DOI: 10.5194/hess-21-651-2017
Scopus记录号: 2-s2.0-85011301109
论文题名: The canopy interception-landslide initiation conundrum: Insight from a tropical secondary forest in northern Thailand
作者: Sidle R ; C ; , Ziegler A ; D
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2017
卷: 21, 期: 1 起始页码: 651
结束页码: 667
语种: 英语
Scopus关键词: Forestry
; Landslides
; Moisture
; Pore pressure
; Pressure distribution
; Rain
; Soil moisture
; Soils
; Tropics
; Water
; Wetting
; Wind
; Canopy interception
; Non-linear relationships
; Pore-water pressures
; Shallow landslide
; Soil moisture dynamics
; Temporal intervals
; Total event rainfalls
; Tropical secondary forests
; Precipitation (meteorology)
; forest canopy
; interception
; landslide
; monsoon
; pore pressure
; porewater
; rainfall
; secondary forest
; soil moisture
; throughfall
; timescale
; tropical forest
; Thailand
英文摘要: The interception and smoothing effect of forest canopies on pulses of incident rainfall and its delivery to the soil has been suggested as a factor in moderating peak pore water pressure in soil mantles, thus reducing the risk of shallow landslides. Here we provide 3 years of rainfall and throughfall data in a tropical secondary dipterocarp forest characterized by few large trees in northern Thailand, along with selected soil moisture dynamics, to address this issue. Throughfall was an estimated 88ĝ€% of rainfall, varying from 86 to 90ĝ€% in individual years. Data from 167 events demonstrate that canopy interception was only weakly associated (via a nonlinear relationship) with total event rainfall, but not significantly correlated with duration, mean intensity, or antecedent 2-day precipitation (API2). Mean interception during small events (≤ ĝ€35ĝ€mm) was 17ĝ€% (n ĝ€ Combining double low line ĝ€135 events) compared with only 7ĝ€% for large events (>ĝ€35ĝ€mm; n ĝ€ Combining double low line ĝ€32). Examining small temporal intervals within the largest and highest intensity events that would potentially trigger landslides revealed complex patterns of interception. The tropical forest canopy had little smoothing effect on incident rainfall during the largest events. During events with high peak intensities, high wind speeds, and/or moderate-to-high pre-event wetting, measured throughfall was occasionally higher than rainfall during large event peaks, demonstrating limited buffering. However, in events with little wetting and low-to-moderate wind speed, early event rainfall peaks were buffered by the canopy. As rainfall continued during most large events, there was little difference between rainfall and throughfall depths. A comparison of both rainfall and throughfall depths to conservative mean intensity-duration thresholds for landslide initiation revealed that throughfall exceeded the threshold in 75ĝ€% of the events in which rainfall exceeded the threshold for both wet and dry conditions. Throughfall intensity for the 11 largest events (rainfallĝ€ Combining double low line ĝ€65-116ĝ€mm) plotted near or above the intensity-duration threshold for landslide initiation during wet conditions; 5 of the events were near or above the threshold for dry conditions. Soil moisture responses during large events were heavily and progressively buffered at depths of 1 to 2ĝ€m, indicating that the timescale of any short-term smoothing of peak rainfall inputs (i.e., ≤ ĝ€1ĝ€h) has little influence on peak pore water pressure at depths where landslides would initiate in this area. Given these findings, we conclude that canopy interception would have little effect on mitigating shallow landslide initiation during the types of monsoon rainfall conditions in this and similar tropical secondary forest sites. © Author(s) 2017. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/79274
Appears in Collections: 气候变化事实与影响
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作者单位: Sustainability Research Centre, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, QLD, Australia; Department of Geography, National University of Singapore, AS2, #03-01, 1 Arts Link, Kent Vale, Singapore, Singapore
Recommended Citation:
Sidle R,C,, Ziegler A,et al. The canopy interception-landslide initiation conundrum: Insight from a tropical secondary forest in northern Thailand[J]. Hydrology and Earth System Sciences,2017-01-01,21(1)