Mazsalaca pine forest ecosystems

Mazsalaca pine forest site is located in the North Vidzeme Biosphere ­Reserve near a small town – Mazsalaca (57°53’ N; 24°59’ E).

It includes Scots pine (Pinus sylvestris) sites of three different ages – young stand (30–40 years old), middle age stand (50–70 years old), and old stand (150–200 years old) on sandy podzol soils with 2–30 cm thick organic horizon.

The forest floor vegetation is dominated by Vaccinium ­myrtillus, V. Vitis-idaea and Melampyrum pratense. The moss cover consists mainly of Hylocomium splendens and Pleurozium schreberi.

Regular studies have been performed on various forest ecosystem components: soil chemistry (heavy metals), tree stand (pine needle chemistry and necroses), forest floor vegetation, epiphytic lichens, mushroom fruiting bodies, litter decomposition intensity and various groups of soil fauna.

Decrease in heavy metal pollution of soils resulting from industry decline in Latvia, as well as with­drawal of Soviet army bases, and gradual forest ecosystem recovery was observed after the restoration of independence of Latvia in 1991. A significant reduction of species richness and changes in community structure of soil mesofauna were observed against the background of climate warming.