APLIKASI NERACA AIR UNTUK MENENTUKAN BULAN BASAH DAN KERING DI KOTA PALEMBANG

Ketersediaan air di suatu wilayah dapat digambarkan dengan analisis neraca air. Prinsip analisis ini berdasarkan ketersediaan air hujan setelah dikurangi kehilangan air dari proses evapotranspirasi. Berdasarkan deskripsi tersebut, studi ini bertujuan untuk menentukan bulan basah dan kering di Kota Palembang menggunakan analisis neraca air dari data curah hujan dan evapotranspirasi. Studi ini menggunakan data selama 10 tahun terakhir (2010-2019) diperoleh dari dua stasiun Badan Meteorologi, Klimatologi, dan Geofisika (Kenten dan Sultan Mahmud Badaruddin II) di Kota Palembang. Proyeksi nilai evapotranspirasi menggunakan model Penman-Monteith. Tahapan analisis meliputi akumulasi dan polinomial orde 6, penurunan, dan pengurangan dari curah hujan dan evapotranspirasi. Hasil analisis data iklim dari stasiun Kenten menunjukkan rata-rata bulan basah dalam 10 tahun terakhir terjadi pada 1-166 dan 273-365 J-day, sedangkan bulan kering terjadi pada 167-272 J-day. Analisis data iklim dari Stasiun Sultan Mahmud Badaruddin II menunjukkan bulan basah terjadi pada 1-161 dan 284-365 J-day, sedangkan bulan kering tejadi pada 162-283 J-day. Analisis data dari stasiun Sultan Mahmud Badaruddin II menunjukkan waktu bulan basah yang lebih pendek dan bulan kering yang lebih panjang 15 hari dibanding Stasiun Kenten. Namun, kedua hasil dari stasiun tersebut menunjukkan bahwa bulan basah di Kota Palembang terjadi pada awal Januari hingga pertengahan Juni dan awal Oktober hingga akhir Desember, sedangkan bulan kering terjadi pada pertengahan Juni hingga awal Oktober

Pemetaan Banjir Menggunakan HEC–RAS pada Kebun Pisang PT Agro Prima Sejahtera di Sekampung Udik, Lampung Timur

Banjir dapat berupa genangan seperti pada lahan pertanian, permukiman, dan pusat kota. Tujuan penelitian ini adalah pemetaan luas sebaran wilayah banjir yang terdapat di lahan perkebunan milik PT Agro Prima Sejahtera di DAS Way Sekampung menggunakan aplikasi ArcGIS dan HEC-RAS, hasil berupa peta wilayah sebaran banjir. Manfaat hasil penelitian ini yaitu memberikan informasi terhadap pemerintah daerah, mengenai daerah yang rawan banjir sebagai bahan pertimbangan untuk menyusun rencana pengelolaan DAS. Debit hidrograf didapat dari hasil simulasi pada aplikasi SWAT. Debit puncak sebesar 97.90 m3/detik terjadi pada 6 Oktober 2007, debit minimum sebesar 19.25 m3/detik terjadi pada 14 November 2007, dan rata – rata debit sebesar 41.14 m3/detik. Penampang saluran berbentuk trapesium dengan luas 178.52 m2, elevasi per segmen 0.5 m, lebar dasar saluran 9.1 m, dan tinggi muka air di saluran 6.23 m. Tinggi saluran 5 m dan tinggi banjir yang terjadi pada saluran saat kondisi maksimum adalah 2.17 m. Nilai koefisien manning yang digunakan sebesar 0.025 dengan tipe saluran tanah berkelok, landai, dan berumput. Luas sebaran wilayah banjir saat debit maksimum 32.48 m2 sedangkan ketika kondisi minimum 0.001 m2  dan terjadi pada hulu sungai

Analisis Potensi Kelongsoran pada Ruas Jalan Raya Pangalengan menggunakan Sistem Informasi Geografis

Indonesian National Board for Disaster Management (BNPB) claimed the landslide incident on 5 May 2015 in Pangalengan District caused gas pipelines owned by PT. Geothermal Star Energy exploded, 9 people died, 154 displaced and 10 houses buried. Based on the facts, it is necessary to make an effort to reduce the risk of landslides by utilizing satellite imagery. The purpose of this study was to identify potential landslides on the Pangalengan highway and make recommendations mitigation actions for the local government. The method used was using 2 estimation system models made by the Directorate of Volcanology and Geological Disaster Mitigation in 2004 and 2005. The result of the DVMBG 2004 showed the very high classification had a percentage of 97.24% and the DVMBG 2005 result showed the high classification reached 53.26% and the very high classification reached 53.26%. The potential for landslides on the Pangalengan road is 98.37%. Recommended mitigation actions were cutting slopes or making soil retaining walls or drainage channel planning

