Key Laboratory of Coastal Environment Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Chunhui Road 17, Laishan District, Yantai, 264003, Shandong, China.
Environ Manage. 2012 Jul;50(1):39-49. doi: 10.1007/s00267-012-9869-7. Epub 2012 May 11.
Vegetation type and density exhibited a considerable patchy distribution at very local scales in the Yellow River Delta, due to the spatial variation of soil salinity and water scarcity. We proposed that soil respiration is affected by the spatial variations in vegetation type and soil chemical properties and tested this hypothesis in three different vegetation patches (Phragmites australis, Suaeda heteroptera and bare soil) in winter (from November 2010 to April 2011). At diurnal scale, soil respiration all displayed single-peak curves and asymmetric patterns in the three vegetation patches; At seasonal scale, soil respiration all declined steadily until February, and then increased to a peak in next April. But, the magnitude of soil respiration showed significant differences among the three sites. Mean soil respiration rates in winter were 0.60, 0.45 and 0.17 μmol CO(2) m(-2) s(-1) for the Phragmites australis, Suaeda heteroptera and bare soil, respectively. The combined effect of soil temperature and soil moisture accounted for 58-68 % of the seasonal variation of winter soil respiration. The mean soil respiration revealed positive and linear correlations with total N, total N and SOC storages at 0-20 cm depth, and plant biomass among the three sites. We conclude that the patchy distribution of plant biomass and soil chemical properties (total C, total N and SOC) may affect decomposition rate of soil organic matter in winter, thereby leading to spatial variations in soil respiration.
植被类型和密度在黄河三角洲的非常小的尺度上表现出相当大的斑块分布，这是由于土壤盐分和水分缺乏的空间变化所致。我们提出，土壤呼吸受到植被类型和土壤化学性质空间变化的影响，并在冬季的三个不同植被斑块（芦苇、盐角草和裸地）中检验了这一假设（2010 年 11 月至 2011 年 4 月）。在日尺度上，土壤呼吸在三个植被斑块中均显示出单峰曲线和不对称模式；在季节尺度上，土壤呼吸均稳步下降，直到 2 月，然后在下一年 4 月增加到峰值。但是，三个地点的土壤呼吸幅度有显著差异。芦苇、盐角草和裸地在冬季的平均土壤呼吸速率分别为 0.60、0.45 和 0.17 μmol CO(2) m(-2) s(-1)。土壤温度和土壤水分的综合效应解释了冬季土壤呼吸季节变化的 58-68%。三个地点的平均土壤呼吸与总氮、总氮和 SOC 储量与 0-20cm 深度呈正线性相关，与植物生物量呈正线性相关。我们得出结论，植物生物量和土壤化学性质（总 C、总 N 和 SOC）的斑块分布可能会影响冬季土壤有机质的分解速率，从而导致土壤呼吸的空间变化。
