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The home-field advantage hypothesis predicts greater litter decomposition at home. However, this hypothesis repeatedly fails to account for site-specific variation in litter decomposition, particularly in hyper-diverse forests, suggesting the existence of other mechanisms. Alternatively, the plant apparency hypothesis, which originated from plant-herbivore interactions studies, posits that litter of dominant species decomposes more rapidly than that of rare species. We examined these two hypotheses in three tropical rainforests in Southwest China. Within each forest, we carried out reciprocal litter transplant experiments with litter sourced from dominant, common, and rare species by using two mesh sizes (0.15 mm and 2 mm) to control decomposer community composition access into the litterbag. Litter beneath dominant species decomposed more rapidly than that beneath rare species, regardless of the source. Moreover, litter of dominant species decomposed more rapidly than that of rare species. Plant apparency hypothesis occurred only in the coarse mesh, regardless of litter quality or soil nutrient condition, highlighting that soil fauna activity controlled the plant apparency hypothesis. This study extends the application of plant appearance hypothesis to litter decomposition process mediated by soil fauna mediate. This underscores the influence of the dominant tree species on soil fauna composition and thus nutrient cycling.

生境优势假说（home-field advantage hypothesis）预测枯落物在其起源生境中的分解速率更高。然而，该假说始终无法解释枯落物分解的生境特异性差异，尤其在超多样性森林中，这暗示了其他驱动机制的存在。另有植物可见性假说（plant apparency hypothesis），该假说起源于植物-草食动物互作研究，其核心假定为优势物种的枯落物分解速率快于稀有种枯落物。我们在中国西南部的三处热带雨林中对这两项假说进行了验证：在每处雨林内，我们选取优势种、常见种与稀有种的枯落物开展枯落物互置移植实验，通过设置两种网袋孔径（0.15 mm与2 mm）控制分解者群落对枯落物袋的准入范围。实验结果显示，无论枯落物的物种来源如何，放置在优势种冠层下的枯落物分解速率均快于放置在稀有种冠层下的枯落物；此外，优势种枯落物本身的分解速率也显著高于稀有种枯落物。植物可见性假说仅在粗孔径网袋处理中成立，且不受枯落物质量与土壤养分条件的影响，这表明土壤动物活动调控了植物可见性假说的效应。本研究将植物可见性假说的适用范围拓展至由土壤动物介导的枯落物分解过程，进一步凸显了优势树种对土壤动物群落组成的调控作用，进而影响土壤养分循环。