Pola dan distribusi temperatur dan TDS di tiga lokasi sungai segmen Cimahi-Bandung Utara dan perkiraan sumbernya
Authors: Aditya Sri , Irawan Dasapta Erwin 
Published: November 2018

Complete file thesis is available on Overleaf platform https://www.overleaf.com/read/wqqfskwyhjyk data while all data and R codes are available on Github https://github.com/dasaptaerwin/Pola-dan-distribusi-temperatur-dan-TDS-air-sungai-di-Bandung &lt;&lt; Bahasa Indonesia &gt;&gt; Variasi harian data kualitas air dapat dianalisis untuk mengetahui proses yang terjadi pada air sungai itu sendiri juga interaksinya dengan air tanah, khusus pada zona hyporheic. Observasi dilakukan di tiga lokasi anak Sungai Cikapundung di tahun 2017 (periode Maret-November 2017). Pengukuran dilakukan pada tiga lokasi di DAS S. Cikapundung (diurutkan dari utara-selatan): S. Ciawitali lokasi Curug Panganten (CP) dan Grand Royal Pancanaka (GRP), S. Cibeureum lokasi Pondok Hijau Indah (PHI). Tata guna lahan berevolusi dari lahan terbuka berupa hutan dan lahan perkebunan/pertanian di lokasi CP dan GRP, ke perumahan di PHI. Sungai di ketiga lokasi itu menjadi muara dari saluran-saluran air yang melewati kawasan di tepi kiri dan kanannya.Pengukuran debit (meter/detik), temperatur air sungai (derajat Celcius), temperatur udara (derajat Celcius), dan TDS (total dissolved solids) (ppm). Pengukuran dilakukan dengan alat portabel merk Lutron, masing-masing dengan ketelitian 0.01 pada masing-masing satuan yang berkaitan. Pengukuran dilakukan empat kali di masing-masing lokasi: pukul 10.00, 12.00, 14.00, dan 16.00. Data kemudian dianalisis menggunakan piranti lunak open source R untuk teknik time series.Hasil pengukuran di ketiga lokasi tersebut menunjukkan variasi mingguan dan bulanan. Untuk variasi minggu, nilai TDS naik mulai hari Jumat dan turun pada hari Senin. Lokasi yang paling konsisten menunjukkan gejala ini adalah PHI. Variasi bulanan menunjukkan peningkatan di bulan Juni dan turun di bulan Juli. Pola ini terjadi di tiga lokasi tersebut. Pada titik ini, kami berpendapat bahwa pola tersebut diduga berkaitan dengan aktivitas manusia yang meningkat di akhir minggu. Untuk pola bulanan, ada indikasi bahwa peningkatan TDS bersamaan dengan liburan Lebaran 2017. Dugaan tersebut perlu diklarifikasi lebih lanjut dengan pengukuran kandungan nutrien (nitrat, nitrit, fosfat, klorin, dan sulfat) secara time series. Dari riset ini, dapat kami sampaikan bahwa data time series sangat berperan dalam analisis lingkungan, sehingga layak untuk dikembangkan. &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; In English &gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt; Many processes can influence river water and groundwater to its current form. Daily variation of water quality data can be analyzed to understand such processes. This research mainly analyzed time series data of TDS from river water to under- stand the processes. We suspect that local drainage has a strong influence to the increasing values of TDS in the river water. We collected the data from March to November 2017 at three locations (from north to south): S. Ciawitali located at Curug Panganten (CP) and at Grand Royal Pancanaka (GRP), and S. Cibeureum located at Pondok Hijau Indah (PHI). At each locations we measured air temper- ature, river water temperature, and TDS. The measurements were conducted four times/day, 3 days/week in eight months. To support our claims, we also analyzed 310 water quality dataset that were available to classify the samples. We used open source applications, R, to produce the calculation and the plots. From the three locations, we find that TDs values on CP and PHI show a cyclic weekly pattern, with the values from PHI are averagely 20% higher than values from CP at given period. We don’t find the same pattern at GRP. The values from that location show a random pattern. Interestingly, we find an increasing trend from June to July. We argue that the cyclic pattern at CP and PHI are brought by many drainage outlets in the river bank. Such drainage collects domestic waste from housings and nearby accommodations (hotels) and tourist objects. Both locations are known as part of tourist object area at northern Bandung. GRP does not show the same situation because the TDS most likely only from the nearby GRP housing. The observation site is located at a man made channel that connect two natural channel through GRP housing complex. We argue that the TDS values at the channel capture a closed system drainage, compare to the open system at CP and PHI. Based on the multi- variable analysis, we also see a close interaction between groundwater and river water at various places in Bandung area. This phenomenon should add our under- standing on the patterns of TDS value. Such close interactions between groundwater and river water, should be the focus of the Bandung authorities. In this such close interactions, the contamination present in the river environment could come both from the river and the groundwater system. Both water have the same chance to send out man-made pollution in the environment.