Low external input sustainable agriculture: Winter flooding in rice fields increases bird use, fecal matter and soil health, reducing fertilizer requirements

This study investigated a low-external-input sustainable-agriculture (LEISA) rice production system in the Mississippi Alluvial Valley (MAV) that applied ecological principles to create waterbird habitat and enhance soil fertility. Two production sites were selected for this study (LEISA and conventional). Each production site applied a flooded treatment and a fallow treatment to select fields during the non-growing season (November 2017- March 2018). Bird fecal matter inputs and soil microbial bacteria/activity and nutrient content were quantified and compared between fields. Significantly more % total nitrogen, % total carbon, microbial richness and activity (P < 0.05) were found in flooded LEISA than other study fields. Bird fecal matter inputs on LEISA flooded fields contributed an estimated 6.1-48.9 kg N/ha/season, whereas 1.9-14.8 kg N/ha/season were added to conventionally flooded fields. Long-term application of the unique LEISA rice farming system can reduce the need for synthetic fertilizer application by > 13 %, while increasing soil organic carbon. This case study provides a foundation for future research into the agronomic benefits of creating bird habitat in rice fields, while documenting how conservation strategies support agronomic production and sustainability to foster conservation adoption.