Has a river dam affected the life-history traits of a freshwater prawn?

In recent years, species richness and diversity in aquatic ecosystems has declined as environments are increasingly impacted by anthropic actions. Freshwater prawns are among the aquatic organisms most capable to survive in a heterogeneous environment. Due to factors such as the distance from an estuary or dam, Macrobrachium amazonicum populations in rivers do not show amphidromy. So, the present study investigated the influence of environmental conditions on life-history traits of the Amazon river prawn, M. amazonicum, in two distinct and unconnected aquatic systems, with different salinity, a dammed river and an estuary, in the eastern Brazilian Amazon. The biological characteristics of M. amazonicum populations in the two environments were compared and related to environmental parameters, which differed significant differences between the two environments and between seasons. Dissolved oxygen, precipitation, and temperature varied most significantly with the seasons in both the estua...

近年来，随着人类活动对水生生态系统的影响日益加剧，其物种丰富度（species richness）与生物多样性（diversity）均呈下降趋势。淡水虾是最能在异质环境（heterogeneous environment）中存活的水生生物类群之一。由于距河口或大坝的距离等因素，河流中的亚马逊长臂虾（Macrobrachium amazonicum）种群不具备双向洄游（amphidromy）习性。为此，本研究以巴西亚马逊东部区域的两个独立且互不连通的水生系统为研究对象——分别为一座受大坝调控的河流与一处河口，二者盐度（salinity）存在显著差异——探究了环境条件对亚马逊长臂虾（Macrobrachium amazonicum，下称M. amazonicum）生活史特征的影响。本研究对比了两个生境中该种群的生物学特征，并将其与环境参数进行关联分析；结果显示，两个生境间以及不同季节间的环境参数均存在显著差异。溶解氧（dissolved oxygen）、降水量（precipitation）与温度（temperature）在两个生境中均随季节发生最为显著的变化，相关数据来自河口……