Response of a Bornean Rainforest to the Climatic Changes Imposed by ENSO During 2009-2015
Abstract
Tropical rainforests belong to the most important biomes, as they are one of the largest terrestrial carbon sinks and also a consequent source of latent energy. Furthermore, they will be among the first ecosystems to undergo climatic changes in the near future. Understanding how they will response to those changes is essential. El Niño-Southern Oscillation (ENSO) is an opportunity to study ecosystem response under real climatic change conditions. Transpiration (Tr), net ecosystem exchange (NEE) and heat fluxes were measured with an eddy covariance system in a natural rainforest in Sarawak, Borneo. Meteorological and soil moisture observations were also conducted. This region does not have phase-locked dry periods and seasonal variations of both air temperature and solar radiation are small. However, it is directly impacted by ENSO events. During the study period, from November 2009 to December 2015, two events were selected : La Niña 2010-2011 and El Niño 2014-2016. Normal conditions were assumed as a third "neutral" period. Comparisons of measured flux and meteorological drivers between the three periods were carried out, and analysis of environmental controls, as canopy conductance (gc) were made. Rainfall distributions varied between the three periods, with the highest mean daily precipitation in La Niña. Latent heat (LE), Tr, NEE and gc had the largest mean daily value during this period too. Tr and NEE were smaller in El Niño than in neutral conditions, while there was no significative difference in the mean value of gc between those two periods. LE was unexpectedly higher during El Niño than in neutral period.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMGC43H1622M
- Keywords:
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- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCESDE: 0426 Biosphere/atmosphere interactions;
- BIOGEOSCIENCESDE: 0428 Carbon cycling;
- BIOGEOSCIENCESDE: 1630 Impacts of global change;
- GLOBAL CHANGE