三江平原典型小叶章湿地土壤中铵态氮水平运移规律研究  

Study on Horizontal Movement of Ammonium Nitrogen in Typical Calamagrostis Angustifolia Wetland Soils of Sanjiang Plain

作　　者：孙志高[1] 刘景双[1] 张党玉 顾康康[1] 王明全[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所 [2]荣成市第三十四中学,山东荣城264304

出　　处：《水土保持学报》2006年第5期87-91,125,共6页Journal of Soil and Water Conservation

基　　金：中国科学院知识创新工程重要方向项目(KZCX3-SW-332);国家自然科学基金项目(90211003)资助

摘　　要：选择三江平原小叶章湿地不同水分带上的两种土壤类型（草甸沼泽土和腐殖质沼泽土）作为研究对象，以NH4Cl为示踪剂，模拟研究了铵态氮在土壤中的水平运移过程。结果表明，两种土壤各土层的铵态氮浓度和水平运移速率均与运移距离呈显著负相关（P〈0．01），并随运移距离的增加呈一阶指数衰减曲线变化。各土层的铵态氮水平运移主要由其对于铵态氮吸附的饱和程度来决定，而运移速率主要受浓度梯度、水势梯度及土壤基质势的控制；两种土壤各土层的铵态氮水平运移速率与土壤含水量大多呈显著正相关（P〈0．05），并随含水量的增加而呈指数增长曲线变化；两种土壤各土层的铵态氮浓度均受土壤水分扩散率的影响，二者大多呈显著正相关（P〈0．05），除草甸沼泽土0～20cm土层的铵态氮浓度随水分扩散率的升高呈Boltzmann曲线变化外，其它土层及腐殖质沼泽土的各土层均随其升高呈指数增长曲线变化；草甸沼泽土要比腐殖质沼泽土的相应土层更有利于铵态氮的水平运移，二者不同土层物理性质的显著差异是导致其铵态氮浓度、水平运移速率随运移距离、土壤含水量及水分扩散率的变化而发生分异的重要原因，而湿地水文条件可能对于二者物理性质的塑造作用有着重要影响。Choosing the two typical soils （Meadow marsh soil and Humus marsh soil）, located in different moisture gradient in Calamagrostis angustifolia wetland of Sanjiang Plain, as study objects. The ammonium nitrogen （NH4^＋- N） horizontal movement processes of the two typical soils were studied by simulative experiment with NH4Cl tracer. The results showed that the NH4^＋-N concentrations and horizontal movement velocities of the two typical soils had significantly negative correlations with movement distances （ p〈0.01）, and they all varied in first-order exponential decay curves. The NH4^＋-N horizontal movement was mainly determined by NH4^＋ -N saturation of soil adsorption, and the velocity was controlled by concentration gradient, water potential gradient and soil matrix potential. The NH4^＋- N movement velocities had significantly positive correlations with soil moisture contents （ p〈0.05）, and they varied in exponential growth curves. The NH4^＋ -N concentrations of the two typical soils were all affected by soil moisture diffusivities, and they had significantly positive correlations （ p〈0.05）. The NH4^＋-N concentrations of the two typical soils all varied in exponential growth curves as the increase of soil moisture diffusivities except 0-20 cm solum of meadow marsh soil （Boltzmann curves）. In conclusion, the solums of meadow marsh soil were more favored to the movement of NH4^＋-N than those of humus marsh soil. The significant differences in physical properties of the two typical soils were the important reason to induce the differentiations of NH4^＋- N concentration and horizontal movement velocity as the change of movement distance, soil moisture content or soil water diffusivity, and the different hydrographic conditions in C. angustifolia wetland probably had important influence on physical properties of the two typical soils.

关 键 词：铵态氮 水平运移 小叶章湿地 三江平原 

分 类 号：X144[环境科学与工程—环境科学] S143.12[农业科学—肥料学]