Abstract:Acid phosphatase kinetics can reflect phosphorus (P) transformation under different soil substrates. Forest restoration types influence ecosystem services, such as soil fertility maintenance and nutrient cycling. Litter and roots are two main ways that different forest restoration types affect P maintenance and cycling. In the background of climate change and human activity, litter and roots have complex impacts on ecosystem services such as soil P maintenance and P cycling. However, there are few reports on the effects of litter and roots on soil acid phosphatase kinetics under different forest restoration types. Detritus input and removal treatment (DIRT) experiment was conducted in three typical forest restoration types (introduced black pine [Pinus thunbergii Parl.] plantations, native oriental oak [Quercus variabilis Bl.] plantations, and natural secondary forests) in the Yimeng Mountains area. DIRT included double litter treatment, litter removal treatment, roots removal treatment, no inputs treatment, and control. Soil samples were collected on August 21st, 2022, which was 7 years and 9 months after DIRT EXPERIMENT was conducted.The effects and mechanisms of changing litter and roots input on soil acid phosphatase dynamics were analyzed. The acid phosphatase activities were as follows: (1) the activity of acid phosphatase and Vmax (the maximum reaction velocity) under the three forest restoration types showed the order of double litter>control>litter removal>roots removal >no inputs treatment. (2) Km(half-saturation constant) and Vmax/Km (catalytic efficiency) were relatively stable and less susceptible to changes in litter and root inputs. However, Vmax was easily affected, double litter treament significantly increased Vmax in the soils of oriental oak plantations, litter removal, roots removal and no inputs treatments significantly reduced Vmax of the soil of black pine plantations. (3) The feedback of available P content regulated the acid phosphatase activity. The acid phosphatase activity (substrate at moderate concentrations of 80-160 μmol/L) and Vmax were significantly and positively correlated with available P content. The soil nitrogen availability and moisture content significantly affected the soil acid phosphatase activity of the three forest restoration types. The influence of roots on acid phosphatase kinetics was larger than litter. In the background of climate change, the soil organic P transformation capacity of the introduced black pine plantations was unstable and easily disturbed, followed by the natural secondary forests, with the native oriental oak plantations being the most stable. These results provide insights into forest restoration, climate change responses, and human activities related to forest fire prevention and litter collection in warm temperate areas.