a significant trendP=0.022
During the survey period, community biomass increased in May and June, and decreased from July to September, with a significant trend in August (loss rate 2.61g year -1 ; Supplementary Figure 3 (a); F 1,28 = 28.3, P=0.022; R 2 = 0.18) and September (loss rate 3.97g year -1 ; Supplementary Figure 3 (a); F 1,24 = 24.9, P=0.003; R 2 = 0.34).