Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils
Nitrate–nitrogen (NO<sub>3</sub>–N) as well as dissolved organic carbon (DOC) and nitrogen (DON) concentrations and losses were studied for three and two years, respectively, in a small catchment dominated by a degraded peatland used as intensive grassland. Concentrations in the shallow...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-08-01
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| Series: | Biogeosciences |
| Online Access: | http://www.biogeosciences.net/11/4123/2014/bg-11-4123-2014.pdf |
| _version_ | 1818367823032877056 |
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| author | B. Tiemeyer P. Kahle |
| author_facet | B. Tiemeyer P. Kahle |
| author_sort | B. Tiemeyer |
| collection | DOAJ |
| description | Nitrate–nitrogen (NO<sub>3</sub>–N) as well as dissolved organic carbon (DOC) and
nitrogen (DON) concentrations and losses were studied for three and
two years, respectively, in a small catchment dominated by a degraded peatland used as
intensive grassland. Concentrations in the shallow groundwater were spatially
and temporally very variable, with NO<sub>3</sub>–N being the most dynamic component
(7.3 ± 12.5 mg L<sup>−1</sup>) and ranging from 0 to 79.4 mg L<sup>−1</sup>.
Average NO<sub>3</sub>–N concentrations of 10.3 ± 5.4 mg L<sup>−1</sup> (0 to
25.5 mg L<sup>−1</sup>) in the ditch draining the catchment and annual NO<sub>3</sub>–N
losses of 19, 35 and 26 kg ha<sup>−1</sup> confirmed drained peatlands as an
important source of diffuse N pollution. The highest NO<sub>3</sub>–N losses
occurred during the wettest year. Resulting from concentration of
2.4 ± 0.8 mg L<sup>−1</sup> (0.7 to 6.2 mg L<sup>−1</sup>), DON added a further
4.5 to 6.4 kg ha<sup>−1</sup> to the N losses and thus formed a relevant
(15%) component of the total N losses. Ditch DOC concentrations of
24.9 ± 5.9 mg L<sup>−1</sup> (13.1 to 47.7 mg L<sup>−1</sup>) resulted in DOC
losses of 66 kg ha<sup>−1</sup> in the wet year of 2006/2007 and 39 kg ha<sup>−1</sup>
in the dry year of 2007/2008. Ditch DOC concentration were lower than the
groundwater DOC concentration of 50.6 ± 15.2 mg L<sup>−1</sup> (14.9 to
88.5 mg L<sup>−1</sup>). Both DOC and N concentrations were governed by
hydrological conditions, but NO<sub>3</sub>–N reacted much faster and clearer on
rising discharge rates than DOC, which tended to be higher under drier
conditions. In the third year of the study, the superposition of a very wet
summer and land use changes from grassland to arable land in a part of the
catchment suggests that, under re-wetting conditions with a high groundwater
table in summer, NO<sub>3</sub>–N would diminish quickly, while DOC would remain on
a similar level. Further intensification of the land use, on the other hand,
would increase N losses to receiving water bodies. |
| first_indexed | 2024-12-13T22:58:10Z |
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| institution | Directory Open Access Journal |
| issn | 1726-4170 1726-4189 |
| language | English |
| last_indexed | 2024-12-13T22:58:10Z |
| publishDate | 2014-08-01 |
| publisher | Copernicus Publications |
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| series | Biogeosciences |
| spelling | doaj.art-59e3cad8710045319593dc00cce9627a2022-12-21T23:28:28ZengCopernicus PublicationsBiogeosciences1726-41701726-41892014-08-0111154123413710.5194/bg-11-4123-2014Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soilsB. Tiemeyer0P. Kahle1Thünen Institute for Climate-Smart Agriculture, Bundesallee 50, 38116 Brunswick, GermanyFaculty of Agricultural and Environmental Sciences, Rostock University, Justus-von-Liebig Weg 6, 18051 Rostock, GermanyNitrate–nitrogen (NO<sub>3</sub>–N) as well as dissolved organic carbon (DOC) and nitrogen (DON) concentrations and losses were studied for three and two years, respectively, in a small catchment dominated by a degraded peatland used as intensive grassland. Concentrations in the shallow groundwater were spatially and temporally very variable, with NO<sub>3</sub>–N being the most dynamic component (7.3 ± 12.5 mg L<sup>−1</sup>) and ranging from 0 to 79.4 mg L<sup>−1</sup>. Average NO<sub>3</sub>–N concentrations of 10.3 ± 5.4 mg L<sup>−1</sup> (0 to 25.5 mg L<sup>−1</sup>) in the ditch draining the catchment and annual NO<sub>3</sub>–N losses of 19, 35 and 26 kg ha<sup>−1</sup> confirmed drained peatlands as an important source of diffuse N pollution. The highest NO<sub>3</sub>–N losses occurred during the wettest year. Resulting from concentration of 2.4 ± 0.8 mg L<sup>−1</sup> (0.7 to 6.2 mg L<sup>−1</sup>), DON added a further 4.5 to 6.4 kg ha<sup>−1</sup> to the N losses and thus formed a relevant (15%) component of the total N losses. Ditch DOC concentrations of 24.9 ± 5.9 mg L<sup>−1</sup> (13.1 to 47.7 mg L<sup>−1</sup>) resulted in DOC losses of 66 kg ha<sup>−1</sup> in the wet year of 2006/2007 and 39 kg ha<sup>−1</sup> in the dry year of 2007/2008. Ditch DOC concentration were lower than the groundwater DOC concentration of 50.6 ± 15.2 mg L<sup>−1</sup> (14.9 to 88.5 mg L<sup>−1</sup>). Both DOC and N concentrations were governed by hydrological conditions, but NO<sub>3</sub>–N reacted much faster and clearer on rising discharge rates than DOC, which tended to be higher under drier conditions. In the third year of the study, the superposition of a very wet summer and land use changes from grassland to arable land in a part of the catchment suggests that, under re-wetting conditions with a high groundwater table in summer, NO<sub>3</sub>–N would diminish quickly, while DOC would remain on a similar level. Further intensification of the land use, on the other hand, would increase N losses to receiving water bodies.http://www.biogeosciences.net/11/4123/2014/bg-11-4123-2014.pdf |
| spellingShingle | B. Tiemeyer P. Kahle Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils Biogeosciences |
| title | Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils |
| title_full | Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils |
| title_fullStr | Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils |
| title_full_unstemmed | Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils |
| title_short | Nitrogen and dissolved organic carbon (DOC) losses from an artificially drained grassland on organic soils |
| title_sort | nitrogen and dissolved organic carbon doc losses from an artificially drained grassland on organic soils |
| url | http://www.biogeosciences.net/11/4123/2014/bg-11-4123-2014.pdf |
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