17
V. CONCLUSIONS AND SUGGESTION
5. 1 Conclusions The calibration procedures consist of
two steps parameters optimization. Firstly, optimize the parameters c and WHC
according to the criterion RE. Secondly, optimize the parameter WHC again
according to the criterion R
2
, with the value of c obtained in the first step.
The results of monthly spatial runoff presented in the article had proved to be
quite efficient of describing the monthly runoff with R
2
value of 66.15 and relative error RE of 1.4 . The method can easily
be incorporated in water resources planning program to estimate monthly runoff in the
Cicatih watershed because of their simplicity and efficiency of performance. The
implication of the study is to describe the comparison between monthly spatial runoff
of the 1999 land uses pattern and the recent year land uses pattern.
The result of spatially distributed runoff clearly indicated the influence of rainfall,
land cover types, and water holding capacity WHC. However, the monthly distibuted
runoff was only affected by the rainfall. The runoff distributions of subwaterheds showed
that runoff varied from 263 mm in Ciheulang subwatershed to 26 mm in
Cikembar subwatershed. The monthly runoff distribution of Cicatih watershed showed
that the lowest runoff was 35 mm occurred in September and the highest runoff was 260
mm occurred in January. The spatial runoff distribution in Cicatih watershed reflected
that during the high rainfall period in Cicatih, maximum runoff could be found in
the forest areas 286 mm and followed by cropland areas 269 mm. And minimum
runoff was 251 mm occurred in settlement areas. In the low rainfall period, maximum
runoff 109 mm was found in forest areas. Minimum runoff was 0 mm occured in the
settlement areas, followed by cropland areas 5 mm around the mountain Salak and
mountain Pangrango. It was found that runoff increased with significant incresing
rainfall, following a positive linear function.
5. 2 Suggestion
For future applications, it is suggested to consider the rainfall-runoff pattern in
water resources planning program Cicatih Watershed, Sukabumi, West Java.
VI. REFERENCES
Abulohom MS, Shah SMS, Ghumman AR. 2001. Development of a Rainfall-
Runoff Model, its Calibration and Validation. Water Resour Manage:
15: 149-163.
Arnell NW. 1999. A simple water balance model for the simulation of
streamflow over a large geographic domain. J. Hydrol. 217: 314-335.
Asdak C, Jarvis PG, Gardingen P van, Fraser A. 1998. Rainfall interception
loss in unlogged and logged forest areas of Central Kalimantan,
Indonesia. J. Hydrol. 206: 237-244.
Adhikari. 2003. A GIS-Remote sensing compatible rainfall-surface runoff
model for regional level planning. Consulting Engineering Services
India Private Limited, DD-6, Salt Lake, Kolkata-64, West Bengal,
India.
Burt TP and Shahgedanova M. 1998. An historical record of evaporation losses
since 1815 calculated using long-term observations from the Radcliffe
Meteorological Station, Oxford, England. J. Hydrol. 205:101-111.
Calder IR, Wright IR, Murdiyarso D. 1986. A Study of evaporation from tropical
rain forest-West Java. J. Hydrol. 89: 13-31.
Calder IR. 2002. Forest and Hydrological Services: Reconciling public and
science perceptions. Land Use and Water Resources Research. 2: 2.1-
2.12.
Carlyle-Moses DE, Price AG. 1999. An Evaluation of Gash interception
model in northern hardwood stand. J. Hydrol. 210: 103-110.
Cornish PM and Vertessy RA. Forest age- induced changes in
evapotranspiration and water yield in a eucalypt forest. J. Hydrol. 242: 43-
63.
Dijk AIJM van, Bruijenzeel LA. 2001. Modelling rainfall interception by
vegetation of variable density using an adopted analytical model. Part 2.
Model validation for a tropical uoland mixed cropping system. J. Hydrol.
247: 239-262.
Fahey B and Jackson R. 1997. Hydrological impact of converting native forest and
grasslands to pine plantations, South
18
Island, New Zealand. Agricultural and Forest Meteorology. 84: 69-82.
Fernandez-Illescas CP, Porporato A, Laio F, Rodriguez-Iturbe I. 2001. The
ecohydrological role of soil texture in a water-limited ecosystem. Water
Resources Research. 37: 2863-2872.
Indonesia. 1999. Composite map [geographic map]. Bogor:
Bakosurtanal. Consist of 10 sheets. Indonesia. 1970. Soil observation map
[geographic map]. Bogor: Center for Soil and Agroclimate Research.
Consist of 1 sheet. Jacson NA. 2000. Measured and modeled
rainfall interception loss from an agroforestry system in Kenya. J.
