杉木林地表各呼吸贡献及其对气象因子的响应

Contribution of different components of soil respiration and their reaction to meterorological factors in Chinese fir plantation

采用断根法和红外气体分析仪IRGA测定相结合区分和测定了杉木人工林林地土壤呼吸3种来源组分:矿质土层呼吸、根呼吸和凋落物层呼吸的动态。阐述土壤不同呼吸组分对土壤总呼吸的贡献,以及主要气象因子对土壤各呼吸组分的影响。研究结果表明,矿质土层呼吸、根呼吸和凋落物层呼吸对对土壤总呼吸的贡献分别为56.7%,22.0%,21.4%。气温和土壤呼吸为指数关系,蒸发量是表征土壤呼吸的有效指标,但全年降雨量集中在低温季节会对根系呼吸产生抑制作用。提出评价降雨量对土壤呼吸的影响不仅考虑降雨量的多少更要注意其分配情况。

Trenching and infrared gas exchange analyzer approaches are used to determine the soil respiration by three components, e.g. mineral soil respiration （Rs）, root respiration （Rr） and litter respiration （R1）, in Chinese fir plantation in Huitong, subtropical China for one year.. Our purpose is to partition the contribution of different respiration components to soil respiration and the effects of major meteorological factors on soil respiration components. The results show that Rs, Rr ,R1 accounts for 56.7%, 22.0%, 21.4% respectively. The soil respiration is positively correlated with air temperature and evaporation. Excess rainfall distributed at the low-temperature season result in decreasing respiration of root. It is noted that participation plays a significant role in affecting soil respiration due to its amounts as well as distribution all the year.