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Litter decomposition mobilizes nutrients that sustain ecosystem productivity, but decomposition by‐products may also hamper root proliferation by phytotoxicity. The aim of this study was to assess the litter substrate preferences of tropical tree seedlings in relation to litter chemical traits. We characterized 44 litter types (11 species at four decomposition ages; 0, 30, 90 and 180 days) for nutrients (N, P, K, Mg, Mn, Na, Fe and Zn) and proximate chemical parameters (cellulose, extractive, lignin and C) and tested the effect of such litter materials on seedling root growth of Albizia procera, Dalbergia sissoo and Terminalia arjuna. Albizia procera root growth was inhibited by all litter types and ages, including conspecific materials, while different heterospecific litters had inhibitory or stimulatory effect on D. sissoo and T. arjuna root growth, compared to the control. Interestingly, inhibitory and stimulatory effects of heterospecific litters significantly changed with litter age, although with no clear‐cut pattern among target species and litter species and age, while conspecific litters consistently inhibited root growth when aged, but not when fresh. Litter nutrient, extractive, C, cellulose and lignin showed no consistent association with root growth of tested plants. Albizia procera root growth was positively associated with Na content and N:P ratio. Dalbergia sissoo root growth was positively associated to C:N and lignin:N ratios, and negatively to K, Na and Zn content. Finally, T. arjuna root was positively associated to cellulose and N:P ratio, but negatively to extractive. We conclude that studied nutrient, cellulose and lignin do not consistently explain the species‐specific response of root of tree seedlings to decomposing litter. [ABSTRACT FROM AUTHOR]

Background and aim: Litter decomposition is of great concern as it plays a key role in regulating global carbon cycle and nutrient budgets, especially in tropical forests where it is very fast. Therefore, we studied the decomposition and subsequent changes in element concentrations and amounts of 11 tropical leaf litter.Methods: Fresh litters were characterized in terms of elemental, proximate features, as well as organic carbon compositions by 13C-NMR spectroscopy. Controlled litterbag decomposition was carried out for 180 days in the laboratory, bags were retrieved at three dates and analyzed for mass loss and concentration of nitrogen (N), potassium (K), sodium (Na), carbon (C), magnesium (Mg), manganese (Mn), iron (Fe), phosphorus (P), zinc (Zn), and percentage of ash, extractives, cellulose and lignin.Results: Terminalia arjuna showed highest mass loss, while the lowest was observed in Shorea robusta showing significant positive correlation with litter initial K, Mg, Fe and di-O-alkyl C, O-alkyl C, while significant negative correlation with Mn, lignin and Methoxyl C, Alkyl C. Trajectories shows that Fe, Mg, K, Mn, Zn and Na concentrations increased in most of the litter types, except Terminalia arjuna and Toona ciliata, where Fe, Mg, K concentrations decreased during decomposition. Surprisingly, in most of the species with the exception of Terminalia arjuna, N concentrations decreased at a faster rate than C concentrations, resulting in an increase in C/N ratios. Expectedly, lignin progressively increased, while cellulose decreased.Conclusions: Observed differences in decomposition rate and dynamics of chemical changes among litters were strongly affected by the litter type, decomposition time and their interactions. [ABSTRACT FROM AUTHOR]