Study On Characteristics Of Soil Carbon Respiration In Larix Gmelinii Forests

In this study, Dahurian Larch forest soil respiration were measured by the static chamber / alkali absorption method.Eventually,dynamics changes and relationship between impact factors of the larch forest soil carbon emission process was got via trenching method and root- excised method .The study provided data for the carbon sources/ carbon sinks of Dahurian Larch forest soil and zonal data for the global carbon balance and carbon cycle research.The results showed that:(1)The Dahurian Larch forest soil respiration showed significant correlation either with heterotrophic respiration and autotrophic respiration,but the relevance of heterotrophic respiration was higer than autotrophic respiration. RH / RS varied from 42.34% to 75.23%, and the average is 61.21%; RA / RS varied from 24.78% to 57.66%, and the average is 38.79%.Those indicated that the contribution rate of heterotrophic respiration was greater than the rate of autotrophic respiration.(2)The Dahurian Larch forest soil respiration and its components showed a diurnal and seasonal variation .Diurnal variation of soil respiration showed a single peak, while the diurnal variation of autotrophic respiration and heterotrophic respiration were similar with the soil respiration,but the trend wasn't significant changes.The respiration rate of soil respiration and its summer components was significantly higher than in spring and autumn.(3) Through correlation analysis between soil respiration and its components of the Dahurian Larch forest and the temperature,air temperature and soil temperature in 10cm soil layer were being exponential relationship with soil respiration.(4)There was a positive correlation ,which was close to a significant correlation(p= 0.066>0.05),between Dahurian Larch forest soil respiration rate and soil moisture.However,there was not significant correlation between heterotrophic respiration and autotrophic respiration and soil moisture.(5) To find the forest litter influence on soil respiration and its components,the experiment double and remove forest litter.There wasn't significant effct on the treatment of doubling and removal forest litter.After those treatment,the correlation was closer between soil respiration and heterotrophic respiration,and also significantly increased Q10 value of soil respiration and heterotrophic respiration,which was significantly increased soil respiration and heterotrophic respiration of temperature sensitivity.