白龙江上游5种典型灌木林枯落物蓄积量及持水特性

Litter Storage and Water Holding Capacity Characteristics of Five Typical Shrubberies in the Upper Reaches of Bailongjiang River of Gansu Province

采用野外实地观测与室内浸水法,对白龙江上游5种典型灌木林(荚蒾、甘肃柳、中华柳、箭竹、绣线菊)林地枯落物的蓄积量、持水量、持水率和吸水速率进行了研究。结果表明:5种典型灌木林林地枯落物蓄积量大小依次为箭竹林>甘肃柳林>荚蒾林>中华柳林>绣线菊林。5种灌丛类型枯落物半分解层的持水量均高于未分解层,中华柳未分解层持水量最高,箭竹半分解层持水量最高,绣线菊未分解层和半分解层持水量都是最小,整个枯落层最大持水量大小为中华柳>箭竹>荚蒾>甘肃柳>绣线菊;5种典型灌丛林不同分解程度枯落物的持水量与浸水时间存在对数关系,其吸水速率与浸水时间呈幂函数关系。

Shrubs are important components of forest in the upper reaches of Bailongjiang River.Previous studies on water holding characteristics in this region were focused more on the arbor forest,but less on shrubberies.By means of field survey and soaking extraction,five typical shrubberies（Viburnum dilatatum Thunb.,Salix fargesii Burk.,Salix cathayana Diels.,Fargesia spathacea Franch.,Spiraea schneideriana Rehd.）were selected for the present study.The results showed that litter storage in the five typical shrubberies followed the order of F.spathacea〉S.fargesii〉V.dilatatum〉S.cathayana〉S.schneideriana.The half-decomposed litters had a larger water holding capacity than un-decomposed litters in the five typical shrubberies.The water holding capacity of S.cathayana un-decomposed litters was the highest among different shrubberies,the half-decomposed litters of F.spathacea was the highest among different shrubberies,the un-decomposed and half-decomposed litter layers of S.schneideriana were both the lowest among different shrubberies.The maximum water holding capacity of the whole litter layer was in the order of S.cathayana〉F.spathacea〉V.dilatatum〉S.fargesii〉S.schneideriana.Water holding capacity of the litters of different decomposition degree changed logarithmically with soaking time,and the water absorption rate followed a power function.