意思是，土壤在一天内，温度最低和温度最高之间的幅度，也就是一天内的温差，真心在帮你期待采纳，
随深度增加，土壤温度日振幅逐渐减小，位相落后也愈加明显。Daily amplitude of soil temperature gradually decreased and the phase lagged more obviouslywith the increase of soil depth.
