INFILTRATION TO CONTROL FLOOD VULNERABILITY: A CASE STUDY OF RUBBER PLANTATION OF DAYAK DEAH COMMUNITY IN NEGARA SUB-WATERSHED, SOUTH KALIMANTAN PROVINCE

The objective of the research was to study the effects of land use and soil texture on infiltration to control flood vulnerability, which was carried out in the rubber plantation of Dayak Deah community in catchment area Jaing. The double ring infiltrometer was used to measure the infiltration on the land use of natural rubber and superior rubber in clay loam texture and sandy loam texture as the treatments with three repetitions for each. Soil sample was analyzed at soil laboratory. The rate, capacity and volume of infiltration was analyzed using Horton’s model, and the data of the rate and the volume of infiltration using statistical analysis with factorial design. The result of the analysis indicated that the infiltration rate (fc) of natural rubber reached the average constant higher and longer than the infiltration rate of superior rubber. The average infiltration capacity (f) of natural rubber was 72.185 mm/hour and superior rubber 60.904 mm/hour. The total volume (vt) of infiltration of natural rubber was 970.246 m3/ha/hour and superior rubber 736.031 m3/ha/hour. The total volume of infiltration in sandy loam texture was 965.315m3/ha/hour while in clay loam texture 740.962 m3/ha/hour. The soil texture type and the rubber type were significant to the capacity and the total volume of infiltration, but there was no interaction between soil texture and rubber type. The surface runoff in natural rubber was 32 % of the average precipitation at the research location, while in superior rubber 48 %.