3rd UF Water Institute Symposium Abstract

Submitter's Name Rishi Prasad
Session Name Posters - Understanding Natural, Anthropogenic and Legacy Sources of Nutrients
Category Understanding natural, anthropogenic and legacy sources of nutrients
Poster Number 58
Author(s) Rishi Prasad,  Graduate Student (Presenting Author)
  George  Hochmuth,  Professor
  Christopher Martinez, Assistant Professor
  Nitrogen Budgeting and Cycling for an Integrated Farm: A Step towards Improved Nitrogen Management in the Suwannee River Watershed
  Increasing levels of nitrate in ground water in the Suwannee River Basin has raised concerns over past 30 years (SRWMD, 2007). Among non point sources, agricultural operations have been associated with continuous increase in-stream nitrogen load, and surface and groundwater nitrogen contamination. Best management practices are being encouraged for agricultural fertilization in this watershed. The development and optimization of N budget for farms located in this watershed can be an effective tool to refine BMPs for reducing the N load in the watershed. Suwannee Farms is a large integrated farm located 1.25 km SW of Suwannee River. The diversity of cropping systems and the incorporation of the livestock feeding operation with the anaerobic digester employed on this farm makes it an ideal operation for determining N budget for a large farm operation. The objective of this study was to quantify the N balance associated with cropping system (potato, sweet corn), livestock feeding operation and anaerobic digestion of waste generated from livestock unit. For the growing season 2010, a partial nitrogen balance for potato crop indicated a total nitrogen recovery of seventy percent within the plant with an estimated unaccounted N loss of 85 kg ha-1 where as for sweet corn the total nitrogen recovery was 68 % with an estimated unaccounted N loss of 92 kg ha-1. The two major pathways associated with unaccounted N were hypothesized to be the leaching and volatilization losses which would be measured in subsequent seasons for sandy soil and center-pivot irrigation on this farm.