Abstract

Nutrient leaching from clay soils can show extreme temporal and spatial variation. Using an optical sensor (hourly data storage), a Swedish field with vermiculite clay was monitored for water flow (Qexpressed in mm), turbidity values (TURB), and nitrate-nitrogen concentrations (CNO3N, mg L-1) in four hydrological years representing different cropping/soil management regimes. Mean TURB-Q slope (1300) decreased in the order: ploughed soil > winter wheat > unfertilized fallow > winter wheat after drainage system renovation + structure-liming of topsoil and backfill, estimated in the initial phase from 16 selected autumn events. A similar ranking was found for variability in turbidity relative to that in discharge (CVT/CVQ) in the entire autumn. Mean CNO3N-Q slope (=2) was significantly lower under fallow than in the three cropping systems (7-32), confirming results from adjacent experimental plots. A spring-period had no snow cover or intensive rain, butin situmonitoring revealed that nutrient leaching was still substantial. Particulate- and dissolved reactive phosphorus, and nitrate-nitrogen leaching was estimated reasonably well (less than 8% difference) based onin situhigh-frequency resolution measurements, compared with laboratory analysis of weekly composite samples. Accurate assessment ofC-Qrelationships in agricultural drainage water across temporal and spatial scales is therefore important.

Keywords

C-Qslope; DRP; drainage system; hysteresis; NO3N; turbidity

Published in

Acta Agriculturae Scandinavica, Section B - Soil and Plant Science
2020, Volume: 70, number: 5, pages: 392-403

SLU Authors

• Ulen, Barbro

  • Department of Soil and Environment, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Ensure availability and sustainable management of water and sanitation for all


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1080/09064710.2020.1750686

Permanent link to this page (URI)

https://res.slu.se/id/publ/105173