 |
| Titel |
The impact of land-use change from forest to oil palm on soil greenhouse gas and volatile organic compound fluxes in Malaysian Borneo |
| VerfasserIn |
Julia Drewer, Melissa Leduning, Deirdre Kerdraon-Byrne, Emma Sayer, Justin Sentien, Ute Skiba |
| Konferenz |
EGU General Assembly 2017
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250142830
|
| Publikation (Nr.) |
 EGU/EGU2017-6495.pdf |
|
|
|
|
|
| Zusammenfassung |
| Monocultures of oil palm have expanded in SE Asia, and more recently also in Africa and
South America, frequently replacing tropical forests. The limited data available clearly show
that this conversion is associated with a potentially large greenhouse gas (GHG) burden. The
physical process of land-use change, such is felling, drainage and ploughing can significantly
increase emissions of N2O and soil CO2 respiration and decrease CH4 oxidation rates in
the short term; and in the long-term regular nitrogen applications will impact in
particular soil N2O fluxes. Little is known about volatile organic compound (VOC)
fluxes from soil and litter in tropical forests and their speciation or about the links
between GHG and VOC fluxes. VOC emissions are important as they directly and
indirectly influence the concentrations and lifetimes of air pollutants and GHGs. For
example, oxidation of VOCs generate tropospheric ozone which is also a potent
GHG. Within ecosystems, monoterpenes can mediate plant-microbe and plant-
interactions and protect photosynthesis during abiotic stress. However, little is known
about monoterpene composition in the tropics - a widely recognized major global
source of terpenoids to the atmosphere. These knowledge gaps make it difficult for
developing countries in the tropics, especially SE Asia, to develop effective mitigation
strategies.
Current understanding of soil GHG fluxes associated with land-use change from forest to
oil palm is not sufficient to provide reliable estimates of their carbon footprints and
sustainability or advice on GHG mitigation strategies. To provide the necessary data we have
installed a total of 56 flux chambers in logged forests, forest fragments and mature and young
oil palm plantations as well as riparian zones within the SAFE landscape in SE Sabah
(Stability of Altered Forest Ecosystems; http://www.safeproject.net). Soil respiration rates,
N2O, CH4 and VOC fluxes together with soil moisture, pH, mineral and total C and N were
measured over a two year period. Additionally the effects of changes in forest litter
diversity on soil properties were investigated using mesocosms. For this experiment
leaf litter was transplanted into different forest types and oil palm plantations of
different stand ages to simulate the change in litter-fall caused by changes in above
ground plant composition. Laboratory incubations using soil and litter from the field
sites provide additional detailed data on soil properties, carbon storage capacity
and microbial activity to identify potential mechanisms for the field observations. |
|
|
|
|
|
|