Decomposition and nutrient dynamics of stumps and coarse roots of Eucalyptus plantations in southern China

<strong><em>Key message</em></strong>: <strong>Primary</strong><strong> remains of </strong><strong><em>Eucalyptus </em></strong><strong>(</strong><strong><em>E. urophylla × E. grandis</em></strong><strong>) </strong><strong>plantations</strong><strong> following clear-cutting are the stumps and coarse roots. </strong><strong>A chrono-sequence approach revealed that </strong><strong>the biomass of coarse roots is higher than that of stumps</strong><strong>,</strong><strong> while </strong><strong>they </strong><strong>ha</strong><strong>ve</strong><strong> a smaller rate of biomass loss than stumps. T</strong><strong>his</strong><strong> implies that coarse roots serve as long-term </strong><strong>stock</strong><strong> for</strong> <strong>nutrient</strong><strong>s</strong><strong> (</strong><strong>carbon, nitrogen</strong><strong>, and </strong><strong>p</strong><strong>hosphorus).</strong> <strong><em>C</em></strong><strong><em>ontext:</em></strong> A significant quantity of stumps and coarse roots persist in the forest floor following the clear-cutting of <em>Eucalyptus</em> plantations in China. The decomposition of these stumps and coarse roots is a crucial aspect of the nutrient stocks in plantations ecosystems. <strong><em>A</em></strong><strong><em>ims:</em></strong> We described the stock and decomposition dynamics of stumps and coarse roots on <em>Eucalyptus</em> plantations, as well as the nutrient loss rate associated with them. <strong><em>Methods:</em></strong> We used a chrono-sequence of 0–6-year-old clear-cutting stands of <em>Eucalyptus</em> plantations in southern China. The biomass and nutrient stocks of these samples were assessed at different times of decomposition. <strong><em>Results:</em></strong> The highest biomass of stump-root system was 33.8 Mg·ha^-1, with nutrient stocks were 16.3 Mg·ha^-1, and 63.0 kg·ha^-1, and 6710.9 g·ha^-1, for C, N, and P. The coarse roots accounted for 81–96% of the biomass of the stump-root system. The loss rate of biomass and nutrients from stumps was higher than that of coarse roots. This suggests that the decomposition of coarse roots could serve as a long-term source of nutrients, thereby improving the nutrient status of the plantations. <strong><em>Conclusion:</em></strong> Stumps and coarse roots serve as significant nutrients stocks that decay at varying rates. The loss of nutrients must be considered while analyzing the decomposition dynamics following clear-cutting in <em>Eucalyptus</em> plantations. This dataset is related to a research paper submitted to Annals of Forest Science.