Does climate change influence the availability and quality of reindeer forage plants?

The northward and upward movement of the tree line and gradual replacement of lichens with vascular plants associated with increasing temperatures and nutrient availability may change the reindeer pastures in Northern Fennoscandia. The productivity of reindeer forage will most probably increase, but their protein (nitrogen) concentrations may decrease because of higher temperatures and CO2 concentration. In the long term, the nutritive value of forage will depend on the mineralization rate and nutrient uptake from the soil. Enhanced UV-B is likely to increase the concentration of phenolics, decreasing forage quality and choice, but reindeer may adapt to increased phenolics. Increased winter precipitation, the occurrence of ice layers, deeper snow cover, and the appearance of molds beneath the snow cover may reduce the availability and/or quality of reindeer forage, but prolongation of snowless periods might have the opposite effect. The net balance of negative and positive effects will vary regionally depending on the climate, bedrock, vegetation, reindeer herding systems and socio-political factors. Multidisciplinary research is needed most importantly on the effects of the changing winter climate on reindeer forage, and the effect of modified forage quality on reindeer physiology.