Andean grasslands are as productive as tropical cloud forests

Andean grasslands exhibit net primary productivity (NPP) comparable to tropical montane cloud forests, challenging assumptions about carbon cycling in these ecosystems. The study, conducted in southeastern Peruvian Andes including sites within Manu National Park, found NPP ranging from 4.6 to 15.3 Mg C ha⁻¹ yr⁻¹ in grasslands and 7.05 to 8.0 Mg C ha⁻¹ yr⁻¹ in cloud forests, with no significant differences between the two. Undisturbed grassland sites showed significantly higher productivity than disturbed ones, though grazing and fire effects varied. Soil carbon stocks were substantial (126–285 Mg C ha⁻¹), but grasslands demonstrated faster above-ground biomass turnover compared to below-ground biomass. Seasonal shifts in NPP allocation were observed, particularly at the onset of austral summer. These findings highlight the resilience and productivity of high-elevation tropical grasslands, contrasting with the carbon retention properties of cloud forests.

Oliveras, I., Girardin, C., Doughty, C. E., Cahuana, N., Arenas, C. E., Oliver, V., Huaraca Huasco, W., & Malhi, Y. (2014). Andean grasslands are as productive as tropical cloud forests. Environmental Research Letters, 9(11), 115011. https://doi.org/10.1088/1748-9326/9/11/115011