Tree-ring climate response of two Larix species from the central Nepal Himalaya

Changes in the global temperature and precipitation regime have been significantly driving species responses, notably in sensitive areas such as the Himalayas. By conducting a study at two high altitude (3200–4100 m) valleys (Langtang and Tsum) situated in the central part of the Nepal Himalayas, we presented tree-ring width site chronologies for two Larix species (Larix griffithii and L. himalaica) for the first time. The longest chronology spans from 1771 to 2015 AD and showed a recent decline in the growth of Larix species in both sites, controlled mainly by drought. Tree growth showed a negative response to temperature and a positive response to precipitation, indicating that moisture stress is limiting the growth of the species. Based on the Larix ring width chronology statistics and climate response results, these species have good potential for past climate reconstruction such as temperature, rainfall or drought indices. Also, the study revealed that the Himalayan endemic Larix species investigated are promising for tree-ring based multi-aspect environmental change studies in the future.