杨树人工林碳循环对淹水的响应

The Carbon Cycle's Response to Flooding in the Poplar Forest

本文采用涡度相关方法对安徽怀宁杨树人工林的碳通量进行监测,得到微气象数据和通量数据。通过坐标旋转、密度校正和数据插补处理提高数据质量。选取2005年9月淹水期间的数据,分六个阶段进行分析,得到以下结果:(1)在半小时尺度上,在淹水期表观量子效率α随着土壤含水量SWC上升而降低;在未淹水期最大,为-0.0023μmol photon-1;退水期最低,为-0.00122mg CO2 μmol photon-1,退水后恢复到-0.00168mg CO2 μmol photon-1;α在淹水中2期降低速率最大,在整个淹水期间α的恢复速率是大于降低速率的。(2)生态系统总初级生产力(GEP)在淹水后不断降低,未淹水期为8.0gCm-2day-1,退水后为4.7 gCm-2day-1,在淹水中2期降幅是最大的达到了16%。(3)生态系统呼吸(Reco)在完全被水淹的第一天降到最低,仅为2.2 gCm-2day-1;由于温度的影响其变化规律比较复杂,在淹水中2期的变化幅度是最大的;退水后Reco为4.2 gCm-2day-1恢复到未淹水前的87%。(4)淹水期净生态系统CO2交换量(NEE)的变化表现为先上升后下降的趋势,在淹水中1期最大为-4.2 gCm-2day-1,退水后最低,为0.6 gCm-2day-1是未淹水前的17%。

This article uses the method of eddy covariance to monitor the Poplar tree planted forest＇ s carbon flux in Anhui Huaining, obtaining the micro meteorological data and the flux data. Through coordinate revolving, the rejection as well as interpolation processing improves the data quality. To the needing of my research,we choose data in September, 2005, and divides six stages to carry on the analysis, obtains the following resuh：（1） in a half hour criterion, during the flooding time Apparent quantum efficiency （ct） reduces along with the soil water content（SWC） rises; α in the time of not been flooded is - 0.0023 mgCO2 μ mol photon^-1 and is the biggest,;The time when SWC is reducing, α is - 0.00122mgCO2 μ tool photon^-1 and is the lowest;After drawing back the water, α restores to - 0.00168 mgCO2 μ tool photon^-1; Phase 2 of flooded tine has the biggest reducing speed, in the whole time α ＇ s speed of restoring is bigger than the speed of reducing.（2） the ecosystem primary productive （GEP） is reduces unceasingly around the flooded time, GEP in the time of not been flooded is 8.0gCm^-2day^-1, and after drawing back the water it is 4.7 gCm^-2day^-1, The reducing speed of GEP in Phase 2 of flooded tine has achieved 16% and is the biggest.（3） the ecosystem breath （Reco） in the first day of flooded is only 2.2 gCm^-2day^-1; Because of the temperature ＇s influence Reco＇ s change rule is quite complex, in Phase 2 of flooded time Reco ＇s range of changing is biggest; After drawing back the water, Reco is 4.2 gCm^-2day^-1 restores 87% of the time of not been flooded..（4） The tendency of the NEE ＇s change around the time of flooding shows dropping after rising, NEE in Phase 1 of flooded time is - 4.2 gCm^-2day^-1;After drawing back the water, NEE is 0.6 gCm^-2day^-1 and is the lowest ,is only 17% of that in the time of nut been flooded.