Weed Control Decision Support System Based on Precision Agriculture Approach

Herbicides have been widely used for weed control in modern agriculture. However the use of herbicides is potentialy introducing negative impact to the environment due to excessive use of herbicides. Based on precision agriculture principles, unique and precise treatment of herbicide supply for a particular area for crop production must be performed. The objective of this research is to develop a decision support system (DSS) for schedulling of weed spraying and for selecting the proper nozzle size of the sprayers that introduce minimum negative impact to the environment. The main set of data required for our proposed system includes the set of 10 years weather data series acquired from remote sensing (NOAA and TRMM) and a set of vegetation index from MODIS EVI. The weather data set is utilized to determine the planting time period of paddy crop and to determine the proper size of the sprayers for weed spraying. Our DSS prototype has been implemented and tested with real data set in Jonggol district, West Java, Indonesia. The implementation, testing results, and future enhancement of our system are discussed in this paper

Analisis Debit Air Dan Airtanah Dangkal Daerah Aliran Sungai (DAS) Prumpung, Kabupaten Tuban

The water demand increases in line with the growths of population, industry and business, but the water availability is ascertained to satisfy those needs continuously. Therefore, it is necessary to analyze water availability in a specified watershed integrated with various aspects in hydrology. The objective of this study were (1) to identify of landuse at Prumpung watershed,(2) to determine water availability in Prumpung watershed by analyzing the relationship of rainfall and river discharge using the Soil and Water Assessment Tool (SWAT) and (3) to influence government policies relation with urban planning of Tuban Regency. The watershed is located in Tuban Regency and based on urban planning of Tuban Regency 2012-2032 which is covering 22,319.14 ha. Input data were Digital Elevation Models, land use, and soil map. The procedures were including collection and process of climate data, trend analysis of water availability, discharge measurements, discharge analyze and calibration using SWAT. The results of existing landuse showed that the minimum water discharge was 0.338 m3/s to the maximum 5,945 m3/s with groundwater availability was maximum until 3,070 mm on July to September 2014. SWAT has generated 27 HRUs that described the spatial condition of the whole watershed. Calculated discharges with SWAT compared to the measured discharges having The NashSutcliffe Efficiency (NSE) of 0.77 and correlation coefficient of 0.79. Conservation scenario has been conducted at several landuses for water availability and based on conservation area. The results showed that the minimum water discharge was 0.334m3/s to the maximum 4.842 m3/s with groundwater availability was maximum until 3,140 mm. There were no significant change of groundwater based on urban planning and scenario at Prumpung watershed, Tuban Regency.Identification of Prumpung watershed produced relatively small water discharge compared than water demand based urban planning of Tuban Regency. A plan of water management for exploiting of high rain fall in rainy season will contribute in consideration of the appropriate water supply/demand balance in dry season

Analisis Curah Hujan dan Debit Model Swat dengan Metode Moving Average di DAS Ciliwung Hulu

Watershed can be regarded as a hydrological system that has a function in transforming rainwater as an input into outputs such as flow and sediment. The transformation of inputs into outputs has specific forms and properties. The transformation involves many processes, including processes occurred on the surface of the land, river basins, in soil and aquifer. This study aimed to apply the SWAT model in Ciliwung Hulu Watershed, asses the effect of average rainfall on 3 days, 5 days, 7 days and 10 days of the hydrological characteristics in Ciliwung Hulu Watershed. The correlation coefficient (r) between rainfall and discharge was positive, it indicated that there was an unidirectional relationship between rainfall and discharge in the upstream, midstream and downstream of the watershed. The upper limit ratio of discharge had a downward trend from upstream to downstream, while the lower limit ratio of discharge had an upward trend from upstream to downstream. It showed that the discharge peak in Ciliwung Hulu Watershed from upstream to downstream had a downward trend while the baseflow from upstream to downstream had an upward trend. It showed that the upstream of Ciliwung Hulu Watershed had the highest ratio of discharge peak and baseflow so it needs the soil and water conservations and technical civil measures. The discussion concluded that the SWAT model could be well applied in Ciliwung Hulu Watershed, the most affecting average rainfall on the hydrological characteristics was the average rainfall of 10 days. On average rainfall of 10 days, all components had contributed maximally for river discharge

