Medeiros C R, Paiva F F, Ferreira L M R, Costa L D A, Nóbrega R L B, Cunha J, Molozzi J, Galvão C O
Programa de Pós-Graduação em Engenharia Civil e Ambiental, Universidade Federal de Campina Grande, 58429-900 Campina Grande, PB, Brazil.
Programa de Pós-Graduação em Ecologia e Conservação, Universidade Estadual da Paraíba, 58429-500 Campina Grande, PB, Brazil.
Sci Total Environ. 2025 Jan 1;958:177881. doi: 10.1016/j.scitotenv.2024.177881. Epub 2024 Dec 12.
In the current environmental crisis scenario, it becomes increasingly important to understand the hydroclimatic effects on the availability and quality of water resources and their impacts on aquatic biodiversity. The understanding of how these components are interconnected is necessary to support initiatives for monitoring and managing water resources and protecting biodiversity. In this study, we analyzed the hierarchical effects and dissociated the complex relationships between the storage volume of tropical semi-arid reservoirs on water quality and the diversity of benthic macroinvertebrates. We analyzed these nested hierarchical relationships using Structural Equation Modeling (SEM). Our results showed that the storage volume of the reservoirs exhibited a negative effect on total phosphorus (TP) but a positive effect on chlorophyll-a, and these parameters exhibited mediated effects on the richness and abundance of benthic macroinvertebrates. While TP had a positive mediated effect on abundance, chlorophyll-a exhibited a negative mediated effect on the abundance and richness of benthic macrofauna. Furthermore, DIN exhibited only a direct negative effect on richness and the Simpson's index. These results indicate that in periods of increased storage volume, there is a reduction in TP concentrations in water due to their dilution. However, despite this dilution, nutrient concentrations in ecosystems still favor primary productivity. We found that semi-arid reservoirs are ecosystems susceptible to environmental degradation, even in periods of increased storage volume due to the hydrological dynamics of the region. This causes the enrichment of nutrients in the reservoirs, with noticeable impacts on the diversity of benthic macroinvertebrates. These results highlight the need for adequate monitoring and management measures of strategic water resources in semi-arid regions to promote the health and integrity of reservoirs and the promotion of their ecosystem services.
在当前的环境危机背景下，了解水文气候对水资源可用性和质量的影响及其对水生生物多样性的影响变得越来越重要。了解这些组成部分之间的相互联系对于支持水资源监测和管理以及保护生物多样性的举措至关重要。在本研究中，我们分析了层次效应，并解析了热带半干旱水库蓄水量与水质和底栖大型无脊椎动物多样性之间的复杂关系。我们使用结构方程模型（SEM）分析了这些嵌套的层次关系。我们的结果表明，水库蓄水量对总磷（TP）有负面影响，但对叶绿素-a有正面影响，并且这些参数对底栖大型无脊椎动物的丰富度和丰度有中介效应。虽然TP对丰度有正向中介效应，但叶绿素-a对底栖动物的丰度和丰富度有负向中介效应。此外，溶解性无机氮（DIN）仅对丰富度和辛普森指数有直接负面影响。这些结果表明，在蓄水量增加的时期，由于稀释作用，水中的TP浓度会降低。然而，尽管有这种稀释作用，生态系统中的营养物质浓度仍然有利于初级生产力。我们发现，即使在因该地区水文动态导致蓄水量增加的时期，半干旱水库也是易受环境退化影响的生态系统。这导致水库中营养物质的富集，对底栖大型无脊椎动物的多样性产生显著影响。这些结果凸显了对半干旱地区战略水资源采取适当监测和管理措施的必要性，以促进水库的健康和完整性，并提升其生态系统服务功能。
