溪頭孟宗竹林降雨截留特徵

Abstract

Abstract Bamboo forests accounted for 4.4% and 7% of the forests in Asia and Taiwan, respectively. Rainfall interception is an important process in the water cycle; however, little is known about rainfall interception in the bamboo forests compared with the other forest types. The aims of this study are to utilize the moso bamboo forest to: 1) quantify the spatial variability of the throughfall (Tf) and stemflow (Sf), 2) estimate the interception (Ic) of the forest after the Tf and Sf have been quantified, and 3) characterize Ic in the Taiwan bamboo forest by comparing it to other forests in the literature. This study estimated Ic in the bamboo forest in Xitou Nature Education Area in the National Taiwan University Experimental Forest by measuring precipitation (P), Tf and two methods of Sf from June 8, 2012 to August 1, 2013 on the events basis with the interval of two to three weeks and compared the estimations with those of other forests. Method 1 estimated the stand scale of Sf by measuring the crown project area (CPA) in the 10 samples and measuring the Sf in the 10 samples. The second method estimated the stand scale of Sf by using a linear relationship between DBH of the 10 samples and measuring the Sf in the the 10 samples. In addition, spatial variations were evaluated using the coefficient of variation (CV). CV in Tf was 20.3%. The CV decreased with increases in precipitation. While, CV in Sf was 37% which little decreased with increase in P. Total precipitation (P) during the period from July 26, 2012 to August 1, 2013 was 3826.2 mm, the total Tf was estimated as 81% of the total P. Sf in methods 1 and 2 were estimated as 4.5% and 9.1% of the total P, respectively, whereas the Ic was estimated as 14.5% and 9.9% of the total P, respectively. Compared with the other forests in the Mainland of China, Japan, and Taiwan, the bamboo forests showed a relatively higher Tf and Sf value, and a relatively smaller Ic value than other forest types.