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草业学报 ›› 2023, Vol. 32 ›› Issue (10): 15-27.DOI: 10.11686/cyxb2022469

• 研究论文 • 上一篇    下一篇

土壤有机磷矿化特征对高寒草甸退化及温度的响应

钱虹宇(), 蒲玉琳(), 郎山鑫, 李怡燃, 周南丁   

  1. 四川农业大学资源学院,四川 成都 611130
  • 收稿日期:2022-11-29 修回日期:2023-02-27 出版日期:2023-10-20 发布日期:2023-07-26
  • 通讯作者: 蒲玉琳
  • 作者简介:E-mail: pyulin@sicau.edu.cn
    钱虹宇(1995-),男,四川富顺人,硕士。E-mail: qhy1632021@163.com
  • 基金资助:
    四川省科学技术厅应用基础研究项目(2021YJ0341)

Response of soil organic phosphorus mineralization to alpine meadow degradation and temperature

Hong-yu QIAN(), Yu-lin PU(), Shan-xin LANG, Yi-ran LI, Nan-ding ZHOU   

  1. College of Resources,Sichuan Agricultural University,Chengdu 611130,China
  • Received:2022-11-29 Revised:2023-02-27 Online:2023-10-20 Published:2023-07-26
  • Contact: Yu-lin PU

摘要:

明晰退化草地土壤有机磷在不同温度下的矿化特征,可为退化草地生态恢复中的土壤磷养分科学调控提供基础数据与理论依据。采用恒温控湿好气培养法研究若尔盖高原未退化草甸(ND)、轻度退化(LD)、中度退化(MD)、重度退化(HD)草甸土壤有机磷矿化特征及温度效应。结果表明,4类草甸土壤5~15 ℃培养下,有机磷矿化速率在前期(0~30 d)无明显变化,中期(30~60 d)快速增加,后期(60~120 d)逐渐趋于稳定。低温(5~10 ℃)时,草甸退化对土壤有机磷矿化无显著影响,但在高温(≥15 ℃)时,草甸自中度退化开始显著降低了土壤有机磷矿化作用。与ND相比,15 ℃时MD和HD土壤有机磷净矿化速率分别显著降低52.8%、56.8%,表征土壤有机磷矿化快慢常数的B0 值分别显著降低29.5%、40.4%。土壤有机磷矿化的温度敏感性随草甸退化程度加剧而逐渐降低,ND土壤有机磷矿化的温度敏感系数y″值分别比MD、HD显著升高221.1%、306.7%。由此可见,高寒草甸退化减小了土壤有机磷的矿化作用和温度敏感性,进而降低了土壤磷素有效性,还可能因全球继续变暖而诱发退化草地生态系统的磷限制问题。

关键词: 若尔盖高原, 草甸退化, 土壤有机磷矿化, 温度敏感性

Abstract:

Clarification of the mineralization characteristics of organic phosphorus in degraded grassland soils at different temperatures can provide basic data and a theoretical framework for the scientific management of soil phosphorus nutrients during the ecological recovery of degraded grassland. In this research, an aerobic culture method at constant temperature and humidity was used to investigate the mineralization characteristics and temperature responses of organic phosphorus in non-degraded (ND) meadow, and lightly degraded (LD), moderately degraded (MD) and heavily degraded (HD) soils on the Zoige Plateau. It was found that the mineralization rate of organic phosphorus showed no obvious change in the early stage (0-30 d), increased rapidly in the middle stage (30-60 d), and gradually stabilized in the late stage (60-120 d) when the four types of meadow soils were cultured at 5-15 ℃. Meadow degradation had no significant effect on soil organic phosphorus mineralization at low temperature (5-10 ℃). However, soil organic phosphorus mineralization was significantly reduced in MD and HD soils at high temperature (≥15 ℃). Compared with ND, the net mineralization rate of organic phosphorus in MD and HD soils decreased by 52.8% and 56.8%, respectively, at 15 ℃, and the constant B0 of soil organic phosphorus mineralization decreased by 29.5% and 40.4%, respectively. Furthermore, the temperature sensitivity of soil organic phosphorus mineralization decreased gradually with increased severity of meadow degradation. For example, the temperature sensitivity coefficient y" of organic phosphorus mineralization in ND soil was significantly higher than that in MD and HD soils by 221.1% and 306.7%, respectively. In summary, the degradation of alpine meadow reduced the mineralization and temperature sensitivity of soil organic phosphorus, which would be predicted to result in further reduction of soil phosphorus availability, and exacerbate any problem of phosphorus limitation in degraded grassland ecosystems arising from ongoing global warming.

Key words: Zoige Plateau, meadow degradation, soil organic phosphorus mineralization, temperature sensitivity