Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging from -9 to +26 °C MAT and from 60 to 3113 mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained <0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments). When the data were aggregated at the biome scale, climate played a significant role on decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea). No significant effect of land-use on early stage litter decomposition was noted within the temperate biome. Our results indicate that multiple drivers are affecting early stage litter mass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed.

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El presente trabajo muestra los posibles orígenes, el desarrollo y evolución de los diversos procesos de manufactura de las cadenas, trazando la línea base sobre la existencia de la cadena por miles de años, primeramente utilizada en sistemas de cangilones de agua y en bocetos de Leonardo da Vinci, evolucionando morfológicamente en función de las necesidad o posibilidades de cada taller de artesano, para dar paso con el devenir de los años a su apogeo en la industria marítima en el siglo XIX mediante mecanismos de manufactura por fundición o forja, paralelamente la revolu- ción industrial impulsó la sustitución de la fuerza del herrero por la de las máquinas, pudiendo implementar procesos de manufactura de cadenas soldadas cada vez de forma mas automática. Finalmente se concibe la cadena como un conjunto de eslabones en constante cambio ligado a los avances tecnológicos y necesidades de la historia de la humanidad.