International Journal of Computer Applications (0975 – 8887) Volume 149 – No.9, September 2016 20 A Fuzzy Logic based Agricultural Decision Support System for Assessment of Crop Yield Potential using Shallow Ground Water Table Mohammad Rafiuzzaman M.Sc. Graduate Faculty of Computer and Information Engineering Sakarya University, Esentepe Campus, Turkey Ibrahim Çil Professor Department of Industrial Engineering Sakarya University, Esentepe Campus, Turkey ABSTRACT Agricultural research is aimed towards increasing the productivity and food quality at reduced expenditure and with increased profit. One of the main challenges of this approach is to equip farmers with adequate and affordable information and control technology; as for higher crop yields, they need advanced expert knowledge to take proper decisions during land preparation, sowing, fertilizer management, irrigation management, integrated pest management, storage etc. In an effort to provide a methodology for better assessment on the functional outcome of this research area, an online fuzzy logic based agricultural decision support system is developed and presented in this paper. The aim of this system is to assist farmers in taking proper decisions for having a better crop production with less cost, despite the adverse nature of the soil on their farming area. Our proposed system focuses on utilizing abundant surface ground water available at the end of the wet season while benefiting from timely access to shallow groundwater from the process of capillary rises so that the farmers can have a better crop yield with or even without the expensive irrigations. The experiment was carried out in the northern and southern (coastal areas) regions of Bangladesh. Fuzzy logic is used in this case to handle uncertain or ambiguous data and knowledge of the ınput data. Experimental results presented in this paper also show that despite diverse climate nature, farmers can produce a hefty amount dry season crops in the coastal areas by utilizing shallow ground water, which was thought as impossible before. Though the experiment is carried out in Bangladesh only, if successfully implemented, this finding is believed to bring a groundbreaking agricultural advancements for the coastal area farmers in all over the world. Especially in the coastal areas of India, Myanmar, Nepal, Indonesia and Vietnam as their nature of the soil is almost same as Bangladesh. General Terms This research exploits and focuses on the following areas:  Exploring new suitable areas for farming and crop productions.  Showing the benefits of shallow ground water, which has often been overlooked in providing soil water benefits in traditional irrigated farming systems.  Developing a Decision Support System which helps farmers to take agricultural decisions to have a better crop production with minimized irrigational costs, without consulting experts. Keywords Agriculture, online Decision Support System, fuzzy Logic, flexible querying, shallow groundwater, Bangladesh 1. INTRODUCTION In Bangladesh agriculture is the single largest production sector of the economy since it comprises about 18.6% of the country's GDP and employs around 45% of the total labor force [1]. For sustaining the growing human population (almost 164 million [2]) with such small amount of area (147,570 km2 [3]), the only way to increase crop productivity with varied farming situations of this country is thorough planning with an active participation of the farmers. The agricultural economy of Bangladesh is underpinned by traditional plantings of Wet-Season Rice (T.Aman) and Rabi (dry-season) crops of Irrigated Rice (Boro), Cereals, Vegetables and Fodder Crops. In the case of wheat, consumption is estimated at 2.95 million tons in 2009/10 [4], while production remains closer to 1.0 million tons, which exceeds production levels by three times. Officials say that Bangladesh needs to import more than 2 million tons annual demand of wheat [5] as shown in figure 1. For this reason, we had used Shatabdi, which is one of the fast growing variety of wheat for conducting our experiment. Traditionally, wheat has been grown in the cooler northern regions of Bangladesh relying on supplementary irrigations from deep tube wells (Figure 2.a), but at the cost of declining water table levels [6]. This crop has not been previously sown in the far southern regions of this country as it was widely accepted as being too risky due to:  Lack of irrigation resources,  Higher temperatures,  Delayed planting times and  Increased salinity levels in southern regions. But our experimental results show that high yields (>2.5 tH -1 ) are achievable in some southern regions of Bangladesh, even without any irrigation because of the presence of shallow ground water tables [7] (Figure 2.b). An assessment of irrigation potentiality of ground water using water quality index tool has been explained in [8]. But it is very limited. The scarcity of groundwater and its importance is discussed on [9]. Against it, in this research work, shallow ground water has been considered as an underutilized renewable resource for in-situ water used by Rabi crops, such as Wheat or Mungbean in southern regions of Bangladesh. This research has shifted local views with the introduction of new technology, improved agronomy, and farmer training. It has demonstrated the potentiality of achieving grain yields between 3.0 to 4.0 t ha-1 using even one supplementary irrigation in southern Bangladesh.