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| Titel |
Human Effects and Soil Surface CO2 fluxes in Tropical Urban Green Areas, Singapore |
| VerfasserIn |
Bernard Ng, Laure Gandois, Fuu Ming Kai, Amy Chua, Alex Cobb, Charles Harvey, Lucy Hutyra |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250072402
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| Zusammenfassung |
| Urban green spaces are appreciated for their amenity value, with increasing interest in the
ecosystem services they could provide (e.g. climate amelioration and increasingly as possible
sites for carbon sequestration). In Singapore, turfgrass occupies approximately 20%
of the total land area and is readily found on both planned and residual spaces.
This project aims at understanding carbon fluxes in tropical urban green areas,
including controls of soil environmental factors and the effect of urban management
techniques. Given the large pool of potentially labile carbon, management regimes
are recognised to have an influence on soil environmental factors (temperature
and moisture), this would affect soil respiration and feedbacks to the greenhouse
effect.
A modified closed dynamic chamber method was employed to measure total soil
respiration fluxes. In addition to soil respiration rates, environmental factors such as soil
moisture and temperature, and ambient air temperature were monitored for the site in an
attempt to evaluate their control on the observed fluxes. Measurements of soil-atmosphere
CO2 exchanges are reported for four experimental plots within the Singtel-Kranji Radio
Transmission Station (103o43’49E, 1o25’53N), an area dominated by Axonopus compressus.
Different treatments such as the removal of turf, and application of clippings were effected as
a means to determine the fluxes from the various components (respiration of soil and turf, and
decomposition of clippings), and to explore the effects of human intervention on observed
effluxes.
The soil surface CO2 fluxes observed during the daylight hours ranges from 2.835 +
0.772 umol m-2 s-1 for the bare plot as compared to 6.654 + 1.134 umol m-2 s-1 for the
turfed plot; this could be attributed to both autotrophic and heterotrophic respiration. Strong
controls of both soil temperature and soil moisture are observed on measured soil fluxes. On
the base soils, fluxes were positively correlated to soil temperature and negatively to soil
moisture. Above the grass, fluxes are negatively correlated soil temperature and positively to
soil moisture.
The measured values will be combined to carbon stock evaluation in the different
compartments to assess carbon budget for green area under different grass management in
Singapore. |
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