民勤绿洲不同演化阶段白刺灌丛沙堆表面土壤理化性质研究

Soil Physical and Chemical Properties of Nitraria tangutorun Nebkhas Surface at Different Development Stages in Minqin Oasis

以民勤绿洲作为研究区域,对不同演化阶段灌丛沙堆表面土壤样品进行了采集和分析。结果表明,随着灌丛沙堆的不断演化,土壤性质发生了显著的变化。不同演化阶段灌丛沙堆表面颗粒组成仍以砂粒为主,从雏形阶段到稳定阶段,砂粒含量逐渐减少,在稳定阶段达到最小,pH值和砂粒的变化趋势一致,粉砂、粘粒、有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾含量增加,在稳定阶段均达到最大;灌丛沙堆活化后,其砂粒含量和pH值重新出现增加趋势,而粉砂和粘粒的含量开始减少,有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾含量也迅速下降;除稳定阶段迎风坡和背风坡有机质、全氮和全磷含量差异比较显著外,其他演化阶段不同坡向粒度和养分差异均不显著;有机质、全氮、速效氮的含量在灌丛沙堆演化过程中变幅最大,全磷和速效磷次之,全钾和速效钾的变幅最小。

Taking the Minqin oasis as the research region, soil surface samples of nebkhas in different development stages were collected and the soil physical and chemical properties were analyzed, in which the soil particle composition, organic matter, total N, total P, total K, rapidly available N, rapidly available P, rapidly available K were included. The results showed that with the development of nebkhas, soil properties have experienced a significant variation. Soil mechanical composition is mostly composed by sand, from the rudimental stage to the stabilizing stage, sand content and pH value were gradually decreased, to the lowest in the stabilizing stage, clay, silt, organic matter, total N, total P, total K, rapidly available N, rapidly available P and rapidly available K have showed a increased trend, to the highest in stabilizing stages. After the degradation of nebkhas, the sand content and pH value increased while clay, silt content, organic matter, total N, total P, total K, rapidly availableN, rapidly available P and rapidly available K have the same decreasing trend, except soil organic matter, total N, rapidly available N between the windward and leeward slopes in stabilizing stages have showed a significant difference, soil properties have no significant difference in other development stages between windward and leeward slopes. The content of organic matter, total N, rapidly available N have showed the greatest variation in the development of nebkhas, then the total P and rapidly available P, total K and rapidly available K were the least.