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【目的】分析不同演替阶段典型森林群落凋落物的量、组成特征及月动态,了解兴隆山森林生态系统碳贮量和养分循环状况。【方法】采用凋落物收集器法,对甘肃兴隆山森林演替阶段的3种典型森林群落针阔混交林(山杨(Populus davidiana)-白桦(Betula platyphylla)-青杄(Picea wilosonii)林)和暗针叶林(青杄-灌木林和青杄-箭竹(Fargesia nitida)-苔藓林)的凋落物量、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物量5 534.48~7 951.25 kg/hm~2,大小排序为: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-青杄林中以叶(44.91%)、杂物(20.53%)、枝(15.86%)、果(14.74%)为主,青杄-灌木林中以叶(41.22%)、杂物(23.58%)、枝(18.53%)、果(13.32%)为主,青杄-箭竹-苔藓林中以叶(37.48%)、杂物(27.51%)、枝(22.35%)为主;在叶凋落物中,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。针叶凋落量动态模式呈双峰型,高峰期出现在4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;树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,森林年凋落量逐渐变小;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 the quantity, compositional characteristics and monthly dynamics of litter in typical forest communities in different successional stages and to understand the carbon storage and nutrient cycling in the forest ecosystems of Xinglong Mountain. 【Method】 Populus davidiana-Betula platyphylla-Picea wilosonii forest was used to analyze the forest succession stages of Xinglong Mountain in Gansu Province. And dark coniferous forest (barley - shrub and Fargesia nitida - moss) were observed and studied. 【Result】 The results showed that the annual litterfall of the three typical forest communities was 5 534.48 ~ 7 951.25 kg / hm 2, and the order of size was as follows: Populus alba - Betula platyphylla forest. The broad-leaved mixed forest was higher than that of dark coniferous forest. The litterfall decreased with the success of forest forward succession. The results showed that leaves (44.91%), debris (20.53%), branches (15.86%) and fruit (14.74%) were the dominant species in Populus alba - Betula platyphylla forest with leaves (41.22% (23.58%), branch (18.53%) and fruit (13.32%) were the main species. Leaf (37.48%), debris (27.51%) and branch In leaf litter, broad-leaved coniferous and broad-leaved mixed forests dominated the dark coniferous forest with needle-based. 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 coniferous litterfall showed a bimodal pattern, with the peak appeared in April and October; the dynamic pattern of broadleaf, debris, branches, fruit and flower litter showed a single peak, the highest peak of broadleaf in October, debris , Branch and fruit in April-May, spent in May-June; no significant changes in the dynamics of bark litter. 【Conclusion】 Forest succession had significant effects on litterfall and its litter composition. With the succession of forest from the positive deciduous broad-leaved forest to the negative coniferous forest, the annual litterfall became smaller and the proportion of broad- Decrease, while the proportion of needles gradually increased.