干旱区研究 ›› 2022, Vol. 39 ›› Issue (4): 1181-1190.doi: 10.13866/j.azr.2022.04.19

• 土壤生态 • 上一篇    下一篇

荒漠灌丛土壤酶活性对UV-B辐射及凋落物分解的响应

韦昌林(),李毅(),单立山,解婷婷   

  1. 甘肃农业大学林学院,甘肃 兰州 730070
  • 收稿日期:2021-09-07 修回日期:2022-03-18 出版日期:2022-07-15 发布日期:2022-09-26
  • 通讯作者: 李毅
  • 作者简介:韦昌林(1998-),女,硕士研究生,主要从事干旱区植物生理生态研究. E-mail: 2603572411@qq.com
  • 基金资助:
    国家自然科学基金项目(31960245);国家自然科学基金项目(32160253);甘肃农业大学公招博士科研启动基金项目(GAU-KYQD-2018-07);对发展中国家科技援助项目(KY202002011)

Desert shrub soil enzyme activity of UV-B radiation and litter decomposition response

WEI Changlin(),LI Yi(),SHAN Lishan,XIE Tingting   

  1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2021-09-07 Revised:2022-03-18 Online:2022-07-15 Published:2022-09-26
  • Contact: Yi LI

摘要:

探究土壤酶活性对UV-B辐射和不同凋落物分解的响应对揭示凋落物周转及土壤养分动态具有重要意义。采用模拟UV-B辐射滤减(聚脂薄膜法)和分解袋法,研究了UV-B辐射变化对西北干旱荒漠区典型灌丛红砂和珍珠以及二者的混合凋落物层下土壤酶活性的影响。结果表明:(1) 辐射滤减提高了不同凋落物土壤脲酶和碱性磷酸酶活性,且对珍珠灌丛土壤酶活性的促进作用更明显,不同土层(0~5 cm和5~15 cm)分别增加了45.45%、58.28%和39.04%、117.65%;然而,辐射滤减降低了不同凋落物土壤多酚氧化酶和木质素过氧化物酶活性,同样对珍珠灌丛土壤酶活性的抑制效应更明显,不同土层分别减少了36.69%、39.52%和59.78%、43.63%;辐射滤减对土壤纤维素酶活性无明显效应。(2) 在辐射滤减和自然光照条件下,混合凋落物土壤多酚氧化酶活性均小于单一凋落物,说明混合凋落物土壤中有机质的腐殖化程度大于有机质的积累,土壤腐殖化程度更高。(3) 不同类型凋落物对表层土壤(0~5 cm)酶活性的影响更为明显;随着土层加深,各类型下土壤脲酶和磷酸酶活性均降低,多酚氧化酶活性增加。

关键词: UV-B辐射, 凋落物, 干旱荒漠, 土壤酶

Abstract:

Exploring the response of soil enzyme activity to UV-B radiation and decomposition of different litters is crucial for revealing litter turnover and soil nutrient dynamics. The effects of UV-B radiation on soil enzyme activities of litters of Reaumuria soongarica and Salsola passerina and their mixture were studied by using simulated UV-B radiation filtration (mylar film method) and decomposition bag method. The following results are presented. (1) Radiation filtration increased the soil urease and alkaline phosphatase activities of different litters and promoted the soil enzyme activities of S. passerina shrub significantly, which increased by 45.45%, 58.28% and 39.04%, 117.65% in different soil layers (0-5 cm and 5-15 cm), respectively. The radiation filter minimizes the different litter reductions. However, soil polyphenol oxidase and peroxidase activities of lignin, which are the same soil enzyme activity of S. passerina thickets of inhibition effect, are observed in different soil reductions by 36.69%, 39.52% and 59.78%, 43.63%, respectively. Radiation filtration did not affect on soil cellulase activity. (2) Under radiation filtration and natural light conditions, the activity of polyphenol oxidase in the soil of mixed litters was lower than that of single litters, indicating that the degree of organic matter humification in the soil of mixed litters was larger than that of organic matter accumulation, and the degree of soil humification was high. (3) The effects of different litters on the enzyme activities of surface soil (0-5 cm) were observed. Soil urease and phosphatase activities decreased and polyphenol oxidase activities increased with the deepening of the soil layer.

Key words: UV-B radiation, litter, arid desert, soil enzyme