ANALISIS KEKERINGAN MENGGUNAKAN METODE PALMER DROUGHT SEVERITY INDEX (PDSI) SERTA DAMPAKNYA TERHADAP SISTEM IRIGASI SUBAK PADA DAERAH ALIRAN SUNGAI (DAS) PALUNG LOMBOK

Drought is a natural event that very influential on the availability of water reserves in soil, both needed for agricultural purposes and human needs. The Irrigation Areas (DI) conducted by study are Pandanduri-Swangi, Rutus, Terara Temusik which located Palung River Basin. This Analysis includes Rainfall, Regional Evaporation, calculation drought Palmer Severity Index (PDSI) method. Then do comparative Planting Pattern, management turn schedule. In this study, was carried out at 17 Rainfall Stations (ARR) with input data coming from 6 Climate (CR) Thiessen Polygon analysis. results index each Station then analyzed using ArcGIS Software isohyet method Inverse Distance Weighted (IDW) interepolation to obtain value area Area analyzed. it found that: i) Pandanduri-Swangi has an ​​4,593 hectares irrigation fairly long level between July October. ii) relationship existing where correlation obtained (48%, 61%, 72%, 73%). iii) Debits correlations is: For 40%, 48%, 71%, 30%.