%0 Journal Article
%T Macroinvertebrate communities associated with littoral zone habitats and the influence of environmental factors in Malilangwe Reservoir, Zimbabwe Les communaut¨¦s de macro-invert¨¦br¨¦s associ¨¦es aux habitats de la zone littorale et l¡¯influence des facteurs environnementaux dans le r¨¦servoir Malilangwe, Zimbabwe
%A Dalu T.
%A Clegg B.
%A Nhiwatiwa T.
%J Knowledge and Management of Aquatic Ecosystems
%D 2012
%I EDP Sciences
%R 10.1051/kmae/2012023
%X The aim of our study was to investigate macroinvertebrate communities so as to understand factors and processes structuring macroinvertebrate communities in a small reservoir, Malilangwe reservoir over seven months (April to October). Sampling was performed by active sweep netting and searching soil sediments. Water temperature, conductivity, dissolved oxygen, pH, ammonia, nitrogen, phosphorus, chemical oxygen demand and macrophyte cover were determined. In total, forty-two macroinvertebrate families belonging to 10 orders were identified amongst 13 macrophyte species and sediments. Thiaridae and Physidae (Mollusca) were the dominant and most abundant taxa (57.71%) and there were followed by the Hemiptera (27.31%). High indices for sites 1 to 3 for the Simpsons index, the Shannon-Weaver index and evenness were recorded, while low indices were observed for sites 4 to 5, with significant differences being observed among the study site using the Kruskal-Wallis ANOVA test (p < 0.05). Redundancy Analysis revealed that among environmental factors, hydrologically linked parameters such as conductivity, water level and macrophyte cover had the strongest influence on macroinvertebrate distribution. Le but de notre ¨¦tude ¨¦tait d¡¯¨¦tudier les communaut¨¦s de macro-invert¨¦br¨¦s de mani¨¨re ¨¤ comprendre les facteurs et les processus qui structurent ces communaut¨¦s dans un petit r¨¦servoir, r¨¦servoir Malilangwe, au cours de sept mois (avril ¨¤ octobre). L¡¯¨¦chantillonnage a ¨¦t¨¦ effectu¨¦ par balayage actif et prospection des s¨¦diments. La temp¨¦rature de l¡¯eau, la conductivit¨¦, l¡¯oxyg¨¨ne dissous, le pH, l¡¯ammoniac, l¡¯azote, le phosphore, la demande chimique en oxyg¨¨ne et la couverture de macrophytes ont ¨¦t¨¦ d¨¦termin¨¦s. Au total, quarante-deux familles de macro-invert¨¦br¨¦s appartenant ¨¤ 10 ordres ont ¨¦t¨¦ identifi¨¦es dans les 13 esp¨¨ces de macrophytes et les s¨¦diments. Thiaridae et Physidae (Mollusca) ¨¦taient les taxons dominants et les plus abondants (57,71 %), suivis par les Hemiptera (27,31 %). Des valeurs ¨¦lev¨¦es pour les sites de 1 ¨¤ 3 de l¡¯indice de Simpson, de l¡¯indice de Shannon-Weaver et de la r¨¦gularit¨¦ ont ¨¦t¨¦ observ¨¦es, tandis que des indices faibles ont ¨¦t¨¦ observ¨¦s pour les sites 4 ¨¤ 5, avec des diff¨¦rences significatives observ¨¦es entre les sites d¡¯¨¦tude en utilisant le test ANOVA de Kruskal-Wallis (p < 0,05). L¡¯analyse de redondance a r¨¦v¨¦l¨¦ que parmi les facteurs environnementaux, les param¨¨tres li¨¦s ¨¤ l¡¯hydrologie tels que la conductivit¨¦, le niveau de l¡¯eau et la couverture de macrophytes ont la plus forte influence sur la distribution des macro-invert¨¦br¨¦s.
%K Macroinvertebrates
%K diversity
%K Malilangwe reservoir
%K macrophyte cover
%K conductivity
%K water level
%K macro-invert¨¦br¨¦s
%K biodiversit¨¦
%K r¨¦servoir Malilangwe
%K macrophytes
%K conductivit¨¦
%U http://dx.doi.org/10.1051/kmae/2012023