Mineralization ratios of nitrogen and phosphorus from decomposing litter in temperate versus tropical forests

• DOI: 10.1111/geb.12414
• Publication Date: 2015-12-23T06:42:45Z
• Authors: Alison R. Marklein; Joy B. Winbourne; Sara K. Enders; David J. X. Gonzalez; Tiff L. van Huysen; Jorge E. Izquierdo; Derrick R. Light; Daniel Liptzin; Kimberley E. Miller; Scott L. Morford; Robert A. Norton; Benjamin Z. Houlton
• Keywords: 0106 biological sciences; 2. Zero hunger; 13. Climate action; 15. Life on land; 01 natural sciences; 12. Responsible consumption

AbstractAimTerrestrial ecosystems sequester about 25% of anthropogenic CO2emissions annually; however, nitrogen (N) and phosphorus (P) limitation of plant productivity and microbial functioning could curtail this key ecosystem service in the future. Our aim is to address variations in nutrient resupply during decomposition – especially whether theN:Pratio of nutrient recycling via mineralization varies within and across diverse forest biomes.LocationGlobal forest ecosystems.MethodsWe compiled data onin situlitter decomposition experiments (leaf, wood and root) from the primary literature to examine the relationships between netNandPmineralization across temperate versus tropical forests world‐wide. We define net nutrient mineralization ratios as the averageN:Preleased from decomposing substrates at a given ecosystem site.ResultsWe show that netNandPmineralization are strongly correlated within biomes, suggesting strong coupling betweenNandPrecycling in forest ecosystems. The netN:Pof leaf‐litter mineralization is higher in tropical forests than in temperate forests, consistent with latitudinal patterns in foliar and leaf‐litterN:P. At the global scale, theN:Pof net mineralization tracks, but tends to be lower than that of litterN:P, pointing to preferentialP(versusN) mineralization in forest ecosystems.Main conclusionsOur results do not support the view that there is a single, globally consistent mineralizationN:Pratio. Instead, our results show that theN:Pof net mineralization can be predicted by theN:Pof litter, offering a method for incorporatingPinto global‐scale models of carbon–nutrient–climate interactions. In addition, these results imply thatPis scarce relative to microbial decomposer demands in tropical forests, whereasNandPmay be more co‐limiting when compared with microbial biomass in the temperate zone.