三江平原毛果苔草湿地物理过程II──太阳辐射能在生态系统中的传输

The physical process II of Carex Lasiocarpa wetland in Sanjiang Plain- the transmission of sunshine radiation in ecosystem

毛果苔草湿地反射率平均为21.92%,全生长季反射太阳辐射能585.858MJ/m2.群落对太阳辐射的透射率平均为20.16%,在生长季节内透射太阳辐射能538.88MJ/m2.毛果苔草湿地群落的相对光照强度的分布与太阳高度角有关;而在累积叶面积指数(F)不变的情况下,消光系数(K)与相对照度的自然对数成正比;消光系数不仅受叶片透光率、倾斜角、方位角等的影响,而且与太阳高度角有关.毛果苔草湿地群落内太阳辐射能的季节性变化主要是受群落叶量的增减及其配置状况的影响,群落的叶面积集中分布层大约位于群落高的2/3处,其截获太阳辐射能的能力最强.

The average ratio of reflectivity of Carex lasiocarpa wetland is 21.92%, the total energy of reflect radiation in whole growing season in the wetland is 585.858MJ/m2. The average ratio of transmissivity of C. lasiocarpa community is 20.16%, the total energy of transmissivity radiation in whole growing season in the wetland is 538.88MJ/m2. The distribution of relativity illumination intensity of the wetland community is correlative to the sunshine height angle; in the changeless condition of leaf acreage index (F), coefficient of light extinction (K) is of direct proportion to the natural logarithm of relative illumination; in the same way, coefficient of light extinction (K) is not only effected by the light transmittance, angle of inclination and azimuth of leaf, but also relative to the sunshine height angle. The seasonal change of sunshine radiation in the wetland community is influenced mostly by the regulation of leaf quantity and its allocation state; the leaf acreage of the community is distributed concentratively about 2/3 of the community height, with its strongest ability to intercept and capture the sunshine radiation.