伊犁河谷苦豆子C、N、P含量变化及化学计量特征

研究苦豆子不同器官中碳、氮、磷元素的化学计量特征的季节变化有助于深入了解该植物蔓延的生态学机制。系统分析了伊犁河谷苦豆子根、茎、叶的碳(C)、氮(N)、磷(P)化学计量特征及其季节动态变化。结果表明∶苦豆子C、N、P含量均值分别为391.40、13.17、1.51mg/g,C∶N、N∶P、C∶P均值分别为45.61、8.52、326.38。苦豆子根、茎、叶在整个生长季内C、N、P均值含量变化一致,为叶茎根。在生态化学计量特征的分析中规律则不同,C含量随着生长时期的增加而增加,N和P的含量则随着生长时期的增加而减少;苦豆子根系中的C、N、P含量有随着深度变化而递减的趋势;器官间的差异性说明植物在不同生长时期,各器官对C、N、P的吸收利用具有特异性。植物叶片中C、N、P含量和N∶P普遍较低,苦豆子生长受N、P的共同限制,更容易受到N元素的限制。

The study of carbon, nitrogen, phosphorus content changes and their stoichiometry of Sophoraalopecuroides in the Yili River Region

To derive a deeper understanding of the ecological mechanism of the spread of Sophora alopecuroides, this study systematically analyzed C, N, and P stoichiometry and its seasonal dynamic changes in the roots, stems, and leaves of Sophora alopecuroides distributed in the Yili River Valley. The results showed average C, N, and P contents to be 391.40, 13.17, and 1.51 mg/g; the average ratios of C/N, N/P, and C/P were 45.61, 8.52, and 326.38, respectively. The changes of the mean C, N, and P content showed the same pattern in the roots, stems, and leaves of Sophora alopecuroides during the completely growing season; leaves contained most of the nutrients, followed by stems and roots. However, they exhibited different patterns in the stoichiometric analysis. The C content increased with increasing plant growth, while N and P content declined. The content of C, N, and P in the root system of Sophora alopecuroides had a tendency to decline with the change in depth. The differences between organs indicated that the absorption and utilization of C, N, and P were specific to the plants during different growth periods. Plant leaves tended to have low C, N, and P content and N/P ratio. The growth of Sophora alopecuroides was limited by N and P jointly, but will be easier to constrain by N elements.