Diverging climate trends in Mongolian taiga forests influence growth and regeneration of Larix sibirica

Central and semiarid north-eastern Asia was subject to twentieth century warming far above the global average. Since forests of this region occur at their drought limit, they are particularly vulnerable to climate change. We studied the regional variations of temperature and precipitation trends and their effects on tree growth and forest regeneration in Mongolia. Tree-ring series from more than 2,300 trees of Siberian larch (Larix sibirica) collected in four regions of Mongolia’s forest zone were analyzed and related to available weather data. Climate trends underlie a remarkable regional variation leading to contrasting responses of tree growth in taiga forests even within the same mountain system. Within a distance of a few hundred kilometers (140–490 km), areas with recently reduced growth and regeneration of larch alternated with regions where these parameters remained constant or even increased. Reduced productivity could be correlated with increasing summer temperatures and decreasing precipitation; improved growth conditions were found at increasing precipitation, but constant summer temperatures. An effect of increasing winter temperatures on tree-ring width or forest regeneration was not detectable. Since declines of productivity and regeneration are more widespread in the Mongolian taiga than the opposite trend, a net loss of forests is likely to occur in the future, as strong increases in temperature and regionally differing changes in precipitation are predicted for the twenty-first century

Comments on the Red Data Book of endangered plant species of Mongolia

A more detailed categorization is proposed for the future Red Data Book of endangered plant species of Mongolia. While the most recent Red Data Book for Mongolia has its own scale, a future edition should adopt the international categorisation of the International Union for the Conservation of Nature (IUCN). As a basis for a more detailed assessment of the degree to which plants are endangered, research on the flora of Mongolia should be intensified by elaborating monographs of all 16 phyto-geographical regions. So far, such monographs have been published for four phyto-geographical regions: Khovsgol, Khentii, Khangai, and Eastern Mongolia. The responsibility of Mongolia for the global conservation of a given species should be assessed. Mongolia is responsible for those species which have their main distribution in Mongolia or for which Mongolia is part of the range center