马尾松人工纯林凋落松针数量及基质质量动态

发布时间：2018-03-12 22:47

本文选题：马尾松　切入点：林分密度　出处：《生态学报》2017年22期 　论文类型：期刊论文

【摘要】：凋落物是森林生态系统的重要组成部分,其产量与基质质量是影响植物-土壤间养分循环的重要因素。以3种密度马尾松人工纯林为研究对象,分析松针凋落模式及基质质量变化规律,比较不同林分密度间松针凋落特性差异,探讨松针基质质量、产量及气候因素间的关系。结果表明:松针凋落数量动态变化属双峰型,在2月呈现一个小高峰,在10/11月达最高峰。3种密度林分中各月凋落松针的N、P浓度均差异显著(P0.05),全年最高值出现在4—6月,8—12月的松针N、P浓度显著低于其他时段;不同月份凋落松针木质素浓度也差异显著(P0.05),在2月木质素含量达峰值,7、8月含量较低;3种密度林分中各月凋落松针的C/N、C/P、L/N和L/P比存在显著差异(P0.05),4—6月呈现最低值,9/11/12月则出现最高值,相差达2—3倍,且均高于养分释放临界值,不利于松针N素和P素的释放。林分密度对松针凋落数量和N浓度影响显著(P0.05),中等密度林分松针凋落数量高于低、高密度林分,中、高密度林分凋落松针N浓度显著高于低密度林分。凋落松针基质质量与自身凋落数量密切相关,并且受气温和降水量的影响。凋落松针N、P浓度与凋落数量呈显著负相关(P0.05),C/N、C/P、L/N、L/P比与凋落数量呈显著正相关(P0.05),说明更多凋落物产量将伴随着更低的基质质量,将有更慢的分解速度。
[Abstract]:Litter is an important part of forest ecosystem, and its yield and substrate quality are important factors affecting nutrient cycling between plant-soil. The variation of pine needle litter pattern and substrate quality was analyzed, the characteristics of pine needle litter were compared among different stand densities, and the relationships among substrate quality, yield and climatic factors were discussed. The results showed that the dynamic change of pine needle litter number was a bimodal type. In February, there was a small peak, in 10/11 months reached the highest peak of 3 kinds of density stands, in each month there were significant differences in the concentration of N P of pine needles, the highest value of the whole year appeared in April to June, August to December, the concentration of N P in pine needles was significantly lower than that in other periods. The lignin concentration of pine needles also showed significant difference in different months. The lignin content reached a peak value in February and reached a peak value in February. In August, there was a significant difference in the C / N / P / N and L / P ratios of C / N / P / N and L / P in the three density stands with lower densities. The lowest value was found in April to June, and the highest value appeared in 9 / 11 / 12 months. The difference was 2-3 times, and higher than the critical value of nutrient release, which was not conducive to the release of N and P in pine needles. Stand density had a significant effect on the number and concentration of pine needles (P0.05N), and the number of pine needles litter in medium density stands was higher than that in low, high-density stands. The N concentration of pine needles in high density stands was significantly higher than that in low density stands. Under the influence of air and precipitation, there was a significant negative correlation between the concentration of N ~ (+) P and the number of litters. There was a significant positive correlation between the ratio of P ~ (0.05) C / P ~ (1 / P) and the number of litters, which indicated that more litter yield would be accompanied by lower substrate quality and slower decomposition rate.
【作者单位】：贵州大学贵州省森林资源与环境研究中心;贵州师范大学地理与环境科学学院;贵州大学林学院;
【基金】：国家科技支撑项目(2015BAD09B0102) 贵州省科技重大专项(黔科合重大专项字[2012]6001号) 贵州省林业重大专项(黔林科合[2010]重大03号) 国家自然科学基金项目(41261058)
【分类号】：S714

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