Abstract:Understanding the characteristics of soil ecological stoichiometry is important for predicting nutrient changes, plant productivity, and ecosystem functions in different ecosystems. Forest regeneration is an important approach to accomplish sustainable development of mid-subtropical forest ecosystems. Therefore, in this thesis, three contrasting ways of forest regeneration were selected for study in the Chenda state-owned forestry farm in Fujian; namely, Castanopsis carlesii forest (SF), human-assisted naturally regenerated Castanopsis carlesii forest (AR), and Cunninghamia lanceolata plantation (CF). Additionally, different physical and chemical soil properties were examined, along with three types of soil enzymes, and eco-enzymatic stoichiometry was calculated. Our results revealed the following:1) the soil contents of total nitrogen, total phosphorus, ammonium nitrogen, and moisture were the most significant in the human-assisted naturally regenerated Castanopsis carlesii forest(P < 0.05), while soil content of available phosphorus was the highest in the Cunninghamia lanceolata plantation(P < 0.05); 2) according to the eco-enzymatic stoichiometry calculation, the state of soil microorganisms were restricted by nitrogen availability in the human-assisted naturally regenerated Castanopsis carlesii forest, and by phosphorus availability in the Cunninghamia lanceolata plantation; 3) as redundancy analysis showed, the content of soil moisture and ammonium nitrogen are important environmental factors that influence the eco-enzymatic stoichiometry of different forest regeneration methods. Generally, human-assisted natural regeneration is more beneficial to soil mineral nitrogen accumulation, while artificial forest regeneration is conducive to accumulation of available phosphorus in the soil, which may be related to the tree species selected for afforestation. Soil eco-enzymatic stoichiometry is more likely to be driven by soil moisture content and nutrient availability than by soil stoichiometry.