The Influence From Burning Treatment To Soil Respiration Of Several Artificial Forests In Short Term

Soil respiration is one of the main methods to discharge carbon dioxide into the atmosphere from terrestrial ecosystem. And it is also an important part of the carbon cycle between terrestrial ecosystem and the atmosphere. Previous studies are mainly for forest ecological system and with the natural fire disturbance conditions. But research on soil respiration after prescribed burning has not been reported very often. City forestry demonstration base is an important factor of city ecosystem carbon cycle. Based on that, this study selected in the experimental forest farm of Northeast Forestry University, take the method of small-scale prescribed burning to typical forest in the experimental forest farm as the research object. The study is to research the influence about the variation of soil respiration in short term after prescribed burning, In order to further develop the response mechanism of large-scale prescribed burning ecosystems and provide scientific basis for the research on ecosystem carbon cycle.The results were as follows:(1) The soil respiration rate’s average value of three types of forest control samples and burned samples in the short-term were:The Rs average value of Be tula platyphylla suk forests control sample was 4.52μmol·m-2·s-1 and the Rh average value was 3.52μmol·m-2·s-1. The Rs average value of Be tula platyphylla suk forests burned sample was 5.05μmol·m-2·s-1 and the Rh average value was 3.98μmol·m-2·s-1. The Rs average value of Quecrus mongolica forests control sample was 4.00μmol·m-2·s-1 and the Rh average value was 2.28μmol·m-2·s-1. The Rs average value of Quecrus mongolica forests burned sample was 2.80μmol·m-2·s-1 and the Rh average value was 2.56μmol·m-2·s-1 . The Rs average value of Larix gmelinii forests control sample was 2.53μmol·m-2·s-1 and the Rh average value was 2.05μmol·m-2·s-1. The Rs average value of Larix gmelinii forests burned sample was 3.12μmol·m-2·s-1 and the Rh average value was 2.18μmol·m-2·s-1 . Compared with the three types of forest control and fired samples, the Be tula platyphylla suk forests soil respiration rate increased by 10%, the Quecrus mongolica forests soil respiration rate decreased by 30%, the Larix gmelinii forests soil respiration rate increased by 14%, three types of control and burned forest samples of soil heterotrophic respiration rate did not have significant changes. Contribution of root respiration rate was significantly lower. And Quecrus mongolica forests samples decreased the most obviously.(2) The ranges of variation of soil temperature and Q10 of the three forest types were as follows:The Be tula platyphylla suk forests:soil temperature of total soil respiration for 16.3-21.9℃, Q10 for 2.89. soil temperature of heterotrophic respiration for 16.0-23.3℃, Q10 for 3.67; the Quecrus mongolica forests:soil temperature of total soil respiration for 14.3-21.7 ℃, Q10 for 6.05, soil temperature of heterotrophic respiration for 13.8-21.6℃, Qio for 2.59; the Larix gmelinii forests:soil temperature of total soil respiration for 14.2-20.1℃, Qio for 3.19, soil temperature of heterotrophic respiration for 14.6-20.2℃, Q10 for2.23.(3) In this study, the prediction model of soil respiration taking into account soil temperature and humidity and their interaction effect, explained 41.2% and 51.1% of Rs and Rh changes of the control samples of Be tula platyphylla suk forests, explained 57.7%% and 33.6% of Rs and Rh changes of the burned samples of Be tula platyphylla suk forests, explained 45.8% and 22.0% of Rs and Rh changes of the control samples of Quecrus mongolica forests, explained 12.5% of Rs changes of the burned samples of Quecrus mongolica forests, explained 9.5% and 22.4% of Rs and Rh changes of the control samples of Larix gmelinii forests, explained 17.6% of Rs changes of the burned samples of Larix gmelinii forests. The Rh of the burned samples of Quecrus mongolica and Larix gmelinii could not take into account soil temperature and humidity.