作　　者： ; ; ; (肖荣波）; (王刚）; (邓一荣）;

机构地区： 广东工业大学

出　　处： 《生态学报》 2016年第22期7462-7471,共10页

摘　　要： 城市绿地土壤呼吸作用深刻影响着城市生态系统碳循环过程,强化城市绿地土壤呼吸速率(Rs)的变化特征及其影响因素的研究,可揭示绿地在城市生态系统碳循环过程中的作用,为优化布局城市绿地和实现低碳排放目标提供科学依据。以广州市海珠湖公园的疏林、灌丛和草地3种典型植被类型的土壤为研究对象,于2013年11月-2014年10月采用静态箱—气相色谱法对公园绿地Rs进行跟踪观测。结果表明:海珠湖公园城市绿地在干湿季节中Rs差异显著;干季Rs较低且波动幅度较小疏林、灌丛和草地的凡变化范围分别为(1.66±0.18)-(3.26±0.20)μmol m^(-2)s^(-1)、(1.27±0.15)-(3.67±0.16)μmol m^(-2)s^(-1)和(1.94±0.08)-(6.82±1.13)μmol m^(-2)s^(-1);湿季Rs较高且波动幅度较大,疏林、灌丛和草地的Rs变化范围分别为(3.53±0.46)-(13.81±1.31)μmol m^(-2)s^(-1)、(2.82±0.22)-(12.72±1.16)μmol m^(-2)s^(-1)和(2.80±0.30)-(9.83±0.96)μmol m^(-2)s^(-1)。T_(10)和VWC_(10)均对土壤呼吸过程有重要的影响,进一步通过回归分析得出,土壤10cm处温度(T_(10))和体积含水量(VWC_(10))分别解释Rs时间变异的40%左右和10-24%左右。T_(10)和VWC_(10)相互影响、共同作用于土壤呼吸过程,双因素复合模型的解释能力较单因素模型明显提高,均在50%以上,复合模型为Rs=α·exp(β·T_(10)+γ·VWC_(10))。干湿季土壤呼吸的温度敏感性(Q_(10))有明显差异,湿季的Q_(10)比干季的分别高0.44、0.70和0.46。 Soil respiration is a major component of the carbon cycle in terrestrial ecosystems,and small changes have a significant effect on CO_2 concentration in the atmosphere.Previous studies from different terrestrial ecosystems have confirmed that soil respiration is related to both global climate change and the carbon cycle.However,many studies have focused on non-urban ecosystems,such as forests,farmlands,and grasslands,while fewer studies have examined soil respiration in urban green-space ecosystems.In particular,few studies have addressed whether soil respiration is affected by different vegetation types in urban green-space ecosystems.This research explored soil respiration rate（Rs） in three different vegetation types in urban green-space,to provide basic scientific data on the contribution of urban green-space to the carbon cycle in urban ecosystems.Results will also facilitate the optimization of landscape patterns in urban greenspaces to reduce carbon emissions.In this study,Rs of three representative vegetation types（woodland,scrubland,and grassland） were investigated in Haizhu Lake Park of Guangzhou,Guangdong Province,China.From November 2013 to October 2014,we measured Rs monthly using a static chamber and gas chromatography,while simultaneously measuring soil temperature and volumetric water content.Results showed a significant difference in Rs between the wet and dry seasons.A relatively lower Rs,with less fluctuation,was noted in the dry season：（1.66±0.18）-（3.26±0.20） μmol m-（-2） s-（-1） for woodland,（1.27±0.15）-（3.67±0.16） μmol m-（-2） s-（-1） for scrubland,and（1.94±0.08）-（6.82±1.13） μmol m^-2s^-1 for grassland.Conversely,a relatively higher Rs,with much more fluctuation,was noted in the wet season：（3.53±0.46）-（13.81±1.31） μmol m^-2s^-1 for woodland,（2.82±0.22）-（12.72±1.16） μmol m-（-2） s-（-1） for scrubland,and（2.80±0.30）-（9.83±0.96） μmol m-（-2） s-（-1） for grassland.In addition,environmental factor

关 键 词： 土壤呼吸速率 城市绿地 植被类型 土壤温度 土壤体积含水量

领　　域： [理学] [理学]