Fineroots (≤ 2 mm diameter) are dynamic components of the forest ecosystems and play important role in water and nutrient acquisition in forests. These roots are sensitive to forest fertilization and therefore, the response of fineroots to nutrient application would provide better understanding of the forest carbon and nutrient dynamics that will be helpful in sustainable forest management plans. Two fertilization treatments, including (1) F400: 400 g P₂O₅ (16.5%)/tree and (2) F600: 600 g P₂O₅ /tree, and F0: control (without fertilization), were applied in an Acacia mangium plantation with a planting density of 1100 trees/ha (3 m × 3 m). The evaluation of fineroot growth across seasons showed that fertilization significantly increased production and subsequent mortality and decomposition. The total decomposition associated with F600 application was 7.95 tons ha⁻¹ year⁻¹, equaling 121% of F400 and 160% of the control. Mortality in F600 was 8.75 tons ha⁻¹ year⁻¹, equaling 111% of F400 and 198% of F0, while production in F600 was 10.40 tons ha⁻¹ year⁻¹, equaling 127% of F400 and 143% of F0. Fineroot production, mortality, and decomposition are seasonally dependent, with higher values measured in the rainy season than in the dry season. Stand basal area increment was significantly correlated with fineroot production (R² = 0.75), mortality (R² = 0.44), and decomposition (R² = 0.48). This study showed that fertilization could facilitate fineroot production, which can then lead to a higher turnover of carbon and nutrients through the decomposition of the greater mass of the fineroots.

中文翻译：

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越南相思树人工林细根生长动态变化对磷的响应

细根（直径≤2 mm）是森林生态系统的动态组成部分，在森林的水和养分获取中起着重要作用。这些根对森林施肥敏感，因此，细根对养分施用的反应将使人们更好地了解森林的碳和养分动态，这将有助于可持续森林管理计划。两种施肥处理包括：（1）F400：400 g P ₂ O ₅（16.5％）/棵和（2）F600：600 g P ₂ O ₅ /树，以及F0：对照（不施肥）。马占相思种植密度为1100棵/公顷（3 m×3 m）的人工林。对不同季节的细根生长的评估表明，施肥显着提高了产量，进而导致死亡率和分解。与F600施用相关的总分解为7.95吨ha - ¹年^-1，相当于F400的121％和对照的160％。F600的死亡率为8.75吨ha - ¹年^-1，相当于F400的111％和F0的198％，而F600的产量为10.40吨ha - ¹年^-1，等于F400的127％和F0的143％。细根的产量，死亡率和分解取决于季节，在雨季测得的值高于旱季。林分基础面积的增加与细根产量（R ²  = 0.75），死亡率（R ²  = 0.44）和分解（R ²  = 0.48）显着相关。这项研究表明，施肥可以促进细根的产生，然后通过分解更大数量的细根而导致更高的碳和养分周转率。