Ecological effects of coastal armoring on sandy beaches
Ecological effects of coastal armoring on sandy beaches
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DOI：
10.1111/j.1439-0485.2008.00231.x
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发表时间：
2008-07-01
影响因子：
1.1
通讯作者：
Schroeter, Stephen
中科院分区：
文献类型：
--
作者：
Dugan, Jenifer E.;Hubbard, David M.;Schroeter, Stephen
由于人口不断增加、海滩侵蚀和沿海海平面上升，预计沿海装甲的使用将会增加。为了提供概念框架，我们提出了关于与海岸装甲相关的海滩栖息地丧失的生态影响的假设。由于海滩因装甲而变窄，干燥的上层潮间带会不成比例地消失，从而减少可用的栖息地类型以及大型无脊椎动物的多样性和丰度。诸如滨鸟之类的捕食者可能会对以下因素做出反应：（i）栖息地丧失； ㈡ 涨潮时通行能力下降； (iii) 装甲海滩上的猎物数量减少。为了验证这些预测，我们对南加州狭窄陡峭海滩的成对装甲和非装甲部分的区域宽度以及大型无脊椎动物和鸟类的分布和丰度进行了比较。我们的结果支持了预测，并揭示了装甲对鸟类的一些意想不到的影响。与邻近的非装甲部分相比，装甲部分缺乏干燥的上海滩区域，并且中海滩区域全年较窄（> 2倍）。装甲节上潮间带上游大型无脊椎动物的丰度、生物量和大小也明显较低。大多数滨鸟正在觅食，其反应如预期的那样，装甲节上的物种丰富度（两倍）和丰度（> 3倍）显着降低。海鸥和其他鸟类（包括海鸟）主要利用海滩栖息，它们在装甲部分的数量也明显较低（分别> 4倍和> 7倍），这是一个重要的意外结果。鉴于沿海开发、侵蚀和海平面上升对沙滩造成的压力不断加大，我们的研究结果表明，需要进一步调查沿海装甲的生态反应，以管理和保护这些生态系统。
Use of coastal armoring is expected to escalate in response to the combination of expanding human populations, beach erosion, and sea level rise along the coasts. To provide a conceptual framework, we developed hypotheses concerning the ecological effects of beach habitat loss associated with coastal armoring. As beaches narrow in response to armoring, dry upper intertidal zones should be lost disproportionately, reducing the habitat types available and the diversity and abundance of macroinvertebrates. Predators, such as shorebirds, could respond to a combination of (i) habitat loss; (ii) decreased accessibility at high tides; and (iii) reduced prey availability on armored beaches. To examine those predictions, zone widths and the distribution and abundance of macroinvertebrates and birds were compared on paired armored and unarmored segments of narrow bluff-backed beaches in southern California. Our results supported the predictions and revealed some unexpected effects of armoring on birds. Dry upper beach zones were lacking and mid-beach zones were narrower (> 2 times) year-round on armored segments compared to adjacent unarmored segments. The abundance, biomass and size of upper intertidal macroinvertebrates were also significantly lower on armored segments. Shorebirds, most of which were foraging, responded predictably with significantly lower species richness (two times) and abundance (> 3 times) on armored segments. Gulls and other birds (including seabirds), which use beaches primarily for roosting, were also significantly lower in abundance (> 4 times and > 7 times respectively) on armored segments, an important unexpected result. Given the accelerating pressures on sandy beaches from coastal development, erosion and rising sea levels, our results indicate that further investigation of ecological responses to coastal armoring is needed for the management and conservation of these ecosystems.