Silva Gicelle M F, Andrade Marcelo C, Silva Breno R M, Palheta Ingrid S, Gonçalves Liziane B, Rocha Rossineide M, Ferreira Maria A P
Laboratório de Imunohistoquímica e Biologia do Desenvolvimento Universidade Federal do Pará Belém Brazil.
Laboratório de Ultra Estrutura Celular Universidade Federal do Pará Belém Brazil.
Ecol Evol. 2020 Jun 20;10(13):6536-6548. doi: 10.1002/ece3.6388. eCollection 2020 Jul.
In recent years, species richness and diversity in aquatic ecosystems has declined as environments are increasingly impacted by anthropic actions. Freshwater prawns are well adapted to survive in a disturbed and heterogeneous environment. For instance, Amazon river prawn () populations vary in migratory behavior between rivers and estuaries, depending on factors such as dams. However, there is limited information on the influence of environmental conditions on life-history traits of this species, which we investigate here using two distinct and unconnected aquatic systems, a dammed river and an estuary, in the eastern Brazilian Amazon. The biological characteristics of 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 estuary and river. prawns in the estuary were larger and heavier than those in the river during rainy periods. The mass-length ratios and condition factor varied significantly between the populations in the estuary and river, with negative allometric growth (grows faster in length than in weight) predominating in both populations, and condition factor was better in the estuary for males and in the river for females. The relative frequencies of occurrence of the different female maturation stages and the male morphotypes were related to precipitation and turbidity in both environments and also to salinity in the estuary. In these two distinct aquatic systems, the abiotic parameters determined by the seasonal precipitation cycle profoundly influenced the development of this crustacean, despite its ecological plasticity. Overall, the study showed that river damming triggered environmental changes in the freshwater river ecosystem and played a key role in determining the life-history characteristics of in these contrasting aquatic systems.
近年来，随着环境日益受到人类活动的影响，水生生态系统中的物种丰富度和多样性有所下降。淡水虾非常适应在受干扰的异质环境中生存。例如，亚马逊河虾（）的种群在河流和河口之间的洄游行为存在差异，这取决于水坝等因素。然而，关于环境条件对该物种生活史特征的影响的信息有限，我们在此利用巴西亚马逊东部两个不同且不相连的水生系统——一条筑坝河流和一个河口——对此进行研究。比较了两个环境中虾种群的生物学特征，并将其与环境参数相关联，这两个环境之间以及不同季节之间存在显著差异。河口和河流中的溶解氧、降水量和温度随季节变化最为显著。雨季时，河口的虾比河流中的虾更大更重。河口和河流中虾种群的质量 - 长度比和状况因子存在显著差异，两个种群均以负异速生长（体长生长速度快于体重）为主，且河口雄性虾的状况因子更好，河流雌性虾的状况因子更好。在两个环境中，不同雌性成熟阶段和雄性形态型的相对出现频率均与降水量和浊度有关，在河口还与盐度有关。在这两个不同的水生系统中，尽管该甲壳类动物具有生态可塑性，但由季节性降水周期决定的非生物参数对其发育产生了深远影响。总体而言，研究表明河流筑坝引发了淡水河流生态系统的环境变化，并在决定这些对比鲜明的水生系统中虾的生活史特征方面发挥了关键作用。
