Universidade Federal do Pará, Campus Bragança, Laboratório de Ecologia de Manguezal, Bragança, Pará, Brazil.
Instituto Tecnológico Vale, Belém, Pará, Brazil.
PLoS One. 2020 Mar 10;15(3):e0230008. doi: 10.1371/journal.pone.0230008. eCollection 2020.
Reliable estimates of biomass and carbon storage are essential for the understanding of the environmental drivers and processes that regulate the productivity of scrub forests. The present study estimated total (above-ground, AGB + below-ground, BGB) biomass and carbon storage of a scrub forest dominated by Avicennia germinans (L.) L. based on the existing allometric models for the AGB, while novel models were developed to estimate the BGB. Data collection followed a destructive approach by using the "sampling method", from 45 trees divided into three height classes. Tree height and diameter were used to estimate the BGB of these forests, providing more accurate estimates of their biomass. Our findings indicate the existence of a direct relationship with increasing topography and interstitial salinity, which result in an increase in the percentage contribution of the AGB. By contrast, increasing topography also led to reduction in tree height and contribution of the BGB, although this compartment represents approximately half of the total biomass of these forests. The contribution of BGB estimates increased from 43 to 49.5% from the lowest to the highest height class and the BGB and AGB values reached approximately 87 Mg ha-1 (48.6%) and 91.7 Mg ha-1 (51.4%), respectively. The estimates of the biomass and carbon stocks of scrub mangroves vary considerably worldwide, which reflects the uncertainties derived from the application of distinct sampling methods. Specific models developed for each height class should be considered instead generalist models to reduce the general uncertainties on the production and distribution of biomass and the storage of carbon. Overall, our results overcome a major lacuna in the development of allometric equations to estimate the production of BGB and the storage of carbon by scrub mangrove forests, contributing to the refinement of the total biomass estimates for this type of mangrove forest.
可靠的生物量和碳储量估计对于理解调节 scrub 森林生产力的环境驱动因素和过程至关重要。本研究基于现有的地上生物量（AGB）的异速生长模型，估算了以海桑（Avicennia germinans （L.） L.）为主的 scrub 森林的总生物量（地上部分，AGB + 地下部分，BGB）和碳储量，同时还开发了新的模型来估算 BGB。数据收集采用破坏性方法，通过“采样方法”，从 45 棵树分为三个高度类别。树木高度和直径用于估算这些森林的 BGB，提供了更准确的生物量估计。我们的研究结果表明，地形和间隙盐度的增加与 AGB 的百分比贡献呈直接关系，这导致 AGB 的百分比增加。相比之下，地形的增加也导致了树木高度和 BGB 贡献的减少，尽管这个部分代表了这些森林总生物量的大约一半。从最低到最高的高度类别，BGB 估算的贡献从 43%增加到 49.5%，BGB 和 AGB 值分别达到约 87 Mg ha-1（48.6%）和 91.7 Mg ha-1（51.4%）。 scrub 红树林的生物量和碳储量估算在全球范围内差异很大，这反映了由于应用不同的采样方法而产生的不确定性。应考虑为每个高度类别开发的特定模型，而不是通用模型，以减少对生物量产生和分布以及碳储存的总体不确定性。总的来说，我们的研究结果弥补了开发估算 scrub 红树林 BGB 产量和碳储量的异速生长方程的主要空白，有助于细化这种红树林类型的总生物量估计。
