Leaf Stoichiometry of Halophyte Shrubs and Its Relationship with Soil Factors in the Xinjiang Desert

Abstract

Desert halophytes are a special plant group widely distributed in desert ecosystems. Studying their ecological stoichiometric characteristics is helpful for understanding their nutrient utilization characteristics and survival strategies. In this study, three functional groups of halophyte shrubs (euhalophytes, pseudohalophytes, and secretohalophytes) were studied in the Xinjiang desert, and the ecological stoichiometric characteristics of their leaves and their relationships with soil factors were evaluated. The results showed that the C content in secretohalophytes (442.27 ± 3.08 mg g−1) was significantly higher than that in the other functional groups (p < 0.05). The N and P contents in euhalophytes (22.17 ± 0.49 mg g−1 and 1.35 ± 0.04 mg g−1, respectively) were significantly higher than those in halophytes (p < 0.05). The N/P results showed that the growth rates of euhalophytes and pseudohalophytes were more susceptible to P limitation, whereas that of secretohalophytes was more susceptible to both N and P limitations, indicating that there were differences in nutrient characteristics among different functional groups. The results of the redundancy analysis showed that the leaf C, N, and P contents of euhalophytes were most affected by electrical conductivity (EC), whereas those of pseudohalophytes and secretohalophytes were most affected by the soil C content, indicating that different functional groups of halophyte shrubs had different responses to soil factors. The results of this study revealed the nutrient utilization characteristics of different functional groups of halophyte shrubs in the Xinjiang desert and their response and adaptation mechanisms to soil factors, thereby providing a basis for desert ecosystem management.