Crespo Daniel, Solan Martin, Leston Sara, Pardal Miguel A, Dolbeth Marina
Department of Life Sciences Centre for Functional Ecology-CFE University of Coimbra Coimbra Portugal.
Ocean and Earth Science National Oceanography Centre Southampton University of Southampton Southampton UK.
Ecol Evol. 2018 Jan 11;8(3):1807-1817. doi: 10.1002/ece3.3652. eCollection 2018 Feb.
The freshwater-marine transition that characterizes an estuarine system can provide multiple entry options for invading species, yet the relative importance of this gradient in determining the functional contribution of invading species has received little attention. The ecological consequences of species invasion are routinely evaluated within a freshwater versus marine context, even though many invasive species can inhabit a wide range of salinities. We investigate the functional consequences of different sizes of -an invasive species able to adapt to a wide range of temperatures and salinity-across the freshwater-marine transition in the presence versus absence of warming. Specifically, we characterize how affect fluid and particle transport, important processes in mediating nutrient cycling (NH -N, NO -N, PO -P). Results showed that sediment particle reworking (bioturbation) tends to be influenced by size and to a lesser extent, temperature and salinity; nutrient concentrations are influenced by different interactions between all variables (salinity, temperature, and size class). Our findings demonstrate the highly context-dependent nature of the ecosystem consequences of invasion and highlight the potential for species to simultaneously occupy multiple components of an ecosystem. Recognizing of this aspect of invasibility is fundamental to management and conservation efforts, particularly as freshwater and marine systems tend to be compartmentalized rather than be treated as a contiguous unit. We conclude that more comprehensive appreciation of the distribution of invasive species across adjacent habitats and different seasons is urgently needed to allow the true extent of biological introductions, and their ecological consequences, to be fully realized.
河口系统所具有的淡水 - 海洋过渡特征可为入侵物种提供多种进入途径，然而这一梯度在决定入侵物种功能贡献方面的相对重要性却很少受到关注。尽管许多入侵物种能够栖息在广泛的盐度范围内，但物种入侵的生态后果通常是在淡水与海洋的背景下进行常规评估的。我们研究了在有变暖与无变暖情况下，一种能够适应广泛温度和盐度的入侵物种在淡水 - 海洋过渡带不同大小的功能后果。具体而言，我们描述了其如何影响流体和颗粒传输，而流体和颗粒传输是介导营养物质循环（NH₄⁺ - N、NO₃⁻ - N、PO₄³⁻ - P）的重要过程。结果表明，沉积物颗粒重塑（生物扰动）往往受大小影响，在较小程度上受温度和盐度影响；营养物质浓度受所有变量（盐度、温度和大小类别）之间不同相互作用的影响。我们的研究结果表明入侵对生态系统造成的后果具有高度的情境依赖性，并强调了物种同时占据生态系统多个组成部分的可能性。认识到入侵性的这一方面对于管理和保护工作至关重要，特别是因为淡水和海洋系统往往被划分开来，而不是被视为一个连续的单元。我们得出结论，迫切需要更全面地了解入侵物种在相邻栖息地和不同季节的分布情况，以便充分认识生物引入的真实范围及其生态后果。
