Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China.
College of Life Science, Shaanxi Key Laboratory of Ecological Restoration in Northern Shaanxi Mining Area, Yulin University, Yulin 719000, China.
Sci Total Environ. 2024 Nov 15;951:175591. doi: 10.1016/j.scitotenv.2024.175591. Epub 2024 Aug 20.
Nitrogen (N) in the atmosphere frequently affects plant growth, ecological stoichiometric equilibrium, and homeostasis stability. However, the effect of N addition application on the growth of Hippophae rhamnoides seedlings remains ambiguous. We investigated the effects of N addition on the ecological stoichiometry and homeostatic characteristics of H. rhamnoides seedlings. Greenhouse cultivation experiments were conducted at five N application levels: 0 kg ha yr(CK), 100 kg ha yr (N10), 200 kg ha yr (N20), 400 kg ha yr (N40), 800 kg ha yr (N80). The results showed that pH and available phosphorus (AP) significantly decreased with increasing N, whereas soil C:P and N:P ratios significantly increased under the N40 and N80 treatments. The leaf C:N ratio significantly decreased with increasing N, whereas the N:P ratio increased. With N addition, the C:N ratio of plant stems and roots significantly decreased, whereas the C:P and N:P ratios significantly increased. N addition was significantly correlated with the ecological stoichiometry of plant leaves and soil properties (0.38 and 0.84, respectively). Homeostasis of the organs of H. rhamnoides seedlings exhibited an absolute steady state. The C, N, and C:P ratios of the roots exhibited insensitive states under the N40 treatment. N addition significantly modified both the soil ecological stoichiometry and the stoichiometry of H. rhamnoides seedlings. However, it did not demonstrate a pronounced negative effect on the homeostasis of H. rhamnoides seedlings. This study offers new insights into the ecological adaptation process of H. rhamnoides, particularly concerning its nutrient distribution, utilization strategies, and stability.
大气中的氮（N）经常影响植物的生长、生态化学计量平衡和内稳态稳定性。然而，N 添加应用对沙棘幼苗生长的影响仍不明确。我们研究了 N 添加对沙棘幼苗生态化学计量和内稳态特征的影响。在五个 N 添加水平（0 kg ha yr（CK）、100 kg ha yr（N10）、200 kg ha yr（N20）、400 kg ha yr（N40）和 800 kg ha yr（N80））下进行了温室栽培实验。结果表明，随着 N 的增加，pH 值和有效磷（AP）显著降低，而在 N40 和 N80 处理下，土壤 C：P 和 N：P 比值显著增加。叶片 C：N 比随着 N 的增加而显著降低，而 N：P 比增加。随着 N 添加，植物茎和根的 C：N 比显著降低，而 C：P 和 N：P 比显著增加。N 添加与植物叶片和土壤性质的生态化学计量显著相关（分别为 0.38 和 0.84）。沙棘幼苗器官的内稳态表现出绝对稳态。在 N40 处理下，根的 C、N 和 C：P 比表现出不敏感状态。N 添加显著改变了土壤生态化学计量和沙棘幼苗的化学计量。然而，它并没有对沙棘幼苗的内稳态表现出明显的负面影响。本研究为沙棘的生态适应过程提供了新的见解，特别是关于其养分分布、利用策略和稳定性。
