\textbf{Effects of the variables}
higher precipitation has always a positive effect on concentration (no effect on Pb).


\textbf{Effects at different horizons}

BD and ET are most effective in A horizon. CEC and clay are most effective in C horizon. Precipitation and SOC are equally important in A\&C horizon.

Most variables effects are stronger below ground, SOC and CEC are much less effective in the topsoil. Only precipitation and temp are more important in topsoil.

\textbf{Element behavior in zones}\\
Soil elements have the highest concentrations in soil driven zones, climate elements in climate driven zones.

Variables are more effective in zones which are defined after them (e.g. SOC is more important in zones with high SOC content)

The mechanisms driving the elements do not vary a lot among the zones but the concentrations of the elements differ a lot (except As, Hg, S and Se. Hg ans S have very little concentrations tough...)

\textbf{Unexpected things?}\\

Hg no plant uptake but ET is important...?

Se is volantilized by plants but ET is positive. Se binds strongly to SOC --> ET

S is very rapidly mobile and taken up --> difficult to predict? all variables important but CEC, temp








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Meeting with Lenny\\
S, Hg and Se not affected by leaching. maybe by et as temperature is optimal for plant growth when precip is lowest (in the middle)\\

start with hypothesis for easy things: clay, soc. show proof that model works. then precip and leaching. WOW. neglect BD and stuff that is boring.\\

Clay: groups of elements in top5.\\
What is clay composed of? mostly Fe and thus Fe is a bit meaningless\\

How do we expect elements to be typically present in the soil? how is it then affected? Ca is CaCo3. therefore \\

S is shitty but the results in the sens anal make sense. Interesting.

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Observations\\
Cu stronger clay dependent in deeper horizons



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Deleted shit from results\\


The effect of BD was expected to be negative for elements primary sorbed onto SOC as SOC is a relatively lightweight soil content. Elements sorbed primarly onto the more heavy clays however were expected to be positively influenced by BD.
In the sensitivity analysis BD shows a balanced pattern of positive and negative influences while the other predictor variables show mostly either positive or negative effects. In the literature, effects of BD were only found for Cu and Pb. The found positive effects (even though not significant for Pb) are thus confirmed \cite{Kabata-Pendias2010}. \\

The effects of BD and CEC are mostly antagonistic except for As and S but mostly only one variable is significantly affecting the elements. For all elements, the effect of CEC is stated as positive in the literature \cite{Kabata-Pendias2010, NavasMachin2002}. The sensitivity analysis confirmed these relations. CEC does not effect Se in topsoil horizon but has a positive influence in A horizon and a negative in C horizon. The overall effect of CEC is stronger in A\&C horizon then in the topsoil. A stronger effect was expected in the topsoil because of the higher SOC content which strongly enhances CEC \cite{BlumeBruemmerHornEtAl2010}. We suspect that this could result from an overestimation of the importance of CEC in the models. CEC data was only available for the topsoil and thus the input CEC values in the models were higher then they occur in the environment. The same effect might also apply to BD.\\

Clay has always a positive effect on element concentrations but the effect on Hg is not significant. This is also consistent to the literature \cite{NavasMachin2002, FlemmingTrevors1989, Kabata-Pendias2010, SokolovaAlekseeva2008}. The sorption of Hg onto clay is limited compared to the other elements \cite{Kabata-Pendias2010}. Clay shows the least influence in C horizon which is reasonable due to generally low clay contents in the C horizon \cite{BlumeBruemmerHornEtAl2010}. The clay content was often not of major importance in the model creation but has a strong effect on most elements. It can therefore be reasoned to be a very effective retention mechanism for most elements. Clay is very vulnerable to surface runoff due to agricultural processes. Gentle soil treatment processes could thus raise trace element concentrations.\\

ET is a significant driver of all elements. The influence of ET is mostly negative and only Se is positively driven in all horizons while Pb is positively driven only in C horizon. There is no effect of ET on Pb in the A horizon. The negative effect of ET on most elements can be explained by the uptake of elements by plants. High ET requires sufficient amounts of biomass an thus a high photosynthesis rate. The passive uptake mechanisms of the plants then reduce element concentrations \cite{Kabata-Pendias2010, McNealBalistrieri1989}. Pb is known to be very little bioavailable \cite{Kabata-Pendias2010} and thus ET has no negative effect. Se on the other hand is positively influenced by ET because its concentration in plants is low but it is highly sorbed onto SOC which contents are high when there is a lot of biomass \cite{Kabata-Pendias2010}.\\

SOC is a known adsorbent for all elements examined \cite{MandalSuzuki2002, BalasoiuZaguryDeschenes2001, ImpellitteriSaxeCochranEtAl2003, FlemmingTrevors1989, Kabata-Pendias2010, Schuster1991, SokolovaAlekseeva2008}. The found positive effects on element approved this but only Hg, P, Pb, S and Se were significantly influenced in the sensitivity analysis. SOC has the most influence in the topsoil and A horizon whereas it is not a strong driver in C horizon. This was expected because SOC concentrations are generally highest in the topsoil and lowest in the C horizon \cite{BlumeBruemmerHornEtAl2010}.\\

Temperature has a negative effect on P and Se and also a weak negative effect on all other elements except Ca. This is surprising as temperature is an important variable in the models. We suspect that temperature was not used as as an independent variable in the models but was included in a combination with other variables as an indicator of weathering. These results imply that a rise of temperature due to climate change could reduce concentrations of P and Se and thus worsen malnutrition of these elements.\\
