[模拟氮沉降对中国西部多雨地区慈竹林土壤呼吸的影响]

[Effects of simulated nitrogen deposition on soil respiration in a Neosinocalamus affinis plantation in rainy area of west China].

作者信息

Li Ren-hong, Tu Li-hua, Hu Ting-xing, Zhang Jian, Lu Yang, Liu Wen-ting, Luo Shou-hua, Xiang Yuan-bin

机构信息

Sichuan Province Key Laboratory of Forestry Ecological Engineering, College of Forestry, Sichuan Agricultural University, Ya'an 625014, Sichuan, China.

出版信息

Ying Yong Sheng Tai Xue Bao. 2010 Jul;21(7):1649-55.

PMID:20879519

Abstract

From December 2007 to November 2008, an in situ experiment was conducted to study the effects of simulated nitrogen deposition on the soil respiration in a Neosinocalamus affinis plantation in Rainy Area of West China. Four treatments were installed, i.e., 0 (CK), 50, 150, and 300 kg N x hm(-2) x a(-1), and soil respiration rate was measured by infrared gas analyzer. In the test plantation, soil respiration rate had a distinct seasonal fluctuation, with the highest (3.36 +/- 0.20 micromol x m(-2) x s(-1)) by the end of July and the lowest by the end of February (0.33 +/- 0.07 micromol x m(-2) x s(-1)). There was a significant exponential relationship (P<0.001) between soil respiration rate and soil temperature, and the temperature at 10 cm soil depth explained 91.6% of the seasonal change of soil respiration. However, less relationship was observed between soil respiration rate and soil moisture content (R2 = 0.0758). From June to November 2008, the contribution of root respiration to total soil respiration ranged from 46% to 59%. The annual release amount of CO2 in treatments 50, 150, and 300 kg x hm(-2) x a(-1) was 23.6% , 46.7%, and 50.5% lower than that in CK (2.17 x 10(4) kg x hm(-2)), and the Q10 value of soil respiration rate in treatments 0, 50, 150, and 300 kg x hm(-2) x a(-1) was 3.72, 3.51, 2.95, and 2.71, respectively.

摘要

2007年12月至2008年11月，在中国西部多雨地区的一片慈竹林中进行了一项原位试验，以研究模拟氮沉降对土壤呼吸的影响。设置了4种处理，即0（对照）、50、150和300 kg N·hm⁻²·a⁻¹，并用红外气体分析仪测定土壤呼吸速率。在试验林中，土壤呼吸速率有明显的季节性波动，7月底最高（3.36±0.20 μmol·m⁻²·s⁻¹），2月底最低（0.33±0.07 μmol·m⁻²·s⁻¹）。土壤呼吸速率与土壤温度之间存在显著的指数关系（P<0.001），10 cm土壤深度处的温度解释了土壤呼吸季节变化的91.6%。然而，土壤呼吸速率与土壤含水量之间的关系较弱（R² = 0.0758）。2008年6月至11月，根系呼吸对土壤总呼吸的贡献在46%至59%之间。50、150和300 kg·hm⁻²·a⁻¹处理下的年CO₂释放量分别比对照（2.17×10⁴ kg·hm⁻²）低23.6%、46.7%和50.5%，0、50、150和300 kg·hm⁻²·a⁻¹处理下土壤呼吸速率的Q10值分别为3.72、3.51、2.95和2.71。