Kuo Teng-chih explains that there is a calcium line in the body of the creatures which adjusts the acidity level in the soil; the amount of "positive" nutrients like potassium, magnesium, phosphorus, and calcium will be increased in soil which goes through a worm "out-of-body experience." The heavy metal zinc will be somewhat reduced.
郭登志的實驗發現，蚯蚓身體內有鈣腺，可以調整土壤的酸鹼值；經過它體內的泥土，鉀、磷、鎂、鈣等「良性」養份會增加，重金屬鋅則會略為減少。