Response of throughfall exclusion on soil respiration in natural evergreen broad-leaved forest in rainy area of western China

Abstract

A situ experiment was conducted to detect, the effects of throughfall exclusion on soil respiration in evergreen broad-leaved forest in Rainy Area of Western China. We respectly set both three 3 ∗3m quadrates for control(CK),reducing 5% throughfall(W1), reducing 10% throughfall(W2), reducing 20% throughfall(W3), and reducing 50% throughfall(W4) on November 2013, located in Yucheng District of Yaan City, Sichuan Province. We detected the dynamics of soil respiration rate and other environmental factors from January to November 2014. The results indicated that: (1)One year later, W1 treatment had no significant effect on soil respiration of evergreen broad-leaved forest, W2 treatment increased the soil respiration rate of evergreen broad-leaved forest, while W3 and W4 treatments inhibited significantly (p<0.05); (2) W1, W3 and W4 treatments' cumulative soil CO2 efflux rates were less than the CK 3.03%, 12.26% and 26.67%, while W2 treatment increased by 11.17% compared with CK; (3) W2 treatment may reduce the temperature sensitivity of soil respiration, W1, W3 and W4 treatments may increase the temperature sensitivity of soil respiration. In summary, throughfall exclusion significantly affected the soil respiration of broad-leaved forest, changed the temperature sensitivity of soil respiration.