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Abstract

Based on litter mass and litterfall data, decomposition rates for leaves were found to be fast (k = 3.3) and the turnover times short (3.6 mo) on the low-nutrient sandy soils of Korup. Leaf litter of four ectomycorrhizal tree species (Berlinia bracteosa, Didelotia africana, Microberlinia bisulcata and Tetraberlinia bifoliolata) and of three non-ectomycorrhizal species (Cola verticillata, Oubanguia alata and Strephonema pseudocola) from Korup were left to decompose in 2-mm mesh bags on the forest floor in three plots of each of two forest types forest of low (LEM) and high (HEM) abundance of ectomycorrhizal (caesalp) trees. The litter of the ectomycorrhizal species decayed at a significantly slower rate than that of the non-ectomycorrhizal species, although the former were richer in P and N concentrations of the start. Disappearance rates of the litter layer showed a similar trend. Ectomycorrhizal species immobilized less N, but mineralized more P, than non-ectomycorrhizal species. Differences between species groups in K, Mg and Ca mineralization were negligible. Effect of forest type was clear only for Mg: mineralization of Mg was faster in the HEM than LEM plots, a pattern repeated across all species. This difference was attributed to a much more prolific fine root mat in the HEM than LEM forest. The relatively fast release of P from the litter of the ectomycorrhizal species suggests that the mat must allow an efficient uptake to maintain P in the forest ecosystem.

Average leaf litter quality drives the decomposition of single-species, mixed-species and transplanted leaf litters for two contrasting tropical forest types in the Congo Basin (DRC)

“…Through its impact on carbon, nutrient and water cycles, litter decomposition is a central ecosystem process, at both global and local scales (Chapin et al 2011). Litter decomposition is determined by multiple key drivers including climate, litter quality, sitespecific factors (such as soil properties) and the decomposer community (Coûteaux et al 1995;Aerts 1997;Hättenschwiler et al 2005). Under similar conditions of macroclimate, topography and soil, the decomposition of litter is expected to first depend on its average quality, through the provision of resources, habitat and secondary, possibly inhibitory, compounds to the decomposers and detritivores.…”

“…Most studies addressing the drivers behind the variability in litter decomposition under tropical rainforests have been carried out in the Amazon Basin (Hättenschwiler et al 2011;Nottingham et al 2018;Oliveira et al 2019;Four et al 2019). Several decomposition studies have been conducted in Central Africa (Bernhard-Reversat and Schwartz 1997;Torti et al 2001;Chuyong et al 2002;Peh 2009;Peh et al 2012), yet we still have a limited understanding of the decomposition process and its drivers for major African rainforest types, especially in the Democratic Republic of the Congo.…”

Mast fruiting in a large tropical African legume tree provides evidence for the nutrient resource limitation hypothesis

“…Nevertheless, the main mineralization and uptake occurs in early weeks of the wet season (Chuyong et al 2002), and this would be similar each year once the water contents were high enough. This dryness then is thought to be a proxy for a mechanism that triggers translocation, but it is one that cannot operate without the previous year acquiring more P, and setting up a form of 'relay'.…”

“…Larger vertical roots are able to tap deeper water reserves. Nutrient cycling in the groves shows a 'fast-forward' modus: leaf litter decay is fast, there is no permanent leaf litter layer, and most cycling via the very efficient mat happens in the early wet season (Chuyong et al 2000(Chuyong et al , 2002. At this time throughfall nutrients help to prime decomposition and uptake (Chuyong et al 2004).…”

Dynamics and relationships of Ca, Mg, Fe in litter, soil fauna and soil in Pinus koraiensis-broadleaf mixed forest

“…Material cycle and release in the decomposition of detritus are very important to supply continuous primary production (Seastedt, 1984). Therefore, it is one of the popular topics in terrestrial ecosystem (Chuyong et al, 2002;Zhang et al, 2005;Liu et al, 2006;Barlow et al, 2007).…”