Higher growth of grasses due to N-availability, toxicity is much higher, dominant nitrophitic species

Soil acidification:

Depletion of base cations, higher Al³⁺, Changes in species composition (more nitrophitic and acidophitic species, fewer rare), damaged buffering.

b). Describe the changes in soil chemistry that were caused by the enhanced NH₄⁺ deposition.

N deposition may have severe effects to soil. Usually soil and water have a good feature to maintain pH level by buffering but sometimes when a level of acids becomes much higher than usually pH level decreases by this way. It causes a chain of consequences such as weakening ANC, the loss of nutrients from the top of soil (degradability organic matter), higher Al³⁺. The ability of high amount of grasses will cause a high level of nitrogen uptake.

c). In order to restore these ecosystem a number of management options are possible. Provide 4 of these options and explain their importance. (Boxman/Bobbine).

Restoration after N eutrophication: Options: More efficient N removal via adjusted management (moving time, frequency, grazing). Sod-cutting.

Restoration after soil acidification: Options: Via natural recovery (weathering, very long-term process in these dry ecosystems), via extra inputs of buffering substances (base cations), liming (after top soil removal, catchment liming, increased influence by buffered groundwater.

8. As shown in the film “hope in a changing climate” it is very well possible to restore large landscapes. Give 3 major ecological goals to achieve and explain their importance (Boxman).

9a. List three causes for the decline in heathlands and grasslands in western Europe and provide a management measure for each of these three that counteracts the negative effects.

Fertilizer was relatively cheap and very effective! 1) disappearance of traditional agricultural systems 2) population growth resulted in industrialisation 3) pollution! Nitrogen, Sulphur, heavy metals etc àacidification + eutrophication.

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