DEVELOPING TOURING PLAN USING GEOGRAPHIC INFORMATION SYSTEM BASED ON VISUAL, NATURAL, AND CULTURAL QUALITIES IN PARANGTRITIS COASTAL AREA, YOGYAKARTA, INDONESIA

The objectives of this study is studying on developing touring plan in coastal area of Parangtritis based on its visual, natural,  and cultural quality assessment. Those three aspects of quality are used as the basic consideration for site assessment in acquiring the potential tourism area, which is subsequently used in developing a touring system.Scenic Beauty Estimation (SBE) method and visual character variables assessment are used in assessing the visual quality of the study area. The technique of potential zones mapping applied by Gunn (1994) combined with cartographic regionalization (Smith, 1989) are used in assessing both natural and cultural quality of the area.In general, Parangtritis is dominated with high to  medium quality of potential area for tourism, which includes beach, sand dunes, woodlands, and a big part of agriculture area. Based on potential area and existing tourism objects, there are three track alternatives that have been developed in this study by using the concept of developing an interpretive track, as adopted from Damayanti (2003).According to the prioritizing process using Analytical Hierarchy Process (AHP), the third alternative of touring plan, whichhas the highest priority for the criteria of educational benefits, is perceived  to be the most preferable alternative as the potential tourism network in Parangtritis Coastal Area

Simulation of the impact of land use change on surface run-off in Karst Leang Lonrong Sub-Watershed

Estimation of surface run-off in karst watersheds has not been widely carried out and the estimation method is generally developed for non-karst watersheds. This study aims to analyze the accuracy of estimation of river discharge at the outlet of the Karst Biringere Sub-watershed using the modified Soil Conservation Service Curve Number (SCS-CN) method and analyzed the impact of land use change on river discharge at the outlet of the Karst Biringere Sub-watershed. Modification of the SCS-CN method in estimating direct flow at the outlet of the Beringere Sub-watershed is influenced by the similarity of rainfall and direct flow fluctuation of river discharge. The modified SCS-CN method provides satisfactory direct flow estimation when rainfall with observed direct flow of river discharge forms a linear relationship with a strong correlation. Changes in land use with reduced forest cover into mining areas result in increased run-off and reduced storage, the larger the forest land becomes mining areas, the greater the increase in run-off and reduction in storage. Reclamation of the former mining area to be a forest reduces run-off and increases water storage

Internet Based Expert System for Hand Tractor Trouble Shooting

The final step of this research was uploading the system in virtual FTP (File Transfer Protocol directory address /www/smipipb, and Uniform Resource Locator (URL) to access this site washttp://www.websamba.com/smipipb. The eveluation using the same browser engines indicutes that the system work as weN as in the local intranet. The knowledge base contains rules concerning the knowledge domain transformed and stored in the Microsoft Access data basejle. The main constribution of this research is to provide a multiuser software tool for hand tractor trouble shooting in the internet environment

Effects of Soil Moisture Content on Groundwater Electrical Resistivity Values in Irrigation Paddy Scheme, Tanjong Karang, Malaysia

Electrical Resistivity Tomography (ERT) analyses have been conducted in Irrigation Paddy Scheme, Tanjong Karang, Malaysia as part of investigation on groundwater potential aquifer to provide an alternative water resource for paddy irrigation. Based on recent studies on groundwater resistivity in paddy field, irrigation system mentioned as soil moisture content was observed to affect the value of electrical resistivity and subsurface geological profile resulted from ERT analysis. The objective of this study was to proof any correlation between soil moisture content and electrical resistivity values and to determine at what level of soil moisture content which will be the best condition to conduct ERT survey. ERT analysis was conducted by using ABEM Terrameter SAS 4000 of Wenner-Schlumberger array with 5.0 meter and 10.0 meter for minimum and maximum electrode spacing. Visually, based on subsurface geological profile resulted from ERT analysis soil moisture content affected (changed) electrical resistivity values. With all different treatments of soil moisture ranged from 16.96% to 27.50%, electrical resistivity values decreased in certain points and in certain depth along with the increase of soil moisture content. This was proofed by ANOVA and Duncan’s multiple range tests showing that Pr > F value was less than 0.0001. Further on Chi-square test showed that at soil moisture level of 22.54%, it was the best condition which gave more correct counts of electrical resistivity values compared to well lithology. This was assumed to be the best condition to conduct ERT survey