Hydro. 100: 323-336. Johansson B and Chen D. 2005. Estimation
of areal precipitation for runoff modeling using wind data: a case
study in Sweden. Climate Research. 29: 53-61.
Kaimowitz D. 2004. Forest and Water: A Policy Perspective. Center for
International Forestry Research CIFOR. Indonesia.
Khan AA, Shah SMS, Gabriel HF. 2002. The influence of conceptual flow
simulation model parameters on model solution. Water Resour
Manage. 16: 51-69.
Karvonen T, Koivusalo H, Jauhiainen M, Palko J, Weppling K. 1999. A
hydrological model for predicting runoff from different land use areas.
J. Hydrol. 217: 253-265.
Kurnianto S. 2004. Model spasial dinamik pendugaan surplus air permukaan
menggunakan metode neraca air [Skripsi]. Bogor: Fakultas
Matematika dan Ilmu Pengetahuan Alam, Institut Pertanian Bogor.
Ladekarl UL. 1998. Estimation of soil water balance in a Danish oak stand from
measurements of soil moisture using TDR. Forest Ecology and
Management. 104: 227-238.
Lewis D, Singer MJ, Dahlgren RA, Tate KW. 2000. Hydrology in California
oak woodland watershed: a 17-year study. J. Hydrol. 240: 106-117.
Li XY, Liu LY, Gao SY, Shi PJ, Zou XY, Zhang CL. 2005. Microcatchment
water harvesting for growing Tamarix ramosissima in the semiarid loess
region of China. Forest Ecology and Management. 214: 111-117.
Lull HW. 1964. Ecological and Silvicultural Aspect. In: Chow VT, editor.
Handbook of applied Hydrology. New York: McGraw Hill.
Madsen H. 2000. Automatic calibration of a conceptual rainfall-runoff model
using multiple objectives. . J. Hydrol. 235: 276-288.
Maklouf Z and Michel C. 1994. A two- parameter monthly water balance
model for French watersheds. J. Hydrol. 162: 299-318.
Mehrotra R and Singh RD. 1998. The influence of model structure on the
efficiency of rainfall-runoff models: A comparatuive study for some
catchment of central India. Water Resour Manage. 12: 325-341.
Nash JE and Sutcliffe JV. 1970. River flow forecasting through conceptual
models. J. Hydrol. 10: 282-290. Ollinger SV, Aber JD, Federe CA. 1998.
Estimating regional forest productivity and water yield using an
ecosystem model linked to a GIS. Landscape Ecology. 13: 323-334.
Pawitan H, Taufik M, Herawati S, Kurnianto S, Askari M. 2005. Biophysical
indicators of watershed functions: case study of Cicatih Basin-
Sukabumi. Hydrometeorology Laboratory, Departement of
Geophysics and Meteorology, FMIPA-IPB.
Putty MRY and Prasad R. 2000. Understanding runoff processes using
a watershed model – a case study in the Western Ghats in South India. J.
Hydrol. 228: 215-227.
Putuhena WM and Cordery I. 2000. Some hydrological effects of changing
forest cover from eucalypts to Pinus radiata. Agricultural and Forest
Meteorology. 100: 59-72.
Starsser U and Mauser W. 2001. Modelling the spatial and temporal variations of
the water balance for the Weser catchment 1965-1994. J. Hydrol. 254:
199-214.
Sun G, McNulty SG, Shepard JP, Amatya DM, Riekerk H, Comerford NB,
Skaggs W, Swift Jr. L. 2001. Effect of timber management on the
hydrology of wetland forest in the southern United States. Forest
Ecology and Management. 143: 227- 236.
19
Sun G, McNulty SG, Amatya DM, Skaggs RW, Swift Jr. LW, Shepard JP,
Riekerk H. 2002. A comparison of the watershed hydrology of coastal
forested wetlands and the mountainous uplands in the Southern
US. J. Hydrol. 263: 92-104.
Thornthwaite CW, Mather JR. 1957. Instruction and Tables for Computing
Potential Evapotranspiration and Water Balance. Publication in
Climatology. 103.
Vandewiele GL, Xu CY, Ni-Lar-Win. 1992. Methodology and comparative study
of monthly water balance models in Belgium, China and Burma. J.
Hydrol. 134: 315-347.
Vertessy RA, Watson FGR, O’Sullivan SK. 2001. Factor determining relations
between stand age and catchment water balance in mountain ash forest.
Forest Ecology and Management. 143: 13-26.
