Department of Marine Sciences, University of South Alabama, LSCB 25, Mobile, AL, 36688, USA; Dauphin Island Sea Lab, 101 Bienville Boulevard, Dauphin Island, AL, 36528, USA.
Instituto de Investigaciones Marinas y Costeras (IIMyC). FCEyN. Universidad Nacional de Mar Del Plata-CONICET. CC 1260, Funes 3250, 7600, Mar Del Plata, Argentina.
J Environ Manage. 2022 Nov 1;321:116025. doi: 10.1016/j.jenvman.2022.116025. Epub 2022 Aug 24.
Human coastal occupation often leads to the degradation of the structural properties and environmental functions of natural coastlines. . Much research has been done on the cost-effectiveness of various living shorelines designs, however more work is needed for simple, small-scale designs that are typically adopted in waterfront residential or recreational properties. To contribute to this gap, we planted small-scale plots of black needlerush (Juncus roemerianus) in two sites, one in a residential property and another one in a recreational property in the Northern Gulf of Mexico that experienced significant wave energy. Plots were planted at two different densities (50% or 100% initial cover) or left unplanted (controls) and, along with monitoring the evolution of the planted salt marsh, we measured a number of functional metrics including soil slope, abundance of nekton within and in front of the plots, and cover of submerged aquatic vegetation (SAV) in front of the plots monthly over two years. In one of the sites plant cover decreased precipitously, and in the other site we did not observe any significant changes in plant cover over time (i.e. the initial 50% and 100% plantings remained at that level throughout the experiment) despite protecting the planted salt marsh with coir logs. We did not find any changes in soil slope or nekton abundance between planted and control plots. SAV growth was restrained in front of planted plots in relation to control plots, possibly due to deleterious impacts by the coir logs. Overall, the results suggest the protection against wave energy attained in this experiment is insufficient for adequate saltmarsh establishment and growth, thereby encountering decreasing or stationary plant density and no significant differences in soil slope or nekton abundance between planted and non-planted plots. Our results indicate the adoption of small-scale saltmarsh planting to reduce erosion and enhance coastal functionality needs to ensure that wave energy is sufficiently dampened for adequate saltmarsh growth and, concomitantly, the conceived saltmarsh protection mechanism does not negatively impact adjacent SAV.
人类沿海居住活动常常导致自然海岸线结构特性和环境功能的退化。。。。已经有很多研究关注于各种生态岸线设计的成本效益，但对于通常应用于滨水住宅或娱乐地产的简单、小规模设计，还需要更多的工作。为了弥补这一空白，我们在墨西哥湾北部的两个地点种植了小规模的黑针蔺（Juncus roemerianus）斑块，一个位于住宅地产，另一个位于娱乐地产，这些地点都经历了显著的波浪能。斑块以两种不同的密度（初始覆盖率 50%或 100%）种植或不种植（对照），并在种植盐沼的同时，监测其演变情况，我们测量了一些功能指标，包括土壤坡度、斑块内和前面的浮游动物丰度，以及斑块前面的淹没水生植被（SAV）覆盖率，这些数据每月采集一次，共采集两年。在其中一个地点，植物覆盖率急剧下降，而在另一个地点，尽管用椰棕纤维捆保护了种植的盐沼，但我们没有观察到随着时间的推移植物覆盖率有任何显著变化（即在整个实验过程中，初始的 50%和 100%种植率保持在同一水平）。我们没有发现种植区和对照区之间土壤坡度或浮游动物丰度有任何变化。与对照区相比，种植区前面的 SAV 生长受到限制，这可能是由于椰棕纤维捆产生了有害影响。总的来说，结果表明，本实验中获得的对波浪能的保护不足以保证盐沼的充分建立和生长，从而导致植物密度降低或保持不变，以及种植区和非种植区之间的土壤坡度或浮游动物丰度没有显著差异。我们的结果表明，采用小规模盐沼种植来减少侵蚀和增强沿海功能需要确保波浪能充分减弱以促进盐沼生长，同时，所设想的盐沼保护机制不会对相邻的 SAV 产生负面影响。
