Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics
Changing land use in subtropical and tropical catchments to farmland can result in higher nitrogen (N) loss to aquatic ecosystems. Here, we developed a lumped water and N balance model to estimate regional N losses to creeks at catchment scale within understudied subtropical catchments in Australia....
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-10-01
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| Series: | Frontiers in Earth Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2020.00347/full |
| _version_ | 1819114024386691072 |
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| author | Mithra-Christin Hajati Shane White Nils Moosdorf Nils Moosdorf Isaac R. Santos Isaac R. Santos |
| author_facet | Mithra-Christin Hajati Shane White Nils Moosdorf Nils Moosdorf Isaac R. Santos Isaac R. Santos |
| author_sort | Mithra-Christin Hajati |
| collection | DOAJ |
| description | Changing land use in subtropical and tropical catchments to farmland can result in higher nitrogen (N) loss to aquatic ecosystems. Here, we developed a lumped water and N balance model to estimate regional N losses to creeks at catchment scale within understudied subtropical catchments in Australia. The conceptual water balance model CoCa-RFSGD was extended by the nitrogen mass balance in top and subsoil by adding nitrogen cycle transformation estimates depending on meteorological, soil, and land-use properties. The model estimates the impact of pristine and agricultural land use on catchment-wide water quality using only low-order creek samples as water quality measurements of nitrate and nitrite (NOx) with increased model performance with increased agricultural coverage. The model revealed that an agricultural proportion of 3% in the study site drove a 3.5-fold increase of N losses to creeks and a 6.7-fold increase of N losses to the atmosphere compared to catchments without agriculture. Agricultural land use lost 92 kg-N ha−1, 85% of which evaded to the atmosphere and 15% was discharged via surface waters. A change from forest to cleared land may increase the total denitrification potential of a catchment. Overall, our lumped model provides a simple but effective tool to upscale local aquatic water quality measurements to the catchment scale, allowing for assessment of changing land use on aquatic N loads in areas with limited data availability. |
| first_indexed | 2024-12-22T04:38:43Z |
| format | Article |
| id | doaj.art-fb229eb1060f4b39b2e7b6c88207f8fd |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-12-22T04:38:43Z |
| publishDate | 2020-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-fb229eb1060f4b39b2e7b6c88207f8fd2022-12-21T18:38:49ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632020-10-01810.3389/feart.2020.00347515279Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the SubtropicsMithra-Christin Hajati0Shane White1Nils Moosdorf2Nils Moosdorf3Isaac R. Santos4Isaac R. Santos5Leibniz Centre for Tropical Marine Research (ZMT), Bremen, GermanyNational Marine Science Center, Southern Cross University, Lismore, NSW, AustraliaLeibniz Centre for Tropical Marine Research (ZMT), Bremen, GermanyInstitute of Geosciences, Kiel University, Kiel, GermanyNational Marine Science Center, Southern Cross University, Lismore, NSW, AustraliaDepartment of Marine Sciences, University of Gothenburg, Gothenburg, SwedenChanging land use in subtropical and tropical catchments to farmland can result in higher nitrogen (N) loss to aquatic ecosystems. Here, we developed a lumped water and N balance model to estimate regional N losses to creeks at catchment scale within understudied subtropical catchments in Australia. The conceptual water balance model CoCa-RFSGD was extended by the nitrogen mass balance in top and subsoil by adding nitrogen cycle transformation estimates depending on meteorological, soil, and land-use properties. The model estimates the impact of pristine and agricultural land use on catchment-wide water quality using only low-order creek samples as water quality measurements of nitrate and nitrite (NOx) with increased model performance with increased agricultural coverage. The model revealed that an agricultural proportion of 3% in the study site drove a 3.5-fold increase of N losses to creeks and a 6.7-fold increase of N losses to the atmosphere compared to catchments without agriculture. Agricultural land use lost 92 kg-N ha−1, 85% of which evaded to the atmosphere and 15% was discharged via surface waters. A change from forest to cleared land may increase the total denitrification potential of a catchment. Overall, our lumped model provides a simple but effective tool to upscale local aquatic water quality measurements to the catchment scale, allowing for assessment of changing land use on aquatic N loads in areas with limited data availability.https://www.frontiersin.org/articles/10.3389/feart.2020.00347/fullmodeling soil nitrogen cyclingsubtropicshorticulturenitrate leakageeutrophication |
| spellingShingle | Mithra-Christin Hajati Shane White Nils Moosdorf Nils Moosdorf Isaac R. Santos Isaac R. Santos Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics Frontiers in Earth Science modeling soil nitrogen cycling subtropics horticulture nitrate leakage eutrophication |
| title | Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics |
| title_full | Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics |
| title_fullStr | Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics |
| title_full_unstemmed | Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics |
| title_short | Modeling Catchment-Scale Nitrogen Losses Across a Land-Use Gradient in the Subtropics |
| title_sort | modeling catchment scale nitrogen losses across a land use gradient in the subtropics |
| topic | modeling soil nitrogen cycling subtropics horticulture nitrate leakage eutrophication |
| url | https://www.frontiersin.org/articles/10.3389/feart.2020.00347/full |
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