Relationship between geological domain and physicochemical parameters in lotic system

ABSTRACT In natural conditions, the characteristics of surface water and river sediments are determined by geological formation. These can be changed due to human activities and interfere with maintenance of aquatic biota. Thus, identifying patterns of surface water and sediments in different geological areas can help to detect possible changes in orientation and contribute to decision-making within the maintenance and conservation of aquatic environments. The objective of this research was to identify changes in physical and chemical characteristics of surface water and geochemistry of sediments inserted catchments in three geological areas in Paraná: metasedimentary carbonate domain (MSCD), terrigenous-carbonate sedimentary domain (TCSD) and basic magmatic domain (MBD). The electrical conductivity, alkalinity, hardness, concentration of Ca and Mg in water were higher in MSCD. The concentration of SiO2 is more representative of the MBD and CO2 in the TCSD. In PCA, with the results of physico-chemical parameters of water, the first axis explained 99.43% of the variance between the sampling stations. In geochemical analysis of sediment and only Fe2O3 CaO showed statistically significant difference (ANOVA = p<0.05). The results suggest that the studied catchments are in good condition and reflect the natural conditions for each geological domain, demonstrating the need for adequacy of law inherent in assessing the quality of surface water. This work can be used as a reference for future studies and monitoring programs of the assessed catchments.

摘要
在自然条件下，地表水与河流沉积物的特征由地质建造所决定。此类特征可因人类活动发生改变，进而干扰水生生物群落的正常存续。因此，识别不同地质区域内地表水与沉积物的特征模式，有助于探测潜在的异常变化，为水生环境的维护与保护决策提供支撑。
本研究旨在识别巴拉那州（Paraná）三个地质区域内汇水区的地表水理化特征与沉积物地球化学特征变化，涉及的三个地质域分别为：变沉积碳酸盐岩域（metasedimentary carbonate domain, MSCD）、陆源-碳酸盐沉积岩域（terrigenous-carbonate sedimentary domain, TCSD）以及基性岩浆岩域（basic magmatic domain, MBD）。
变沉积碳酸盐岩域的水体电导率、碱度、硬度以及钙（Ca）、镁（Mg）浓度均处于较高水平。二氧化硅（SiO₂）浓度在基性岩浆岩域更为突出，而二氧化碳（CO₂）浓度则以陆源-碳酸盐沉积岩域为最高。
基于水体理化参数的主成分分析（Principal Component Analysis, PCA）结果显示，第一主轴解释了采样站点间99.43%的方差变异。沉积物地球化学分析仅显示三氧化二铁（Fe₂O₃）与氧化钙（CaO）存在统计学显著性差异（方差分析Analysis of Variance, ANOVA，p<0.05）。
研究结果表明，本次研究的汇水区整体状态良好，且各区域特征均符合对应地质域的自然本底条件，凸显了在地表水质量评估中完善相关法规的必要性。本研究可为后续相关研究以及目标汇水区的监测方案提供参考依据。