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Aims: Tree logging in tropical tree plantations results in significant soil disturbances that negatively impact soil biodiversity and soil functioning. Here, we aimed to assess the effects of adding organic matter (OM) to soil after rubber tree logging on soil functioning over time. Methods: The experiment was conducted in two contrasting soil types in Ivory Coast. Four practices were replicated, including a control with no residues, the presence of legumes only, legumes and all tree parts excluding the trunk, and legumes and all the parts of the tree including the trunk. We monitored the response of soil nematode communities every six months for 24 months in each practice. Samples were collected from the topsoil layer (0–10 cm) in the interrow, and we also monitored soil carbon transformation by measuring in situ basal soil respiration, labile soil carbon and organic matter decay using the bait lamina method. Results: The results showed a sharp decrease in nematode abundance after tree logging, but OM restoration increased nematode abundance, the relative abundance of bacterivores, and resource availability to the soil food web. The resilience of the nematode communities depended on soil conditions and the amount and quality of logging residues. Total nematode abundance was positively and significantly related to soil functioning, measured through basal soil respiration, labile soil carbon, and organic matter decay rate. Conclusion: The results suggest that restoring logging residues can be an effective way to restore soil biodiversity and mitigate the negative impact of clear-cutting in tropical rubber plantations. [ABSTRACT FROM AUTHOR]

The rapid expansion of rubber tree plantations in recent decades has been accompanied by dramatic negative ecological and social impacts. Rubber sector stakeholders consequently engaged in sustainable production of rubber. Despite the lack of harvest during the immature stage following planting, this period plays a key role in future yields. Management practices, particularly fertilization regimes, are used by farmers to shorten the immature period as much as possible. This entails maintaining or even improving the productivity of existing plantations to face the demand for natural rubber. This review focuses specifically on the immature period of rubber tree plantations, as it is the most critical period for nutrient management. We reviewed available knowledge on fertilization practices, soil management, and nutrient dynamics in rubber plantations with the goal of developing a nutrient balance approach for this crop. Our review revealed (1) a notable difference between fertilizer recommendations made by technical institutes and those reported in the scientific literature; (2) that even though nutrient diagnostic methods could help growers adapt the fertilization of rubber trees more than 3 years of age, further studies are needed to adapt current methods to the wide range of cultivation areas; and (3) that the nutrient budget approach may be the best way to incorporate the variety of rubber tree cultivation conditions. In conclusion, the nutrient budget method is a promising way to improve the sustainability of rubber plantations through fertilization making it possible to increase nutrient use efficiency. A comprehensive approach based on nutrient budgets requires further in-depth studies to examine nutrient dynamics in a wide range of conditions, including intercropping and logging residue management between clearcutting and replanting. [ABSTRACT FROM AUTHOR]