Ectomycorrhizal trees rely on nitrogen resorption less than arbuscular mycorrhizal trees globally

<p>Nitrogen (N) resorption is an important pathway of N conservation, contributing to a proportion of plant N requirement.&nbsp;However, whether the ratio of N resorption to N requirement would be affected by environmental factors, mycorrhizal types or atmospheric CO2 concentration remains unclear. Here, we conducted a meta-analysis on the impacts of environmental factors and mycorrhizal types on this ratio.&nbsp;We found this ratio in ectomycorrhizal (EM) trees decreased with mean annual precipitation (MAP), mean annual temperature (MAT), soil total N content (TN) and atmospheric CO2 concentration&nbsp;and was significantly lower than that in arbuscular mycorrhizal (AM) trees. An <i>in situ</i> 15N tracing&nbsp;experiment further confirmed this stronger reliance on N resorption for AM trees than EM trees. Our study suggests that AM and EM trees potentially have different strategies for alleviation of progressive N limitation, highlighting the necessity of incorporating plant mycorrhizal types into Earth System Models.&nbsp;</p>