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"Tesis ini membahas pola spasial Hydrologic Response Unit (HRU) pada 1997-2008 dan dampaknya terhadap aliran Daerah Aliran (DA) Ci Rasea. Pada penelitian ini digunakan model SWAT (Soil and Water Assesment Tool) berdasarkan perubahan penutup lahan untuk mendapatkan HRU dan debit aliran secara spasial dan temporal. Hasil penelitian menunjukkan bahwa pola spasial HRU dipengaruhi oleh penutup lahan secara temporal yang berdasarkan pada perubahan jumlah dan luas HRU. Dalam periode 1997-2008, akumulasi aliran permukaan dan perubahan debit aliran secara temporal dipengaruhi oleh perubahan HRU. Akumulasi aliran permukaan terbesar di DA Ci Rasea dipengaruhi oleh HRU tegalan yang ada pada daerah berjenis tanah liat dengan lereng agak miring. Sedangkan akumulasi aliran permukaan terkecil di DA Ci rasea dipengaruhi oleh HRU sawah yang ada pada daerah yang berjenis tanah lempung berpasir dengan lereng landai. Perubahan HRU tegalan menjadi HRU kebun campur pada daerah yang berjenis tanah liat dengan lereng agak miring dan HRU tegalan menjadi sawah pada daerah yang berjenis tanah lempung berpasir dengan lereng landai dapat mengurangi akumulasi aliran permukaan di DA Ci Rasea.

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This thesis discussed the spatial pattern of Hydrologic Response Unit (HRU) in 1997-2008 and its impact on flow Ci Rasea watershed. In this study, SWAT (Soil and Water Assessment Tool) model, based on land cover changed, was used to get HRU and flow in spatially and temporally. The results shown spatial pattern of HRU temporally was affected by land cover which based on change of number and area of HRU. In period 1997-2008, accumulated surface runoff and the changing of flow were affected by changes of HRU in temporally.

The biggest accumulated surface runoff in DA Ci Rasea influenced by HRU of agriculture cropland which there on area of clay soil type with slope slightly oblique. While the smallest accumulated surface runoff in DA Ci Rasea influenced by HRU of paddy field which there on area of sandy loam soil type with a gentle slope. The changed of agriculture cropland HRU to be mixed cropland HRU on area which have clay soil type with slope at a slight angle and agriculture cropland HRU to be paddy field HRU on area which have sandy loam soil type with a gentle slope can decrease accumulated surface runoff in DA Ci Rasea."

"Tujuan penelitian ini berupaya untuk mengidentifikasi perkembangan meander di Daerah Aliran Kali Pemali dalam periode tahun 2004 ?2014 dan menetapkan faktor-faktor yang mempengaruhinya. Citra Quickbird multitemporal digunakan untuk mengidentifikasi perubahan alur meander. Dinamika meander menunjukkan kecenderungan yang semakin berkelok atau sinuosity index meningkat dengan pengaruh besar dari peningkatan debit, sedangkan faktor lainnya adalah kemiringan lereng. Faktor yang sedikit mempengaruhi dinamika meander adalah penggunaan tanah tepi meander dan aktivitas manusia seperti penambangan, penlurusan (penyodetan) alur sungai, dan pembangunan tanggul buatan (artificial levee). Data yang digunakan adalah debit sungai, produksi sedimen suspensi, penggunaan tanah tepi meander, pembangunan tanggul buatan, serta lokasi tambang batu dan pasir besi.

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The present study was carried out to indentify factors influencing the meanders dynamic in Kali Pemali Watershed in the period 2004 ?2014. This study has used multitemporal Quickbird imagery to identify meanders planform change. The analysis shows that the Meanders dynamics increasingly meandering, or sinuosity index increased because increased of discharge. Factors that slightly affect the meanders dynamics are gradient, landuse, and human activities such as mining, river straightening, and construction of artificial levee. Data used in this study are river discharge, production of sediment suspension, landuse, artificial levee, and the location of mining."

"Respon hidrologi di Daerah Aliran Sungai DAS perkotaan yang telah mengalami perkembangan wilayah ditandai oleh fluktuasi debit. Indikasinya adalah tingkat flashiness yang semakin besar. Melalui pengolahan data debit harian selama tahun 1994-2016 dengan metode Indeks Richard-Baker IRB, dianalisis tingkat flashiness pada empat sungai di DAS Citarum yang dikaitkan dengan perubahan karakteristik DAS dan curah hujan. Hasil analisis keruangan dan temporal menunjukkan bahwa indeks flashiness Sungai Cimeta paling tinggi. Variasi indeks flashiness pada empat sungai tersebut relatif homogen yang menunjukkan daerah pegunungan. Indeks flashiness tertinggi terjadi pada musim pancaroba dan flashiness terendah terjadi pada musim kemarau. Kerapatan jaringan sungai dan tutupan lahan berpengaruh pada indeks flashiness. Tingkat flashiness pada tahun-tahun El Nino relatif lebih kecil dibandingkan pada tahun-tahun bukan El Nino.

