Mann-Kendall 方法是一种非参数统计检验方法。非参数检验方法也称无分布检验，其 优点是不需要样本遵从一定的分布，也不受少数异常值的干扰，更是用于类型变量和顺序变 量，计算也比较方便。-Mann-Kendall method is a non-parametric statistical tests. Non-parametric test method, also known as non-distribution test, the advantage is not required