Distribution and ecological relevance of fine sediments in organic-enriched lagoons: The case study of the Cabras lagoon (Sardinia, Italy)

被引：72

作者：

Magni, P. ^{[1
,2
]}

De Falco, G. ^{[1
,2
]}

Como, S. ^{[2
]}

Casu, D. ^{[3
]}

Floris, A. ^{[4
]}

Petrov, A. N. ^{[5
]}

Castelli, A. ^{[6
]}

Perilli, A. ^{[1
,2
]}

机构：

[1] IAMC, CNR, Natl Res Council, Inst Coastal Marine Environm Localita Sa Mardini, I-09072 Torregrande, Oristano, Italy

[2] Int Marine Ctr, I-09072 Torregrande, Oristano, Italy

[3] Univ Sassari, Dip Bot Ecol Vegetale, I-07100 Sassari, Italy

[4] Univ Sassari, Dip Zool & Genet Evoluzionistica, I-07100 Sassari, Italy

[5] NASU, Inst Biol So Seas, UA-99011 Sevastopol, Ukraine

[6] Univ Pisa, Dipartimento Biol, I-56126 Pisa, Italy

来源：

MARINE POLLUTION BULLETIN | 2008年 / 56卷 / 03期

关键词：

fine sediments; mud; organic matter (OM); macrofauna; ecological quality; coastal lagoons;

D O I：

10.1016/j.marpolbul.2007.12.004

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

In organic-enriched sedimentary systems, like many Mediterranean coastal lagoons, a detailed analysis of sediment grain size composition and partitioning within the muds is crucial to investigate sedimentological trends related to both hydrodynamic energy and basin morphology. In these systems, sediment dynamics are particularly important because the partitioning and transport of fine sediments can strongly influence the redistribution and accumulation of large amounts of organic matter, and consequently the distribution of benthic assemblages and the trophic status and functioning of a lagoon. Nevertheless, studies on benthic-sediment relationships have been based mainly on a rather coarse analysis of sediment grain size features. In muddy systems, however, this approach may impede a proper evaluation of the relationships and effects of the distribution of fine sediment and organic matter on the biotic benthic components. Here we show that the distribution of sedimentary organic matter (OM) and total organic carbon (TOC) in the Cabras lagoon (Sardinia, Italy) can be explained (i.e., predicted) as a function of a nonlinear increase in the amount of the cohesive fraction of sediments (<= 8 mu m grain size particles) and that this fraction strongly influences the structure, composition and distribution of macrobenthic assemblages. Even in such a homogeneously muddy system, characterized by "naturally" occurring impoverished communities, impaired benthic assemblages were found at <= 8 mu m, OM, TOC contents of about 77%, 11% and 3.5%, respectively. A review of studies conducted in Mediterranean coastal lagoons highlighted a lack of direct integrated analysis of sediment features and the biotic components. We suggest that, especially in organic-enriched coastal lagoons, monitoring programs should primarily investigate and consider the cohesive fraction of sediments in order to allow a better assessment of benthic-sediment relationships and ecological quality of the system. (C) 2007 Elsevier Ltd. All rights reserved.

引用

页码：549 / 564

页数：16