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EVALUATION OF WATER QUALITY USING POLLUTION INDEX IN CIMANUK WATERSHED, INDONESIA Nurrohman, Andy Wibawa; Widyastuti, M.; Suprayogi, Slamet
ECOTROPHIC : Jurnal Ilmu Lingkungan (Journal of Environmental Science) Vol 13 No 1 (2019)
Publisher : Master Program of Environmental Science, Postgraduate Program of Udayana University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (612.395 KB) | DOI: 10.24843/EJES.2019.v13.i01.p08

Abstract

Land use is one of the macro parameters that affects water quality in a watershed. The Cimanuk watershed which is dominated by agricultural land use and settlements has encountered a decline in water quality. There are eight parameters including pH, TDS, TSS, Nitrate, Phosphate, Sulphate, BOD, and COD analyzed to evaluate water quality utilizing the Pollution Index (IP) method. This research has provided a clear understanding of the status of water quality in the Cimanuk watershed based on six monitoring points carried out at the start of the 2018 rainy season. Overall, the IP values obtained ranged from 2.05 to 5.96 with the lightly polluted category at points A, B, C, D, and E, while for point F it was in the moderately polluted category. The key parameters that have the most influence on water quality pollution are Nitrate, Phosphate, Sulphate from fertilization activities in agricultural land, while runoff from settlements contribute to increasing parameters of  BOD and COD. These results can be beneficial for sustainable management of water and land resources in the Cimanuk watershed.
KONSERVASI MATA AIR BERBASIS MASYARAKAT DI UNIT FISIOGRAFI PEGUNUNGAN BATURAGUNG, LEDOK WONOSARI DAN PERBUKITAN KARST GUNUNG SEWU, KABUPATEN GUNUNGKIDUL Sudarmadji, Sudarmadji; Suprayogi, Slamet; Widyastuti, M.; Harini, Rika
Jurnal Teknosains Vol. 1 No. 1 tahun 2011
Publisher : Sekolah Pascasarjana UGM

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Abstract

Spring is as one of the water resources potential that can not be ignored. Gunungkidul district has three physiographic units: Baturagung Hills, Wonosari Basin and Gunung Sewu Karst Hills. All of them affect the distribution of springs in the Gunungkidul Regency. On the other hand, physiography will affect the community adaptation to the environment. It will contribute to the springs conservation effort. The purposes of this research are:  1) to identify the characteristics of springs, 2) to analyze the community participation in conserving  the springs as basic information to develop spring conservation models. To identify the socio-economic characteristics and the springs characteristics in the research areas use a survey method. Unit sampling and analysis is done purposively based on three zones: Baturagung Hills, Wonosari Basin and Gunung Sewu Karst Hills. Socio-economic survey was done by sampling on the 90 respondents, divided into 3 zones through direct interviews using quetionare. Quantitative descriptive analysis was performed through statistical tests. The results show that the quality of spring water in all physiographic zones meet to the water quality standard, except those for colli bacteria. The discharge of karst springs in the hills of Gunung Sewu greater than the discharge of the two other zones. The springs distribution is more in Wonosari Basin and Karst Hills of Gunung Sewu than Baturagung Hills. The level of the community participation in springs conservation is mostly done in groups through user spring groups. Generally, socio-economic factors affect to the level of participation in prevention of springs damage.
URBAN SEDIMENT IN INFILTRATION WELLS: A LESSON FROM THE NORTHERN AREA OF GREATER YOGYAKARTA CITY Suprayogi, Slamet; Sudarmadji, Sudarmadji; Malawani, Muhammad Ngainul
Indonesian Journal of Geography Vol 51, No 3 (2019): Indonesian Journal of Geography
Publisher : Faculty of Geography, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5890.254 KB) | DOI: 10.22146/ijg.33721

Abstract

The development of housing in Yogyakarta eventually led to increased levels of runoff. To mitigate runoff increases, infiltration wells were constructed in a specific network. The northern part of Yogyakarta is now facing urbanization, and there are many housing blocks that are being constructed complete with the runoff drainage system. This study aims to reveal the role of the infiltration wells network about runoff and its effectiveness concerning the sediment load in the urban area. The drainage networks in the research area function as a watershed, but not with a single outlet. The runoff flow was spreading through the drainage system and did not accumulate on the single outlet. It can be seen that some infiltration wells supposed as a well, which is a place of accumulation of runoff and sediment.  Most of the infiltration wells have been filled with sediment up to over a quarter, or even more than half, of their carrying volume. Granulometry measurement shows that the percentage of clay, loam, sand, and gravel in each well tend to differ for every sample. The differences between filled wells and their sediment grain depend on the location of those wells. Maintenance of the wells is required, such as sediment dredging, to rejuvenate them and improve their efficiency.
SUITABLE PROPORTION SAMPLE OF HOLDOUT VALIDATION FOR SPATIAL RAINFALL INTERPOLATION IN SURROUNDING THE MAKASSAR STRAIT Giarno, Giarno; Hadi, Muhammad Pramono; Suprayogi, Slamet; Murti, Sigit Heru
Forum Geografi Vol 33, No 2 (2019): December 2019
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/forgeo.v33i2.8351

