Evening lecture by Wim de Vries organized by the Haarlemse Chemische Kring.
The chemistry of nitrogen in the soil
Summary
This presentation focuses in particular on the consequences of a disrupted nitrogen cycle caused by excessive emissions of ammonia and nitrogen oxides (in conjunction with a disrupted sulphur cycle) on soil acidification and the nutrient balance in non-agricultural land (particularly forest land). The processes that collectively lead to acidification, including mineralisation, nitrification and denitrification, are discussed.
Buffer processes that neutralise acid production are then discussed, including the release of cations through weathering and desorption of, amongst others, calcium and aluminium, and the sequestration of anions through, amongst others, immobilisation and adsorption of nitrate and sulphate. The role of buffer mechanisms across different pH ranges is examined. The effect of nitrogen accumulation and acidification on the balance of nitrogen relative to potassium, calcium and magnesium is discussed, along with the possibilities for restoring this balance through measures such as liming and the addition of rock flour.
Furthermore, comparable acidification processes occurring in agricultural soils are briefly discussed, along with how these can be managed through measures such as fertilisation and liming. The effects on forest soils will be illustrated specifically for the Netherlands, and those on agricultural soils for China, where acidification in agriculture is a problem in relation to crop production
Biography
Wim de Vries is a professor at the Earth Systems and Global Change Chair Group at Wageningen University, where he holds the chair in ‘Integrated Nutrient Effect Modelling’. His research focuses primarily on the effects of fertilisation on crop production, air, soil and water quality. The emphasis is on the cycles of nitrogen, phosphate and carbon, and the consequences of changes in these cycles for nature – such as forest growth, carbon storage and plant species diversity – and the environment, such as soil acidification.
Wim de Vries has authored or co-authored more than 600 publications on the above-mentioned topics, including more than 200 in international journals.
Wim de Vries - Google Scholar Citations
Guests are very welcome.
Please let us know in advance if you plan to attend.
Send an email to s.groenendijk@planet.nl.
