城市沿江芦苇湿地土壤呼吸动态及影响因子分析

Soil Respiration and Controlling Factors at Phragmites communis Community in Riverside Wetlands

采用Li-8100土壤碳通量测定仪对闽江沿岸芦苇湿地土壤呼吸的昼夜变化和季节变化进行测量,结果表明:在最高水位土壤表面未淹水的状态下,不同季节的土壤呼吸日动态没有一致的规律性,土壤温度和土壤体积含水量不是土壤呼吸日变化的主要影响因子;而在最高水位土壤表面淹水的状态下,水位对土壤呼吸强度有一定影响:当土壤表面被淹没时,土壤呼吸强度约为0;当水位下降时,土壤呼吸强度增加.土壤呼吸的季节变化呈单峰形式,5 cm处土壤温度仅能解释土壤呼吸季节变化的49.4%,而土壤体积含水量对土壤呼吸季节变化无显著影响.

Soil respiration dynamics of Phramites communis in Minjiang riverside wetlands was measured by Li-8100 automated soil CO2 flux system. The results showed that soil respiration dynamics, under the condition of inundation, was different among seasons; soil temperature and soil content were not the impact factors in diurnal respiration; water level had impacts on soil respiration when the soil was flooded; the seasonal patterns of soil respiration rate were obvious by showing a single peak; and, in annual scale, soil respiration was significantly correlated with soil temperature at 5 cm depth （whose contribution to soil respiration reached 49. 4% ）, but there was no relationship between soil respiration rate and water content.