| Title: | Management options to reduce phosphorus leaching from vegetated buffer strips |
| Authors: | Hille, S., D. Graeber, B. Kronvang, G.H. Rubaek, G.H., N. Onnen, E. Molino-Navarro, A. Baattrup-Pedersen, G.J. Heckrath and M.I. Stutter |
| Year: | 2019 |
| Journal: | Journal of Environmental Quality |
| Volume (Issue): | 48(2) |
| Pages: | 322-329 |
| Article ID: | |
| DOI: | 10.2134/jeq2018.01.0042 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | evapotranspiration assessment |
| Secondary Application Category: | none |
| Watershed Description: | Two research sites located in the southwest part of Jutland in southwest Denmark. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | SWAT was used in just a minor role to provide evapotranspiration estimates for the study. |
| Abstract: | Vegetated buffer strips (VBS) between agricultural areas
and surface waters are important retention areas for eroded
particulate P through which they may obtain critically high
degrees of P saturation imposing high risk of soluble P leaching.
We tested topsoil removal and three harvesting frequencies
(once, twice, or four times per year) of natural buffer vegetation to
reduce P leaching with the aim to offset erosional P accumulation
and high degrees of P saturation. We used a simple numerical
time-step model to estimate changes in VBS soil P levels with
and without harvest. Harvesting offset erosional deposition as it
resulted in an annual ammonium oxalate-extractable P reduction
of 0.3 to 2.8% (25-cm topsoil content) in soils of the VBS and
thus, with time, reduced potential P leaching below a baseline
of 50 mg L−1. Topsoil removal only marginally reduced potential
leaching at two sites and not anywhere near this baseline. The
harvest frequency only marginally affected the annual P removal,
making single annual harvests the most economical. We estimate
50 to 300 yr to reach the P leaching baseline, due to substantial
amounts of P accumulated in the soils. Even in high-erosion-risk
situations in our study, harvesting reduced soil P content and the
P leaching risk. We suggest harvesting as a practical and efficient
management to combat P leaching from agricultural VBS, not just
for short-term reductions of dissolved P, but also for reductions
of the total soil P pool and for possible multiple benefits for VBS. |
| Language: | English |
| Keywords: | |