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【目的】分析不同演替阶段典型森林群落的凋落物量、组成特征及季节动态变化，为兴隆山森林生态系统碳贮量和养分循环研究提供科学依据。【方法】2012 年 8 月至 2015 年 7 月，采用凋落物收集器法，对甘肃兴隆山森林演替过程中的针阔混交林（山杨（Populusdavidiana）-白桦（Betulaplatyphylla）-青杄（Piceawilosonii）林）和暗针叶林（青杄-灌木林和青杄-箭竹（Fargesianitida）-苔藓林）演替阶段的 3 种典型森林群落凋落物量、组分、月动态进行了观测与研究。【结果】3 种典型森林群落年凋落量 5.534~7.951 t/hm2，山杨-白桦-青杄林＞青杄-灌木林＞青杄-箭竹-苔藓林，针阔混交林高于暗针叶林；凋落量随森林正向演替的进行而不断减少。山杨-白桦-青杄林以叶（44.91%）、杂物（20.53%）、枝（15.86%）、果（14.74%）为主，青杄-灌木林以叶（41.22%）、杂物（23.58%）、枝（18.53%）、果（13.32%）为主，青杄-箭竹-苔藓林以叶（37.48%）、杂物（27.51%）、枝（22.35%）为主；在叶凋落量中，针阔混交林以阔叶为主，暗针叶林则以针叶为主。3 种典型森林群落凋落量动态模式均为双峰型，但最高峰和最低峰出现时期有所不同；针阔混交林最高峰在 10 月，最低峰在 7 月；暗针叶林最高峰在 4-5 月，最低峰在 8-9 月。叶、针叶凋落量动态模式呈双峰型，高峰期在 4-5 月和 10 月；阔叶、杂物、枝、果和花凋落动态模式呈单峰型，阔叶最高峰在 10 月，杂物、枝和果在 4-5 月，花在 5-6 月；皮凋落动态无明显变化规律。【结论】森林演替对凋落量及其凋落物组成影响明显；随森林由阳性落叶阔叶林向阴性针叶林方向演替，森林年凋落量在逐渐变小；叶、阔叶凋落量所占比例逐渐减小，而针叶所占比例逐渐增加。
【Objective】 The objective of this study was to analyze litterfall, compositional characteristics and seasonal dynamics of typical forest communities in different succession stages and to provide a scientific basis for the study of carbon storage and nutrient cycling in the forest ecosystems of Xinglong Mountain. 【Method】 Populus davidiana - Betula platyphylla - Picea kingonii (Betula platyphylla) was used to study the forest succession process of Xinglong Mountain in Gansu from August 2012 to July 2015 by litter collection method. ) Forest and dark coniferous forest (Barley - Shrub and Barn - Fargesianitida - moss) were observed and studied on the litterfall, composition and monthly dynamics of three typical forest communities. 【Result】 The annual litterfall of three typical forest communities was 5.534 ~ 7.951 t / hm2, and that of aspen forest - Betula platyphylla forest> cattail forest - shrub forest> cattail plant - arrow bamboo - moss forest was higher than that of dark needles The litterfall decreased continuously with the forest forward succession. Aspen forest - Betula platyphylla forest is dominated by leaves (44.91%), debris (20.53%), branches (15.86%) and fruit (14.74% (23.58%), branch (18.53%) and fruit (13.32%), and the main species of leaves were leaf (37.48%), debris (27.51%) and branch In the amount of litterfall, broad-leaved coniferous and broad-leaved forest dominated, while dark coniferous forest dominated by needles. The dynamic patterns of litterfall in three typical forest communities were bimodal, but the peak and minimum peak appeared different. The highest peak of coniferous-broad-leaved mixed forest was in October and the lowest peak was in July. The highest peak of dark coniferous forest was in April-May, the lowest peak in August-September. The dynamic patterns of leaf and coniferous litterfall showed a bimodal pattern with peak periods in April to May and October. The dynamic patterns of leaf litter, debris, branches, fruit and flower litters showed a single peak pattern with the highest peak of broadleaf in October , Debris, branches and fruit in April to May, flowers in May to June; no significant change in the law of skin litter. 【Conclusion】 Forest succession had significant effects on the litterfall and its litter composition. With the succession of forest from the positive deciduous broad-leaved forest to the negative coniferous forest, the amount of annual forest litter decreased gradually. The leaf- The proportion gradually decreased, while the proportion of needles gradually increased.