Simulation of rainfall interception process of primary korean pine forest in Xiaoxing'an Mountains by using the modified Gash model

Abstract

Primary Korean pine (Pinus koraiensis) forest is climax community of Xiaoxing忆an Mountains, in northeast of China. It has significant influence on regional ecology and hydrological environment. In order to investigate the canopy interception and allocation and evaluate forest hydrological function and benefit of virgin Korean pine forest quantitatively, positioning experiments were implemented during two rainy seasons of from 2010 to 2011 in Liangshui national nature reserve. Throughfall, stemflow and precipitation were measured and interception loss was subsequently calculated. On the basis of the observations of 21 rainfall events which collected from local weather station and forest stand respectively, we stimulated canopy interception process of virgin Korean pine forest in the Xiaoxing忆an Mountains using the modified Gash model. The mesured values of total preciptation, througfall, stemflow, and canopy interception loss in virgin Korean pine forest of Xiaoxing忆an Mountains were 514. 1 mm, 373. 19 mm, 8. 02 mm, and 132. 43 mm, respectively, during the study period. Throughfall and stemflow were all significantly positively correlated with precipitation (P <0. 01). The simulated values of throughfall, stemflow, and interception loss by modified Gash model were 370. 91 mm, 16. 14 mm, and 130. 07 mm respectively. Simulation value of throughfall was 2. 28 mm lower than the actual value, with a relative error of 1. 75% , while simulation value of stemflow was 8. 12 mm higher than the measured value, with a relative error of 50. 3%. The simulated value of canopy interception loss was 2. 35 mm lower than the actual value, with a relative error of 1. 81%. The

Influence of Rainfall on Canopy Interception in Mixed Broad-Leaved—Korean Pine Forest in Xiaoxing’an Mountains, Northeastern China

“…Many studies have been conducted on the ecohydrological processes of the mixed forest, such as rainfall partitioning (e.g., canopy interception, throughfall, and stemflow) [19,20] and the hydrological function (e.g., rainfall, canopy interception, evapotranspiration, and runoff) [21]. The rainfall-simulated experiment and Gash model were commonly used approaches to estimating the canopy interception of the mixed forest [22,23], but the simulated result was more proper for annual rainfall than for a single rainfall event. Therefore, the relationships between event-based rainfall amount, rainfall intensity, and canopy interception of the mixed forest type are still not clear.…”