Xu Zi-Jun, Wan Xiao-Hua, Liang Yi-Fan, Shi Xiu-Zhen
School of Geographical Science, Fujian Normal University/Cultivation Base of State Key Laboratory of Humid Subtropical Mountain Ecology, Fuzhou 350007, China.
Ying Yong Sheng Tai Xue Bao. 2021 Jan;32(1):31-38. doi: 10.13287/j.1001-9332.202101.003.
The growth of roots towards aboveground litter layer is a common phenomenon in forest ecosystems. It is of great significance to examine the effects of root presence on litter decomposition for understanding nutrient cycling in forest ecosystems. We explored the effects of root growth on leaf litter decomposition, nutrient release and enzyme activities by establishing treatments with and without root with a one year field decomposition experiment in and forests at Sanming, Fujian. The results showed that after 360 days decomposition, leaf litter mass remaining ratio in the treatment with root was 8.4% and 19.7% lower than control, respectively. The presence of root exhibited significant effect on litter decomposition during the 90-180 days. Compared with the control, the remaining ratio of leaf litter carbon, nitrogen and phosphorus were 6.0%, 19.1% and 20.6% lower in the treatment with root in the forest, and were 21.3%, 23.2% and 20.5% lower in the forest, respectively. During the whole decomposition process, root presence did not affect the hydrolytic enzyme activity. After 180 days decomposition, the peroxidase activities in the treatment with root were 111.4% and 92.4% higher than control in the and forests, respectively. The remaining ratio of leaf litter carbon, nitrogen and phosphorus were negatively correlated with the activities of cellobiohydrolase, β-glucosidase, acid phosphatase, and peroxidase. Root presence in litter layer could accelerate litter decomposition and nutrient release through nutrient uptake and stimulation of oxidase activity.
根系向地上凋落物层生长是森林生态系统中的常见现象。研究根系对凋落物分解的影响对于理解森林生态系统中的养分循环具有重要意义。我们通过在福建三明的[具体森林名称1]和[具体森林名称2]森林中进行为期一年的田间分解实验，设置有根和无根处理，探讨了根系生长对凋落叶分解、养分释放和酶活性的影响。结果表明，分解360天后，有根处理的凋落叶质量残留率分别比对照低8.4%和19.7%。在90 - 180天期间，根系的存在对凋落物分解有显著影响。与对照相比，[具体森林名称1]森林中有根处理的凋落叶碳、氮和磷残留率分别低6.0%、19.1%和20.6%，[具体森林名称2]森林中分别低21.3%、23.2%和20.5%。在整个分解过程中，根系的存在不影响水解酶活性。分解180天后，[具体森林名称1]和[具体森林名称2]森林中有根处理的过氧化物酶活性分别比对照高111.4%和92.4%。凋落叶碳、氮和磷的残留率与纤维二糖水解酶、β - 葡萄糖苷酶、酸性磷酸酶和过氧化物酶的活性呈负相关。凋落物层中根系的存在可通过养分吸收和氧化酶活性的刺激加速凋落物分解和养分释放。
