J Plant Ecol ›› 2022, Vol. 15 ›› Issue (3): 509-523 .DOI: 10.1093/jpe/rtab073

• Research Articles • Previous Articles     Next Articles

Substrate availability regulates the suppressive effects of Canada goldenrod invasion on soil respiration

Zhiyuan Hu1,†, Jiaqi Zhang2,†, Yizhou Du3, Kangwei Shi1, Guangqian Ren1, Babar Iqbal1, Zhicong Dai1, Jian Li1, Guanlin Li1,* and Daolin Du1,*   

  1. 1 School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China, 2 Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences, Hainan Normal University, Haikou 571158, China, 3 School of Computer Science, Faculty of Engineering, University of Sydney, Sydney, NSW 2006, Australia

    * Corresponding author. E-mail: liguanlin@ujs.edu.cn (G.L.); ddl@ujs.edu.cn (D.D.)
    These authors contributed equally to this work.
  • Received:2021-02-13 Revised:2021-04-27 Accepted:2021-06-14 Online:2021-07-08 Published:2022-06-01

Abstract: Invasive alien plants not only decrease riparian vegetation diversity but also alter wetland ecosystem carbon processes, especially when they displace the original vegetation. Invasive Canada goldenrod (Solidago canadensis L.) has colonized large areas of disturbed and undisturbed land in southeastern China, yet little is known regarding how it affects soil carbon cycling. To explore the response patterns of soil respiration following S. canadensis invasion and their driving mechanisms, an observational field study and a greenhouse experiment simulating invasion were performed. In the field study, soil respiration was measured weekly from 21th July 2018 to 15th December 2018. In the greenhouse experiment, soil, autotrophic and heterotrophic respiration were measured every 1st and 15th of the month from 15th July 2019 to 15th December 2019. Soil, autotrophic and heterotrophic respiration were measured using a closed-chamber system with the deep gauze collar root exclusion method. Solidago canadensis invasion appeared to decrease the total soil CO2 emissions in both the field study and the greenhouse experiment. The suppressive effects on soil respiration may be attributed to S. canadensis invasion-induced alterations in the quality and quantity of available soil substrate, suggesting that S. canadensis invasion may impact soil carbon cycling via plant-released substrates and by competing for the soil available substrate with native plant and/or soil microbes. These results have substantial implications for estimations of the effects of invasive plants on belowground carbon dynamics and their contribution to the warming world.

Key words: Phragmites australis (Cav.) Trin. ex Steud, soil CO2 emission, soil substrate availability, competition, carbon cycling

外来植物入侵不仅会降低河边近岸湿地生态系统植被多样性,而且会改变湿地生态系统的地下碳过程。外来入侵植物加拿大一枝黄花(Solidago canadensis L.)已广泛入侵我国东南部地区,但加拿大一枝黄花入侵对入侵地生态系统地下土壤碳循环过程的影响却知之甚少。本研究通过野外原位观测实验和温室模拟入侵实验,探究外来植物加拿大一枝黄花入侵对入侵地土壤呼吸的影响规律及其驱动因素。野 外原位观测实验开展于2018年7月21日至12月15日,期间每周测定样地土壤呼吸。温室模拟入侵实验开展于2019年7月15日至12月15日,期间每月1日与15日上午测定土壤呼吸、自养呼吸和异养呼吸。土壤呼吸、自养呼吸和异养呼吸通过静态箱结合深埋根系隔离法测定。野外原位观测实验和温室模拟入侵实验结果均显示,加拿大一枝黄花的入侵降低了土壤二氧化碳的排放通量。加拿大一枝黄花入侵对土壤呼吸的抑制作用可能归因于其入侵引起的土壤可利用底物质量与数量的变化,表明外来入侵植物加拿大一枝黄花可通过改变植物释放基质以及与本地植物和/或土壤微生物争夺土壤有效基质而影响土壤碳循环。这些研究结果对于评估外来入侵植物对入侵地地下碳动态的影响以及对全球变暖的贡献具有重要意义。

关键词: 加拿大一枝黄花(Solidago canadensis L.), 芦苇(Phragmites australis (Cav.) Trin. ex Steud), 土壤二氧化碳排放通量, 土壤底物有效性, 竞争, 碳循环