Qian Hongyu, Yang Nairui, Jiang Haodong, Li Yinan, Shen Ao, Hu Yufu
College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
Plants (Basel). 2025 May 10;14(10):1429. doi: 10.3390/plants14101429.
Phosphorus (P) is essential for plant growth, but its soil availability depends on the characteristics of P fractions. However, few studies have examined soil P fractions under ecological restoration in alpine and semi-humid regions. This study investigated three restoration methods on the eastern Tibetan Plateau: planting mixed grasses (MG), planting alone (SA), and planting in combination with grasses (SG), restored for 14 years, with untreated sandy land (CK) as control. Through field sampling and laboratory analysis, soil P fractions and physicochemical properties were analyzed. The findings demonstrate that the three ecological restoration modes could increase total P and total organic P content and reduce inorganic P content. Ecological restoration can improve the content of soil labile P (resin-Pi, NaHCO-Pi, and NaHCO-Po) by activating NaOH-Pi and HCl-P, thus improving the availability of soil P and increasing the potential P (residual-P) source. Soil P fractions content positively correlated with SWC, SOC, and TN ( < 0.05) but negatively with BD and pH ( < 0.05). The experimental outcomes of this study will help to understand the P availability and its potential sources during ecological restoration while providing a scientific foundation for selecting optimal restoration strategies in alpine sandy land.
磷（P）对植物生长至关重要，但其在土壤中的有效性取决于磷组分的特性。然而，很少有研究考察高寒半湿润地区生态恢复过程中的土壤磷组分。本研究在青藏高原东部调查了三种恢复方法：种植混合草（MG）、单独种植（SA）和与草结合种植（SG），恢复14年，以未处理的沙地（CK）作为对照。通过田间采样和实验室分析，对土壤磷组分和理化性质进行了分析。研究结果表明，三种生态恢复模式均可增加总磷和总有机磷含量，降低无机磷含量。生态恢复可通过活化NaOH-Pi和HCl-P来提高土壤活性磷（树脂-Pi、NaHCO-Pi和NaHCO-Po）含量，从而提高土壤磷的有效性，并增加潜在磷（残留-P）源。土壤磷组分含量与土壤含水量、土壤有机碳和全氮呈正相关（<0.05），与土壤容重和pH呈负相关（<0.05）。本研究的实验结果将有助于了解生态恢复过程中磷的有效性及其潜在来源，同时为高寒沙地选择最佳恢复策略提供科学依据。
