Fig. 2From: Soil enzyme activities as potential indicators of soluble organic nitrogen pools in forest ecosystems of Northeast ChinaRelationships between soil soluble organic N and N-acetyl-β-glucosaminidase, urease, asparaginase, and protease per unit soil organic C for the natural secondary forest and the larch plantation (n = 16, i.e., four plots × two soil depths × two forest types). **P < 0.01, significanceBack to article page