人类干扰对闽江河口湿地土壤碳、氮、磷生态化学计量学特征的影响

为了阐明湿地土壤生态化学计量学特征对人类干扰的响应,对闽江河口湿地受到人类不同程度干扰的芦苇沼泽、草地、滩涂养殖地、耕地、池塘养殖地和干扰恢复的弃耕地土壤的碳、氮、磷生态化学计量学特征进行了测定与分析.结果表明,土壤C/N、C/P和N/P比均表现出随着干扰程度的增大而降低,即轻度干扰的芦苇沼泽和草地(25.53、156.06、6.11和27.58、158.99、5.78)中度干扰的滩涂养殖地(25.02、96.90、3.87)高度干扰的耕地和池塘养殖地(17.55、46.19、2.65和22.30、57.51、2.62);与高度干扰的耕地相比,干扰恢复的弃耕地土壤C/N、C/P和N/P比有所提高(19.95、63.81和3.18);影响土壤C/N、C/P和N/P比的因子随干扰程度的变化而改变;土壤C/N比表现出随着干扰程度和土壤深度的变化相对较小,C/P和N/P比的变异性相对较大;碳与养分比对土壤碳储量具有良好的指示作用.

Effect of Human Disturbance on Ecological Stoichiometry Characteristics of Soil Carbon, Nitrogen and Phosphorus in Minjiang River Estuarine Wetland

To clarify responses of soil ecological stoichiometry in wetland to human disturbance, the ecological stoichiometry characteristics of carbon, nitrogen and phosphorus elements of soil in Phragmites australis marsh, grassland, flat breed aquatics, cropland, pond aquaculture after human disturbance and abandoned cropland after human disturbance restoration in Minjiang River estuary were analyzed. The results showed: averaged values of C/N, C/P, N/P ratios were declined as the human disturbance increment, which appeared that Phragmites australis marsh, grassland (lower human disturbance, 25.53, 156.06, 6.11 and 27.58, 158.99, 5.78) were bigger than flat breed aquatics (medium human disturbance, 25.02, 96.90, 3.87), and flat breed aquatics (medium human disturbance) were bigger than cropland, pond aquaculture (higher human disturbance, 17.55, 46.19, 2.65 and 22.30, 57.51, 2.62). Compared with cropland, C/N, C/P, N/P ratios in abandoned cropland (human disturbance restoration) were (19.95, 63.81, 3.18) higher. The influencing factors were changed with the human disturbance intensity. Soil C/N ratios showed relatively small variation between different human disturbance and soil depth, while C/P and N/P ratios showed a high heterogeneity. The ratio of carbon to nutrition had preferable indication for carbon storage.