Web-based irrigation decision support system with limited inputs for farmers

The increasingly serious water crisis requires all water users to participate in the water saving action. The majority of scattered smallholder farmers are in the disadvantage position of information. It is difficult for them to obtain the guidance of scientific irrigation. In order to satisfy the demands of farmers in North China Plain (NCP), a web-based irrigation decision support system with limited inputs (WIDSSLI) is presented in this paper. WIDSSLI is based on the Brower/Server mode and includes user interfaces (UIs) for farmers and administrators, models, database and a weather data update system (WDUS). FAO-56 dual crop coefficient approach is adopted to simulate the soil water balance of different layers. Without in-field soil moisture monitors, the model is started from the earliest day of these days while crops are sowed or the cropland is irrigated, and soil water depletions of all layers are initialized with 0 at the beginning. Using online weather forecast, future irrigation decision is obtained by the comparison between the field water availability simulated by the system and the lower limit of the soil moisture for irrigation. By which, farmers can obtain the irrigation decision support: when irrigation is needed and how much water is required. Verification results shows that the system initialization method is reasonable, and WIDSSLI can accurately simulate the dynamics of soil water content. WIDSSLI is deployed in the internet, and its mobile version is also developed for ease of use.