Does initial litter chemistry explain litter mixture effects on decomposition?

Abstract

We tested the hypothesis that interactions in litter mixtures (expressed as the difference between observed and expected decomposition rates) are greater when the component species differ more in their initial litter chemistry. Thereto, we collected freshly senesced leaf litter from a wide range of species from an old field and woodland vegetation, and a fen ecosystem in The Netherlands. Litterbags with either mono-specific litter (20 and 15 species), or litter mixtures (50 and 42 species pairs) of randomly drawn combinations of two representatives from different plant functional types were incubated for 20, 35 and 54 weeks in a purpose-built decomposition bed (woodland/old field) or in the field (fen). Species showed a wide range of decomposition rates. For the woodland/old field species, initial litter C and P concentrations were significantly correlated with litter decomposition rate. For the fen species, litter phenolics concentration was correlated with decomposition rate. If the Sphagnum species were left out of the analyses, initial litter P and phenolics concentration both showed a significant relationship, albeit only with the remaining mass after 1 year. Differences between observed and expected decomposition were often considerable in individual litter mixtures. Regression analysis showed that such differences were not related to the differences in litter chemistry of the component species. Furthermore, litter mixtures containing species with very different initial litter chemistry did not show stronger interaction when tested against litter mixtures containing chemically similar litter types. From these observations we conclude that the difference in initial single litter chemistry parameters of the component is not a useful concept to explain interactions in litter mixtures.

Litterfall Production and Nutrient Deposition Through Leaf Fallen in three Tamaulipan Thornscrub Communities, North-eastern Mexico

“…In addition, the factors which control its degradation are the physicochemical environment, and litterfall and the composition of the community of decompossers . The present study is supported by the results observed by Hoorens et al (2003) and Zhang et al (2008) whose reports about the quality of litterfall determines to some extent the grade of descomposition in the majority of terrestrial ecosystems which are realted to a great diversity of plant species which implies that its composition exerts a strong impact in this respect (Hattenschwiler, 2005).…”

“…The main elements which control its degradation are the physicochemical environment, the characteristics of litterfall and the biotic elements involved during decomposition . Hoorens et al (2003) and Zhang et al (2008) have shown that the quality of litterfall is one of the limiting factors which affects the rate of descomposition so that the majority of terrestrial ecosystems are integrated by a great variety of plant species, by which each contribute to the anual process, which implies that its composition exert a strong impact on this respect . On the other hand, Tuomi et al (2009) indicates that temperature and precipitation are key factors which affect degradation.…”

Seasonal Pattern of Decomposition and N, P, and C Dynamics in Leaf litter in a Mongolian Oak Forest and a Korean Pine Plantation

“…The leaf litter decomposition rate of the mixed leaf litter could therefore be predicted from the decomposition rate of each individual species [15]. Mixed leaf litter could have a higher decomposition rate than a single-species leaf litter because nutrient exchange among leaf litters of different species through microbes could enhance the nutrient condition of low-quality leaf litters, accelerating the decomposition rate [27,42].…”

“…However, limited information is available on the effects of a plantation on nutrient cycling at a site and on plantation interactions with existing ecosystems [14]. Thus, an increasing number of studies investigate the effect of certain species on the decomposition of single or mixed leaf litters for better plantation management or restoration of natural stands [15,16]. Those studies simultaneously integrate features of species, mixed leaf litters, and forest floor conditions by forest type to explain the leaf litter decomposition process [17,18].…”

Non-additive effects of water availability and litter quality on decomposition of litter mixtures

“…The expected mass that remained in mixed-litter treatments was estimated based on the mass remaining in single-litter bags from the same string as follows (Hoorens et al 2003):…”