of impacts especially those related to the increase in urban characteristics. In some parts of periurban areas, there is a relation between the increase in service provision and the development of urban characteristics
Development and Environmental Resources Conservation
No full textDevelopment is a certain coveted by all people in which included the natural resource development of living members, because a large part of human necessity is supplied by the natural resource. Thus, the more population the more necessities of the natural resource consumed. Natural resource availability is limited while the development is in progress. In such condition the resource is getting decrease and finally destroyed, unless we develop its and make a provision in replacement. Acording to what is said by, it is needed a human knowledge about environmental concept of living members in order that in the desired development realization an environmental conservation will be protected permanently
Leather Industry Business Linkages (Case Study in District Magetan)
No full textLeather industry in Magetan covers two forms; they are tanning and leathercraft. During 1960 and 1970, the leather industry decreased in its production, but in 1990 Magetan becomes the center of leather industry. Its development appeals to be studied closely. The goals of this study are to know the relation between tanning and leathercraft, the connection between these industries and other economic ativities, and their connection with production factor. This study uses survey methhod. The respondents are taken proportionally from both of those leather industries. The data is obtained inetrviewing the respondents with questionnaire that related to the input and out put of the industry. The result of this study shows that there is no relationship between the kind of industries (small and household industry) and its capital, especially in its raw material (44,44%). The relationship between tanning and leathercraft is low, because it is only 24,2% input of leathercraft which taken from output of tanning. The region relationship for tanning is larger, because the products that are sold to other regions are 97,22% for tanning and 68,29% for leathercraft. Its relationship to other sectors especially for labour supply is 56,48% from farming and trade sectors in marketing
Industrial Water Waste, Problems and the Solution
No full textRecently, the long term development in Indonesia has changed agricultural sector to the industrial sector. This development can apparently harm our own people. This is due to the waste that is produced from factories. The waste from various factories seems to have different characteristics. This defference encourages us to be able to find out different of methods of managing waste so that cost can be reduced, especially in water treatment. In order that industrial development and environmental preservation can run together in balance, many institutions involved should be consider, especially in the industrial chain, the environment, and human resource, these three elements can be examined in terms of their tolerance to waste
Consumption of Water for Household Needs and the Affecting Factors at Banyudono Boyolali
No full textThe consumption of drinking water for a community is different from one area to the other. This is normally influenced by the population development, socio-economic, cultural, and physical conditions mainly related to the supply of drinking water and how to exploit it. Banyudono district is an area located in the regency of Boyolali. The development of this area depends on Boyolali City and Kartasura district. Such a location enables the area to have a process of the physical and socio-economi developments. In addition, it has an influence upon social behaviour to consume water. This research is aimed at knowing the average consumption of household need and analyzing the factors influencing the utilization of water as drinking water. The result of this research indicated that 1) the average consumption of a human being for drinking water was 79,37 litter a day. It means that the onsumption of a human being for drinking ater generally ranged from 60 to 80 litter a day; 2) most of the ater was consumed to meet basic needs such as cooking, drinking, bathing, and washing; 3) the difference of the average consumption was influenced by the kind of water source and how to exploit it; 4) a parameter of the most significant socio-economic condition that took effect on the average consumption for drinking water was the parameter of income with correlation of 0.362 and the significant level of 0.01
Geomorphic Hazard Map for Spatial Planning Purposes
No full textIn the planning of spatial lay-out oriented to environmental concept, it requires the information input conneting with the condition of local environment. This condition constitutes the features characteristic of the living space which consist of natural and social environment. One of the natural environment elements, neede to the spatial lay-out planning, is the dynamis geomorphology. The process of the dynami is some times accelerated and increased by natural and anthropogenic factors. The abnormality in both acceleration and the increase will cause a natural disaster, which is based on the landscape approach it is called the geomorphologic hazard. In connection with such event thematic map of geomorphologic hazard describes the disaster susceptibility of an area. The geomorphologic hazard map is an output map whose information is obtainable from thematic map conneting with population, land use, topography, geomorphology, rainfall, hydrological data, and slope classification. Both land use and population maps desccribes the anthropogenic factors. The role of the geomorphologic hazard map, in the planning of spatial lay-out and environmental management, i.e. preventive, represive, rehabilitative, and serves as the basis for interpretation and management of living spere. By putting geomorphologic hazard into map compilation of spatial lay-out (cultural and non cultural area map) a footstep advance is the reached to guarantee human security and their treasures, and human well-being as an integral part of human living prosperity
Statistical Quantification for Supporting Geographical Research in Natural Resource Inventory and Evaluation
No full textIn supporting geographical researches, statistical quantifications are required to assist natural resources inventory and evaluation. Statistical analysis for any research either in sciences will represent the result quality of the research. To do this, all research system implementations. Started from data collection, process to their presentation need to apply quantitative statistics data and numbers. This paper is meant as introducing all geography researchers in conducting researh tasks, particularly in the field natural resources inventory and evaluation