Abstract:Based on a 12year simulated warming and nitrogen(N)addition experiment, we explored the effects of warming and N addition on nutrient resorption for two common species, C3 plant Convolvulus ammannii and C4 plant Kochia prostrata, in 2016 with 52% above the longterm mean precipitation and in 2017 with 16% below the longterm mean. Plant N and phosphorus(P)contents, and resorption efficiencies were measured and analyzed. The results showed that: (1) in the wet year (2016), warming led to increases of 14.32% in green leaf N, 25.45% in senesced leaf N, 17.97% in green leaf P, 46.47% in senesced leaf P, and the N and P resorption efficiency significantly decreased by 9.41% and 16.99% (P < 0.05). N addition enhanced N contents in green and senesced leaves by 17.32% and 25.62%, and P contents in green and senesced leaves by 20.21% and 51.41%, but it significantly reduced N and P resorption efficiency by 9.33% and 18.89%(P < 0.05). Combined warming and N addition increased leaf N and P contents, and decreased resorption efficiency. (2) In the dry year (2017), warming and N addition, had no significant effect on these plant nutrient characteristics. (3) Significant differences in leaf N and P contents were found between the two species, and those of resorption efficiency were not observed. (4) Regression analysis indicated that N and P concentrations in plant leaves increased with soil N, P and water availability, while the resorption efficiency of plant N and P decreased with soil N, P and water availability. Research showed that the responses of nutrient resorption to warming and N addition could be mediated by variations of natural precipitation in a desert steppe.