Chen Zhangting, Arif Muhammad, Tian Mengyao
School of Tourism Ecology and Environment, Guilin Tourism University, Guilin, China.
Guangxi Cultural Tourism and Wellness Integrated Development Center, Guilin Tourism University, Guilin, China.
Front Plant Sci. 2025 Jun 4;16:1543011. doi: 10.3389/fpls.2025.1543011. eCollection 2025.
Karst river systems (KRSs) are essential to regional biogeochemical cycling and are defined by their distinct geomorphological and hydrological features. Understanding the factors controlling litter decomposition and associated nutrient fluxes within these systems is essential for predicting ecosystem responses to environmental changes. While extensive research is underway on litter decomposition and nutrient dynamics, studies on the interactions between species richness and elevation across seasons in KRSs remain limited. This study investigates the effects of elevation (800 m, 110 m, and 60 m) and seasonality (spring and autumn) on foliage decomposition and associated nutrient fluxes in KRSs along the Li River in China. We examined the foliage decomposition of three species: (Linn.) Rich., Brongn., and Koidz. It included seven litter treatments in single-species and mixed-species litter bags (3 species in all single-, 2- and 3-species combinations). A total of 336 decomposition bags were used to measure leaf mass loss and nutrient release during two six-month periods at three elevations in the study area in 2023. Results revealed that seasonal changes significantly influenced initial leaf elemental concentrations, with spring samples showing the most pronounced effects. Elevation had more effect on mass loss than litter treatments, with distinct nutrient release patterns observed across different elevations. Among single species, exhibited the highest mass loss and nutrient release at lower elevations during spring, while showed the lowest rates in autumn at high elevations. Mixed-species treatments displayed different decomposition patterns, with mass loss and nutrient release following the sequence: . Nutrient release in mixed species showed significant interactions with elevation and season, displaying both positive and negative non-additive effects. Correlation analysis indicated stronger relationships between nutrient release and mass loss in than in and . This study underscores the intricate interactions between biotic and abiotic factors in KRSs. It highlights the importance of considering elevation and seasonal dynamics in ecological restoration efforts in KRSs.
岩溶河流系统（KRSs）对区域生物地球化学循环至关重要，其由独特的地貌和水文特征所界定。了解控制这些系统内凋落物分解及相关养分通量的因素，对于预测生态系统对环境变化的响应至关重要。虽然目前正在对凋落物分解和养分动态进行广泛研究，但关于岩溶河流系统中物种丰富度与海拔在不同季节间相互作用的研究仍然有限。本研究调查了海拔（800米、110米和60米）和季节变化（春季和秋季）对中国漓江岩溶河流系统中叶凋落物分解及相关养分通量的影响。我们研究了三种植物的叶凋落物分解情况：（林奈）里奇、布朗和小泉。它包括单物种和混合物种垃圾袋中的七种凋落物处理方式（所有单物种、两物种和三物种组合共3种）。2023年，在研究区域的三个海拔高度，共使用336个分解袋来测量两个为期六个月时间段内叶片质量损失和养分释放情况。结果表明，季节变化对初始叶片元素浓度有显著影响，春季样本的影响最为明显。海拔对质量损失的影响大于凋落物处理方式，不同海拔观察到明显的养分释放模式。在单物种中，在春季较低海拔处表现出最高的质量损失和养分释放，而在秋季高海拔处显示出最低速率。混合物种处理呈现出不同的分解模式，质量损失和养分释放顺序为：。混合物种中的养分释放与海拔和季节存在显著相互作用，表现出正、负非加性效应。相关性分析表明，与和相比，养分释放与质量损失之间的关系更强。本研究强调了岩溶河流系统中生物和非生物因素之间的复杂相互作用。它突出了在岩溶河流系统生态恢复工作中考虑海拔和季节动态的重要性。
