Study of the Recharge Area on Water Basin Soil with Remote Sensing Method Using Satellite Imagery Landsat 7 ETM + and Geographic Information Systems ( GIS ) ( Case Study : Pasuruan District )

AbstracWater is natural resources that is very essential for living creatures and the environment. Along with the increase of population , will increase the water demand and reduce the area of free land / open green space for the formation of ground water. By considering soil water conservation aspects, it is necessary to conduct a study of the recharge area on water basin soil in Pasuruan. This study was to determine the condition of the recharge area in the Basin Groundwater Pasuruan in 2003 and 2014. So it will be k[1]nown the changes of the vegetations density and land cover in the recharge area that can affect infiltration process in order to conserve water resources in CAT Pasuruan. From these changes it would be able to make the prediction of future conditions in the recharge area in CAT Pasuruan. This study uses Remote Sensing using Satellite imagery Landsat and Geographic Information System (GIS). Studies to determine the recharge area is influenced by several parameters, that is slope of land, lithology and Rainfall. Processing results obtained vegetation density changes of the recharge area in 2003-2014, high vegetation density decreased by 4330,89 Ha, so that changes in the high vegetation density in 2025 is predicted to be 52305,39 Ha and become 52176,78 Ha in 2030. While land cover changes produce changes in forest land cover increased by 569,88 Ha , so that changes in forest land cover in 2025 is predicted to be 37563,88 Ha and became 38720,494 Ha in 2030. The relationship between vegetation density and land cover of the recharge area in 2003 2014 obtained high vegetation density that experienced an increase area, which is on garden land cover amounting to 1144,80 Ha, 943,02 Ha of forest, 947,79 Ha of settlements land cover and 262,53 Ha of vacant land. And that experienced an increase with low vegetation density are the fields amounting to 943,02 Ha and 277,47 Ha of vacant land. Land cover vegetations that dominates throughout the recharge area is a mahogany tree vegetation, and sengon.

AbstracWater is natural resources that is very essential for living creatures and the environment.Along with the increase of population , will increase the water demand and reduce the area of free land / open green space for the formation of ground water.By considering soil water conservation aspects, it is necessary to conduct a study of the recharge area on water basin soil in Pasuruan.This study was to determine the condition of the recharge area in the Basin Groundwater Pasuruan in 2003 and 2014.So it will be k [1]nown the changes of the vegetations density and land cover in the recharge area that can affect infiltration process in order to conserve water resources in CAT Pasuruan.From these changes it would be able to make the prediction of future conditions in the recharge area in CAT Pasuruan.This study uses Remote Sensing using Satellite imagery Landsat and Geographic Information System (GIS).Studies to determine the recharge area is influenced by several parameters, that is slope of land, lithology and

I. INTRODUCTION 1
ater is a natural resource that is essential to living creatures and the environment , including all the people of Indonesia .Along with the increase of population , will increase the water demand.Beside that, 1 Isniyatus Sholikhah and Muhammad Taufik are with Department of Geomatics Engineering Institut Teknologi Sepuluh Nopember, Surabaya, 60111, Indonesia.E-mail: isniyatus@gmail.com,taufik_srmd@yahoo.com the building construction also leads to reduced of free land / open green space for the formation of ground water.It can be seen from ground water use in CAT Pasuruan which currently leads in the region that hydrogeologically was a recharge area.By considering aspects of soil water conservation it is necessary to 2 Kukuh Sudjatmiko is with Departemen of Dinas Energi dan Sumber Daya Mineral Provinsi Jawa Timur.E-mail: kukuh.sudjatmiko@gmail.comW conduct a study of the recharge area on water basin soil in Pasuruan.[1] .
By considering aspects of soil water conservation it is necessary to conduct a study of the recharge area on water basin soil in Pasuruan.This study was to determine the condition of the recharge area in the Basin Groundwater Pasuruan in 2003 and 2014.So it will be known the changes of the vegetations density and land cover in the recharge area that can affect infiltration process in order to conserve water resources in CAT Pasuruan.From these changes it would be able to make the prediction of future conditions in the recharge area in CAT Pasuruan.Vector data used in this research geologic map of the malang and probolinggo, contour map of pasuruan district, raifall map of pasuruan district, and Basin Groundwater (CAT) map of jawa timur province.
The research location at Groundwater Basin region precisely at the administrative borders of Pasuruan (Figure 1).This study was to determine the condition of the recharge area in the Basin Groundwater Pasuruan in 2003 and 2014.So it will be known the changes of the vegetations density and land cover in the recharge area that can affect infiltration process in order to conserve water resources in CAT Pasuruan.From these changes it would be able to make the prediction of future conditions in the recharge area in CAT Pasuruan.This study uses Remote Sensing using Satellite imagery Landsat and Geographic Information System (GIS).
Data processing consists of determining the recharge area, land cover and the vegetation index.Determining recharge area is done by scoring the decisive parameters comprising the slope , lithology and rainfall .While the determination of the density of vegetation using vegetation index Normalized Difference Vegetation Index ( NDVI ) .NDVI has a function algorithm NDVI = ( Rnir -Rred ) / ( Rnir + Rred ) [2] .The detailed procedure is shown with the help of flow chart in

A. Determining Recharge Area
Determination of recharge areas in Pasuruan CAT was influenced by several parameters , that is slope , lithology, and rainfall [3].The procedure of determination recharge areas in Pasuruan is shown with the help of flow chart in Figure 3.The criteria of slope parameter is based Contour Map ( Figure 4).

