What factors are most influential in governing stemflow production from plantation-grown teak trees?
What factors are most influential in governing stemflow production from plantation-grown teak trees?
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DOI：
10.1016/j.jhydrol.2016.11.010
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发表时间：
2017
影响因子：
6.4
通讯作者：
N. Tanaka;D. Levia;Yasunori Igarashi;N. Yoshifuji;Katsunori Tanaka;C. Tantasirin;K. Nanko;Masakazu Suzuki;T. Kumagai
中科院分区：
文献类型：
--
作者：
N. Tanaka;D. Levia;Yasunori Igarashi;N. Yoshifuji;Katsunori Tanaka;C. Tantasirin;K. Nanko;Masakazu Suzuki;T. Kumagai
Stemflow (SF) 已被认为是向森林地面空间局部区域输送水的重要过程。本研究基于泰国种植园九棵柚木近六年的每日 SF 数据，以及详细的树冠上方气象数据和每日叶面积指数 (LAI) 数据，旨在更好地了解特定的生物和非生物因素如何影响柚木个体和林分规模的 SF 产量。具体而言，通过提升回归树（BRT）分析，对影响个体和林分尺度的茎流漏斗率（SFFR）的因素进行了分析和比较。在有叶状态下观察到各个柚木树之间 SFFR 的最大变化。对于高于平均水平的树木，BRT 分析显示，降雨期间的水汽压不足是影响 SFFR 的最大因素。蒸气压不足对 SFFR 有负面影响，这意味着降雨期间对蒸发需求的显着控制。相比之下，对于低于平均水平的树木，降雨持续时间 (RD) 是最有影响力的变量，与 SFFR 呈正相关。对所有九棵柚木树的林分规模 BRT 分析表明，RD 是影响 SFFR（发挥积极影响）的最有影响力的因素，但一系列其他因素（非生物和生物）在控制 SFFR 中发挥着错综复杂的作用。 LAI 对 SFFR 的影响很复杂，并且不同柚木树之间差异很大。柚木树冠内拦截水的空间异质流路（可能是柚木大尺寸成熟叶子的产物）可能解释了 SFFR 对 LAI 变化的响应中树与树之间的差异。尽管我们的研究重点是柚木，但所证明的基于物理的茎流产生机制解释可以适用于其他同龄落叶林和单一种植园。
Stemflow (SF) has been recognized as an important process delivering water to spatially localized areas of the forest floor. Based on almost six years of daily SF data from nine teak trees in a Thai plantation, together with detailed above-canopy meteorological data and daily leaf area index (LAI) data, this study sought to better understand how specific biotic and abiotic factors affect both individual and stand-scale SF production from teak trees. Specifically, the factors affecting stemflow funneling ratio (SFFR) at individual and stand scales were analyzed and compared by means of boosted regression tree (BRT) analysis. The largest variation of SFFR among individual teak trees was observed in the leafed state. For trees taller than average, the BRT analysis revealed that vapor pressure deficit during rain was the most influential factor affecting SFFR. Vapor pressure deficit had a negative influence on SFFR, implying significant control of evaporative demand during rain. In contrast, for trees shorter than the average, rain duration (RD) was the most influential variable, having a positive correlation with SFFR. The stand-scale BRT analysis for all nine teak trees demonstrated thatRDwas the most influential factor affecting SFFR (exerting positive influence) but that an array of other factors (both abiotic and biotic) played intricate and complex roles in governing SFFR. The effect of LAI on SFFR was complicated and varied greatly among individual teak trees. It is possible that spatially heterogeneous flowpaths of intercepted water inside the teak canopy, which could be a product of the large-sized mature leaves of teak, may account for the tree-to-tree variation in the responses of SFFR to changing LAI. Although our study focused on teak trees, the demonstrated physically-based mechanistic explanations of stemflow production could apply to other even-aged deciduous forests and monospecific plantations.