Modelling rainfall interception loss in forest restoration trials in Panama

Abstract

A modified Liu analytical model of rainfall interception (I c ) by tree canopies was evaluated using rainfall, throughfall and stemflow data collected from forest restoration trials in the Republic of Panama. The model uses an introduced approach to estimating the water storage capacities of tree boles, which has a more realistic physical basis than earlier iterations of the Liu model. Study species (Acacia mangium, Gliricidia sepium, Guazuma ulmifolia, Ochroma pyramidale, and Pachira quinata) were selected on the basis of differing leaf size and crown characteristics. Significant interspecific differences in both observed and simulated cumulative interception loss were found, with A. mangium intercepting more rainfall than other species. Errors between calculated and modelled cumulative I c ranged from C6Ð3% to C30Ð5%, with modelled I c always being the larger term. During-event evaporation rates from the study trees were positively related to tree height, crown area, and basal diameter. Crown area and the storage capacity of tree boles were negatively correlated. The results of a sensitivity analysis suggested that the modified model was most sensitive to variations in during-event evaporation rate. The implications of the model's sensitivity to during-event evaporation and the importance of this mechanism of interception loss are discussed, while suggestions are provided that may lead to further improvements to the analytical model.

Throughfall and stemflow vary seasonally in different land‐use types in a lower montane tropical region of Panama

“…Clear impacts of vegetation structure on rainfall partitioning like those described by Hodnett et al ., , Crockford and Richardson, , Huber and Iroumé, , Fleischbein et al ., , Brauman et al ., , Carlyle‐Moses et al ., and Mair and Fares, were not found in this study. Species diversity and LAI values for different land‐use types did not explain differences in throughfall, but this may because different species influence throughfall in different ways (Park and Cameron, ).…”

Evolution of forest precipitation water storage measurement methods

“…Carlyle‐Moses et al . () developed an improvement to S t estimates for individual trees using a metric called the stemflow funnelling ratio (Herwitz, ). The funnelling ratio ( F ) is basically an areal comparison of P with stemflow generated by the outlying crown portions: where P s is the stemflow volume and B is the trunk basal area (Herwitz, ).…”

Measurement and modeling of canopy water partitioning in a reforested landscape: The Ganaraska Forest, southern Ontario, Canada

“…The Liu model is much less demanding than other interception models such as that of Rutter et al (1971) and Gash (1979) in terms of data requirements; yet it has been found to produce results of comparable accuracy to these models (Liu, 2001;Carlyle-Moses and Price, 2007). The Liu model also incorporates exponential wetting of the canopy, which more accurately reflects the actual process of canopy wetting than alternatives such as the Gash (1979) model which requires that canopy storage capacity be satisfied before drainage occurs (Carlyle-Moses et al, 2010). The reformulated model is:…”

“…The Liu model has also not been as widely used as other interception models (Muzylo et al, 2009), and this study will evaluate its performance in estimating interception for forest types other than those in which it has already been applied (e.g. Liu, 2001;Carlyle-Moses and Price, 2007;Carlyle-Moses et al, 2010). Should it prove to be satisfactory, the Liu model could then be used to predict how reforestation and the transition to a mixed hardwood forest will affect water partitioning in forest stands of differing type and age in the GF.…”