Xiong L and Guo S. 1999. A two-parameter monthly water balance model and its
application. J. Hydrol. 216: 111-123. Xu CY. 1997. Application of water balance
models to different climatic regions in china for water resources assessment.
Water Resour Manage. 11: 51-67. Xu CY. 1999. Estimation of parameter of a
conceptual water balance model for ungauged cathments. Water Resour
Manage. 13: 353-368. Xu CY and Singh VP. 1998. A review on
monthly water balance models for water resources investigation and
climatic impact assesment. Water Resour Manage. 12: 31-50.
APPENDICES
Appendix 1. Map of Soil Types in Cicatih watershed
Appendix 2. Mean of monthly temperature during 1988-1999 periods
Year Month
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
Average
Jan 25.5 24.9 24.0 25.0 25.0 25.0 25.1 25.1 24.5 25.2 26.9 25.2 25.1
feb 25.5 24.5 25.5 24.5 25.0 24.5 24.9 24.9 25.0 25.0 25.9 24.9 25.0
Mar 26.0 25.0 25.0 25.5 25.5 24.4 25.5 25.5 25.6 25.8 26.8 25.2 25.5
Apr 26.0 25.0 26.0 25.5 25.8 26.2 26.1 26.1 27.6 26.0 26.8 25.8 26.1
May 26.5 24.5 26.0 26.0 26.0 26.2 26.3 26.3 28.2 26.3 27.1 26.0 26.3
Jun 25.4 25.0 25.5 25.5 25.5 25.8 25.7 25.7 26.0 25.7 26.6 25.7 25.7
Jul 25.4 25.5 25.5 24.5 25.0 25.5 25.3 25.3 25.7 24.9 26.0 25.2 25.3
Aug 26.0 25.0 25.0 24.5 24.5 25.0 25.3 25.3 25.5 25.6 26.4 25.5 25.3
Sep 25.5 25.0 25.5 25.5 25.5 25.0 25.6 25.6 25.6 26.1 26.0 25.9 25.6
Oct 25.5 25.5 25.5 26.5 24.5 26.0 25.7 25.7 25.6 26.8 25.9 25.7 25.7
Nov 25.1 25.0 25.0 25.5 25.0 25.5 25.5 25.5 25.9 26.6 25.4 25.5 25.5
Dec 24.5 25.4 24.5 25.5 25.2 25.0 25.2 25.2 24.6 26.3 25.6 25.2 25.2
Appendix 3. Monthly rainfall of 1999 in Cicatih watershed
Rainfall Stations Month
Cicurug Sekarwangi Sinagar Cibunar Cipendeuy
Cipetir Cikembang Pakuwon Selabintana Jan 478 441
482 108 514 507 453 368 304 Feb 397 358
426 180 322 361 317 406 272
Mar 233 244 253
263 233 402 147
250 481
Apr 293 255 371
31 343 247 275 201
392 May 215 223
138 193
366 267
281 131
256 Jun 150 132
160 15 164 139 131 196 157
Jul 91 56 83 31 30 60 40 93 130
Aug 71 83
65 40
55 131 77
127 153 Sep 91 80
117 20 20 131 24 104 205 Okt 278 278
285 244 198 303 176 562 287
Nov 187 245 221
325 335 271 271
229 538
Des 187 237 232 325 296 272 223 262
449
Appendix 4. Area rainfall of Cicatih watershed estimated using Thiesen Polygon
Appendix 5. Digital Elevation Model DEM m
Appendix 6. Map of 34 disturbed soil sampling points in Cicatih watershed
Appendix 7. Map of water holding capacity WHC in Cicatih watershed
Appendix 8. Calculation of monthly spatial runoff using PC Raster binding
Input Map altitude=topomodi.map;
area=boundary.map; thiesen=thiesen.map;
lu=lu.map; initsoilwater=initsw.map;
maxSWC=whc.map; subwatershed=Subwatershed.map;
lust=nomlust.map; ldd0=ldd.map;
Timeseries Data tmpkw = pkw.tss;
precip=NewRain.tss; volrain=volrain.tss;
volrunoff=volRo.tss; Output
Tcct= Tcit; Tavetss=Tcit.tss;
Tave=Tave; raintotal=total;
raintotaltss=rainttl.tss; raintotalcct=totalcit;
raintotalareatss=rainttlarea.tss; raintotalsub=totalsub;
raintotalsubtss=rainttlsub.tss; volrainttltss=volrainttl.tss;
rainnet=net; rainnettss=rainnnet.tss;
rainnetcct=netcit; rainnetccttss=rainnetcct.tss;
rainnetsub=netsub; rainnetsubtss=rainnetsub.tss;
rainnetthis=netthies; PET=PET;
PETsub=PETsub; PETsubtss=PETsub.tss;
PETcct=PETcit; PETccttss=PETcit.tss;
PETthis=PETthies; PETthistss=PETthies.tss;
itss=i.tss; Pef=Pef;
Pefccttss=Pefcit.tss; AET=AET;
