Ali Hamada E, Al-Wahaibi Ahmed M, Shahid Muhammad Shafiq
Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman.
Life Science Unit, College of Science, Sultan Qaboos University, Muscat, Oman.
Front Plant Sci. 2024 Jan 16;15:1321950. doi: 10.3389/fpls.2024.1321950. eCollection 2024.
Invasive species have been identified as a major threat to native biodiversity and ecosystem functioning worldwide due to their superiority in spread and growth. Such superiority is explained by the invasional meltdown phenomena, which suggests that invasive species facilitate the establishment of more invasive species rather than native species by modifying the plant-soil feedback (PSF).
We conducted a two-phase plant-soil feedback experiment using the native Prosopis cineraria and the invasive Prosopis juliflora in Oman. Firstly, we conditioned the soil by planting seedlings of native species, invasive species, native and invasive species "mixed", and unconditioned soil served as a control. Secondly, we tested the feedback of these four conditioned soil on the two species separately by measuring the productivity (total biomass) and the performance in the form of plant functional traits (plant height, specific leaf area (SLA), leaf nitrogen content (Nmass), leaf carbon content (Cmass) and specific root length (SRL) of native and invasive species as well as the nutrient availability in soil (soil organic carbon (SOC) and soil total nitrogen (STN)).
We found that the native species produced more biomass, best performance, and higher SOC and STN when grown in soil conditioned by native species, additionally, it gave lower biomass, reduced performance, and lower SOC and STN when grown in the soil conditioned by invasive and mixed species. These results suggest negative PSF for native species and positive PSF for invasive species in the soil conditioned by invasive species, which can be considered as red flag concerning the restoration of as an important native species in Oman, as such positive PSF of the invasive species will inhibit the regeneration of .
由于入侵物种在传播和生长方面具有优势，它们已被确定为全球范围内对本地生物多样性和生态系统功能的主要威胁。这种优势可以通过入侵崩溃现象来解释，该现象表明入侵物种通过改变植物-土壤反馈（PSF）来促进更多入侵物种而非本地物种的建立。
我们在阿曼使用本地的灰叶豆（Prosopis cineraria）和入侵的牧豆树（Prosopis juliflora）进行了两阶段的植物-土壤反馈实验。首先，我们通过种植本地物种、入侵物种、本地和入侵物种“混合”的幼苗来处理土壤，未处理的土壤作为对照。其次，我们通过测量本地和入侵物种的生产力（总生物量）以及以植物功能性状（株高、比叶面积（SLA）、叶片氮含量（Nmass）、叶片碳含量（Cmass）和比根长（SRL））形式表现的性能，以及土壤中的养分有效性（土壤有机碳（SOC）和土壤总氮（STN）），分别测试这四种处理过的土壤对这两个物种的反馈。
我们发现，本地物种在由本地物种处理过的土壤中生长时产生更多生物量、表现最佳且SOC和STN更高，此外，当在由入侵物种和混合物种处理过的土壤中生长时，其生物量较低、表现降低且SOC和STN较低。这些结果表明，在由入侵物种处理过的土壤中，本地物种的PSF为负，入侵物种的PSF为正，这对于阿曼一种重要的本地物种[此处原文缺失物种名]的恢复而言可能是一个警示信号，因为入侵物种的这种正PSF将抑制[此处原文缺失物种名]的再生。
