Figure 7

(A) ammonia-monooxygenase abundance of AOB and (B) ammonia-monooxygenase abundance of AOA, estimated by qPCR for the following treatments: (T1) native species without Periandra mediterranea and no invasion; (T2) native species plus P. mediterranea and no invasion; (T3) native species plus P. mediterranea and ≤50% invasion by Melinis minutiflora; (T4) native species plus P. mediterranea and >50% invasion. Means values ± SE (standard error) with different letters are significantly different according to Kruskal-Wallis and Nemenyi tests at 5% confidence level (p ≤ 0.05).