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Hidrologic response in developed urban watershed marked from discharge fluctuation. The indication is increasing from flashiness level. Through daily discharge data processing during 1994 2016 with Richard Baker Index RBI , analyzed the flashiness level derived from four rivers in Citarum watershed connected with change of watershed characteristics and rainfall. The results of spatial and temporal analysis show that flashiness level of The Cimeta River is highest. Variation of flashiness index on four rivers is relatively homogeneous indicating mountainous area. The highest level of flashiness occurs during the transition season and the lowest flashiness occurs during the dry season. The density of river network and land cover affects the flashiness index. The level of flashiness in El Nino years is relatively smaller than in years not El Nino."

"ABSTRAKTelah dilakukan penelitian tentang penilaian Kualitas Air Situ Salam diKampus Universitas Indonesia, Depok. Penelitian ini bertujuan untuk mengetakualitas perairan di situ salam berdasarkan pada Nation Sanitation Foundation Water Quality Index (NSF-WQI). Penelitian ini menggunakan metode deskrip yaitu tidak dimaksudkan untuk menguji hipotesis tertentu, tetapi hanya menggambarkan obyek yang diteliti dengan data suatu variabel, gejala atau keadaan. Hasil yang diperoleh adalah kualitas air situ Salam berdasarkan Wate Quality Index (WQI) menunjukkan hasil normal (medium). Hasil normal mengindikasikan bahwa air situ Salam masih dalam kisaran tidak membahayak tingkat pencemarannya, sehingga air situ Salam masih dapat dipergunakan unt berbagai aktivitas. Hal ini berarti bahwa parameter standar penilaian kualitas masih di bawah standar baku mutu air.

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Abstract Research on water quality assessment of water quality in Situ SalamUniversitas Indonesia, Depok. This study aims to determine the quality of wat in situ Salam based on the Nation Sanitation Foundation Water Quality Index (NSF-WQI). This research uses descriptive method that is not intended to test specific hypothesis, but only describes the object under study with the data ofa variable, symptom or condition. The results obtained are based on water quality of situ Salam in Water Quality Index (WQI) were normal (medium). Normal was indicate that the water is still within the range, where situ Salam i not dangerous levels of pollution, thus there can still be used for various activities. This means that the parameters of water quality assessment standard are still below the quality standard"

"The stream character as such and its discharge behaviour are the gross results of a range of events and functions of nature. The word 'stream flow' as used in the present text, is referred to 'catchment yield'. This yield is obviously discharge, q, which has dimensions of volume, L3, and time, T, expressed here onwards in cumec (one cubic metre per second) which will ultimately be converted into a single voluminous unit litre and hence referred to as Q. As the Gola River is a spring fed river, its discharge behavior is absolutely dependent on the subsurface flow of Siwalik Ranges. It has been noticed that the subsurface flow fluctuates according to the monsoonal and non-monsoonal precipitation intensity. Hence, an interesting seasonal rhythm is noticed in the monsoonal and nonmonsoonal discharge with the changing values of stream magnitude and velocity."

"Skripsi ini membahas tentang Metode Controlled Source Audio Frequency Magnetotelluric (CSAMT) untuk mendeteksi keberadaan alterasi dan mineralisasi pada sistem urat. Dengan memanfaatkan sumber buatan guna mendapatkan sinyal yang stabil dengan cara menginjeksikan arus dari transmitter dan diterima oleh receiver. Frekuensi yang digunakan telah diatur yaitu frekuensi 5120 Hz - 64 Hz dengan target kedalaman hingga 1 km. Hasil pengukuran berupa medan magnet dan medan listrik yang ditangkap oleh receiver kemudian dengan persamaan Cagniard diperoleh nilai resistivitas semu. Pengukuran dilakukan di daerah “X” dengan sistem epitermal. Dari data lapangan dilakukan proses editing dan smoothing menggunakan software CMTpro kemudian dilakukan inversi menggunakan Bostik Inversion pada software MTSoft2D. Penggunaan metode CSAMT ini didukung dengan metode geofisika lain seperti magnetik. Metode CSAMT dapat memberikan gambaran bawah permukaan dengan penetrasi yang lebih dalam zona penyebaran emas serta didukung magnetik untuk mendapatkan korelasi pada kedalaman yang lebih dangkal. Hasil pengolahan ditampilkan secara 2D dengan software surfer 9 dan Zond Mag 2D serta 3D dengan software Geoslicer-X. Hasil penelitian menunjukkan bahwa pada ke-empat lintasan yang digunakan ditemukan adanya 2 zona anomali dengan tahanan jenis>250 ohm..meterdan di dukung oleh profil magnet smooth yang teralterasisebagai data tambahan menjadi pendukung analisa resistivity untuk menguatkan adanya mineralisasi dan alterasi. Zona pertama dan kedua di interpretasikan sebagai mineralisasi berupa vein kuarsa.

