探究黄河湿地包头段——南海湿地不同地被类型土壤有机碳组分空间分布特征及碳库稳定性,了解南海湿地土壤有机碳分布情况,为南海湿地土地管理和生态系统保护提供理论依据.以裸地为参照,选取芦苇( Phragmites australis )、旱柳( Salix matsudana)、玉米( Zea mays)和向日葵( Helianthus annuus)4种典型地被类型,采集0~10、10~20、20~30、30~40、40~50、50~60 cm共6个层次土壤,测定土壤活性有机碳及其占总有机碳的比例,分析不同地被类型碳库稳定性差异;采用ArcGIS 10.2软件绘制空间插值制图分析有机碳组分含量水平差异.结果表明,在垂直方向,有机碳组分含量均呈现随土壤深度增加而降低的趋势,裸地、玉米、向日葵、旱柳、芦苇总有机碳质量分数垂直变化范围分别为4.25~6.67、5.86~10.26、5.86~11.58、5.31~14.60、6.57~16.71 g·kg-1,活性有机碳质量分数垂直变化范围分别为1.22~2.47、2.02~5.32、2.10~6.08、1.97~6.12、1.52~6.17 g·kg-1,各分层总有机碳和活性有机碳含量变异系数均在10%~100%之间,属中等变异,南海湿地碳库稳定性不高.在水平方向,土壤总有机碳含量表现为芦苇＞旱柳＞向日葵＞玉米＞裸地,活性有机碳占总有机碳含量的比例分别为:裸地28.73%~37%,平均值为32.06%;玉米34.53%~51.85%,平均值为42.41%;向日葵35.86%~52.5%,平均值为43.26%;旱柳31.22%~41.92%,平均值为35.08%;芦苇23.14%~36.91%,平均值为28.08%,表现为向日葵＞玉米＞旱柳＞裸地＞芦苇,向日葵和玉米平均值最高,碳库稳定性最低,芦苇碳库稳定性最高.可以认为,南海湿地土壤有机碳属稳定碳库,但稳定性不高;土壤有机碳稳定性表现为向日葵＜玉米＜旱柳＜裸地＜芦苇;人类活动对天然湿地进行开发利用之后,其碳库稳定性下降.%To explore the Baotou section of the Yellow River wetland——the spatial distribution characteristics and carbon stock stability of different types of soil organic carbon, and to understand the distribution of soil organic carbon in the wetland of the South China Sea, so as to provide a theoretical basis for the land management and ecosystem protection in the wetland of the South China Sea. Taking the naked ground as the reference, four typical types of Phragmites australis, Salix matsudana, Zea mays and Helianthus annuus were selected. Layers of soil with a depth of 0~60 cm (0~10, 10~20, 20~30, 30~40, 40~50, 50~60 cm) were collectedto measure active organic carbon and its proportion to total organic carbon, so as to analysis the stability of different types of carbon stocks. ArcGIS 10.2 software was used to draw spatial interpolation maps to analyze the differences in the level of content of the organic carbon groups. The results showed that the content of organic carbon in the vertical direction had a decreasing trend with increasing soil depth. The vertical variation range of total organic carbon in bare land, Zea mays, Helianthus annuus, Salix matsudana, and Phragmites australis was 4.25~6.67, 5.86~10.26, 5.86~11.58, 5.31~14.60 and 6.57~16.71 g·kg-1, respectively. The active organic carbon was 1.22~2.47, 2.02~5.32, 2.10~6.08, 1.97~6.12, 1.52~6.17 g·kg-1, respectively. The coefficients of variation of total organic carbon and active organic carbon in each layer were 10%~100%, which was a moderate variation. The stability of the carbon pool in the wetland of the South China Sea was not high. In the horizontal direction, the order of the total organic carbon contents in the soil was as follows: Phragmites australis＞Salix matsudana＞Helianthus annuus＞Zea mays＞bare land, and the ratio of total active organic carbon to total organic carbon showed that: bare land was 28.73% to 37%, with an average of 32.06%; Zea mays was 34.53%~51.85%, with an average of 42.41%; Helianthus annuus was 35.86%~52.5%, with an average of 43.26%; Salix matsudana was 31.22%~41.92%, with an average of 35.08%; and Phragmites australis was 23.14%~36.91%, with an average of 28.08 %, expressed as Helianthus annuus＞Zea mays＞Salix matsudana＞bare land＞Phragmites australis, Helianthus annuus and Zea mays had the highest average values, the stability of carbon stocks was the lowest, and the stability of Phragmites australis carbon stocks was the highest. Conclusion: the soil organic carbon in the wetland of South China Sea is a stable carbon pool, but its stability is not high. The stability of soil organic carbon is expressed as Helianthus annuus＜Zea mays＜Salix matsudana＜bare land＜Phragmites australis. After the activities developed and utilized the natural wetland by human, the stability of the carbon pool has decreased.
展开▼
