林冠穿透雨空间异质性(即不同冠层位置穿透雨量的非均一性)及其在一定时间段内的持续性(即时间稳定性)关系着土壤水分补给数量和效率，通过影响资源有效性作用于植物个体竞争和群落演替。本研究基于关键词检索并分析整理了 Web of Science和中国知网数据库2000-2022年发表的554篇相关主题论文数据，量化并对比了全球不同气候带和植物功能型的穿透雨数量、空间异质性及其时间稳定性特征。结果表明:全球范围内旱区穿透雨比例(72。0％±13。6％)小于湿润(75。1％±9。3％)和半湿润区(79。9％±10。4％)，热带(80。9％±14。6％)高于暖温带(74。2％±7。5％)和冷温带(74。1％±14。6％)，灌木(68。9％±14。9％)小于乔木(76。7％±9。1％)，但阔叶植物(75。2％±11。1％)和针叶植物(75。1％±9。9％)、常绿植物(76。7％±10。0％)和落叶植物(74。7％±11。9％)的林冠穿透雨比例接近，其空间变异系数在上述不同干湿区、温度带和植物功能型之间差异均不显著。穿透雨空间分布格局易保持相对稳定，冠层结构是影响其时间稳定性的主导因子，但缺乏不同时间尺度上典型地理单元(即地理环境条件基本一致的空间单元)之间的对比。建议未来研究通过向上延展至基于全球的空间尺度规律汇总，向下延展至基于过程的时间尺度机制分析，刻画穿透雨空间分布动态变化，并统一观测规范来增进不同研究之间的可参比性，以高效推进林冠穿透雨研究，为保护自然、管理人工、恢复受损生态系统提供生态水文依据。
Global quantification of the spatial variability and temporal stability of throughfall
Spatial variability of throughfall(i.e.the non-uniform characteristics of throughfall at different canopy positions)and its temporal persistence(i.e.time stability)are related to the quantity and efficiency of soil moisture replenishment,and affect plant competition and community succession dynamics by affecting resource availability.We carried out a meta-analysis with 554 papers(from 2000 to 2022)retrieved from Web of Science and China National Knowledge Infrastructure(CNKI)based on keyword search,quantified and compared the amount,spatial heteroge-neity,and temporal stability characteristics of penetrating rain in different climate zones and plant functional types.Our results that throughfall proportion was lower in arid regions(72.0％±13.6％)than humid(75.1％±9.3％)and semi-humid areas(79.9％±10.4％).Cold climates had lower values(74.1％±14.6％)than temperate(74.2％±7.5％)and tropical climates(80.9％±14.6％).Shrubs(68.9％±14.9％)generally had lower throughfall propor-tion than trees(76.7％±9.1％).Broad-leaved trees(75.2％±11.1％)and conifers(75.1％±9.9％)showed similar throughfall proportions,as did evergreen(76.7％±10.0％)and deciduous species(74.7％±11.9％).Additionally,spatial variability(coefficient of variation)did not significantly differ across rainfall zones,temperature zones,or vegetation types.The spatial distribution of throughfall was relatively stable.Canopy structure was the dominant fac-tor affecting temporal stability of throughfall.However,there was a lack of comparison between typical geographic units(i.e.spatial units with basically consistent geographical environmental conditions)at various temporal scales.Future research should expand upwards to the summary of global spatial scale rules and downwards to the analysis of process based temporal scale mechanisms,to depict the dynamic distribution of penetrating rain and unify observa-tion standards to enhance comparability of different studies,in order to efficiently promote research on canopy pene-trating rain and provide ecological and hydrological basis for protecting nature,managing artificial activities,and restoring degraded ecosystems.
国家科技期刊平台
NSTL
万方数据
