en Ecology Ecology پژوهشي Orginal research papers <font face="Times New Roman" size="3"> </font><p class="MsoNormal" style="margin: 0cm 0cm 0pt text-align: justify line-height: 120%"><font size="3"><font face="Times New Roman"><span style="line-height: 120% mso-bidi-font-size: 12.0pt">Benthic invertebrates are a well-established target in environmental quality status evaluations. The AMBI (AZTI's Marine Biotic Index) was developed to determine the impacts and the quality status of soft-bottom marine benthic communities. <span style="color: black">The aim of this study was investigating multivariate pattern of benthic invertebrate community and application of AMBI (AZTI's Marine Biotic Index) for determining quality of health status in Khuzestan coastal waters.</span> </span><span style="line-height: 120% mso-fareast-font-family: "Arial Unicode MS" mso-bidi-font-size: 12.0pt">Seasonal samplings were collected from eight creeks over one year study by Peterson grab sampler, beginning from October 2005. </span><span style="color: black line-height: 120% mso-bidi-language: FA mso-bidi-font-size: 12.0pt mso-fareast-language: FA">All creeks are characterized by muddy bottom.</span><span style="line-height: 120% mso-bidi-language: FA mso-bidi-font-size: 12.0pt mso-fareast-language: FA"> According to sensitivity to environmental stress, </span><span style="line-height: 120% mso-fareast-font-family: "Arial Unicode MS" mso-bidi-font-size: 12.0pt">macrobenthic animals</span><span style="line-height: 120% mso-bidi-language: FA mso-bidi-font-size: 12.0pt mso-fareast-language: FA"> classified into 5 ecological groups.<span style="color: black"> </span>Among 28<span style="color: black"> identified faunal groups the most abundant groups were polychaets, molluscs, c</span>rustaceans<span style="color: black"> and nematodes, respectively. </span>Two way ANOVAs showed only seasonal significant differences in mean abundance (P<0.05) and Margalef richness index values (P<0.05), while all of studied creeks shows similar biological characters based on benthic communities.<span style="color: black"> </span>According to annual mean of AMBI value all creeks were in ecological group III with slightly polluted condition, except for Darvish that was in unpolluted category.<span style="color: black"> </span>In the present study, although the number of species initially increased, but due to appearance of dominant species such as <i>Capitella</i> sp.<i> </i>and nematods (as opportunist species)<i>, </i>diversity values reduced. In general, according to AMBI and Biotic index values, the most creeks are classified into unpolluted and slightly polluted categories except for Zangy, Doragh and Patil in summer and also Zangy and Bihad in winter which was in moderate to heavily polluted category. D</span><span style="line-height: 120% mso-bidi-font-size: 12.0pt">ifferent types of exploitation, industrial<span style="color: red"> </span>and shipping activities in this area could result in unbalanced to polluted status in benthic animals (as the best indicators in sediment quality assessment) so</span><span style="line-height: 120% mso-bidi-language: FA mso-bidi-font-size: 12.0pt mso-fareast-language: FA"> these results can be acceptable.<o:p /></span></font></font></p><font face="Times New Roman" size="3"> </font> AMBI, Contaminant assessment, Khur-e-Mussa creeks, Persian Gulf 460 474 http://jifro.ir/browse.php?a_code=A-10-1-171&slc_lang=en&sid=1 S. Dehghan Madiseh s_dehghan2002@yahoo.com 10031947532846004143 10031947532846004143 Yes F. Esmaily 10031947532846004144 10031947532846004144 No J. G. Marammazi 10031947532846004145 10031947532846004145 No E. Koochaknejad 10031947532846004146 10031947532846004146 No S. Farokhimoghadam 10031947532846004147 10031947532846004147 No