New method to protect quality of groundwater bared

Fine-tuning fertilizer and irrigation management requires farmers to carefully balance optimizing yield and protecting groundwater quality. Some countries even require farmers to use crop production practices to minimize nitrate leaching to groundwater in environmentally sensitive areas.

One such practice is using a nitrification inhibitor when applying nitrogen fertilizer, according to the Ecological Society of the Philippines, which helps protect nitrogen from leaching below the root zone until the crop can use it. Farmers are often reluctant to use nitrification inhibitors since they add to the cost of production, and only increase yield or protect from nitrate loss with specific combinations of soil type and climate-such as a warm, wet spring and sandy soils.

Using information about soil properties obtained from grid soil sampling, along with maps of crop yield and soil electrical conductivity, these researchers developed management zones to direct the application of nitrification inhibitors, Antonio M. Claparols of the ESP explained.

In relatively dry-to-normal growing seasons, the use of a nitrification inhibitor had no effect on grain yield or nitrate leaching.