Effects of understory removal and litter addition on leaf and twig decomposition in a subtropical Chinese fir plantation
Effects of understory removal and litter addition on leaf and twig decomposition in a subtropical Chinese fir plantation
复制标题
亚热带杉木人工林林下去除和凋落物添加对叶和枝分解的影响
DOI：
10.1002/ldr.4086
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发表时间：
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影响因子：
4.7
通讯作者：
Mao Rong
中科院分区：
文献类型：
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作者：
Wan Songze;Fu Shenglei;Zhang Chenlu;Liu Juan;Zhang Yun;Mao Rong
由于全球变化和人类活动，亚热带人工林正在经历林下植被的清除和植物凋落物的增加。然而，如何林下清除和增加凋落物投入影响凋落物分解在这些人工林还不清楚。采用田间操作试验，研究了在中国南方亚热带杉木种植园中，林下植物清除和凋落物添加对凋落叶、枯枝落叶和混合枯枝落叶分解速率的影响。我们还研究了土壤化学性质和真菌和细菌磷脂脂肪酸（PLFA）后，林下植物去除和凋落物添加的变化。凋落物分解速率被抑制林下去除由于真菌PLFA的减少和相关的真菌细菌生物量的比例下降。凋落物的添加也延缓了凋落物的分解速率，尽管土壤NH 4 +-N浓度和真菌PLFA增加。然而，凋落物分解速率和土壤微生物PLFA保持不变，在林下植物去除和凋落物添加的存在下。在所有处理中，混合叶和嫩枝凋落物对凋落物分解速率产生加性效应。这些结果表明，林下植被清除和枯枝落叶添加相互作用影响枯枝落叶分解动态，并强调中国南方亚热带杉木人工林枯枝落叶混合物分解速率可以很容易地根据枯枝落叶组分进行预测。
Subtropical plantations have been undergoing understory removal and increased plant litter inputs due to global change and anthropogenic activities. However, how understory removal and increased litter inputs affect litter decomposition is still unclear in these plantations. Using a field manipulation experiment, we assessed the effects of understory removal and litter addition on decomposition rates of leaf litter, twig litter, and mixed leaf and twig litter over 16 months of incubation in a subtropical Chinese fir (Cunninghamia lanceolata) plantation in southern China. We also examined the changes in soil chemical properties and fungal and bacterial phospholipid fatty acids (PLFAs) after understory removal and litter addition. Litter decomposition rates were inhibited by understory removal due to the decreased fungal PLFAs and the associated declines in the ratio of fungal to bacterial biomass. Litter addition also retarded litter decomposition rates, despite the increases in soil NH4+‐N concentration and fungal PLFAs. However, both litter decomposition rates and soil microbial PLFAs remained unchanged in the presence of both understory removal and litter addition. In all treatments, mixed leaf and twig litter produced additive effects on litter decomposition rates. These results suggest that understory removal and litter addition interact to affect litter decomposition dynamics and highlight that litter mixture decomposition rates could be easily predicted from component litter in subtropical Chinese fir plantations of southern China.