Abstract

Spatial rainfall interpolation requires a number of suitable validation samples to maintain accuracy. Generally, the larger the areas which can be predicted, the better the interpolation. In addition, the data used for validation should be separated from the modelling data. Moreover, the number of samples determine optimally proportion the independent sites. The objective of this study is to determine the optimal sample ratio for holdout validation in interpolation methods; the Makassar Strait was chosen as the study location because of its daily rainfall variation. The accuracy of the sample selection is tested using correlation, root mean square error (RMSE), mean absolute error (MAE) and the indicators of contingency tables. The results show that accuracy depends on the ratio of the modelling data. Therefore, the more extensive the data used for interpolation, the better the accuracy. Otherwise, if the rain gauge data is separated according to province, there will be a variation in accuracy in the portion of independent samples. For rainfall interpolation, it is recommended to use a minimum 75% of data sites to maintain accuracy. Comparison between kriging and inverse distance weighting or IDW methods indicates that IDW is better. Moreover, rainfall characteristics affect the accuracy and portion of the independent sample.
ESTIMASI EVAPOTRANSPIRASI POTENSIAL MENGGUNAKAN JARINGAN SYARAF TIRUAN Suprayogi, Slamet; Setiawan, Budi Indra; Suroso, Suroso Suroso
Majalah Geografi Indonesia Vol 18, No 1 (2004): Maret 2004
Publisher : Fakultas Geografi, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (342.549 KB) | DOI: 10.22146/mgi.13265

Abstract

ABSTRAK Berbagai model evapotranspirasi potensial (ETp) telah dikembangkan, mulai dart model-model yang sederhana sampai dengan model-model yang kompleks membutuhkan konversi-konversi dan perhitungan rumit. Model ETp Penman termasuk model yang kompleks membutuhkan parameter-parameter iklim yang cukup banyalcyaitu: suhu udara, kelembaban relatif(relative humidity), kecepatan angin, tekanan uap jenuh (saturation vapor pressure), dan radiasi netto. Proses perhitungannya membutuhkan waktu relatif lama, karena harus melakukan konversi-konversi. Perhitungan ETp dapat dilalcukan secara efisien yalan proses perhitungan cukup singkat dan hasilnya secara basil perhitungan model Penman yaitu dengan model Jaringan SyarafTiruan (Artificial Neural Network), model tersebut merupakan penjabaran fungsi otak manusia (human brain) dalam bentukfungsi matematik yang menjalankan proses perhitungan secara paralel.Tujuan penelitian ini adalah mengestimasi ETp menggunakan model Jaringan Syaraf Tiruan (JST) dengan penjalaran balik (backpropagation). Data yang digunakan adalah data parameter iklim stasiun Serang tahun 1999 sid tahun 2001. Parameter iklim yang digunakan analisis adalah suhu udara, kecepatan angin, kelembaban relatif (RH), dan lama penyinaran matahari. Proses pembelajaran model Jaringan syaraf tiruan penjalaran balik menggunakan input parameter iklim dan output ETp basil perhitungan model Penman. Data training dan test adalah ETp model Penman, parameter iklim tahun 1999, dan ETp, parameter iklim tahun 2000. Verifikasi digunakan ETp, parameter iklim tahun 2001, dengan indikator kesalahn Root Mean Squared Enos (RMSE) digunakan pula koefisien determinasi (R2).Hasil training dan test data menggunakan model jaringan syaraf tiruan penjalaran balik (backpropagation) menunjukkan bahwa data tahun 1999 dan 2000 merupakan data yang representatif dengan.nilai RMSE adalah 0,00056 dan R2 adalah 0,98, sehingga data tersebut dapat mewaldli data parameter iklim stasiun Serang. Verifilcasi dilakukan dengan cara membandingkan ETp harian tahun 2001 basil perhitungan model jaringan syaraf tiruan dengan ETp harian tahun 2001 basil perhitungan model Penman. Nilai RMSE ETp harian tahun 2001 model Jaringan syaraf tiruan dengan model Penman adalah 0,3262, sedangkan koefisien determinasi (R2) adalah 0,88. Nilai tersebut menunjukkan ETp model jaringan syaraf tiruan penjalaran balik (backpropagation) mempunyai nilai yang secara dengan ETp model Penman. Dengan demikian nilaipembobot (weight) basil pembelajaran model JST dapat digunakan untuk mengestimasi ETp stasiun Serang pada tahun-tahun berilannya maupun tahun-tahun yang lalu.
Distribution of Accuracy of TRMM Daily Rainfall in Makassar Strait Giarno, G; Hadi, Muhammad Pramono; Suprayogi, Slamet; Murti, Sigit Heru
Forum Geografi Vol 32, No 1 (2018): July 2018
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/forgeo.v32i1.5774

