Influence of forest management on water quality and Hg dynamics : a synoptic research

Forest management is hypothesized to increase the mercury (Hg) load towards aquatic systems. In this study a synoptic research was carried out assessing 55 sites across Sweden, whereby the sampling scheme was designed to compare reference (N = 18), stump harvested (N = 16) and site prepared (N = 21)...

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Autor principal: Kraus, Andrea
Formato: L3
Lenguaje:Inglés
Publicado: SLU/Dept. of Aquatic Sciences and Assessment 2011
Materias:
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author Kraus, Andrea
author_browse Kraus, Andrea
author_facet Kraus, Andrea
author_sort Kraus, Andrea
collection Epsilon Archive for Student Projects
description Forest management is hypothesized to increase the mercury (Hg) load towards aquatic systems. In this study a synoptic research was carried out assessing 55 sites across Sweden, whereby the sampling scheme was designed to compare reference (N = 18), stump harvested (N = 16) and site prepared (N = 21) areas. The influence of forest treatment irrespective the separation into stump harvest and site preparation on Hg export to surface water streams was evaluated with regard to water quality (TOC, suspended solids, TSS) and with special focus on Hg and MeHg levels. Furthermore, the parameters affecting THg and MeHg concentrations were determined. Total phosphor (Ptot), total nitrogen (Ntot) and total organic carbon (TOC) concentrations were significantly higher in the treated areas compared to the reference sites (p = 0.0465, p = 0.0251 and p = 0.0487, respectively). THg revealed nearly significant higher concentration in the treated areas than in the reference site (p = 0.077). MeHg concentrations were not significantly differing between treated and reference areas, although a high standard deviation in the treated areas indicate that site specific catchment characteristics play an important role in the overall MeHg and THg mobilization. The individual comparison of stump harvested and site prepared areas showed no statistical significant difference. This might indicate that in general the treatment methods did not differ regarding their effects of Hg mobilization as well as nutrient and ion leaching on surface water quality. THg and MeHg correlated positive with TOC (R² = 0.70, p < 0.0001 and R² = 0.48, p < 0.0001). Furthermore, the quite strong significant correlation of THg and MeHg with absorption (unfiltered, 420 nm) that was R² = 0.66, p < 0.0001 and R² = 0.60, p < 0.0001, respectively, could favor the implementation of absorption measurement as a first estimate of Hg concentration in water. This study could not confirm the indications in literature that forest harvesting is severalfold increasing THg and MeHg load to aquatic systems.
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spelling RepoSLU31622012-10-06T17:57:10Z Influence of forest management on water quality and Hg dynamics : a synoptic research Kraus, Andrea Total Mercury Methylmercury Forestry site preparation stump harvest Forest management is hypothesized to increase the mercury (Hg) load towards aquatic systems. In this study a synoptic research was carried out assessing 55 sites across Sweden, whereby the sampling scheme was designed to compare reference (N = 18), stump harvested (N = 16) and site prepared (N = 21) areas. The influence of forest treatment irrespective the separation into stump harvest and site preparation on Hg export to surface water streams was evaluated with regard to water quality (TOC, suspended solids, TSS) and with special focus on Hg and MeHg levels. Furthermore, the parameters affecting THg and MeHg concentrations were determined. Total phosphor (Ptot), total nitrogen (Ntot) and total organic carbon (TOC) concentrations were significantly higher in the treated areas compared to the reference sites (p = 0.0465, p = 0.0251 and p = 0.0487, respectively). THg revealed nearly significant higher concentration in the treated areas than in the reference site (p = 0.077). MeHg concentrations were not significantly differing between treated and reference areas, although a high standard deviation in the treated areas indicate that site specific catchment characteristics play an important role in the overall MeHg and THg mobilization. The individual comparison of stump harvested and site prepared areas showed no statistical significant difference. This might indicate that in general the treatment methods did not differ regarding their effects of Hg mobilization as well as nutrient and ion leaching on surface water quality. THg and MeHg correlated positive with TOC (R² = 0.70, p < 0.0001 and R² = 0.48, p < 0.0001). Furthermore, the quite strong significant correlation of THg and MeHg with absorption (unfiltered, 420 nm) that was R² = 0.66, p < 0.0001 and R² = 0.60, p < 0.0001, respectively, could favor the implementation of absorption measurement as a first estimate of Hg concentration in water. This study could not confirm the indications in literature that forest harvesting is severalfold increasing THg and MeHg load to aquatic systems. SLU/Dept. of Aquatic Sciences and Assessment 2011 L3 eng https://stud.epsilon.slu.se/3162/
spellingShingle Total Mercury
Methylmercury
Forestry
site preparation
stump harvest
Kraus, Andrea
Influence of forest management on water quality and Hg dynamics : a synoptic research
title Influence of forest management on water quality and Hg dynamics : a synoptic research
title_full Influence of forest management on water quality and Hg dynamics : a synoptic research
title_fullStr Influence of forest management on water quality and Hg dynamics : a synoptic research
title_full_unstemmed Influence of forest management on water quality and Hg dynamics : a synoptic research
title_short Influence of forest management on water quality and Hg dynamics : a synoptic research
title_sort influence of forest management on water quality and hg dynamics : a synoptic research
topic Total Mercury
Methylmercury
Forestry
site preparation
stump harvest