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应用分解网袋法对亚热带常绿阔叶林7种常见林冠树种落叶分解过程中矿质元素(K,Na,Ca,Mg,Al,Fe,Mn,Cu和Zn)动态变化进行了为期2年的研究。这些树种是研究地区森林植被的代表种,且不同树种的落叶化学组成差异明显。研究结果表明:落叶分解速率(落叶干重残留百分率和分解常数k)与矿质元素初始浓度之间没有明显的相关性。但是,大多数情况下,落叶干重残留百分率与残留落叶的矿质元素浓度之间有着显著的相关关系。落叶分解过程中不同矿质元素的迁移性大小依次为:Na=K>Mg≥Ca>N≥Mn≥Zn≥P>Cu>>Al>>Fe。各树种的K和Na浓度在分解中均表现为下降趋势,Ca和Mg浓度亦表现为下降趋势,但在分解初期偶有升高倾向。而各树种中的其它元素(Zn,Cu,Al,Fe)浓度在分解中都表现出升高趋势,唯有Mn例外,在不同树种间,其浓度的变化模式存在一定差异。大多数树种的Cu,Al和Fe等3元素在分解试验末期的绝对重量均比初始重量显著提高,其机理在很大程度上可能归因于这些元素与腐殖质的结合,而不是生物固定。
The dynamic changes of mineral elements (K, Na, Ca, Mg, Al, Fe, Mn, Cu and Zn) during the deciduous decomposition of seven common canopy deciduous forests in the subtropical evergreen broad-leaved forest were studied by using the decomposition net bag method. the study. These species are the representative species of forest vegetation in the study area, and the differences of the chemical composition of leaves in different species are obvious. The results showed that there was no significant correlation between the rate of decollement decomposition (the percentage of residual dry leaf weight and the decomposition constant k) and the initial concentration of mineral elements. However, in most cases, there was a significant correlation between the percentage of residual dry leaf weight and the mineral element concentration of residual deciduous leaf. The order of the mobility of different mineral elements during decollement decomposition is: Na = K> Mg≥Ca> N≥Mn≥Zn≥P> Cu >> Al >> Fe. The K and Na concentrations of all species showed a downward trend in the decomposition, Ca and Mg concentrations also showed a downward trend, but occasionally increased in the early decomposition tendency. However, the concentrations of other elements (Zn, Cu, Al, Fe) in all species showed an increasing trend in the decomposition, with the exception of Mn, there was a certain difference in the concentration patterns between different species. The absolute weight of Cu, Al and Fe in most tree species at the end of the decomposition experiment were significantly higher than the initial weight. The mechanism of these elements may largely be attributed to the combination of these elements with humus, rather than biological fixation.