Abstract

This research aims to evaluate rainfall estimates of satellite products in regions that have high variations of rainfall pattern. The surrounding area of Makassar Strait have chosen because of its distinctive rainfall pattern between the eastern and western parts of the Makassar Strait. For this purpose, spatial distribution of Pearson’s coefficient correlation and Root Mean Square Error (RMSE) is used to evaluate accuracy of rainfall in the eastern part of Kalimantan Island and the western part of Sulawesi Island. Moreover, we also used the contingency table to complete the parameter accuracy of the TRMM rainfall estimates. The results show that the performance of TRMM rainfall estimates varies depending on space and time. Overall, the coefficient correlation between TRMM and rain observed from no correlation was -0.06 and 0.78 from strong correlation. The best correlation is on the eastern coast of South West Sulawesi located in line with the Java Sea. While, no variation in the correlation was related to flatland such as Kalimantan Island. On the other hand, in the mountain region, the correlation of TRMM rainfall estimates and observed rainfall tend to decrease. The RMSE distribution in this region depends on the accumulation of daily rainfall. RMSE tends to be high where there are higher fluctuations of fluctuating rainfall in a location. From contingency indicators, we found that the TRMM rainfall estimates were overestimate. Generally, the absence of rainfall during the dry season contributes to improving TRMM rainfall estimates by raising accuracy (ACC) in the contingency table.
Estimation of Solar Radiation using Artificial Neural Network Suprayogi, Slamet
Forum Geografi Vol 18, No 1 (2004)
Publisher : Forum Geografi

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Abstract

The solar radiation is the most important fator affeccting evapotranspiration, the mechanism of transporting the vapor from the water surface has also a great effect. The main objectives of this study were to investigate the potential of using Artificial Neural Network (ANN) to predict solar radiation related to temperature. The three-layer backpropagation were developed, trained, and tested to forecast solar radiation for Ciriung sub Cachment. Result revealed that the ANN were able to well learn the events they were trained to recognize. Moreover, they were capable of effecctively generalize their training by predicting solar radiation for sets unseen cases.
DAMPAK TRANSFORMASI NITROGEN TERHADAP LINGKUNGAN BIOTIK DI DANAU TONDANO PROVINSI SULAWESI UTARA Wantasen, Sofia; Sudarmadji, Sudarmadji; Sugiharto, Eko; Suprayogi, Slamet
Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 19, No 2 (2012)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1.84 KB)

Abstract

Nitrogen di lingkungan akan mengalami transformasi ke dalam bentuk-bentuk senyawa antara lain nitrat (N03), nitrit (N02-), ammonia (NH3). Transformasi dari nitrogen menjadi nitrat, nitrit, dan ammonia akan berdampak negatif terhadap lingkungan biotic yaitu terbentuknya kondisi toksik, berdampak negatif pada biota air (flora akuatik), dominansi flora akuatik danau serta berubahnya fungsi ekosistern danau. Penelitian ini bertujuan untuk mengkaji dampak transformasi nitrogen terhadap Iingkungan biotik (flora akuatik) di Danau Tondano. Pengambilan sam pel kualitas air dilakukan dengan menggunakan metode composite sampling pada 24 lokasi sampel di Danau Tondano yaitu 6 sampel di bagian timur dan au, 3 sampel di bagian barat danau, 4 sampel di bagian selatan danau dan 10 sam pel di bagian tengah danau dan 1 sampel di bagian utara Danau Tondano, kemudian dilakukan pengukuran in situ untuk parameter temperatur air, dan pH. Analisis parameter nitrat, nitrit, ammonia dilakukan di Laboratorium Balai Teknik Kesehatan Lingkungan Provinsi Sulawesi Utara. Lokasi pengambilan sampel flora akuatik adalah 1 sampel di bagian barat Danau tondano (Paletoan), 4 sampel di bagian timur danau (Eris, Tasuka, Ranomerut), dan 1 sampel di bag ian utara danau (Tolour). Hasil analisis laboratorium menunjukkan bahwa transformasi nitrogen menjadi nitrat, nitrit, ammonia di permukaan Danau Tondano terkonsentrasi tinggi di bagian timur dan bagian tengah Danau Tondano. flora akuatik yang mendominasi perairan adalah Eceng Gondok ( Eichhornia crassipes) dengan Indeks Nilai Penting (INP) 60-155.
DAMPAK PENGELOLAAN LAHAN PERTANIAN TERHADAP HASIL SEDIMEN DI DAERAH ALIRAN SUNGAI GALEH KABUPATEN SEMARANG Arianti, Forita Dyah; Suratman, Suratman; Martono, Edhy; Suprayogi, Slamet
Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 19, No 3 (2012)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1.84 KB)

