Soil Type Precipitation Intensity

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5.5.1 Soil Type

Soil type is related to soil erosion. For each type, scoring is given based on the level of soil sensitivity of erosion, soil type and their scoring were as Table 5 3 : Table 5-3 Soil Type and Scoring Mentan, 1982 Class Soil Type Scoring I Alluvial, Glei, Planosol, Hidromerf 15 II Latosol 30 III Brown Forest Soil, Non Calcic Brown Mediteran 45 IV Andosol, Laterit, Grumosol, Podsol, Podsolic 60 V Regosol, Litosol, Organosol, Renzina 75 Soil type at the Buper Watershed are Rendoll Renzina and Inceptisol Alluvial, for Rendoll scoring is 75 and for Inceptisol scoring is 15. These value will be used as data base of ArcView 3.3 for landuse suitability analysis.

5.5.2 Precipitation Intensity

For an annual precipitation of Buper Watershed is taken by interpolating two closest precipitation stations, namely Dock II station and Sentani station. Table 5-4 Interpolation Monthly Precipitation Sentani - Dok II Station Year Monthly Precipitation mm Total Jan Feb Mar Apr May Jun Jul Agt Sep Oct Nov Dec 2003 167 209 174 71 110 138 172 189 187 120 120 213 1,869 2004 181 151 108 176 129 134 83 59 70 139 217 71 1,518 2005 115 156 365 219 93 63 81 146 160 87 50 228 1,764 2006 262 158 438 313 122 191 191 179 300 129 136 69 2,488 2007 218 334 317 169 218 31 158 172 61 68 161 192 2,100 2008 315 242 101 206 134 232 53 53 128 136 92 162 1,853 2009 123 281 260 112 107 166 148 166 161 157 135 211 2,026 average 188 202 280 190 134 111 137 149 156 109 137 155 2,241 For the annual precipitation, scoring is given between 10 s d 50. Score 10 to precipitation 750-1250 mm year, score 20 to precipitation 1250-1750 mm year, score 30 to precipitation 1750-2250 mm year, score 40 to precipitation 2250-3250 mm year, and the score 50 to precipitation 3250 mm year. Average Annual Precipitation of Buper Watershed is 2241 mm year, so the scoring for Buper Watershed is 30. 5.5.3 Slope Buper Watershed Slope is very diverse, so the assessment should use ArcView 3.3 for providing accurate information after divided into slope range and its scoring. This scoring is required for land suitability analysis . 65 Table 5-5 Slope, Area and Scoring at Buper Watershed Slope Area km 2 Scoring 0-8 3.72 20 15-25 3.52 60 25-40 0.48 80 8-15 4.87 40 40 0.00 100

5.5.4 Landuse Suitability