Abstract: Soil nutrient deficiency is one of the main factors limiting plant biomass in saline-alkali land. Chenopodiaceae is a dominant group in saline-alkali land. In this study, four Chenopodiaceae species, Suaeda glauca, Chenopodium acuminatum, Salsola tragus, and Bassia dasyphylla, were selected to evaluate the difference of quantitative characteristics of habitat soil factors and seven elements in different organs, aiming to clarify plant stoichiometry and its relationship with soil nutrients in saline-alkali ecosystems. The results showed that: (1) Soil Na content and soil electronic conductivity of S. glauca population were significantly higher than that of the other three species. Soil N content in S. tragus population was the lowest, while soil P content was the lowest in B. dasyphylla population. (2) Foliar C/N was in an order of S. glauca>S. tragus>C. acuminatum>B. dasyphylla. Root C/P of C. acuminatum was significantly higher than that of the other three species. Foliar N/P was more than 16 and root N/P was less than 14 in all species except C. acuminatum. (3) The K contents in all organs were significantly higher in B. dasyphylla. The Ca contents in leaves and roots were significantly higher in S. tragus. The Na contents in all organs were significantly higher in S. glauca. Mg contents in leaves and roots were significantly higher in B. dasyphylla. (4) The N enrichment coefficients and Ca enrichment coefficients in all organs were significantly higher in S. tragus. The P enrichment coefficients and K enrichment coefficients in leaves, stems and roots were significantly higher in B. dasyphylla. The Na enrichment coefficients in all organs were significantly higher in S. glauca. Our results indicated that N use efficiency was the highest in S. glauca, P use efficiency in roots was the highest in C. acuminatum, S. glauca had the strongest ability to absorb Na from soil, B. dasyphylla had the strongest ability to absorb P and K from soil, and S. tragus had the strongest ability to absorb N and Ca from soil.

Key words: saline-alkali land, Chenopodiaceae, nutrient element, ecological stoichiometry.