Interspecific variation of tree root architecture in a temperate agroforestry system characterized using ground-penetrating radar
Interspecific variation of tree root architecture in a temperate agroforestry system characterized using ground-penetrating radar
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DOI：
10.1007/s11104-016-3015-x
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发表时间：
2016
期刊：
影响因子：
4.9
通讯作者：
Kira A. Borden;S. Thomas;M. Isaac
中科院分区：
文献类型：
--
作者：
Kira A. Borden;S. Thomas;M. Isaac
根系统结构调节地下土壤资源的获取。在农林复合系统中，根构型的变化是重要的，因为管理目标是优化树木和作物之间的资源获取。然而，由于方法上的限制，在农林复合系统中活树根的分布仍然研究不足。在这项研究中，我们使用探地雷达（GPR）来描述在同一农业站点的树种之间的全植物根构型的变化，特别关注与邻近作物竞争区域内的垂直粗根和细根分布。黑胡桃，美洲黑杨（Populus deltoides× nigraDN 177）、欧洲云杉（Picea abies（L.）喀斯特（Karst）和北美崖柏（Thuja oceanentalisL.）在加拿大安大略南部的一个以树木为基础的间作系统。土壤剖面的一个子集进行了评估的GPR精度。用累积根分布函数估算粗根的生根深度（D95）。我们还测量了竞争区作物行内2 m处的树木粗根分布和细根密度分布。结果探地雷达准确地检测到每棵研究树木约58%的粗根。粗根构型因物种而异，D95和生根模式存在差异。细根长度密度分布也各不相同的物种，但始终高0.10和0.20米的深度，无论species.ConclusionsOur结果表明，差分树适合最大限度地减少地下与作物的竞争。此外，我们说明了GPR的可行性，以表征垂直配置文件的活树根系统，这是至关重要的，提高我们的理解全植物的功能特性和地下植物的相互作用。
Background and aimsRoot system architecture regulates belowground access to soil resources. Variation in root architecture is important in agroforestry systems given management objectives to optimize resource acquisition between trees and crops. However, the distributions of live tree roots in agroforestry systems remain understudied due to methodological constraints. In this study, we used ground-penetrating radar (GPR) to describe variation in whole-plant root architecture among tree species at the same agricultural site, with a specific focus on vertical coarse and fine root distributions within the zone of competition with neighbouring crops.MethodsUsing GPR, we detected coarse roots of five trees species (Quercus rubraL.,Juglans nigraL.,Populus deltoides×nigraDN177,Picea abies(L.) Karst, andThuja occidentalisL.) at a tree-based intercropping system in southern Ontario, Canada. A subset of soil profiles were assessed for GPR accuracy. A cumulative root distribution function was used to estimate the rooting depth (D95) of coarse roots. We also measured tree coarse root distributions and fine root density distributions 2 m into the crop rows, in the zone of competition.ResultsGPR accurately detected approximately 58 % of coarse roots for each study tree. Coarse root architecture varied among species, with differences in D95and rooting patterns. Fine root length density distribution also varied among species, but was consistently high at 0.10 and 0.20 m depths regardless of species.ConclusionsOur results suggest differential tree suitability for minimizing belowground competition with crops. Additionally, we illustrate the viability of GPR to characterize vertical profiles of live tree root systems, which is critical for improving our understanding of whole-plant functional traits and belowground plant interactions.