1. Geological analysis with open-source software: case Cikapundung River Event: Sarasehan Geologi Populer, Badan Geologi Indonesia Dasapta Erwin Irawan 16th March 2015 2. Pre-talk quiz Pls visit www.govote.at enter code 88 74 35, and answer three yes/no questions 3. Part one: Introduction 4. Slide license need attribution (BY) for non-commercial purposes only (NC) can be copied, modied (SA, share-alike) 5. A bit about me Personal data Name: Dasapta Erwin Irawan Job: Lecturer/researcher at Groundwater Engineering Program, ITB Education (Geology, ITB): 1994-1998 (undergrad), 1999-2001 (Master), 2005-2009 (PhD) 6. A bit about me Visiting program Nov-Dec 2009 Center for Environmental Remote Sensing (CeRES), Chiba University (2009) Supervisor: Prof. Josaphat T.S. Sumantyo Research: remote sensing for hydrological purposes Feb 2014-Feb 2015 Faculty of Agriculture and Environment, University of Sydney Supervisor: Dr. Willem Vervoort Research: hydrological modeling in R 7. A bit about me Research hydrogeology hydrochemistry multivariate [statistical] analysis 8. A bit about me Media social Website: - R and Linux - Writing - SlideShare Twitter: @dasaptaerwin Email: d_erwin_irawan[at]yahoo[dot]com 9. Skills in Geology 10. Essential skills for geologist 11. Software skills (not free version) oce: Microsoft Oce (Word, Excel, ppt) -> annual subscription (from USD 10 per month) citation and referencing: EndNote -> from USD 250 statistical: Minitab, SPSS, Statistica, Stata -> basic version from USD 700 (2012) spatial / GIS: ArcGIS, Mapinfo, etc -> annual subscription (basic version from USD 100 per year) Sources: Openwetware ESRI 12. Software skills (free equivalent) oce: OpenOce or LibreOce citation and referencing: Zotero, Mendeley, etc statistical: R and R Studio, Orange Data Mining, PSPP, etc GIS: QGIS, GRASSGIS, R 13. Why open source? free as breathing mostly cross-platform (Linux, Mac, Win) strong community, hence rapid development supporting reproducibility 14. What is reproducibility in science? Every step can be: re-do re-analysed and re-evaluate re-developed 15. What is reproducibility in science? Those principles are applied to: data (items and locations) software used in the analyses: each software has distinct feature and algorithm what would happen if not everyone could purchase the software? 16. End of part one 17. Part two: Cikapundung case 18. Slide license need attribution (BY) for non-commercial purposes only (NC) can be copied, modied (SA, share-alike) 19. Background 20. Background Cikapundung has important roles: is one of the major water source for Bandung Basin: WTP Dago Pakar = 40 L/sec electrical generator (since 1923): PLTA Bengkok = 3 MW PLTA Dago = 0.7 MW Drainase kota 21. Background 22. Background Vast growth of settlements + landuse change -> declining water quality (both river and groundwater). 23. Background 24. What do we know so far? There types of groundwater and river water interactions (Lubis and Puradimaja 2006) isolated stream at Maribaya area (upstream) euent stream (or gaining stream) at Maribaya to Viaduct segment (Bandung central) inuent stream (or losing stream) from Viaduct to Dayeuhkolot some facts of springs and seepages at isolated segment (Tanuwijaya 2014). 25. What do we know so far? 26. What do we know so far? Conceptual model to mimic the interactions (Darul et.al 2014ab) It conrms the Lubis Model 27. What do we know so far? 28. What do we know so far? 29. Our question Does water quality reect the interactions? 30. Our tools R Lets do some [simple] analyses 31. Showing pairs analysis (bivariate analysis) 32. Data format variables or measurements in columns cases or samples in rows no merged columns or rows read also Data is the new soil 33. Why pairs analysis equivalent to correlation matrix the fastest way to see correlations between variables pls bear in mind correlation does not always mean causality 34. Our data 35. Our data 295 samples From ve years periode (1997, 1998, 2007, 2011, 2012) 36. Load # load data data