Experimental Decomposition of Litter from the Tamaulipan Cloud Forest: A Comparison of Four Simple Models
Experimental Decomposition of Litter from the Tamaulipan Cloud Forest: A Comparison of Four Simple Models
复制标题
塔毛利潘云雾森林凋落物的实验分解：四种简单模型的比较
DOI：
10.2307/2388624
复制
发表时间：
1987
期刊：
影响因子：
2.1
通讯作者：
J. Becerra
中科院分区：
文献类型：
--
作者：
E. Ezcurra;J. Becerra
基于不同的分解速率行为假设，提出了四种不同的微分方程分解模型。：模型1，速率常数；模型2，速率随剩余凋落物分数线性下降；模型3，速率随剩余凋落物分数非线性递减；模型4，凋落物由两个组分组成，每个组分的分解速率都是恒定的，但随时间的比例而变化（因此总体速率也会随时间而变化）。利用塔毛利潘云林三种不同凋落物类型的干重数据对模型进行了测试，这三种凋落物类型分别是：枫叶、李果实和枫枝。三种类型均在垃圾袋中恒温(30？C)和100%的相对湿度。收集四个重复的亚组，干称重，并在三个月的时间间隔增加后丢弃。模型1（负指数）始终给出数据的最差拟合。模型3和模型4的拟合效果最佳，表明凋落物具有较高的内在异质性，因此也具有相对分解速率的变异性。
Four differential equation decomposition models were postulated, based on different assumptions of the behavior of the decomposition rate (. : Model 1, rate constant; Model 2, rate decreasing linearly as a function of the remaining litter fraction; Model 3, rate decreasing nonlinearly as a function of the remaining litter fraction; and Model 4, litter formed by two fractions, each having a constant decomposition rate but varying in proportion with time (thus the overall rate will also vary with time). The models were tested against dry-weight data from three contrasting litter types from the Tamaulipan cloud forest: leaves of Liquidambar styraciflua, fruits of Prunus serotina, and branch segments of L. styraciflua. Al three types were incubated in litter bags at constant temperature (30?C) and 100 percent relative humidity. Subsets of four replicates were collected, dry-weighed, and discarded at increasing intervals for three months. Model 1 (the negative exponential) consistently gave the worst fit to the data. The best fits were obtained from Models 3 and 4, showing the high intrinsic heterogeneity of litter and, consequently, the variability of the relative decomposition rates.