Journal
AGRICULTURE ECOSYSTEMS & ENVIRONMENT
Volume 140, Issue 3-4, Pages 514-520Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.agee.2011.02.005
Keywords
DEA; Available C; Bioreactor; Long-term study; Groundwater
Funding
- Fulbright New Zealand and Landcare Research Ltd. [C09X0705]
Ask authors/readers for more resources
Denitrification walls are a low-cost approach for removing excess nitrate (NO3-) from shallow ground-water. Denitrification walls need to be maintenance-free for a number of years to remain cost effective, but little is known about the longevity of these walls. In this study, a denitrification wall constructed on a New Zealand dairy farm in 1996 was monitored to determine NO3- removal by the wall 14 years after installation. After 14 years, the denitrification wall removed 92% of NO3- input, which ranged from 2.2 to 3.7 mg N L-1. The NO3- input to the wall had decreased since first constructed, which was attributed to a change in upslope irrigation practices on the farm. Denitrifying enzyme activity (DEA) remained high after 14 years and the wall remained NO3- limited. However, total C and microbial biomass Cm the wall had decreased by approximately half, while available C remained relatively constant since year 2. By applying a first order decay curve, it was determined that total C in the denitrification wall would not be depleted for 66 years, but it is unclear at what amount of total C that denitrification would become limited. This long-term study suggested that denitrification walls are cost effective solutions for remediating groundwater NO3- pollution, as they can be effective for a number of years without any maintenance. (C) 2011 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available