They are the primary creatures who break up clay; without them, the breaking up of the soil would create "fault lines" affecting the progress of the work of the secondary creatures who do the same task--bacteria and microbes. This would slow down the improvement of soil quality.
如果沒有它，土壤的分解將造成「斷層」，影響細菌、微生物等次級分解者「工作」的進行，土壤品質的改良也可能延緩。