This study investigated the biodiversity and hydrochemistry of seven unconfined aquifers located in two hydrogeological complexes in the north-western region of Algeria. The aim of the study was to: (1) contribute new data on the biodiversity and distribution patterns of groundwater fauna in groundwater bodies in North Africa, (2) assess whether the current biodiversity patterns of groundwater taxa reflect the difference in aquifer type, hydrogeological conditions and hydrochemistry, and (3) evaluate the role of hydrogeological, geographical and physicochemical variables in determining the distribution pattern of groundwater invertebrates. Sixty-three wells were investigated between August 2010 and June 2013. In total, 41,297 specimens belonging to 51 taxa, 10 of which were crustaceans, were collected during the survey. Taxa abundances varied significantly between aquifer types, but not between the two hydrogeological complexes (continental and littoral). The groundwater assemblages collected in seven aquifers in northwest Algeria differed significantly between aquifer types in this region. The distribution of groundwater fauna across the whole study area was primarily affected by distance to streams, the geological period and electrical conductivity. Overall, the assemblages showed a spatial distribution that to some extent mirrored the hydrogeological and hydrochemical conditions of groundwater in the north-western part of Algeria. These findings suggest that groundwater biota, and crustaceans in particular, may play a key role in distinguishing between the typologies of the investigated aquifers. This study contributes to knowledge of current groundwater biodiversity in northwest Algeria and demonstrates that this knowledge is still far from being complete.

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决定阿尔及利亚西北半干旱含水层地下水动物区系生物多样性格局的环境因素

这项研究调查了位于阿尔及利亚西北部两个水文地质综合体中的七个非承压含水层的生物多样性和水化学特征。该研究的目的是：（1）提供有关北非地下水体中地下水动物群落的生物多样性和分布模式的新数据，（2）评估当前地下水分类单元的生物多样性模式是否反映了含水层类型，水文地质学的差异条件和水化学，以及（3）评价水文地质，地理和理化变量在确定地下水无脊椎动物分布格局中的作用。在2010年8月至2013年6月期间，共调查了63口井。在调查期间，共收集了51类群的41297个标本，其中10个为甲壳类。含水层类型之间的分类单元丰度差异很大，但两种水文地质综合体（大陆和沿海）之间的分类单元丰度差异很大。阿尔及利亚西北部七个含水层中收集的地下水组合在该地区的不同含水层类型之间存在显着差异。整个研究区域中地下水动物区系的分布主要受与溪流的距离，地质时期和电导率的影响。总体而言，这些组合物显示出一定的空间分布，在一定程度上反映了阿尔及利亚西北部地区地下水的水文地质和水化学状况。这些发现表明，地下水生物区系，尤其是甲壳类，可能在区分所调查含水层的类型方面起关键作用。