b) Lithology
The criteria of lithologi parameter is based Geologic Map ( table 1).The criteria of rainfall parameter is based Geologic Map.Determination of recharge areas in Pasuruan CAT is done by scoring with metode Overlay Weighted Sum method the decisive parameters comprising the slope, lithology and rainfall.The results of determination obtained main recharge areas, and, removable area ( Figure 6).Geometric correction used to reduces radiometric errors in the image, as well as to cultivate the vegetation index algorithm that uses data from the image reflectance value.
Grading on the vegetation index NDVI algorithm refers to the Ministry of Forestry regulation of 2003 which divided the class into three classes NDVI , which is rare, medium , and high ( Table 1 ) [3] .Processing results obtained vegetation density changes of the recharge area in 2003-2014, high vegetation density decreased by 4330,89 Ha.
To predict the condition of high vegetation density change in the future, may use linear regression equation y = -4330.x+ 65298.
From the the linear regression equation, high vegetation density in 2025 is predicted to be 52305.39ha and in 2030 became 52176.78Ha.
The Results of recharge area classification based on NDVI values, presented in the map ( Figure 8 and Figure 9 ).

C. Land Cover
Land cover classification is done by the method of terselia classification, type maximum likellihood.Accuracy of processing land cover is calculated using confusion matrix and sample as many as 23 points, the tolerance limits given is ≥ 80%.Confusion matrix calculations in 2003 amounted to 90.75% and in 2014 amounted to 98.45%.The following table are land cover area calculations of recharge area in year 2003-2014 (table 3): From the data processing, forest cover increased by 569.88 Ha.To predict changes in forest cover in the future may use linear regression equation y = 569.8x +36994.
From the the linear regression equation can be determined prediction changing conditions of forest cover in 2025 is predicted to be 37563.88ha and in 2030 became 38720.494Ha.

D. Analysis of Recharge Area changes
Analysis of reharge area changes obtained from the the relationship changes between land cover and vegetation density of recharge areas in years 2003-2014.And at the low density that was increase are fields amounted to 943,02 hectares, vacant land of 277.47 hectares, and clouds.Land cover vegetation that dominates in all recharge area are mahogany and sengon trees.
High vegetation density increases in forest land, this suggests that the reforestation of forest areas capable of increasing the density of vegetation on forest land cover.
In addition, the increase also occurred on garden land, this indicates that the increased activity of production and planting vegetation in an effort to protect the soil surface from the impact of rain water, runoff decrease, hold soil particles through the root system and maintain stability in the soil's capacity to absorb water.
On the one hand there is an increase in the area with low vegetation density with land cover of settlement and vacant land, this indicates that there is a land conversion that could threaten the sustainability of water resources.

IV. CONCLUSION
Based on the results and analysis, it can be concluded: a) Based on the analysis it was concluded that the determination of the recharge area obtained zones is the recharge area and loose areas.
Rainfall.Processing results obtained vegetation density changes of the recharge area in 2003-2014, high vegetation density decreased by 4330,89 Ha, so that changes in the high vegetation density in 2025 is predicted to be 52305,39 Ha and become 52176,78 Ha in 2030.While land cover changes produce changes in forest land cover increased by 569,88 Ha , so that changes in forest land cover in 2025 is predicted to be 37563,88 Ha and became 38720,494 Ha in 2030.The relationship between vegetation density and land cover of the recharge area in 2003 -2014 obtained high vegetation density that experienced an increase area, which is on garden land cover amounting to 1144,80 Ha, 943,02 Ha of forest, 947,79 Ha of settlements land cover and 262,53 Ha of vacant land.And that experienced an increase with low vegetation density are the fields amounting to 943,02 Ha and 277,47 Ha of vacant land.Land cover vegetations that dominates throughout the recharge area is a mahogany tree vegetation, and sengon.Keywords Recharge Area, CAT Pasuruan, Remote Sensing.
II. METHOD Image data used in this research is Satellite Imagery Landsat 7 ETM + and Landsat 8 at the public domain USGS (United States Geological Survey) http://earthexplorer.usgs.gov/Path 118 and Row 65 of September 1 st , 2014 and May 22 th , 2003 acquisition of the data.

Figure 1 .
Figure 1.Map of Study Area

Figure 2 .
Figure 2. Flow chart showing detailed procedure

Figure. 3 .
Figure. 3. Flow chart showing determination of recharge areas in Pasuruan CAT procedure.

TABLE 2 .
THE RESULTS OF THE NDVI CLASSIFICATION

TABLE 3 .
THE RESULTS OF THE LAND COVER CLASSIFICATION

TABLE 4 .
Gardens of 1144.80 hectares, 943.02 hectares of forest, settlement of 947.79 hectares and 262.53 hectares of vacant land.
TotalFrom data processing, obtained the high vegetation density that increased are: b) Processing results obtained vegetation density changes of the recharge area in 2003-2014, high vegetation density decreased by 4330,89 Ha c) High vegetation density in 2025 is predicted to be 52305,39 Ha and become 52176,78 Ha in 2030.d) Processing results obtained land cover changes of the recharge area in 2003-2014, land cover forest increased by 569,88 Ha. e) To predict the future of forest change can use the linear regression equation y = 569.8x +36994.f) With the linear regression equation, changes in forest cover in 2025 is predicted to be 37563.88ha and in 2030 became 38720.494Ha. g) The relationship between vegetation density and land cover of the recharge area in 2003 -2014 obtained high vegetation density that experienced an increase area, which is on garden land cover amounting to 1144,80 Ha, 943,02 Ha of forest, 947,79 Ha of settlements land cover and 262,53 Ha of vacant land.And that experienced an increase with low vegetation density are the fields amounting to 943,02 Ha and 277,47 Ha of vacant land.h) Land cover vegetations that dominates throughout the recharge area is a mahogany tree vegetation, and sengon.