辽西低山丘陵区针叶林与阔叶林枯落物持水性对比

为对比分析辽西低山丘陵区针叶林与阔叶林枯落物的持水性差异,为辽西森林植被恢复提供科学依据和技术支撑,选取3个针叶林(红松林、油松林、兴安落叶松林)和3个阔叶林(榆树林、山杨林、紫椴林)下的枯落物作为研究对象,采用野外现场采样与室内浸水相结合的方法对枯落物的持水特性进行测定.结果表明:针叶林平均蓄积量大于阔叶林,其中针叶林蓄积量在14.65 ～ 17.75 t/hm2,阔叶林在8.44 ～ 16.92 t/hm2;针叶林枯落物平均厚度(2.79 cm)大于阔叶林(2.44 cm);针叶林最大持水率在148.88％ ～ 173.19％,阔叶林在145.42％ ～156.91％;针叶林有效拦蓄水量为19.47～25.59 t/hm2,阔叶林有效拦蓄水量为10.56～ 22.04 t/hm2,表现为针叶林下枯落物的拦蓄能力更强;针叶林半分解层拦蓄水量显著大于未分解层,阔叶林未分解层拦蓄水量大于半分解层;阔叶林未分解层吸水速率大于针叶林.

Comparison of litter water-holding capacity between coniferous and broadleaf forests in low mountainous and hilly areas of western Liaoning

Background] Domestic and foreign scholars have conducted a lot of researches on the litter hydrological characteristics of different forest types in different regions,mathematical model of litter storage,mathematical model of litter interception and its mechanism.However,it is lack of study on the hydrological characteristics of typical forests' litters in western Liaoning area of China and the differences of hydrological characteristics of litter in different leaf shapes,to compare and analyze the water-holding capacity of litter of coniferous forest and of broadleaf forest in low-mountainous and hilly areas of western Liaoning,and provide the scientific basis and technical support for forest vegetation restoration,Methods] Three coniferous forests (Pinus koraiensis forest,Pinus tabulaeformis forest and Larix gmelini forest) and three broadleaf forests (Ulmus pumila forest,Populus davidiana forest and Tilia amurensis forest) were selected as the study objects,and took 3 samples along a single diagonal line of every forest's sample plot.Maximum water-holding rate,maximum water-holding capacity,accumulated water-holding capacity,and water absorption rate were measured by indoor water immersion and related calculation.Results] The average storage volume of coniferous forests was larger than that of broadleaf forests,and the storage volume of coniferous forests was between 14.65 t/hm2 and 17.75 t/hm2,while that of broadleaf forests was in the range of 8.44-16.92 t/hm2.The average thickness of litter in coniferous forests (2.79 cm) was larger than that in broadleaf forests (2.44 cm).The maximum water-holding capacity of coniferous forests was 148.88％-173.19％,while that of broadleaf forests was 145.42％-156.91％.The modified interception volume of coniferous forests was 19.47-25.59 t/hm2,and that of broadleaf forests was 10.56-22.04 t/hm2.The water absorption rate of coniferous forests was (410.92-498.74 g/(kg·h)),while that of broadleaf forests was (449.32-508.25 g/(kg·h)).Conclusions] There are differences between litter storage volume and thickness of coniferous and broadleaf forests.Water-holding capacity differentiation characteristics of coniferous forests and broadleaf forests are related to the proportion of litter decomposition layers.The ability of interception of coniferous forests is stronger than broadleaf forests.The interception volumes of semi-decomposed layer of coniferous forests are significantly larger than those of undecomposed layer,while the interception volumes of undecomposed layers of broadleaf forests are greater than that of semi-decomposed layer.The water absorption rate of undecomposed layer of coniferous forest is faster than that of semi-decomposed layer,and the semidecomposing layer of broadleaf forest is faster than that of undecomposed layer.The water absorption rate of semi-decomposed layer decreased sharply in 0-4 h,especially in broadleaf forest.