藏东南高山松林凋落物特征研究1

Objective:To explore the characteristics of litters in alpine forest in southeast Tibet,and to provide theoretical basis for revealing the formation reasons of the characteristics of litters in this area and playing the role of ecological security barrier of Qinghai-Tibet Plateau.METHODS:Taking alpine pine forest,the dominant population of coniferous forest in southeast Tibet as the research object,5 typical sample points were selected in southeast Tibet to measure the change of characteristics of litters.Results:The average thickness of alpine pine litter at five sample sites was 10.98±1.01cm.The order of different layers of litter thickness at LL,BK,DZ and BB samples was as follows:undecomposed layer>semi-decomposed layer>decomposed layer,while that at DD sample sites was the opposite.The average fresh weight of litters in the five samples was 7075.73±938.51g.In general,the order of fresh weight of litters in different layers was as follows:decomposed layer>semi-decomposed layer>undecomposed layer;The total water content of the five samples was in the order of semi-decomposed layer(64.00±6.12%)>rotten layer(52.65±5.08%)and undecomposed>layer(50.81±4.88%).The order of litter percentage of each group in alpine forest was:leaf BBB 0 fruit BBB 1 branch BBB 2 other.Conclusion:The litters of alpine pine forest in southeast Tibet are mainly characterized by thick litters,large inventory,relatively low moisture content and large percentage of needles.Its characteristics are similar to those of domestic coniferous forest litter,but different from those of global forest litter.