Physical and biological impact of marine aggregate extraction along the French coast of the Eastern English Channel: short- and long-term post-dredging restoration
Physical and biological impact of marine aggregate extraction along the French coast of the Eastern English Channel: short- and long-term post-dredging restoration
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DOI：
10.1006/jmsc.2000.0926
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发表时间：
2000-10-01
影响因子：
3.3
通讯作者：
Desprez, M
中科院分区：
文献类型：
--
作者：
Desprez, M
迪耶普附近一个工业开采地点的沉积物和相关大型动物群已在 10 年期间受到监测。卵石滩最初的异质基质以砾石和粗砂为特征，逐渐以疏浚道中沉积的细砂为主。对大型底栖动物的最大影响是物种丰富度减少 80%，丰度和生物量减少 90%。群落的结构从一种含有Branchiostoma lanceolatum的粗砂转变为含有Ophelia borealis、Nephtys cirrosa和Spiophanes bobyx的细砂之一，裸瓦上机会性的、无柄的Pomatoceros triqueter在当地占主导地位。事实证明，溢出的沙子对周围沉积区域的大型底栖动物的影响与疏浚区域的影响同样大。对 1995 年至 1997 年停止疏浚后重新殖民化的早期阶段进行了研究。 16个月后，物种丰富度已完全恢复，而28个月后，密度和生物量仍分别低于参考站的40%和25%。然而，群落结构与新型沉积物对应的最初群落结构不同。疏浚场地内部和周围的影响分为三个级别。对 20 世纪 70 年代疏浚的前实验场地 (CNEXO) 的勘探提供了长期修复的例子。 (C) 2000 年国际海洋探索理事会。
Sediment and associated macrofauna of an industrial extraction site off Dieppe have been monitored during a 10-year period. The original heterogeneous substrate of the shingle bank, characterized by gravels and coarse sands, was progressively dominated by fine sands deposited in dredging tracks. The maximum impact on benthic macrofauna was a reduction by 80% for species richness and 90% for both abundance and biomass. The structure of the community changed from one of coarse sands with Branchiostoma lanceolatum to one of fine sands with Ophelia borealis, Nephtys cirrosa, and Spiophanes bombyx, with local dominance of the opportunistic, sessile Pomatoceros triqueter on bare shingles. Impact of overflowing sands on benthic macrofauna in the surrounding deposition area proved equally large as in the dredged area. Early stages of recolonization were studied from 1995 to 1997 after cessation of dredging. Species richness has been fully restored after 16 months, while densities and biomass were still 40% and 25%, respectively, lower than in reference stations after 28 months. Nevertheless, community structure differed from the initial one corresponding to the new type of sediment. Impact within and around the dredging site was classified according to three levels. Exploration of a former experimental site (CNEXO) dredged in the 1970s provided an example of long-term restoration. (C) 2000 International Council for the Exploration of the Sea.