Effect of deforestation on stream water chemistry in the Skrzyczne massif (the Beskid Śląski Mountains in southern Poland)

Amanda Kosmowska; Mirosław Żelazny; Stanisław Małek; Joanna Paulina Siwek; Łukasz Jelonkiewicz

doi:10.1016/j.scitotenv.2016.06.123

Effect of deforestation on stream water chemistry in the Skrzyczne massif (the Beskid Śląski Mountains in southern Poland)

Sci Total Environ. 2016 Oct 15:568:1044-1053. doi: 10.1016/j.scitotenv.2016.06.123. Epub 2016 Jun 28.

Authors

Amanda Kosmowska¹, Mirosław Żelazny¹, Stanisław Małek², Joanna Paulina Siwek¹, Łukasz Jelonkiewicz¹

Affiliations

¹ Department of Hydrology, Institute of Geography and Spatial Management, Jagiellonian University in Kraków, Gronostajowa 7, 30-387 Kraków, Poland.
² Department of Forest Ecology and Reclamation, Institute of Forest Ecology and Silviculture, Faculty of Forestry, University of Agriculture in Krakow, Al. 29-go Listopada 46, 31-425 Kraków, Poland.

PMID: 27363347
DOI: 10.1016/j.scitotenv.2016.06.123

Abstract

The purpose of the study was to identify the factors affecting stream water chemistry in the small mountain catchments deforested to varying degrees, from 98.7 to 14.1%, due to long-term acid deposition. Water samples were collected monthly in 2013 and 2014 from 17 streams flowing across three distinct elevation zones in the Skrzyczne massif (Poland): Upper, Middle and Lower Forest Zone. Chemical and physical analyses, including the pH, electrical conductivity (EC), total mineral content (Mt), water temperature, and the concentrations of Ca(2+), Mg(2+), Na(+), K(+), HCO3(-), SO4(2-), Cl(-), and NO3(-), were conducted. Based on Principal Component Analysis (PCA), the most important factor affecting water chemistry was human impact associated with changes in pH, SO4(2-) concentration, and the concentration of most of the main ions. The substantial acidity of the studied environment contributed to the exclusion of natural factors, associated with changes in discharge, from the list of major factors revealed by PCA. All of the streams were characterized by very low EC, Mt, and low concentrations of the main ions such as Ca(2+) and HCO3(-). This is the effect of continuous leaching of solutes from the soils by acidic precipitation. The lowest parameter values were measured for the streams situated in the Upper Forest Zone, which is associated with greater acid deposition at the higher elevations. In the streams located in the Upper Forest Zone, a higher percentage of SO4(2-) occurred than in the streams situated in the Middle and Lower Forest Zones. However, the largest share of SO4(2-) was measured in the most deforested catchment. The saturation of the studied deforested catchment with sulfur compounds is reflected by a positive correlation between SO4(2-) and discharge. Hence, a forest acts as a natural buffer that limits the level of acidity in the natural environment caused by acidic atmospheric deposition.

Keywords: Acidic atmospheric deposition; Deforestation; Leaching of ions from the soils; Nitrogen; Stream water chemistry; Sulfur.