滇中华山松人工林的水文特征及水量平衡

Hydrological Properties and Water Balance of Pinus armandii Plantation in Central Dian Plateau, Yunnan Province

根据滇中高原的华山松林集水区径流场连续 3a的降雨和径流观测数据 ,进行了华山松人工林的水文特征及水量平衡的研究。结果表明 :( 1)本区域降水量的季节分配不均 ,湿季 ( 6～ 10月 )降水量占全年的 80 % ,降水量主要由大于 10mm以上的降雨带来 ,且降雨强度大部分小于 5.0mm·h- 1。 ( 2 )集水区年平均降雨量 10 0 5.6mm ,在林冠作用面降雨量的分配中 ,林冠截留雨量 2 10 .6mm ,截留率 2 0 .9% ;穿透过林冠层的降雨 74 5.3mm ,树干茎流量 4 9.7mm ,分别占降雨量的 74 .2 %和 4 .9%。 ( 3)集水区径流的月变化滞后于降雨 ,总径流量 172 .2 9mm ,总径流系数 17.13% ,其中 ,地表径流 8.0 3mm ,地下径流 164.2 6mm ;地表径流主要集中在雨季产生 ,一次性降雨对地表径流的影响显著 (R =0 .91)。 ( 4 )土壤蓄水年变化量 11.2mm ,约占年降水量的 1.1% ,但月变化较大 ;系统水量最大的输出是蒸散 ,每年以气态形式返回大气的水量 82 2 .1mm ,占降水量的 81.8% ;在蒸散的水量中 ,林冠截留雨量的直接物理蒸发量 2 10 .6mm ,占总蒸散量的 2 5.6%。

According to the 3 years' observation on the precipitation and runoff in Pinus armandii forest watershed runoff observation station in Central Dian Plateau, the study on hydrological properties and water balance of plantation was conducted, and some analysis results are as follows: (1) The seasonal distribution precipitation in this area is uneven, the rainfall of wet season (from Jun. to Oct.) accounts for 80% of the yearly total, the precipitation is mainly brought by rainfall that is more than 10 mm, and most of the rain intensities are less than 5.0 mm·h -1 . (2) The annual precipitation of the watershed is 1 005.6 mm. Regarding to the precipitation distribution of crown acting surface, crown interception is 210.6 mm, and the ratio is 20.9%; the through fall precipitation is 745.3 mm ,stemflow precipitation is 49.7 mm, and account for 74.2% and 4.9%, respectively. (3) Monthly change lags behind the precipitation, and the total runoff is 172.29 mm, total runoff coefficient is 17.13%, in which the surface runoff is 8.03 mm, the underground runoff is 164.26 mm; the surface runoff mainly centralizes in wet season, and one off rainfall obviously affects surface runoff (R=0.91). (4) Annual soil moisture variation is 11.2 mm, accounting for 1.1% of the total annual precipitation. But the monthly change is relatively large; the evapotranspiration is the biggest output of the system water flow, 822.1 mm water returns to the air in the form of gas phase, accounting for 81.8% of the total precipitation; among the evapotranspiration water, the direct physical evaporation capacity of crown interception is 210.6 mm, accounting for 25.6% of the total evapotranspiration.