The Non-Growing Season Fluxes Of Greenhouse Gas Emission From Eight Temperate Forests In Northeastern China

Non-growing season soil greenhouse gas emission may play an important role in the forest ecosystem carbon and nitrogen cycle.However,it is not clear about the effect of the disturbance from logging primary forests after the restoration of afforestation and succession pathways on soil greenhouse gas emissions during non-growing season.In order to reveal the effects of afforestation and succession on non-growing season greenhouse gas emission fluxes,and their Global warming potential and annual contribution rate.The non-growing season fluxes of CO2,CH4 and N2O emissions from eight kinds of forest types(two plantations(Korean pine plantation?pinus koraiensis??HR?and larch plantation?Larix gmelinii??LR??51a?,five natural secondary forests?Hardwood forest?Fraxinus mandshurica,Juglans mandshurica and Phellodendron amurense??YK?,Betula platyphylla forest?Betula platyphylla??BH?,Populous davidiana forest?Populus davidiana??SY?,Mixed deciduous forests?ZM?,Mongolian oak forest?Quercus mongolica??MGL??61-67a?,and primary Korean pine and broad-leaved mixed forest?YS??150a??were measured simultaneously by using a static closed chamber and gas chromatograph technique,as well as their associated environmental factors?such as temperature,soil moisture,carbon and nitrogen content,etc..?in temperate Maoer mountain of China.The results shown that:?1?The fluxes of CO2 emission from the non-growth season of 8 temperate forest types?15.97?57.86 mg·m₂·h-1?showed that which from 2 kinds of plantations and 4 kinds of secondary forests?except MGL?were significantly higher than those of the primary forest by 1.1?1.5 times and 1.4?2.6 times?P<0.05?;?2?Their non-growth season fluxes of CH4 absorption?9.13?69.74 ug·m-2·h-1?showed that three secondary forests?YK,SY,ZM?were significantly higher than that of the primary forest by 1.5 to 1.8 times?P<0.05?,but that from two plantations decreased by 0.5 to 0.6 times compared to the primary forest?P>0.05?;?3?Their non-growth season fluxes of N2O emission?7.68?40.55 ug·m-2·h-1?showed that two plantations and three secondary forests?YK,SY,ZM?significantly higher than the primary forest by 1.1?2.9 times and 1.2?1.9 times?P<0.05?;?4?Soil CO2 emissions and CH4 absorption in the primary forest non-growth season were mainly controlled by temperature,humidity,pH value,organic carbon content,snow thickness or ammonium nitrogen,and N2O emissions was only controlled by temperature and ammonium nitrogen.Soil CO2,CH4 and N2O fluxes in the non-growth season of plantation and secondary forests were generally controlled only by temperature,snow cover thickness and soil pH values.?5?the afforestation and succession made the annual contribution rate of soil CH4 uptake during non-growing season?12.3%?30.2%?decreased by 2.8%?10.0%?except SY?,but made the annual contribution rate of CO2 and N2O emssions?4.8%-12.5%and 7.0%?63.6%?increased by 3.1%?7.7%or 3.0%?56.6%,respectively,compared to the primary forest;?6?Afforestation and succession?51?67 years later?caused the greenhouse gas warming potential of non-growing soil?71.16-250.64 g CO2·m-2·Yr-1?significantly increased by 1.31.9 times and 1.2?2.5 times?P<0.05?,compared to the primary forest.Therefore,the effects of the disturbance from logging primary forests on non-growing greenhouse gas emissions have not been completely eliminated after the restoration of afforestation and succession pathways to the medium term?51-67 a?.