Exploring impacts of vegetated buffer strips on nitrogen cycling using
a spatially explicit hydro-biogeochemical modeling approach
S. Klatt
a
, D. Kraus
a
, P. Kraft
b
, L. Breuer
b
, M. Wlotzka
d
, V. Heuveline
d
, E. Haas
a, *
,
R. Kiese
a
, K. Butterbach-Bahl
a, c
a
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research (IMK-IFU), Kreuzeckbahnstr.19, 82467 Garmisch-Partenkirchen,
Germany
b
Justus-Liebig-University of Giessen, Institute of Landscape Ecology and Resources Management (ILR), Heinrich-Buff-Ring 26, 35392 Giessen, Germany
c
International Livestock Research Institute (ILRI), 30709 Naivasha Rd, Nairobi, Kenya
d
Heidelberg University, Interdisciplinary Center for Scientific Computing (IWR), Speyerer Str. 6, 69115 Heidelberg, Germany
article info
Article history:
Received 11 February 2016
Received in revised form
29 November 2016
Accepted 3 December 2016
Keywords:
Buffer strip
Nitrate retention
Riparian zone
CMF
LandscapeDNDC
Model coupling
abstract
Agriculture has been recognized as a major anthropogenic source of surplus loads of nitrogen in the
environment. Losses of nitrate via subsurface pathways are severely threatening groundwater and sur-
face waters. This study explored the capability of a coupled hydro-biogeochemical spatially explicit
model, simulating nitrogen cycling in agricultural soils and the associated fate of excess nitrate subjected
to vertical and lateral displacement towards water bodies. Different vegetated buffer strips (VBS) were
tested for their nitrate retention capability and impacts on N
2
O and N
2
emissions. The effectiveness of a
VBS to remove nitrate by denitrification strongly depends on soil characteristics and hydrological flow
paths. Simulated N
2
emissions from VBS with high soil moisture were up to twenty-fold compared to
VBS where groundwater levels were low. Simulated streamwater nitrate concentrations without VBS
were 3.7 mg NO
À
3
l
À1
and showed a decrease to 0.1 mg NO
À
3
l
À1
for a 20 m VBS.
© 2016 Published by Elsevier Ltd.
Software and availability
Name of software CMF.
Developers ILR; contact: Philipp Kraft.
E-mail philipp.kraft@umwelt.uni-giessen.de.
Address ILR, Heinrich-Buff-Ring 26, 35392 Giessen,
Germany.
Availability Open source (GNU GPLv3 license) via website
http://fb09-pasig.umwelt.uni-giessen.de/cmf.
Program language C/Cþþ.
Program size 4 MB.
Name of software LandscapeDNDC.
Developers IMK-IFU, KIT; contact Ralf Kiese.
E-mail ralf.kiese@kit.edu.
Address IMK-IFU, KIT, Kreuzeckbahnstrasse 19, 82467
Garmisch-Partenkirchen, Germany.
Availability Freeware, upon request via website http://ldndc.
imk-ifu.kit.edu.
Program language C/Cþþ.
Program size 20 MB.
1. Introduction
Nitrate (NO
À
3
) is a serious threat to surface waters and ground-
water causing eutrophication. As such, it severely puts the quality
of drinking water at risk (Lavelle et al., 2005; Kiese et al., 2011).
According to Erisman et al. (2013) high nitrate loads were observed
during 2000 and 2003 at roughly half of European groundwater
and surface water monitoring stations. For example, in French
Brittany approximately 80% of surface waters are estimated to
exceed nitrate levels of 50 mg l
À1
set as the maximum value for
drinking water by the European Commission (Mol enat and
Gascuel-Odoux, 2002).
Efforts to establish good water quality throughout the European
* Corresponding author.
E-mail addresses: steffen.klatt@kit.edu (S. Klatt), david.kraus@kit.edu (D. Kraus),
philipp.kraft@umwelt.uni-giessen.de (P. Kraft), lutz.breuer@umwelt.uni-giessen.de
(L. Breuer), martin.wlotzka@uni-heidelberg.de (M. Wlotzka), vincent.heuveline@
uni-heidelberg.de (V. Heuveline), edwin.haas@kit.edu (E. Haas), ralf.kiese@kit.edu
(R. Kiese), klaus.butterbach-bahl@kit.edu (K. Butterbach-Bahl).
Contents lists available at ScienceDirect
Environmental Modelling & Software
journal homepage: www.elsevier.com/locate/envsoft
http://dx.doi.org/10.1016/j.envsoft.2016.12.002
1364-8152/© 2016 Published by Elsevier Ltd.
Environmental Modelling & Software 90 (2017) 55e67