Page 162 - 《广西植物》2026年第6期
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6 期              覃志伟等: 广西大瑶山保护区不同森林类型凋落物的持水与失水特性                                          1 0 7 7

                    ( 1. Guangxi Forest Resources and Environment Monitoring Centerꎬ Nanning 530028ꎬ Chinaꎻ 2. Guangxi Dayaoshan Forest
                           Ecosystem Observation and Research Stationꎬ Laibin 545700ꎬ Guangxiꎬ Chinaꎻ 3. Guangxi Dayaoshan
                                  National Nature Reserve Management Centerꎬ Laibin 545700ꎬ Guangxiꎬ China )


                 Abstract: The water ̄holding and water ̄losing characteristics of forest litter are critical components regulating hydrological
                 processes in forest ecosystems. Howeverꎬ the quantitative characterization and analysis of the hydrological functions of the
                 litter layer across different forest types remain largely inadequate to date. To clarify the water ̄holding and water ̄losing
                 characteristics of litter in major forest types in the Dayaoshan National Nature Reserveꎬ Guangxiꎬ this study employed a
                 combination of field plot surveys and laboratory ̄controlled experiments to determine the litter standing cropꎬ water ̄holding
                 dynamic processesꎬ and water ̄losing dynamic processes of three typical forest types in the reserveꎬ namely evergreen
                 broadleaf forest (EBF)ꎬ mixed coniferous ̄broadleaf forest (MCBF)ꎬ and montane elfin forest (MEF). Furthermoreꎬ their
                 water conservation capacity was evaluated. The results were as follows: (1) The total litter accumulation of three forest types
                                         ̄2
                 ranged from 2.28 to 5.33 thm ꎬ with the order of EBF> MCBF> MEF. (2) The relationship between water ̄holding
                 capacity (Q) and immersion time (t) followed the logarithmic function [Q = aln(t) +b]ꎬ and the relationship between
                                                                             n
                 water ̄absorption rate (V) and immersion time (t) followed the power function (V=kt )ꎻ there was a significant logarithmic
                                                                2
                 relationship between water ̄losing capacity and seasoning time (R >0.95ꎬ P<0.05)ꎬ whereas a significant power function
                                                                    2
                 relationship was found between water ̄losing rate and seasoning time (R >0.95ꎬ P<0.05). (3) The effective interception
                                                                                              ̄2
                 rate ranged from 49.46% to 116.13%ꎬ and the effective interception capacity ranged from 0.41 to 3.09 thm . Among themꎬ
                 the effective interception capacity of EBF and MCBF was significantly higher than that of MEF (P<0.05). In conclusionꎬ
                 there were significant differences in the hydrological regulation efficiency of litter among different forest types in the
                 Dayaoshan Reserveꎬ Guangxi. EBF not only had the highest rainfall interception capacity but also exhibited better
                 coordination between water ̄holding and water ̄losing. The results of this study provide empirical basis and parameter support
                 for the accurate evaluation of water conservation functionsꎬ quantification of ecological benefitsꎬ and protection and
                 management decisions of subtropical montane forests.
                 Key words: Guangxi Dayaoshanꎬ forest hydrologyꎬ litterꎬ water ̄holding capacityꎬ effective interception capacityꎬ
                 hydrological effect



                森林凋落物是森林生态系统物质循环与能量                            物调控因子ꎬ凋落物水文效应研究已成为生态学、
            流动的关键载体ꎬ不仅通过降解过程持续释放氮、                             水文学与森林生态学交叉领域的前沿热点ꎮ 当
            磷、钾等养分以维持系统功能稳定ꎬ更在土壤发                              前ꎬ大量工作聚焦于不同区域、不同森林类型凋落
            育、养分归还及水土保持中发挥着不可替代的生                              物现存量及其持水特征的区域性观测与影响机制
            态作用( 曹云等ꎬ2006ꎻ王千军等ꎬ2012)ꎮ 作为大                      解析ꎮ 有研究表明ꎬ凋落物持水能力受自身性状、
            气降水与矿质土壤间的天然缓冲层ꎬ凋落物可通                              分解程度、凋落物现存量及外部环境共同调控ꎬ其
            过截留降水有效减缓雨滴对地表土壤的溅蚀、延                              中现存量是决定持水总量的首要结构性因子ꎬ而
            迟地表径流形成时间ꎬ并显著提升水分向土壤深                              树种组成则主导持水动力学特性ꎮ 例如ꎬ刘蕾等
            层的 下 渗 效 率ꎬ 从 而 有 效 降 低 水 土 流 失 风 险                (2012)发现神农架不同海拔森林的凋落物现存量
            (Maguireꎬ1994ꎻ何娇等ꎬ2023ꎻ陈夙 怡 等ꎬ2024)ꎮ               及持水特征具有规律性差异ꎻ魏强等(2011) 指出
            此外ꎬ凋落物分解产生的腐殖质可显著优化土壤                              甘肃兴隆山不同林型间凋落物累积量与持水性存
            孔隙结构的合理性与稳定性( 惠欣荣ꎬ2019)ꎬ在增                         在显著区别ꎮ 然而ꎬ关于针叶林、阔叶林与混交林
            强土壤抗侵蚀能力及持水保水潜能的同时ꎬ为森                              三类典型林型持水能力的优劣排序ꎬ学术界尚未
            林涵养水源功能的高效发挥提供重要物质支撑ꎮ                              形成共识ꎮ 多数研究支持阔叶林凋落物因质地疏
                 近年来ꎬ受全球气候变化影响ꎬ极端降水、干                          松和孔隙发达而具有更高持水容量( 丁咸庆等ꎬ
            旱等气候事件频发ꎬ森林生态系统水文调节功能                              2021ꎻ王亚萍等ꎬ2024ꎻ谢建文等ꎬ2024)ꎻ但也有研
            的重要性愈发凸显ꎮ 作为生态水文过程的关键生                             究表明ꎬ针叶林凋落物因蜡质层厚、分解缓慢ꎬ在
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