AETcct=AETcit; AETccttss=AETcit.tss;
AETsub=AETSub; AETsubtss=AETsub.tss;
AETthis=AETthies; AETthistss=AETthies.tss;
SWC=SWC; SWCtss=SWC.tss;
SWCcct=SWCcit; SWCccttss=SWCcit.tss;
SWCsubtss=SWCsub.tss; SWClcst=SWClust;
SWClcsttss=SWClust.tss; SMS=SMS;
SMScct=SMScit; SMSccttss=SMScit.tss;
SMSsub=SMSsub; SMSsubtss=SMSsub.tss;
SMSlcst=SMSlust; SMSlcsttss=SMSlust.tss;
SMD=SMD; SMDcct=SMDcit;
SMDccttss=SMDcit.tss; SMDsub=SMDsub;
SMDsubtss=SMDsub.tss; SMDlcst=SMDlust;
SMDlcsttss=SMDlust.tss; Ro=runoff;
Rocct=Rocit; Roccttss=Rocit.tss;
Rolcst=Rolust; Rolcsttss=Rolust.tss;
Rosub=Rosub; Rosubtss=Rosub.tss;
volRo=volRo; volRotss=volRo.tss;
acc=acc; accoutlettss=accoutlet.tss;
Volacc=Volacc; Tabel Data
portion=inter.tbl; areamap
cicatih.map; timer
1 12 1; initial
I=129; report koefportion=lookupscalarportion, lu;
SWC=initsoilwater; WHC=maxSWC;
dynamic Temperature
report Tpkw=timeinputscalartmpkw,area; report Tcct=Tpkw+2.745-0.0061 altitude;
report Tave=areaaverageTcct,area; report Tavetss=timeoutputthiesen,Tave;
report tratabulan=timeoutputarea,Tave; Potential EvapotranspirationPET
i = Tave5 1.516; report itss=timeoutputarea,i;
I = sum of i a = 0.49 + 0.0179I - 0.0000771I2 + 0.000000675I3;
report PET=1610TcctIa; report PETcct=areaaveragePET,area;
report PETccttss=timeoutputarea,PET; report PETsub=areaaveragePET,subwatershed;
report PETsubtss=timeoutputsubwatershed,PET; report PETthis=areaaveragePET,thiesen;
Total Rainfall report raintotal=timeinputscalarprecip, thiesen;
report raintotaltss=timeoutputthiesen,raintotal; report raintotalcct=areaaverageraintotal,area;
report raintotalccttss=timeoutputarea,raintotal; report raintotalsub=areaaverageraintotal,subwatershed;
report rainbrutsubtss=timeoutputsubwatershed,raintotal; report volrainttltss=maptotalraintotalcellarea262820000;
Nett Rainfall report rainnet= raintotal koefportion;
report rainettss=timeoutputarea,rainnet; report rainnetcct=areaaveragerainnet,area;
report rainnetccttss=timeoutputarea,rainnet; report rainnetsub=areaaveragerainnet,subwatershed;
report rainnetsubtss=timeoutputsubwatershed,rainnet;
Effective RainfallPef report Pef= maxrainnetcct - PETcct,0;
report Pefccttss=timeoutputarea,Pef; Soil Water ContentSWC
report SWC=maxifPef gt 0 then ifSWC ge WHC then WHC+Pef else SWC+Pef else
SWCexprainnetcct-PETcctWHC,0; report SWCcct=areaaverageSWC,area;
report SWCccttss=timeoutputarea,SWC; report SWCsubtss=timeoutputsubwatershed,SWC;
report SWClcst=areaaverageSWC,lust; report SWClcsttss=timeoutputlust,SWC;
Actual EvapotranspirationAET report AET=ifSWC ge WHC then PET else PETSWCWHC;
report AETcct=areaaverageAET,area; report AETccttss=timeoutputarea,AET;
report AETsub=areaaverageAET,subwatershed; report AETsubtss=timeoutputsubwatershed,AET;
Soil Moisture SurplusSMS report SMS= ifPef gt 0 then SWCcct-WHC else 0;
report SMScct=areaaverageSMS,area; report SMSccttss=timeoutputarea,SMS;
report SMSsub=areaaverageSMS,subwatershed; report SMSsubtss=timeoutputsubwatershed,SMS;
report SMSlcst=areaaverageSMS,lust; report SMSlcsttss=timeoutputlust,SMS;
Soil Moisture Defisit SMD report SMD=ifSMS gt 0 then 0 else PET-AET;
report SMDcct=areaaverageSMD,area; report SMDccttss=timeoutputarea,SMD;
report SMDsub=areaaverageSMD,subwatershed; report SMDsubtss=timeoutputsubwatershed,SMD;
report SMDlcst=areaaverageSMD,lust; report SMDlcsttss=timeoutputlust,SMD;
Runoff Ro report Ro=SWCexp0.3SWCWHC-exp-
