【摘要】 林区公路的生态水文影响历来少受关注,道路对集水区径流的影响及其机制仍不明确。在南岭国家森林公园选取2个对比森林集水区,其一为自然状态（W1）,另一个受旅游公路干扰（W2）,利用各集水区2017年8月-2018年7月连续监测的降雨和流量数据,研究了林区公路对径流的影响。结果表明:（1）在W2集水区,不同雨量级的次降雨产生的快速径流量是集水区W1的1.64-3.69倍,W2的水文响应值的年平均值（12.60%）是W1（4.32%）的2.92倍;而且在相似降水条件下W2的洪峰流量远大于W1,洪峰滞后雨峰的时间比W1短;（2）基于79场（W1）和87场（W2）雨量P≥5 mm的次降雨及其径流的监测,将两集水区各次降雨过程中产生的快速径流（QF）与降雨量（P）、降雨历时（PD）、前7天降水量（AP7）、最大30 min雨强(I₃₀)、最大60 min雨强(I₆₀)、平均降雨强度（AHRD）和初始流量（F_i）各指标进行相关分析,两个集水区的快速径流都与降雨量、降雨历时呈极显著相关;此外W1的快速径流与I₆₀呈极显著相关,与I₃₀显著相关,W2的快速径流与I₃₀和I₆₀相关关系不显著,但与AP7呈显著相关;（3）观测期间,W2的年径流系数为0.489 5,W1的年径流系数为0.443 7,基流占总径流的比率（BF/R）在一年中每个月都表现为W2小于W1。林区公路修建引起了径流量、径流组分分配以及径流过程变化:林区公路明显增加集水区的快速径流量和洪峰流量并使洪峰滞后雨峰的时间缩短,导致产生快速径流的主导因素改变;显著减少了集水区的基流补给,使集水区径流中基流比例显著减少。更多还原

【Abstract】 Less attention has always been given to the ecohydrological effects of forest road,and the influnces of road on catchment runoff and its mechanisms remain unclear.In this study,a paired catchments in Nanling National Forest Park,one was a natural catchment（Laopengding,W1）,and the other（Xingonglu,W2）had been disturbed by tourist roads,were selected to monitor rainfall and to gauge streamflow.The continuous monitoring data of rainfall and runoff from both catchments during Auguest of 2017 to July of 2018 were used for analysing influences of forest roads on runoff.The results showed that:（1）the quickflow（QF）produced by individual rain events at different rainfall levels in W2 was 1.64 to 3.69 times than that in W1,the annual average hydrological response value（ratio of QF to rainfall,HR）in W2 accounted for 12.60%and was 2.92 times than that in W1（4.32%）.The peak flow from W2 was much larger than that from W1,and there existed a shorter lagging time of flood peak lagging rain peak in W2 under the same（similar）precipitation conditions.（2）Based on the monitoring data of the rainfall-runoff process of 79 rain events in W1 and 87 rain events in W2 which rainfall was more than 5 mm,the correlations between QF and precipitation（P）,precipitation duration（PD）,antecedent precipitation for 7 days prior to storm（AP7）,maximum 30-minute rainfall intensity(I₃₀),maximum 60-minute rainfall intensity(I₆₀),average hourly rainfall density（AHRD）and initial flow（Fi）were analyzed in each individual rain events.QF in both catchments was significantly correlated with P and PD.In addition,QF in W1 was significantly correlated with I₆₀and I₃₀,while QF in W2 had no significant correlation with I₃₀ and I₆₀,but was significantly correlated with AP7.And（3）during the observation period,the annual runoff coefficient of W2 was 0.489 5,the annual runoff coefficient of W1 was 0.443 7,and the ratio of baseflow to total runoff（BF/R）was W2 less than W1 every month of the year.The construction of forest roads caused runoff,runoff component distribution and runoff process changes:forest roads significantly increased the QF and flood peak flow in W2 and shortened the lagging time between flood peak and rain peak,changed the dominant factors of fast runoff,significantly reduced the baseflow recharge in W2,and significantly reduced the baseflow proportion of runoff in W2.更多还原