Abstract
The form and functioning of peatlands depend strongly on their
hydrological status, but there are few data available on the hydraulic
properties of tropical peatlands. In particular, the saturated hydraulic
conductivity (K) has not previously been measured in neotropical peatlands. Piezometer slug tests were used to measure K
at two depths (50 and 90 cm) in three contrasting forested peatlands in
the Peruvian Amazon: Quistococha, San Jorge and Buena Vista. Measured K at 50 cm depth varies between 0.00032 and 0.11 cm s−1, and at 90 cm, it varies between 0.00027 and 0.057 cm s−1. Measurements of K
taken from different areas of Quistococha showed that spatial
heterogeneity accounts for ~20% of the within-site variance and that
depth is a good predictor of K. However, K did not vary
significantly with depth at Buena Vista and San Jorge. Statistical
analysis showed that ~18% of the variance in the K data can be
explained by between-site differences. Simulations using a simple
hydrological model suggest that the relatively high K values
could lead to lowering of the water table by >10 cm within ~48 m of
the peatland edge for domed peatlands, if subjected to a drought lasting
30 days. However, under current climatic conditions, even with high K,
peatlands would be unable to shed the large amount of water entering
the system via rainfall through subsurface flow alone. We conclude that
most of the water leaves these peatlands via overland flow and/or
evapotranspiration.
Original language | English |
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Pages (from-to) | 3373-3387 |
Number of pages | 15 |
Journal | Hydrological Processes |
Volume | 28 |
Issue number | 9 |
Early online date | 8 Jul 2013 |
DOIs | |
Publication status | Published - 30 Apr 2014 |
Keywords
- Ombrotrophic
- Floristic composition
- Aguajal
- Peatland
- Model simulation
- Subsurface water flow