Table 1 Fine root contribution to net primary productivity (mean ± SE; Mg C ha−1 year−1) and responses of fine root biomass (FRB) or fine root production (FRP) to nutrient additions in tropical forests.
From: Nitrogen and potassium limit fine root growth in a humid Afrotropical forest
Location | Soil group (FAO classification) | NPP total | NPPfine litter | NPPwood | NPPfine root (Soil depth) | Response to nutrient additions | References |
|---|---|---|---|---|---|---|---|
Uganda | Lixisols | 9.5 ± 0.9 | 6.4 ± 0.4 | 2.2 ± 0.4 | 1.2 ± 0.1 (30 cm) | FRB decreased with N and K; FRP decreased with K | This study; Manu et al.9 |
Panama | Cambisols/Nitisols | 9.3 | 5.7 | 2.1 | 1.5 (20 cm) | FRB decreased with K | |
Amazonia | Ferralsols | 7.4 ± 0.2 | 4.4 ± 0.1 | 1.9 | 1.2 ± 0.1 (30 cm) | FRP increased with P | Cunha et al.8 |
Costa Rica | Cambisols | 8.5 | 3.5 | 4.2 ± 1.1 | 0.8 ± 0.1 (15 cm) | FRP increased with P | Waring et al.73 |
Ecuador | Cambisols | – | 1.8 | – | 3.2 (20 cm) | FRB decreased with P | Homeier et al.85 |
Ecuador | Acrisols | – | – | – | – (15 cm) | FRB increased with N, P, and K | Graefe et al.86 |
Panama | Andosols | 8.3 | 4.4 | 2.3 | 1.6 (20 cm) | FRB increased with N | Adamek et al.50 |
Costa Rica | – | – | – | – | 0.4 ± 0.0 (10 cm) | FRB-unresponsive to N and P | Alvarez et al.64 |
