山西灵空山油松天然次生林不同群落凋落物动态特征研究

摘要

To elucidate the litter yield,composition and the seasonal dynamics of Pinus tabulaeformis natural secondary forest litters,and to study the rhythm of leaf and flower fruiting of the dominant species in the two community types,taking the forest dynamic monitoring plots of Pinus tabulaeformis-Quercus wutaishanica mixed forest (4 hm2) and Pinus tabulaeformis forest (1 hm2) in Lingkong Mountain of Shanxi as the research platform,twenty-four and eleven litter collectors were set up in the plots,and the litterfall data collected from November 2014 to November 2015 were analyzed.The result showed that 4 hm2 and 1 hm2 plots were collected litter 12.79,6.427 kg,respectively,and the average litterfall was 12 446.476,12 032.05 kg/(hm2·a),respectively.The annual litterfall of each component was ranked as follows:the Pinus tabulaeformis forest were leaf (67.51％),flower (12.15％),branch (9.58％),debris (9.05％),fruit (1.71％),the mixed forests were leaves (58.21％),debris (16.28％),fruit (11.94％),branches (9.23％) and flowers (4.34％).The monthly dynamic changes of litter on the two community types of the Pinus tabulaeformis forest in Lingkong Mountain were identical,all of which showed obvious unimodal patterns.The total litterfall litter peak of Pinus tabulaeformis and mixed forest appeared in mid-October,the minimum appeared in mid-July.The amount of leaf litter and the total amount of litter basically remained the same,and the maximum litterfall amount of flower was respectively appeared in mid-October and mid-September.The litterfall of the two communities was 8 122.502,7 245.256 kg/hm2,respectively,of which the litterfall was 87.7％ and 37.7％,respectively,and the litterfall of deciduous tree species accounted for 1.3％ and 44.3％,respectively.The leaf litter rhythm of evergreen species and deciduous tree was significantly different.The correlation coefficient between the important value of the main dominant species in Pinus tabulaeformis and its deciduous natural secondary forest was 0.949 and 0.800,respectively.The results indicated that the litterfall of Pinus tabulaeformis communities was not significantly different from that of the other communities.The monthly dynamics of the Pinus tabulaeformis forest showed a single peak,and the litter size of the Pinus tobulaeformis forest could vary from year to year.There was no significant correlation between the important values of the main dominant species and the amount of fallen leaves.%为阐明油松天然次生林凋落物的产量、组成及其月动态,并探讨2个群落类型内主要优势物种的叶和花果的凋落节律,以山西灵空山油松-辽东栎混交林(4 hm2)和油松纯林(1 hm2)森林动态监测样地为研究平台,在样地内各设置24,11个凋落物收集器,对2014年10月至2015年11月收集的凋落物数据进行分析.结果表明,松栎混交林和油松纯林样地分别收集到凋落物12.79,6.427 kg,平均凋落量分别为12 446.476,12 032.05 kg/(hm2·a).按组分年凋落量由大到小进行排序,油松纯林为叶(67.51％)＞花(12.15％)＞枝(9.58％)＞杂物(9.05％)＞果实(1.71％);松栎混交林为叶(58.21％)＞杂物(16.28％)＞果实(11.94％)＞枝(9.23％)＞花(4.34％).灵空山油松天然次生林2个群落类型落叶量月动态变化一致,均呈明显的单峰型;年凋落物量的凋落高峰期均出现在10月中旬,最小值出现在7月中旬;花果最大月凋落量分别出现在10月中旬和9月中旬.2种群落一年中叶凋落量分别为8 122.502,7 245.256 kg/hm2,其中,油松叶凋落量分别占叶凋落量的87.7％和37.7％,群落内其他落叶阔叶物种叶凋落量分别占叶凋落量的1.3％和44.3％.由此可见,常绿针叶树种和落叶阔叶树种的叶凋落节律呈明显不同步状态.油松天然次生林内主要优势物种的重要值与落叶量之间的相关系数分别为0.949和0.800.研究表明,油松不同群落凋落量差异不大,月动态均呈单峰型,油松叶凋落量可能存在大小年现象,2种群落主要优势物种的重要值与落叶量之间并无明显相关关系.