Matsuo Tomonari, Poorter Lourens, van der Sande Masha T, Mohammed Abdul Salim, Koyiba Dieudonne Wedaga, Opoku Justice, de Wit Bas, Kuzee Tijs, Amissah Lucy
Forest Ecology and Forest Management Group, Wageningen University, Wageningen, the Netherlands.
CSIR-Forestry Research Institute of Ghana, Kumasi, Ghana.
Ecology. 2025 Jan;106(1):e4488. doi: 10.1002/ecy.4488. Epub 2024 Dec 4.
Young tropical secondary forests play an important role in the local and global carbon cycles because of their large area and rapid biomass accumulation rates. This study examines how environmental conditions and forest attributes shape biomass compartments and the productivity of young tropical secondary forests. We compared 36 young secondary forest stands that differed in the time since agricultural land abandonment (2.3-3.6 years) from dry and wet regions in Ghana. We quantified biomass stocks in living and dead stems, roots, and soil, and aboveground biomass and litter productivity. We used structural equation models to evaluate how macroclimate, soil nutrients (N, P), and forest attributes (structure, diversity, and functional composition) affect ecosystem functioning. After three years of succession, tropical wet forests stored on average 115 t biomass ha (the sum of aboveground living and dead biomass, belowground fine root biomass, and soil organic matter), and dry forests stored 99 t ha. These values represent 31% (in the wet forest) and 39% (in the dry forest) of the biomass compared with neighboring old-growth forests. The majority of forest ecosystem biomass was stored in the soil (70%) and aboveground living vegetation (25%). Macroclimate strongly shaped forest attributes, which in turn determined biomass stocks and productivity. Soil phosphorus strongly increased litter production and soil organic matter, confirming that it is a limiting element in tropical ecosystems. Tree density and species diversity increased forest biomass stocks, suggesting crown packing and complementary resource use enhance forest functioning. A more conservative trait composition (high wood density) increased biomass stocks but reduced productivity, indicating that quantity, identity, and quality of species affect ecosystem functioning.
年轻的热带次生林因其面积广阔和生物量积累速度快，在地方和全球碳循环中发挥着重要作用。本研究探讨了环境条件和森林属性如何塑造年轻热带次生林的生物量组成部分和生产力。我们比较了加纳干旱和湿润地区36个年轻次生林分，这些林分自弃耕农田以来的时间不同（2.3 - 3.6年）。我们对活立木、死木、根系和土壤中的生物量储量，以及地上生物量和凋落物生产力进行了量化。我们使用结构方程模型来评估宏观气候、土壤养分（氮、磷）和森林属性（结构、多样性和功能组成）如何影响生态系统功能。经过三年的演替，热带湿润森林平均每公顷储存115吨生物量（地上活立木和死木生物量、地下细根生物量和土壤有机质之和），干旱森林每公顷储存99吨。与相邻的原始森林相比，这些数值分别占生物量的31%（湿润森林）和39%（干旱森林）。森林生态系统的大部分生物量储存在土壤中（70%）和地上活植被中（25%）。宏观气候强烈塑造了森林属性，而森林属性又反过来决定了生物量储量和生产力。土壤磷显著增加了凋落物产量和土壤有机质，证实了它是热带生态系统中的一个限制元素。树木密度和物种多样性增加了森林生物量储量，表明树冠郁闭和资源互补利用增强了森林功能。更保守的性状组成（高木材密度）增加了生物量储量，但降低了生产力，表明物种的数量、特性和质量会影响生态系统功能。
