Alpandino :: Alpine plant nutrition :: Responses of vegetation to variable nutrient supply

1 - Glacier forefield receiving additional nutrients

An almost barren glacier forefield received slow release fertiliser. Look at the result!

2 - Glacier forefield community before and after fertiliser addition

Nutrient addition causes species to become winners and losers. Slow growing cushion plants (Fig. 3) and small rosette species become overgrown by vigorously responding grasses and herbs (Fig. 4) when nutrients are added to a sparse glacier forefield community.

5 - Festuca orthophylla tussocks grow faster when receiving llama dung (a young, vigorous tussock in the front).

Dry llama dung collected from overnight kraals and spread around tussock grasses enhances growth, but also stimulates nitrophyllous herbs such as Urtica sp.

6 - Androsace cushion, a closed compost heap with rich microbial life in an otherwise barren landscape (2500 m, Wildstrubel glacier, Swiss Alps).

On very nutrient (humus) poor substrates, plants are successful if they retain the nutrient capital they acquire year by year. The cushion form prevents the loss of dead biomass (leaf litter) through wind and water. A "private" compost heap creates a microcosm for a rich decomposer community in an otherwise barren environment.

7 - The sticky Pinguicula leaves trap insects which are digested by enzymes excreted by leaf glands.

On very poor soil, some species even trap insects and digest them to improve their diet. Insectivorous Pinguicula species are found both in the Alpine and the Arctic.