SPATIAL ANALYSIS OF WATER BALANCE DISTRIBUTION FOR SIMULATION OF TIMING AND PATTERNS OF RICE AND CROP PLANTING IN THE REGION OF TYPE D RAINFALL IN THE SOUTH KONAWE REGENCY

Abstract

Water availability plays a crucial role in the environmental hydrological cycle, where the concept states that the amount of water in a specific area on the Earth’s surface is influenced by the input and output of water over a certain period. Water imbalance can lead to excess (surplus) and deficit (water shortage), impacting various sectors, including the agricultural sector, particularly in food crop cultivation, causing seasonal shifts and changes in planting patterns. These impacts can be minimized through adequate land and environmental management, achieved by calculating the water balance conditions in a given region. This research aims to (1) analyze the spatial distribution of land water balance in a type D rainfall region and (2) determine the timing and crop planting patterns based on the water balance of rice and secondary crops in the type D rainfall region. The study employs survey methods and analysis using the Thornthwaite water balance calculation. The results indicate water surplus in the Palangga and Baito subdistricts with an 8-month surplus period, reaching 192.40 mm month-1 in June and a minimum of 2.04 mm month-1, covering various sampling points and administrative areas such as Kiaea, Watudemba, Watumerembe, Wawonggura, Eewa, Onembute, Anggondara, Mekar Sari, Wawouru, Aosole, Sanggi-sanggi, Palangga, Tolihe, Sambahule, Matabubu, Mekarjaya, Wonua Raya, Ahuangguluri, Amasara, Wawouru, Mekarsari, Anggondara, Aosole, Eewa, and Onembute. Water deficit in the Palangga and Baito subdistricts occurs for four months, peaking at 58.59 mm month-1 in June at point 6 and reaching a minimum of 4.68 mm month-1 in February at point 2. The Palangga and Baito subdistricts exhibit a cropping pattern of corn + mung bean - irrigated rice - fallowing/vegetables; soybean/irrigated rice - fallowing/vegetables; corn + peanuts - irrigated rice - fallowing/grass for animal feed.