东北阔叶红松林能量平衡特征

采用涡度相关法,结合小气候观测,对东北阔叶红松林的能量平衡特征进行了研究。结果表明,森林全年获得的辐射能量为2.3×109J/m2,平均净辐射(Rn)强度为72.1 W/m2,12月最小,平均为5.8W/m2,6月最大,平均为127 W/m2。除了受太阳高度角的支配,Rn对中小尺度天气变化响应显著。非生长季,森林主要能量支出项为感热通量(H),约占Rn的72%,H最大值出现在5月份;生长季,主要能量支出项为潜热通量(LE),约占Rn的60%,LE最大值出现在7月份。全年因蒸散消耗的能量为1.2×109J/m2,占净辐射的52%,森林蒸散的水量为493mm,占降水量的88%。波文比β近似呈U字型变化,其值受森林物候变化影响显著,在非生长季平均值约为3.0,生长季为0.5左右。土壤热通量(G)在非生长季表现为能量平衡方程的收入项,约占有效能量的5.0%;生长季表现为支出项,约占有效能量的4.0%,其变化过程与土壤温度梯度及叶面积指数密切相关。长白山通量观测站能量平衡收支闭合度为86%,不闭合的原因有待于进一步的研究。

Characteristic of the energy balance in broad-leaved Korean pine forest of northeastern China

As a part of the ChinaFlux program,components of energy balance fluxes were measured continuously over a broad-leaved Korean pine forest in northeastern China from January to December in 2003.Sensible fluxes(H) and latent heat fluxes(LE) were measured using the eddy covariance technique.The net radiation(Rn) was influenced by both solar altitude and synoptic weather changes.The yearly average intensity of Rn was 72.1 W/m~2,the minimum value of monthly average intensity was appeared in December and the maxim...