| In this paper,35ageneration Larix principis-rupprechtii plantation in Taiyue Mountain of Shanxi Province was used as the research object,in 2015 and 2016(May?September)two growing season,combined with field location monitoring and indoor experiment,the distribution of rains,litter water holding characteristics,Soil hydrological effects and surface runoff characteristics were studied.The results showed that:(1)During the observation period,a total of 54 rainfall events were monitored,the total precipitation was 1 223.11 mm,and the rainfall was concentrated in the period from June to August.Among them,33.33%,37.04%,20.37%,5.56%and 3.70%of the total number of rainstorms were light rain,rain,heavy rain,rainstorm and heavy rainstorm.With the increase of rainfall intensity,the stemflow,throughfall and canopy interception increased gradually,but the canopy interception rate decreased significantly.The canopy interception and the rainfall were significant power relations,and the throughfall and the stemflow were linear with the rainfall.?(2)With the increase of control intensity,the interception rate of forest canopy decreased gradually,showed an order in control(16.07%)>low thinning(14.29%)>moderate thinning(12.47%)>heavy thinning(10.94%);canopy interception in control,low thinning,moderate thinning and heavy thinning respectively of the total rainfall by 4.9%?4.0%?3.5%and 2.7%,throughfall respectively of the total rainfall by 79.03%,81.71%,84.03%and 86.36%.(3)The reserves of litter were higher than those of control,and with the increase of control intensity,the maximum water holding rate,maximum water holding capacity and effective water retaining content of litter were increasing,a certain intensity of the control measures are conducive to the increase in surface litter reserves and water holding capacity.The water holding capacity in half-decomposed litter layers was higher than that in un-decomposed litter layers,but the different density control had little effects on water holding process in un-decomposed litter layers.The water holding capacity under MT control was obviously higher than that under LT,HT and CK in half-decomposed litter layers;The absorption speed and immersion time had a power function.Half-decomposed litter layers had stronger water holding capacity than un-decomposed litter layers.There was no significant different on litter absorption speed rate among the different density control.(4)The effects of different intensity control measures on soil bulk density were not significant.The total soil porosities were 68.55%,68.81%,64.53%and 64.65%respectively control,low thinning,moderate thinning and heavy thinning.The maximum storage capacity of the soil in thinning and heavy thinning stand was lower than that in the control,low thinning.Soil surface(0?20 cm)in the initial permeation rate,moderate thinning stand were higher than other treatment points;The soil infiltration process can be well fitted with the Kostiakov empirical model.(5)During the observation period,the rainfall of the rainfall event with surface runoff is more than 5mm,and increases with the increase of rainfall.When the rainfall is the same,The greater the rainfall intensity,the greater the amount of surface runoff generated by rainfall events.The maximum surface runoff occurred in July,with an average of 53.59%of total runoff.With the increase of regulation intensity,the runoff of forest surface increased gradually,the surface runoff rates in control,low thinning,moderate thinning and heavy thinning were 1.69%,1.89%,1.95%and 2.34%. |
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