Response of hydrological processes of Pinus massoniana forest to rainfall in southern Jiangsu Province of eastern China

ObjectiveFrom September 2012 to August 2013, through the monitoring of Pinus massoniana forest by rainfall, canopy interception, trunk runoff, and penetrating rain, exploring the different rainfall levels, rain tightness, masson pine canopy interception, trunk runoff, and the characteristics and linkages of the changes in the rain. This paper aims to provide a scientific basis for the sustainable management of the masson pine forest in the hilly area of southern Jiangsu Province of eastern China.

MethodThe 34-year-old Pinus massoniana forest was selected, and the applicability of the Gash model was established and verified using the RG3-M tipping bucket self-recording rain gauge, self-made trunk runoff collection device, collecting sump to collect rainfall, trunk runoff, and penetrating rain data.

Result(1) Rainfall is mainly concentrated in May–August, and there was a significant linear correlation between canopy interception, trunk runoff, penetrating rainfall and rainfall, and trunk flow rate and penetration rate with rainfall intensity and rainfall level. The increase was on the rise, but the interception rate was reversed. (2) The maximum interception rate of Pinus massoniana forest appeared at the minimum rainfall level (< 1.0 mm), the rain intensity was < 1.0 mm/h, and the maximum trunk runoff rate appeared in moderate rainfall (≥ 50 mm) and rain intensity of 1.5−2.0 mm/h and the maximum rainfall penetration occurred in the maximum rainfall level (≥ 50.0 mm) and the rain intensity range of 1.5−2.0 mm/h. The results showed that the hydrological process of Pinus massoniana forest had good response to rainfall and rainfall intensity was a key factor affecting the hydrological process in Pinus massoniana forest. (3) Quantitative analysis of rainfall redistribution law by Gash mode by calculating relevant parameters, the obtained simulated values were in good agreement with the measured values.

ConclusionThe water holding capacity of the canopy part and trunk of Masson pine forest was 1.21 and 0.1 mm, respectively, and the minimum rainfall of trunk runoff was 4.86 mm. This study can provide a clear and scientific reference for the interception process of Pinus massoniana forest, and provide reliable data and theoretical basis for forest ecological hydrological function in the hilly area of southern Jiangsu Province of eastern China.