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This study discusses the Controlled Source Audio Frequency Magnetotelluric (CSAMT) method to to detect the presence of alteration and mineralization in the vein systems by utilizing artificial sources in order to obtain a stable signal by injecting current from the transmitter and accepted by the receiver. Frequency used set at 5120 Hz - 64 Hz with a target depth of up to 1 km.

Measurement results in the form of magnetic fields and electric fields are captured by the receiver, then using the equation of Cagniard, apparent resistivity values ​​obtained. Measurements was carried out in the area "X", which was an epithermal systems. Raw data were edited and smoothed by CMTpro software, and then do the inverted using the Bostick inversion on MTSoft2D.

The utilization of CSAMT method was supported by other geophysical methods such as magnetic Method. CSAMT method could provide subsurface picture with deeper penetration of gold’s distribution zones and supported by magnetic method to obtain the correlations at shallow depth.

Processing results were displayed in 2D using Surfer 9 and Zond Mag 2D software, while the 3D version using Geoslicer-X software. The results showed that along the four profiles measured was found 2 anomalie with resistivity >250 ohmmeter and also supported by altered smooth magnetic profiles as the additional data to consolidates the resistivity analysis of the existence of mineralization and alteration. The first and the second zone were interpreted as mineralisation of quartz vein."

"Besarnya erosi yang terjadi pada daerah aliran sungai bagian hulu akan menyebabkan infiltrasi terbatas, terjadi degradasi lahan serta pendangkalan sungai pada badan dan muara sungai. Salah satu DAS yang telah mengalami degradasi akibat perubahan penggunaan lahan adalah DA Ci Liwung Hulu. Tingginya degradasi yang terjadi di DA Ci Liwung Hulu diindikasikan oleh semakin tingginya tingkat erosi pada wilayah tersebut terutama pada wilayah budidaya pertanian. Dalam hal ini budidaya pertanian yang dimaksud adalah lahan pertanian yang sudah diterapkan teknik konservasi. Penelitian ini dilakukakn untuk mengetahui besaran laju erosi dengan mengkaji Hidrologic Response Unit (HRU) pada lahan budidaya pertanian yang terdapat di DA Ci Liwung Hulu dengan menggunakan Soil and Water Assessment Tool (SWAT). Teknik konservasi yang diterapkan di DA Ci Liwung Hulu antara lain terassering, agroforestry dan teras gulud. Didapatkan kesimpulan bahwa teknik konservasi agroforestry menunjukkan nilai erosi paling baik (paling rendah) dibandingkan teknik konservasi lainnya dengan kontribusi erosi sebesar 25,22 ton/ha/tahun. Hasil kalibrasi antara debit model dengan debit observasi yaitu R² = 0,9014 dan NS = 0,79 menunjukan bahwa model ini dapat diterima dan layak diaplikasikan pada DA Ci Liwung Hulu.

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The level of erosion that occurs in the upsteam watersheed will lead to limited infiltrattion, land degradation and river trivialisation and estuaries in the body. One of the watesheed that has been degraded caused by using land is the DA Ci Liwung Upstream. The high degradation that occurs in the DA Ci Liwung upstream is indicated by the hugher rate of erosion on the region, especially in the area of agriculture. In this case, agriculture cultivation intent to the agricultural land that has been applied conservation techniques. This study is applied to determine the quantity of erosion by reviewing Hidrologic Response Unit (HRU) in agricuktural cultivation land which is contained in DA Ci Liwung upstream by using the Soil and Water Assessmen Tool (SWAT). Conservation techniques applied are terracing, agroforestry and gulud terrace. It was concluded that agroforestry conservation techniques show the best value of erosion (lowest) compared with other conservation techniques with the contribution of erosion of 25.22 tonnes / ha / year. The results of the calibration between the discharge flow models with the observation that R² = 0.9014 and NS = 0.79 indicates that this model is acceptable and feasible applied to the Ci Liwung Hulu watershed."

"This study is intended to simulate the river discharges in major watersheds of northwestern Java, Indonesia. The five largest watersheds are considered: Ciujung, Cisadane, Ciliwung,Citarum, and Cimanuk. The simulation period covers the 20thcentury and early 21st century,from January 1901 to June 2006, at a monthly time step. Discharge simulation was carried out using STREAM (Spatial Tools for River Basins and Environmental and Analysis ofManagement Option). The input data for the simulation are climate (precipitation and temperature), land cover and topographic data. Setup and analysis of input data are also part ofthis study. The Mann-Kendall test and linear regression were used to detect trends. Temperature datasets show statistically significant increasing trends for all periods and areas. Significantincreasing trends of precipitation occurred in the latest 16-year period (1990-2006) in hilly and middle areas. A positive trend of simulated discharge is seen in all watersheds and periods.They are only significant for Ciujung (periods of 1950-2006 and 1975-2006), Cisadane (periods of 1950-2006 and 1990-2006), and Ciliwung (periods of 1950-2006, 1975-2006, and 1990-2006). The most noteworthy trend is seen in the 1990-2006 period. Over the course of the 20th and early decade of the 21st century, monthly discharges have increased by 3% to 9%."