Fig. 4From: Plastic film mulching with ridge planting alters soil chemical and biological properties to increase potato yields in semiarid Northwest ChinaEffects of plastic film mulching treatments for potato on a urease activity, b catalase activity, c alkaline phosphatase activity, d sucrase activity, and e protease activity. Different lowercase letters indicate significant differences for the same treatment on different sample dates (P < 0.05), and asterisks indicate significant differences among treatments on the same sample date (P < 0.05). FP, flat plot without film mulching; FPM, flat plot with film mulching; RPHM, ridge planting with half mulch; RPFM, ridge planting with full mulchBack to article page