Next Article in Journal
Evaluating Evaporation Methods for Estimating Small Reservoir Water Surface Evaporation in the Brazilian Savannah
Previous Article in Journal
Machine Learning Approaches to Develop Pedotransfer Functions for Tropical Sri Lankan Soils
Previous Article in Special Issue
An Assessment of Groundwater Contamination Risk with Radon Based on Clustering and Structural Models
Open AccessArticle

Seasonal and Scale Effects of Anthropogenic Pressures on Water Quality and Ecological Integrity: A Study in the Sabor River Basin (NE Portugal) Using Partial Least Squares-Path Modeling

1
Centro de Investigação e Tecnologias Agroambientais e Biológicas, Universidade de Trás-os-Montes e Alto Douro, Ap 1013, 5001-801 Vila Real, Portugal
2
Centro de Química de Vila Real, Universidade de Trás-os-Montes e Alto Douro, Ap 1013, 5001-801 Vila Real, Portugal
*
Author to whom correspondence should be addressed.
Water 2019, 11(9), 1941; https://doi.org/10.3390/w11091941
Received: 4 June 2019 / Revised: 5 September 2019 / Accepted: 6 September 2019 / Published: 18 September 2019
Interactions between pollution sources, water contamination, and ecological integrity are complex phenomena and hard to access. To comprehend this subject of study, it is crucial to use advanced statistical tools, which can unveil cause-effect relationships between pressure from surface waters, released contaminants, and damage to the ecological status. In this study, two partial least squares-path models (PLS-PM) were created and analyzed in order to understand how the cause-effect relationships can change over two seasons (summer and winter) and how the used scale (short or long) can affect the results. During the summer of 2016 and winter of 2017 surface water parameters and the North Invertebrate Portuguese Index were measured in strategic sampling sites. For each site, it two sections were delineated: the total upstream drainage area (long scale) and 250 m (short scale). For each section, data of pressures in surface waters including point source, diffuse emissions and landscape metrics were gathered. The methodology was applied to the Sabor River Basin, located in the northeast of Portugal. In this study, it was possible to determine in which season pressures affect ecological integrity and also which scale should be addressed. The models showed the influences of manganese and of potassium concentrations in stream water on the decrease in summer water quality, while arsenic’s harmful effect occurs during winter. Pastures and environmental land use conflicts were considered threats to water quality when analyzed on a long scale, whereas agricultural areas played a role when the short scale was used. The effect of landscape edge density revealed to be independent of scale or season. Effluent discharges in surface water affected the water quality during the summer season, while the effect of discharges in groundwater affected the water quality in winter. It has also been found that, to find the harmful effect of pressures, it is necessary to approach different scales and that the role of landscape metrics can also overlap contaminant sources. View Full-Text
Keywords: water quality; pollution sources; landscape metrics; scale effects; seasonality; PLS-PM water quality; pollution sources; landscape metrics; scale effects; seasonality; PLS-PM
Show Figures

Figure 1

MDPI and ACS Style

Fernandes, A.C.P.; Sanches Fernandes, L.F.; Terêncio, D.P.S.; Cortes, R.M.V.; Pacheco, F.A.L. Seasonal and Scale Effects of Anthropogenic Pressures on Water Quality and Ecological Integrity: A Study in the Sabor River Basin (NE Portugal) Using Partial Least Squares-Path Modeling. Water 2019, 11, 1941. https://doi.org/10.3390/w11091941

AMA Style

Fernandes ACP, Sanches Fernandes LF, Terêncio DPS, Cortes RMV, Pacheco FAL. Seasonal and Scale Effects of Anthropogenic Pressures on Water Quality and Ecological Integrity: A Study in the Sabor River Basin (NE Portugal) Using Partial Least Squares-Path Modeling. Water. 2019; 11(9):1941. https://doi.org/10.3390/w11091941

Chicago/Turabian Style

Fernandes, António C.P.; Sanches Fernandes, Luís F.; Terêncio, Daniela P.S.; Cortes, Rui M.V.; Pacheco, Fernando A.L. 2019. "Seasonal and Scale Effects of Anthropogenic Pressures on Water Quality and Ecological Integrity: A Study in the Sabor River Basin (NE Portugal) Using Partial Least Squares-Path Modeling" Water 11, no. 9: 1941. https://doi.org/10.3390/w11091941

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop