摘要
运用马尔可夫过程的理论 ,建立了土壤非饱和流条件下 ,模拟硝态氮通过土层运移的随机模型 .模型把时间可变系统假设为由紧密相连的时间均质情况相接而成 ,使得运用马尔可夫过程成为可能 ,在给定土壤水流量及汇源项转移强度的土壤层次中 ,给出了硝态氮溶质的统计分布 .模型将随机过程与确定性过程相结合 ,在计算各土层间的转移概率时考虑了硝态氮的作物吸收、淋洗、硝化和反硝化等主要过程 ,并用相关函数修正 N素转化关系 .在褐土农田土壤非饱和流条件下 ,用微区试验对该模型运行效果进行了验证 ,结果显示模拟计算值与实测值之间吻合性较好 ,说明模型可以用于相似类型区 ,预测和评价土壤 -作物系统中硝态氮溶质的运移行为 .
Based on the theory of Markov Process, a stochastic model is established to simulate the interlayer transport of NO - 3 N in a cinnamon soil with unsaturated water flow. This model converts the temporally variable system into a system closely resembles the time homogeneous case, and makes Markov Process model applicable. The probability distribution of NO - 3 N is given for each soil layer under a given soil water flow and a given transport intensity of source and sink. In calculating the transport probability from one soil layer to another one, the main processes of NO - 3 N uptake and its leaching, nitrification and denitrification are considered, and the relationship between N transformations is calibrated with correlation function. A micro plot experiment on NO - 3 N transport is installed to verify the results obtained from simulation study, which shows a satisfactory agreement between measured and simulated results, indicading that the model can be used in similar areas to predict and evaluate the behavior of NO - 3 N transport in soil crop system.
出处
《应用生态学报》
CAS
CSCD
1997年第1期49-54,共6页
Chinese Journal of Applied Ecology
基金
国家"九五"科技攻关项目
关键词
田间条件
农业生态学
土壤非饱和流
硝态氮
Field condition, Unsaturated soil waterflow, Nitrate nitrogen, Solute transport.
