Abstract:

[Objective] Forest management is recognized as an important way to mitigate CO₂ emission from soils. Under the global warming, understanding the effects of different managements on temperature sensitivity of soil respiration is helpful to determine the response and adaptation of under-ground processes to climate change and to indentify the positive/negative feedbacks of soil respiration to climate change. [Methods] Our study included four treatments: control (Ⅰ), reclamation(Ⅱ), herbicide application (Ⅲ) and herb-chopping (Ⅳ). Trenching and litter removal were used to separate the components of soil respiration and LI-8100 was used to measure soil respiration and soil temperature at depth of 5 cm. Exponential model was employed to describe temperature sensitivity of soil respiration (Q₁₀).[Results] (1)Components of soil respiration were exponential with soil temperature at depth of 5cm; (2) Q₁₀ of total soil respiration was in an order of Winter>Summer>Spring>Autumn. Reclamation, herbicide application and herb-chopping decreased Q₁₀ of total soil respiration. (3) The order of Q₁₀ of root respiration was Summer>Winter>Spring>Autumn. All managements reduced Q₁₀ ; (4) Q₁₀ of litter respiration was in an order of Summer>Winter>Autumn>Spring. Reclamation, herbicide application and herb-chopping declined Q₁₀; (5) Q₁₀ of mineral respiration was in an order of Spring>Winter>Summer>Autumn. Reclamation increased Q₁₀ while orther two managements decreased Q₁₀. [Conclusion] Given mitigation of CO₂ emission and adaptation of soil respiration to global climate change, herbicide application may be a relatively reasonable management for Moso bamboo forest in this area.