【摘要】 [目的]基于华北石质山区侧柏人工林2014年(3—10月)降水数据进行量化分析,探究其降水的再分配规律。[方法]采用野外定位研究方法,对不同结构(郁闭度、枝下高)侧柏人工林林冠层降水再分配特征进行分析。[结果](1)1/2枝下高0.4、0.6、0.8郁闭度林内穿透雨总量分别为181.1、168.1、147.1 mm,穿透雨率分别为78.8%、73.1%、64.0%;树干径流总量分别为6.0、5.9、3.9 mm;总树干径流率分别为4.2%、2.6%、1.7%;林冠截留总量分别为39.5、56.1、79.1 mm;林冠截留率分别为17.2%、24.4%、34.4%。(2)1/3枝下高0.4、0.6、0.8郁闭度林内穿透雨总量分别为175.6、154.8、136.0 mm,穿透雨率分别为76.4%、67.3%和59.2%,树干径流总量分别为8.3、4.9、3.3 mm,总树干径流率分别为3.6%、2.1%和1.4%,林冠截留总量分别为46.3、70.4、90.7 mm,林冠截留率分别为20.1%、30.6%和39.5%。[结论](1)侧柏人工林同一枝下高不同郁闭度林分林内穿透雨量差异不显著。2种枝下高郁闭度为0.4和0.8之间的树干径流量均存在显著差异,郁闭度0.4和0.6以及0.6和0.8之间差异不显著。(2)郁闭度为0.4、0.6、0.8时,冠厚占树高2/3(即枝下高为1/3)的林分林冠截留量分别是1/2的1.17、1.25和1.14倍。(3)2种枝下高各自不同郁闭度间林冠截留量均存在显著差异。(4)同等降雨量情况下雨强越大,林冠截留量越小;2次降雨间隔时间越长,林冠层越干燥,林冠截留能力越强;枝下高越低(即冠层厚度越大),林冠截留量越大,且随着郁闭度的增加,林冠截留量逐渐增大。更多还原

【Abstract】 [Objective]Based on the precipitation data of 2014 toanalyze quantitatively the law of redistribution of precipitationin mountainous area of North China. [Method]The method of field positioning was used to analyze the rainfall redistribution of Platycladusorientalis plantation with different structure( canopy,under branch height) characteristics. [Result]( 1) At the height of 1 /2 under branch height,the through rainfalls of stands with canopy density of 0. 4,0. 6,0. 8 respectively were 181. 1,168. 1,and 147. 1 mm,the rates of through rainfall were 78. 8%,73. 1%,and 64. 0%; The total stemflowswere 6. 0,5. 9 and 3. 9 mm respectively,the rates of stemflowwere4. 2%,2. 6% and 1. 7%. The total canopy interceptionswere respectively 39. 5,56. 1 and 79. 1 mm. The rates of canopy interception were 17. 1%,24. 4% and 34. 4%.( 2) At the height of 1 /3 under branch height,the through rainfall of stands with canopy density of 0. 4,0. 6,0. 8 canopy were 175. 6 mm,154. 8 mm,and 136. 0 mm,therates of through rainfall were 76. 4%,67. 3%,and 59. 2%. The total stemflowswere respectively 8. 3,4. 9 and 3. 3mm,the rates of stemflowwere 3. 6%,2. 1% and 1. 4%. The total canopy interceptionswere respectively 46. 2,70. 4 and 90. 6 mm. The rates of canopy interception were 20. 1%,30. 6% and 39. 4%. [Conclusion]( 1) At the same under branch height,the difference in through rainfall of P. orientalisplantation with different canopy coverage was not significant. The stemflow between the stands with canopy density of 0. 4 and 0. 8 showed significant difference,while the difference between the canopy density of 0. 4 and 0. 6 and between the canopy density of 0. 6 and0. 8 were not significant.( 2) At the stand with the density of 0. 4,0. 6,and 0. 8,the canopy interception of the stand with crown thickness accounts for 2 /3 the tree height were 1. 17,1. 25 and 1. 14 times that of the stand with crown thickness accounts for 1 /2 the tree height.( 3) Significant differences in crown interception were found among different canopy density.( 4) At the same rainfall intensity,the more the rainfall,the smaller the canopy interception; the longer the interval of rainfall time,the drier the canopy drier and the stronger the interception ability; The lower the branch height,the larger the canopy interception amount and with the increase of the canopy density,the canopy interception increased.更多还原