1. 3DAssignment Iwan Ridwansyah y G051070071 Bogor Agriculture University 2008

2. Lake Morphometrics1 is a field concerned with studying variation and change in the form (size and shape) of the Like.[1] There are g ( p ) several methods for extracting data from shapes, each with their own benefits and weaknesses. These include measurement of lengths and angles, landmark analysis and outline analysis. Diatas lakeislocatedat100o 431 100o 5026Edan1o 151 1o 7 39S. This lake is that one oftwin lake , on the north be found another lake l d b l k caled Dibawah Lake. h k Both ofthe lake diposition on GreatSumatrafault andto certain formed b t t i activities (P f d by tectonic ti iti (P. Lehmusluoto andB.Machbub, 1977)

3. Study ea StudyArea

4. BathymetricMappingMethod GIS 3DAnalyst BathymetricMap

5. BathymetricMap B Volume of Diatas Lake = 302,06 x 106 m3 Surface Area = 12,451,642 m2 A A B

6. RetentionTime Volume Re tension time ( Rt ) = Disch arg e 302x106 m3 1.25m3/sec 7.7year. MeasurementofwaterflowinoutletofLake(used Currentmeter) Thetimerequiredtorefillanemptylakewithnaturalinflow. R t ti ti i d dt d t Retentiontimeisneededtodetermineanannuallakebudgetsforwater, i ll k b d t f t nutrient,heat,oxygencontaminants,andherbicides ItsAlsoprovideanestimateontheturnovertimeforwaterinalike,or flushingtime flushingtime

7. MorphometrycharacteristicofLakeDiatas No. No Parameter Dimension Source 1 Surface Area (m2) 12451642 Rupa bumi Map 2 Perimeter (km) 19.97 idem 3 Ma im m Length Maximum (m) 6419 idem 4 Maximum Wide (m) 2878 idem 5 Maximum depth (m) 47 Field 6 Volume (m3) 302 06 x 106 302.06 Bathymetric Map 7 Depth Average (m) 24.3 Calculation 8 Relative Depth (Zr) (%) 1.18 idem 9 Short Line Development (DL) 1.59 1 59 Idem 10 RetentionTime (year) 7.7

8. GENERATINGWATERSHED SRTMdata 3DAnalyst DerivedContur HydrologyModel DigitizeonScreen WatershedBoundary WatershedBoundary W t h dB d

9. HYDROLOGYMODEL

10. CalculatingFlowAccumulation C l l i Fl A l i

11. GeneratingStreamChannel g

12. GeneratingStreamLink G i S Li k

13. GeneratingWatershed g Differencebetween digitizeonscreenand Hydrologymodel

14. ComparedDigitizeandHydrologymodel Differencebetween digitizeonscreenand g Hydrologymodel

15. Reference WETZEL, R. G. 1983. Limnology. W. B. Saunders College Publ., Philadelphia. 743 pp. P Lehmusluoto et all 1995 National Inventory of The Major Lakes and Reservoirs in Indonesia P. Lehmusluoto, all, 1995, Indonesia, Research Institute for Water Resources Development Ministry of Public Works Agency for Research and Development Bandung, Indonesia.

16. ThankYou Th kY