Key message

We provide a set of allometric models for wild cherry trees (Prunus avium L.) established in agroforestry systems. A total of 70 trees in southwestern Germany were surveyed using terrestrial laser scanning and analysed using quantitative structure models. The derived allometric models provide a stable base for biomass estimation in comparable agroforestry systems. Our biomass model, based on volume estimates converted to biomass, shows no significant differences to a previous study in the same region on the same species, although it was conducted on agroforestry trees under a different management regime.

Context

Wild cherry (Prunus avium L.) is a common tree species in agroforestry systems (AFS). Utilised for either fruit production or for high-value timber production, it is a highly relevant species, yet even basic allometric models are lacking.

Aims

The aim of this study was to develop a set of allometric models for wild cherry trees in AFS. Within this context, we present an innovative non-destructive approach to estimate bark and wood volume separately by applying bark thickness models to 3D models of trees. To assess model applicability to different AFS, we compared our allometric model for above-ground biomass with a previous biomass model for wild cherry trees under different management in the same region.

Methods

Wild cherry trees (n = 70) located within AFS in southern Germany were scanned with a terrestrial laser scanner. Quantitative structure models were used to derive tree dimensions and above-ground volume per tree. Using additional auxiliary data, the target variables were derived, and corresponding allometric models were fitted.

Results

The allometric models estimating above-ground volume, oven-dry biomass, carbon content and nutrient content based on diameter at breast height (DBH) showed excellent fits (R²_adj ≥ 0.97). The comparisons with a similar study conducted in the same region suggested that management practices such as pruning have only a minor influence on the relationship between DBH and above-ground tree biomass. The nutrient content in the trees decreased in the order Ca > N > K > Mg > P.

Conclusions

The derived allometric models provide valuable information on this important agroforestry tree species. Our findings can both inform management practices in AFS and advance ecological understanding of these systems. Future research should focus on developing allometric models for other tree species relevant to AFS.

中文翻译：

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农林复合系统中野樱桃树地上生物量、碳和养分含量的异速生长模型

关键信息

我们提供了一套在农林复合系统中建立的野樱桃树（ Prunus avium L.）的异速生长模型。使用地面激光扫描对德国西南部总共 70 棵树进行了调查，并使用定量结构模型进行了分析。导出的异速生长模型为可比农林业系统中的生物量估算提供了稳定的基础。我们的生物量模型基于转换为生物量的体积估计，与之前在同一地区对同一物种进行的研究没有显着差异，尽管它是在不同管理制度下的农林业树木上进行的。

语境

野樱桃（Prunus avium L.）是农林复合系统（AFS）中的常见树种。它用于水果生产或高价值木材生产，是一个高度相关的物种，但甚至缺乏基本的异速生长模型。

目标

本研究的目的是开发一套 AFS 中野樱桃树的异速生长模型。在此背景下，我们提出了一种创新的非破坏性方法，通过将树皮厚度模型应用于树木的 3D 模型来分别估计树皮和木材体积。为了评估模型对不同 AFS 的适用性，我们将地上生物量的异速生长模型与同一地区不同管理下野樱桃树的先前生物量模型进行了比较。

方法

 使用地面激光扫描仪扫描了德国南部 AFS 内的野樱桃树（n = 70）。定量结构模型用于推导树木尺寸和每棵树的地上体积。使用额外的辅助数据，导出目标变量，并拟合相应的异速生长模型。

结果

基于胸径 (DBH) 估算地上体积、绝干生物量、碳含量和养分含量的异速生长模型显示出极好的拟合度 ( R ² _adj  ≥ 0.97)。与同一地区进行的类似研究的比较表明，修剪等管理措施对胸径和地上树木生物量之间的关系影响很小。树木养分含量依次递减：Ca > N > K > Mg > P。

结论

衍生的异速生长模型提供了有关这一重要农林业树种的宝贵信息。我们的研究结果既可以为 AFS 的管理实践提供信息，又可以促进对这些系统的生态理解。未来的研究应集中于开发与 AFS 相关的其他树种的异速生长模型。