0.3SWCWHCexp0.3SWCWHC+exp-0.3SWCWHC; report Rocct=areaaverageRo,area;
report Roccttss=timeoutputarea,Ro; report Rosub=areaaverageRo,subwatershed;
report Rosubtss=timeoutputsubwatershed,Ro; report Rolcst=areaaverageRo,lust;
report Rolcsttss=timeoutputlust,Ro; report volRotss=maptotalRocellarea262820000;
report volRo=timeinputscalarvolrunoff,area; Runoff accumulation
report acc= accufluxldd0,Ro; accoutlet=mapmaximumacc;
report accoutlettss=timeoutputarea,accoutlet;
ii
CALIBRATION OF MONTHLY SPATIAL RUNOFF FROM THE ROOT ZONE USING WATER BALANCE METHOD A Case Study in Cicatih
Watershed, Sukabumi, West Java
TEUKU ACHMAD IQBAL
DEPARTMENT OF GEOPHYSICS AND METEOROLOGY FACULTY OF MATHEMATICS AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY 2006
iii
ABSTRACT
TEUKU ACHMAD IQBAL
. Calibration of Monthly Spatial Runoff from the Root Zone Using Water Balance Method A Case Study in Cicatih Watershed, Sukabumi, West Java. Under
the direction of DANIEL MURDIYARSO.
This study calibrated the monthly spatial runoff from the root zone using simple water balance in Cicatih watershed, Sukabumi, West Java. Soil layer of 10-30 cm was taken to represent the root
zone. The method of monthly runoff by Xiong and Guo 1999 was applied. Geographic information system GIS was used to estimate spatial and monthly runoff distributions. The result
was satisfactory. The value of R
2
for Cicatih watershed was 66.15 and the relative error RE was 1.4 . It was capable of describing the monthly spatial runoff and had produced quite good
estimation. Spatially distributed runoff clearly indicated the influence of rainfall, land cover types, and water holding capacity WHC. However, monthly runoff was only affected by the rainfall.
The runoff contribution from the garden areas was the highest. The lowest contiribution of runoff was found in the grass areas. Monthly runoff from the forest areas was the highest over the year. It
was found that runoff increased as the significant increased of rainfall.
iv
CALIBRATION OF MONTHLY SPATIAL RUNOFF FROM THE ROOT ZONE USING WATER BALANCE METHOD A Case Study in Cicatih
Watershed, Sukabumi, West Java
TEUKU ACHMAD IQBAL G 24101023
Research Report To fulfill the requirement for a Bachelor Degree in Science
At the Department of Geophysics and Meteorology Faculty of Mathematics and Natural Sciences
DEPARTMENT OF GEOPHYSICS AND METEOROLOGY FACULTY OF MATHEMATICS AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY 2006
v Title : CALIBRATION OF MONTHLY SPATIAL RUNOFF FROM THE
ROOT ZONE USING WATER BALANCE METHOD A Case Study in Cicatih Watershed, Sukabumi, West Java
Name : Teuku Achmad Iqbal Nrp : G 24101023
Approved by: Supervisor
Prof. Dr. Daniel Murdiyarso
NIP. 130804892
Dean of Faculty of Mathematics and Natural Sciences Bogor Agricultural University
Dr. Ir. Yonny Koesmaryono, M.Si
NIP. 131473999 Graduation date:
vi
BIOGRAPHY
Teuku Achmad Iqbal was born in Jakarta at August 30, 1983 with parents name Teuku Syarif and Kemala Sari. He has two brothers.
After graduation from the SMA 109 Jakarta in 2001, he was enrolled IPB through the USMI process. He joined the Department of Geophysics and Meteorology, Faculty of
Mathematics and Natural Sciences in 20022003. He was a member of a student association interested in Agricultural Meteorology, HIMAGRETO. Iqbal was the assistant of
Hydrometeorology Practical Class in 20052006.
1
I. INTRODUCTION