Metal concentrations in lake sediments

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Question

What are metal concentrations in lake sediments? The focus is on Finland.

Answer

1) Calculate the metal concentration based on the mean value of the surrounding lakes (spherical area specified by radius)

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Valitse näytettävä metalli: Co Cr Cu Fe Mn Ni Pb S V Zn + Show code- Hide code library(OpasnetBaseUtils) library(xtable) library(ggplot2) data <- tidy(op_baseGetData("opasnet_base", "Op_en5462")) out <- data[data$Observation %in% metalli, ] colnames(out) <- c("DateTime", "TagName", "Value") out$Value <- as.numeric(out$Value) out$DateTime <- as.numeric(out$DateTime) cat(paste("Metalli: ", metalli, "\n", sep="")) plot(out$Value)

Northing: Easting: Valitse ympyrän säde(km; järvet ko. alueelta huomioidaan): Valitse metallit: Co Cr Cu Fe Mn Ni Pb S V Zn + Show code- Hide code library(OpasnetBaseUtils) library(xtable) library(ggplot2) library(reshape) data <- (op_baseGetData("opasnet_base", "Op_en5462")) data <- tidy(data) data$Result <- as.numeric(data$Result) # This replaces all as.numeric rows below. data <- reshape(data, timevar = "Observation", idvar = "ID", direction = "wide") colnames(data) <- gsub("Result.", "", colnames(data)) data$distance <- sqrt((as.numeric(data$Easting) - easting)^2 + (as.numeric(data$Northing) - northing)^2) data <- melt(data, measure.vars = c("Co", "Cr", "Cu", "Fe", "Mn", "Ni", "Pb", "S", "V", "Zn")) out <- data out$distance <- data$distance <= säde*1000 out <- as.data.frame(as.table(tapply(out$value, out[c("variable", "distance")], mean))) colnames(out) <- gsub("variable", "metalli", colnames(out)) colnames(out) <- gsub("Freq", "pitoisuus", colnames(out)) cat("Metallipitoisuuden keskiarvo ", säde, " km säteellä pisteestä ", easting, "E, ", northing, " N.\n") print(xtable(out[out$distance == TRUE, ]), type = 'html') cat("Pitoisuudet metallille", metalli, ".\n") concentration <- data[data$distance <= säde*1000 & data$variable == metalli, "value"] plot(concentration) # simple plot about concentrations. qplot(Easting, Northing, data = data[data$variable == metalli, ], size = value) # Concentrations on a "map".

2) Calculate the concentration based on the concentration of a big lake

Name of the big lake: Concentration in big lake: Coefficient for pH: Coefficient for land use: Select the metals: Co Cr Cu Fe Mn Ni Pb S V Zn + Show code- Hide code concentration <- "concentration in big lake" * "coefficient for pH" * "coefficient for land use"

Rationale

Based on data from GTK, Finland.

Related files

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Metal concentrations in lake sediments. Opasnet . [1]. Accessed 09 Apr 2025.