土壤水力性质参数估计的响应界面和敏感度分析

结合单步出流实验的数值反演方法在确定土壤水力性质时会遇到解的非唯一性问题。为了减少解的非唯一性，本文使用了敏感系数和响应界面对实验设计和解的唯一性进行了分析。结果表明出流量及压力水头对于拟合参数来说都是敏感的且增加压力后参数的敏感系数也相应增加；通过对不同出流变量及其组合的响应界面分析，发现在目标函数中加入压力水头可以减少解的非唯一性，增加压力也降低了解的非唯一性。

Parameter estimation analysis of soil hydraulic properties

The non-uniqueness problem is always encountered when numerical inverse method coupling with one step outflow experiments is employed to determine the soil hydraulic properties. To reduce the non-uniqueness, the sensitivity coefficients and response surfaces were used to design the experiment and analyze the uniqueness of solution. The results showed that outflow and pressure head data were both sensitive to the parameters fitted and the sensitive coefficients increased when pressure increased. By analyzing the response surfaces of different outflow variables and their combination, the non-uniqueness was found to be reduced when pressure head data were added into objection function, and the non-uniqueness also reduced when pressure increased.