Allometric relationships among different components of forest litterfall in China

Aims Litterfall is a measure of the metabolic product of forest plants during their growth. It plays an important part in the fluxes and recycling of matter and energy. The metabolic theory of ecology posits that there exist al- lometric relationships among different organs of a plant. However, all these scaling relationships do not take into account the potential contribution of litterfall, and hence much remains unknown about the allometric relation- ships among the different components of litterfall. In this study, we analyze the allometric relationships between component as well as the allometric relationships of the total litterfall with different components. Methods We compiled data on forest litterfall from the literature published in Chinese journals and divided these data into evergreen forests and deciduous forests for analysis of the allometric relationships between components as well as the allometric relationships of the total litterfall with different components.Important findings We found that the average amount of litterfall was 3 810.34 kg·hm–2·a–1, 1 019.07 kg·hm–2·a–1, and 767.95 kg·hm–2·a–1as leaves, branches, and propagules, respectively. Compared with precipita- tion and stand age, temperature had a greater effect on forest litterfall production. An isometrical relationship was observed between leaves and the total litterfall, as LL ∝ LT 0.96(LL, leaf litterfall; LT, total litterfall); whereas an allometric relationship was found between the propagules and the total litterfall as LP ∝ LT 1.84(LP, propagule lit- terfall), and between the branches and the total litterfall as LB ∝ LT 1.61(LB, branch litterfall), respectively. Signifi- cant allometric relationships were also observed among different components, with exponents all less than 1.0 in each case. Allometric relationships of the total litterfall with different components were approximately the same between the evergreen forests and the deciduous forests. The allometric relationships found in this study provide valuable insights into the investigation and estimation of forest productivity.