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2. Agriculture: Area used for both annual and perennial crop cultivation, and the scattered rural settlements are closely associated with the large sized
cultivated field. 3. Shrubs Land: Area covered with shrubs, bushes and small trees, with little
wood mixed with some grasses. 4. Water Body: Area which remains water logged and swampy throughout the
year, the man made dam, the rivers with its main tributaries, and the lake. 5. Build up: Area with high density of settlement that including high density
township residences, and urban area. 6. Barren land: Area dominated by grass and small number of small trees.
3.3.1.2 Change Detection
To identify the differences between two or more land cover maps, post classification and matrix analysis was performed during image processing stage.
The matrix analysis is comparing the area of each class in each land cover map, and consists of with two kinds of values; the diagonal matrix contains unchanged
value while the other cell contain with a value that have been changed. Second step is generating the probability of changes between classes.
Figure 3.10. Change detection procedure Wijanarto, 2006
3.4 Hydrological Modeling
3.4.1 General Description of HEC-HMS
HEC-HMS model was designed to simulate the precipitation-runoff processes of dendrites watershed systems Fleming, 2009. It’s designed to be
applicable in a wide range of geographic areas for solving a broad range of
Image 1
Image 2 Registration and
Calibration Interpretation
‐ Land cover ‐ NDVI
Classification
Registration and Calibration
Interpretation - Land cover
- NDVI Classification
Transition Matrix
Trend Analysis Prediction
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problems. This includes large river basin water supply and flood hydrology to small urban or natural watershed runoff. Hydrographs produced by the program
can be used directly or in conjunction with other software for studies of water availability, urban drainage, flow forecasting, future urbanization impact,
reservoir spillway design, flood damage reduction, floodplain regulation, wetlands hydrology, and systems operation Fleming, 2009. HEC-HMS model is a
mathematical model and was designed originally to apply for runoff simulation and hydrological forecasting.
The main concept of HEC-HMS hydrological model is the use of NRCS Curve Number process, the model that can be used to assess the availability of
water on a watershed. The NRCS-CN model’s itself describing how the precipitation entrance to the watershed system through canopy interception, soil
infiltration, percolation, and evapotranspiration. These models also represent the watershed with a series of storage layer such canopy interception storage, surface
depression storage, upper ground storage, and groundwater storage.
Figure 3.11 Conceptual schematic of the continuous soil moisture model HEC-HMS, 2000
