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据黄河三角洲的碱蓬群落、芦苇群落、柽柳群落和棉田地的土壤有机质含量差异,分析不同植被类型下土壤有机质的分布差异,结果表明:表土层中,芦苇群落的有机质远远高于其他三种群落,大小顺序为芦苇群落>柽柳群落>棉田地>碱蓬群落土,这与芦苇的密集性、有效的聚肥作用有关。土壤剖面显示,40cm以上土层的有机质含量明显要比下层土的高。其中,芦苇群落有机质以0-5cm土层含量最高,柽柳是多年生灌木,紧凑的株型有效的保护冠层下的凋落物,使其表层土壤有机质仅次于芦苇;而棉田地土壤有机质最高值并非出现在表层,而是出现在5-10cm的土层,这与棉田地掠夺式土地利用有关;碱蓬是生长于贫瘠土壤的一年生草本,其有机质含量在10-20cm土层较高。人为干扰因素的影响下棉田地的变异系数明显大于自然植物群落的土壤变异系数,说明人为因素在一定程度上增加了土壤表层有机质含量的差异。
According to the difference of soil organic matter content in the communities of Suaeda sibirica community, Phragmites communis community, Tamarix community and cotton field in the Yellow River Delta, the distribution of soil organic matter under different vegetation types was analyzed. The results showed that the organic matter of Phragmites communis community was much higher than the other three The order of population and size was Phragmites australis community> Tamarix spp> cotton field> Suaeda sylvite community soil, which was related to the intensive and effective co-fertilizer effect of Phragmites communis. The soil profile shows that the content of organic matter in the soil above 40cm is obviously higher than that in the lower soil. Among them, the Phragmites australis community has the highest content of organic matter in 0-5cm layer, Tamarix is a perennial shrub, the compact plant type can effectively protect the litter under the canopy, making the topsoil organic matter second only to reed, while the highest soil organic matter It does not appear on the surface layer but appears in the 5-10cm soil layer, which is related to predatory land use in cotton fields. Suaeda is an annual herb growing in poor soil with higher organic matter content in 10-20cm soil layer. The coefficient of variation of cotton field was significantly higher than that of natural plant community under the influence of human disturbance factors, indicating that human factors increased the difference of organic matter content of soil surface to a certain extent.