HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Patni, N. K. Articles by Jui, P. Y. Search for Related Content PubMed Articles by Patni, N. K. Articles by Jui, P. Y. Agricola Articles by Patni, N. K. Articles by Jui, P. Y.

Groundwater Quality under Conventional and No Tillage: I. Nitrate, Electrical Conductivity, and pH

Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, ON Canada K1A 0C6.

^* Corresponding author (patnin{at}em.agr.ca).

ABSTRACT

The use of conservation tillage is increasing in North America, but information on its effect on water quality in cold climatic regions is limited. To obtain such information, the effect of no-tillage (NT) and conventional tillage (CT) treatments on nitrate-nitrogen (NO₃-N) concentration, specific electrical conductivity (EC), and pH in shallow groundwater (1.2, 1.8, 3.0, and 4.6 m depths) was studied over four successive crop years in corn fields (loam soil) of approximately 3 ha each, located in eastern Ontario. Water table elevation was also monitored during three crop years. Average NO₃-N concentration at the 1.2, 1.8, and 4.6 m depths was consistently higher under CT than under NT in every crop year and every season. However, the effect of tillage was not significant at P < 0.05. Nitrate concentration decreased significantly with depth. It was about two to three times the drinking water limit of 10 mg/L as NO₃-N at the 1.2, 1.8, and 3.0 m depths. At the 4.6 m depth, NO₃-N concentrations were mostly low but increased with time. Changes in water table elevation appeared to affect NO₃-N concentrations at the 1.2 m depth under NT only. At a given depth, EC and pH of groundwater were not affected by tillage treatment. However, within each tillage treatment, values increased significantly with depth. Results from this study indicated a large spatial variability in NO₃-N and EC values in groundwater, which could have masked small tillage effects. More intensive temporal and spatial sampling may be required to establish tillage treatment effects, if any.

N.K. Patni, current address: Pacific Agri-Food Research Centre, Agassiz, BC V0M 1A0 Canada.

Centre for Food and Animal Research Contribution no. 2427.

Received for publication April 14, 1997.

This article has been cited by other articles:

				D. B. Jaynes, T. C. Kaspar, T. B. Moorman, and T. B. Parkin In Situ Bioreactors and Deep Drain-Pipe Installation to Reduce Nitrate Losses in Artificially Drained Fields J. Environ. Qual., March 1, 2008; 37(2): 429 - 436. [Abstract] [Full Text] [PDF]

				A. A. Elmi, C. Madramootoo, M. Egeh, A. Liu, and C. Hamel Environmental and Agronomic Implications of Water Table and Nitrogen Fertilization Management J. Environ. Qual., November 1, 2002; 31(6): 1858 - 1867. [Abstract] [Full Text] [PDF]