Abstract: Leguminous species have an advantage in acquiring phosphorus (P) compared to non-leguminous species. Nonetheless, it remains unclear whether this advantage would diminish under long-term nitrogen (N) deposition. In the seventh year of a simulated long-term N deposition experiment, we sampled surface soil to measure acid phosphatase activity (ACP) in stands dominated by leguminous and non-leguminous species, respectively. To assess the response of ACP to prolonged N addition, we also collected data on ACP in the second, eighth, twelfth, and thirteenth years of the experiment.We found that the difference in soil ACP between the two plantation types disappeared after long-term N input, and this process was accelerated under high N addition. This occurs due to an exacerbated P-limitation, which primarily prompting ACP production merely in non-leguminous species. Additionaly, there is a relatively decreased N contribution efficiency to ACP in the stand with leguminous species, this indicates that soil N content no longer primarily governs ACP. This study demonstrates that prolonged high N deposition accelerates the loss of the “P-acquiring advantage” in leguminous plantations. To elucidate the differences in P usage strategies between leguminous and non leguminous species under global change, more systematic research is warranted in the future

Key words: P-acquiring advantage, N deposition, leguminous species, subtropical forest, P limitation