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Sand-binding vegetation is effective in stabilizing sand dunes and reducing soil erosion, thus helps minimize the detrimental effects of desertification. The aim of this study is to better understand the relationships between water and nutrient usage of sand-binding species, and the effects of succession and rainfall variability on plants’ water-nutrient interactions. We examined the effects of long-term succession (50 years), inter-annual rainfall variability (from 65% of the mean annual precipitation in 2004 to 42% in 2005) and seasonality on water-nutrient interactions of three major sand-binding species (Artemisia ordosica, Hedysarum scoparium and Caragana korshinskii) by measuring foliar delta C-13, delta N-15 and [N]. Long-term succession in general did not significantly alter delta C-13, delta N-15 and [N] of the three species. Short-term rainfall variability, however, significantly increased foliar delta C-13 levels of all three species by 1.0-1.8% during the severely dry year. No significant seasonal patterns were found in foliar delta C-13 and delta N-15 values of the three species, whereas foliar [N] varied by season. For the two leguminous shrubs, the correlations between delta C-13 and delta N-15 were positive in both sampling years, and the positive correlation between [N] and delta C-13 was only found in the severely dry year. The results indicate that these sand-binding plants have developed into a relatively stable stage and they are able to regulate their nitrogen and water use in responding to environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in degraded areas. However, the results also indicate that short-term climate variability could have severe impact on the vegetation functions. (C) 2013 Elsevier B. V. All rights reserved.