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| Titel |
Nitrogen deposition along an elevation gradient in Taiwan |
| VerfasserIn |
Chia-Yi Li, Chih-Hsin Cheng |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250138243
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| Publikation (Nr.) |
 EGU/EGU2017-1202.pdf |
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| Zusammenfassung |
| Taiwan is one of the areas that has high nitrogen deposition. The deposition of nitrogen,
however, is not homogeneous, but rather is heterogeneous with high spatial and
temporal variation. In this study, we evaluated nitrogen deposition along an elevation
gradient ranged from 100 m which was closest to the agricultural and industrial areas
to 1800 m which was located in the mid-elevation mountainous areas to identify
how elevation affects nitrogen deposition under an annual determination. Bulk
precipitation was collected using the funnel apparatus mounted on a post 1.5 m above
ground level in each study site (n=7), and collected weekly or every other weekly
depending on the frequency of rainfall events. Cations (K+, Na+, Ca+2, Mg+2, and
NH4+), anions (F−, Cl−, SO4−2, and NO3−), pH and electric conductance (EC) of
precipitation water were analyzed. The results indicated a significant trend along the
elevation gradient. Volume-weighted mean concentration (μg L−1) and deposition
amounts (kg ha−1) of based cations, anions, NH4+, pH and EC decreased with
the elevation, whereas hydrogen ion increased with elevation. The mean ratio of
NH4+-N/NO3−-N for all study sites was 2.87 and no clear elevation trend existed. However,
a relatively high ratio of NH4+-N/NO3−-N was found in the sites with elevation less
than 500 m during the periods between March and May, suggesting the seasonal
agricultural input in these sites. Deposition of NH4+-N, NO3−-N, and total inorganic N
were 12 – 25, 4 – 10, and 16 – 37 kg N ha−1, respectively, during the period from
January 2016 to August 2016. Higher nitrogen deposition is expected for the whole
2016 year. High nitrogen deposition poses an ecological threat in Taiwan and more
research is warranted to understand how nitrogen deposition could be detrimental to
environment. |
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