ANALYSIS OF AGRICULTURAL DROUGHT BASED ON DAILY WATER BALANCE AT RAINFED FARM LAND

Abstract

Agricultural drought related to soil moisture which is characterized by a deficit of soil moisture. The condition leads to the limitedness for crop culture due to soil moisture availability is not enough for plant’s needs. Therefore, this research aims at finding when exactly the agricultural drought occurred using water balance approach. This research employed a descriptive exploratory method which was done by surveying in the field and also supported by laboratory analysis. The component of daily local weather data, included air temperature, air relative humidity, soil temperature, soil moisture, and rainfall at two locations, each at Ampel and Teras District, Central Java, Indonesia from October 1st, 2015 to March 31^st, 2016. Then laboratory analysis to determine soil water availability at pF 2.54 – 4.2 was conducted using hydraulic properties calculator. The results show that the meteorological drought at both locations ended earlier than the agricultural drought, which was the third decades (20^th- 30^th) of October 2015.  But the agricultural drought ended on decadal (Nov. 2^nd and Nov. 5^th, 2015) At Ampel and Teras district, respectively. During dry conditions, the rain-fed lands were left fallow until the end of the agricultural drought, which enters rainy season.  Start from this point, the lands can be planted with rice.