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The carbon:nutrient ratio of plants is generally larger than that of soil bacteria and fungi, indicating an imbalance between the supply and demand for nutrients during decomposition (Hessen et al., 2004; Sterner & Elser, 2002). Indeed, litter decomposition studies often show an increase in nutrient concentrations over time, reflecting microbial immobilization of nutrients from the environment (e.g., Conner & Day, 1991). Litter decomposition is sensitive to nutrient availability in plant litter (Enríquez et al., 1993; Webster & Benfield, 1986) and/or the environment (Rejmánková & Houdková, 2006; Song et al., 2011). The degradation of plant litter can be limited by nitrogen availability, as indicated by negative correlations between litter C:N ratios and rates of decomposition (Keuskamp et al., 2015; Lee & Bukaveckas, 2002; Neely & Davis, 1985; Song et al., 2011). A similar pattern is seen with phosphorus (P), where higher litter phosphorus levels can lead to higher decomposition rates (J. Hines et al., 2014). The decomposition of leaf litter is generally limited by phosphorus when leaf N:P ratios are high and by nitrogen when leaf N:P ratios are low. Although there is not a universal N:P ratio that determines when the limiting nutrient changes (Güsewell & Freeman, 2005; Güsewell & Verhoeven, 2006), plants growing in organic wetland soils are more likely to be limited by phosphorus whereas plants in mineral substrates often are limited by nitrogen availability (Bedford et al., 1999). There can be interactions between nutrient availability and carbon quality, with higher nutrient levels stimulating decomposition to a greater degree when leaf litter is of higher quality (i.e., lower lignin content) (Hobbie, 2000). Alternately, the effects of low carbon quality may limit decomposition regardless of nutrient availability (Bridgham & Richardson, 2003).