DECISION SUPPORT SYSTEM FOR DETERMINING IRRIGATION OF LAND USING THE FUZZY LOGIC METHOD

Abstract

This study discusses the development of a decision support system to determine land irrigation recommendations based on soil pH and soil moisture values. The main problem is the need for a decision-making tool that can evaluate soil conditions more objectively, so irrigation is not performed only by manual estimation.

The method used is fuzzy logic through fuzzification, IF-THEN rule base formation, inference, and defuzzification using the centroid method. The study uses secondary data with pH values ranging from 4.2 to 8.1 and moisture values ranging from 40% to 90%. The system is implemented as a web-based application using PHP and MySQL, allowing users to enter datasets and view recommendations interactively.

The results show that the system can process pH and moisture values into irrigation recommendations categorized as 'Irrigate Immediately' or 'No Need to Irrigate'. A test case with pH 8.1 and 40% moisture produced a centroid value of 4.6273 and an irrigation recommendation, while pH 6.7 and 90% moisture produced a centroid value of 7.8873 and a no-irrigation recommendation. The system supports water-use efficiency and can serve as a basis for web-based smart agriculture development.