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Soil organic matter (SOM) is a multifunctional key component of the soil, also important for the sustainable crop production. SOM levels in arable soils are strongly affected by soil management practices specifically by the tillage. The first study of this book describes the impacts of two different tillage intensities on carbon and nitrogen dynamics of an arable soil from a long term tillage experiment Garte Süd, Germany after 40 years. The sorption properties of SOM strongly affect the cation exchange and sorption reactions in soil solution. Less is known about the sorption of nutrient cations as most of the sorption studies focus only on heavy metals and organic pollutants. The second study of this book envisages sorption dynamics of nutrient base cations (Ca2+, Mg2+, Na+, K+) of an arable soil from a long term fertilization field trial at Darmstadt, Germany. SOM is considered as a key translocator of persistent organic pollutants (POPs) in the environment. Aggregate fractionation of SOM could be advantageous over bulk soil analysis in terms of better eco-toxicological assessment of POPs. The third study included in this book quantifies and compares the distribution of POPs in water stable aggregate fractions and within bulk SOM of two British forest sites.

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