Unsworth Richard K F, Williams Beth, Jones Benjamin L, Cullen-Unsworth Leanne C
Seagrass Ecosystem Research Group, College of Science, Swansea UniversitySwansea, United Kingdom.
Project SeagrassCardiff, United Kingdom.
Front Plant Sci. 2017 Jul 25;8:1309. doi: 10.3389/fpls.2017.01309. eCollection 2017.
Seagrass meadows commonly reside in shallow sheltered embayments typical of the locations that provide an attractive option for mooring boats. Given the potential for boat moorings to result in disturbance to the seabed due to repeated physical impact, these moorings may present a significant threat to seagrass meadows. The seagrass (known as eelgrass) is extensive across the northern hemisphere, forming critical fisheries habitat and creating efficient long-term stores of carbon in sediments. Although boat moorings have been documented to impact seagrasses, studies to date have been conducted on the slow growing species' rather than the fast growing and rapidly reproducing that may have a higher capacity to resist and recover from repeated disturbance. In the present study we examine swinging chain boat moorings in seagrass meadows across a range of sites in the United Kingdom to determine whether such moorings have a negative impact on the seagrass at the local and meadow scale. We provide conclusive evidence from multiple sites that is damaged by swinging chain moorings leading to a loss of at least 6 ha of United Kingdom seagrass. Each swinging chain mooring was found to result in the loss of 122 m of seagrass. Loss is restricted to the area surrounding the mooring and the impact does not appear to translate to a meadow scale. This loss of United Kingdom seagrass from boat moorings is small but significant at a local scale. This is because it fragments existing meadows and ultimately reduces their resilience to other stressors. Boat moorings are prevalent in seagrass globally and it is likely this impairs their ecosystem functioning. Given the extensive ecosystem service value of seagrasses in terms of factors such as carbon storage and fish habitat such loss is of cause for concern. This indicates the need for the widespread use of seagrass friendly mooring systems in and around seagrass.
海草草甸通常生长在受庇护的浅海湾，这些地方是停泊船只的理想场所。由于船只停泊时反复的物理撞击可能会对海床造成干扰，因此这些停泊点可能会对海草草甸构成重大威胁。海草（称为大叶藻）在北半球广泛分布，形成了重要的渔业栖息地，并在沉积物中高效地长期储存碳。尽管已有文献记载船只停泊会对海草产生影响，但迄今为止的研究都是针对生长缓慢的海草物种，而非生长迅速且繁殖力强、可能具有更高抵抗反复干扰及从中恢复能力的海草。在本研究中，我们对英国一系列地点的海草草甸中的摆动链式船只停泊点进行了调查，以确定此类停泊点是否会在局部和草甸尺度上对海草造成负面影响。我们从多个地点提供了确凿证据，表明摆动链式停泊点会破坏海草，导致英国至少6公顷的海草损失。每个摆动链式停泊点都会导致122米的海草损失。损失仅限于停泊点周围区域，且这种影响似乎并未扩大到草甸尺度。英国因船只停泊造成的海草损失虽小，但在局部尺度上却很显著。这是因为它会分割现有的草甸，最终降低其对其他压力源的恢复能力。船只停泊在全球海草区域普遍存在，这可能会损害它们的生态系统功能。鉴于海草在碳储存和鱼类栖息地等方面具有广泛的生态系统服务价值，这种损失令人担忧。这表明需要在海草及其周边广泛使用对海草友好的停泊系统。
