Hydrological effects of forest litters and soil in different types of understory vegetation in aerially-seeded Pinus massoniana plantation
[Background] Understory vegetation is an important part of forest ecosystem.It can greatly affect the quality and amount of forest litter and the physical and chemical properties of soil,and further affect the water storage capacity of litter layer and soil layer.Thus,the influence of understory vegetation on the function of water conservation of forest ecosystem cannot be ignored.[Methods] We set 12 typical plots with area of 20m × 20m of each,in which the dominant types of understory vegetation were dicranopteris,graminoid,and shrub respectively in aerially-seeded Pinus massoniana plantation,and collected the data of field investigation and sample determination.Then we analyzed and compared the water-holding capacities of litter and storage capacities of soil in the 3 types.[Results] Total amount of existing litter in three types were about 0.65 t/hm2-3.57 t/hm2,it in shrub type was significantly higher than that in the dicranopteris type and the graminoid type,and it in the dicranopteris type was significantly higher than that in the graminoid type.The natural water content rate,maximum water-holding rate,maximum interception rate,and effective interception rate of litters in three types ranged as 15.50％-29.74％,167.70％-218.25％,139.00％-199.66％ and 113.85％-167.39％,respectively.The natural water-holding capacity,maximum water-holding capacity,maximum interception capacity,and effective interception capacity of litters in three types presented as shrub type ＞dicranopteris type ＞ graminoid type.The indexes of litter water-holding capacity,excluding the natural wate capacity of semi-decomposed layer,in shrub type were significantly higher than those in the other two types.For the hydrological effects of soil,the soil maximum water storage,non-capillary water-holding capacity,and capillary water-holding capacity of 0-20 cm soil depth in the dicranopteris type were the highest among the three types with the capacity of 865.95 t/hm2,138.96 t/hm2,and 726.99 t/hm2,respectively.The results of variance analysis demonstrated that the total non-capillary water-holding capacity of 0-20 cm soil depth in dicranopteris type was significantly higher than those in the other two types,while the soil maximum water storage capacity of 0-10 cm soil depth in dicranopteris type was significantly higher than that in the graminoid type.And as to the rest of indicators,there was no significant difference among the three types.[Conclusions] Comprehensive analysis revealed that the hydrological effects of litter in the shrub type were significantly higher than that in dicranopteris type and the graminoid type,while the hydrological effects of soil in the dicranopteris type were better than those in the shrub type and the graminoid type,due to the soil maximum and effective water storage accounted for over 99％ and 94％ of the woodland surface (litter layer plus soil depth of 0-20 cm),respectively.Conclusively,the hydrological effects of woodland surface in the dicranopteris type,on the whole,was better than those in the shrub type and the graminoid type.
国家科技期刊平台
NSTL
万方数据
维普