Abstract

Perubahan jumlah manusia dan bentuk kegiatannya akan mengakibatkan perubahan dalam pengelolaan lahan. Sistem pengelolaan lahan pertanian pada daerah aliran sungai (DAS) Galeh umumnya masih belum memperhatikan kemampuan dan kesesuaian lahan. Masyarakat yang bermukim di DAS Galeh didominansi oleh petani. Dinamika pengel laan lahan pada sistem DAS akan mempengaruhi kondisi aliran sungai, yang menyebabkan terjadi perubaban debit aliran sungai sebagai keluaran DAS, sehingga mengakibatkan perubahan dalam kualitas lingkungan. Dampak yang sering terlihat adalah terjadinya kerusakan lahan karena meningkatnya erosi tanah dan sedimentasi. Kajian ini dilakukan dari bulan Pebruari sampai bulan Juli tahun 2010 di DAS Galeh, Kabupaten Semarang dengan tujuan untuk mengetahui hasil sedimen yang diakibatkan oleh pengelolaan lahan pertanian yang berbeda di daerah aliran sungai Galeh. Kajian dilakukan dengan cara menganalisis sampel-sampel sedimen melayang (suspended sediment) yang diambil dari outlets ketiga sungai utama yang bermuara ke Sungai Galeh. Parameter-parameter yang diukur untuk keperluan analisis hasil sedimen ini, yaitu konsentrasi sedirnen melayang Cs (mg/l), debit aliran air sungai Q (m3/detik) dan debit sedimen melayang Qs (gr/detik). Dari hasil kajian tampak bahwa terdapat debit aliran yang berpengaruh terbadap debit suspensi, di mana semakin besar debit aliran maka semakin besar debit suspensi. Pengelolaan lahan sawah memiliki debit aliran dan debit suspensi yang lebih tinggi dibanding pengelolaan lahan kebun dan lahan tegalan. Sedimen yang dihasilkan pada pengelolaan lahan sawah sebesar 14,593 ton/hari; pengelolaan lahan kebun sebesar 1,308 ton/hari, pengelolaan lahan tegalan sebesar 0,718 ton/hari.
Contamination Vulnerability Analysis of Watershed for Water Quality Monitoring Widyastuti, Widyastuti; Suprayogi, Slamet
Forum Geografi Vol 20, No 1 (2006): July 2006
Publisher : Universitas Muhammadiyah Surakarta

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Abstract

This research is an early step to determine the location of rain gauge station for artificial neural network modeling. The implementation of this model is very useful for water quality monitoring. The objectives of this study are: 1) to study the distribution of watershed parameter, that are average annual precipitation, land use and land-surface slope, 2) to conduct vulnerability analysis of watershed contamination, 3) to determine the location of rain gauge station. The study was performed by weighing and rating method of watershed parameters. The vulnerability degree of watershedtocontaminationispresentedasvulnerabilityindex.Thisindexisdeterminedbyoverallsumofallmultiplication between score and weigh number of each parameter. All data manipulation and data analysis were performed by using Geographic Information System (ArcView version by 3.2). The vulnerability of watershed contamination map had been generated using overlay operation of parameters. The results show that vulnerability index are varies between 10 up to 40 intervals. Hence, the indexes were categorized into three levels of watershed vulnerability, namely low (10 – 20), moderate (20 – 30) and high (30 – 40). It is found that the study area covered more by high vulnerability of watershed to contamination. The zoning of watershed vulnerability meant to determine the rain gauge location. There are three rain gauge stations on the area that they are in a high vulnerability level, whereas the other vulnerability level area has one rain gauge station. Each level of vulnerability area is able to represent the source of contaminant that it maybe influence the water quality of Gajahwong river.