Phurpa Lhamo | Punakha

If blue pine is encroaching into spruce, maple and birch forests, what does it indicate?

Experts say this is a sign of impact of climate change.

Blue pine, which usually is confined to the lower elevations, can now also be found in the fir forest, between 3,400 metres and the tree line.

“We see that blue pine forest is now encroaching the alpine region,” said Dr Jigme Tenzin (PhD), deputy chief forestry officer with the Watershed Management Division, Department of Forests and Park Services.

He added that Bhutan’s alpine region has medicinal plants such as gentiana urnula, fritillaria spp., and cordyceps sinensis.

Because people depend on cordyceps for an income in the higher region, there would be an impact on the livelihood of the people due to the shift in the eco-system, Dr Jigme Tenzin said.

He added that the upper limit of the evergreen broad-leaved species was also correlated with winter temperature, which means as the temperature increases, the upper limit of the evergreen broad-leaved species shifts upwards.

This impact on the ecosystem was related to two major factors—temperature and precipitation.

Since the 1960s, the global mean surface temperature has increased by 0.6° Celsius (0.4-0.8° Celsius).

Dr Jigme Tenzin said that the trends indicate that shorter, heavier precipitation could be experienced in future.

These observations were presented at the Bhutan Himalayan Climate Studies (BHCS) Science Dialogue, series II held in Punakha yesterday.

Another impact on the forest was the increasing outbreak of bark beetle in Bhutan due to increasing temperature.

“We’ve seen 39 incidences already,” Dr Jigme Tenzin said.

Reports have also shown that 2.3 percent of Bhutan’s spring water had dried up; 34.1 percent was drying.

At the discussion, old trees emitting more carbon dioxide than they sequestrate, and REDD+’s (reducing emissions from deforestation and forest degradation in developing countries, and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries) results based payment scheme were also raised.

Dr Jigme Tenzin said that Bhutan’s carbon emission was 0.5 million (M) and sequestration rate was 8M. “If you reduce emission, you get paid for what is reduced. In order to get paid, if we reduce Bhutan’s carbon emission to 0.1M, we would be paid for 0.4M. But Bhutan is a developing country and that isn’t possible as emission is going to increase.”

Dr Jigme Tenzin said that, although it was believed that the old trees emit more carbon dioxide than they sequestrate, Bhutan was safe as its forest is quite young.

Themed “Climate change on mountain livelihood and food security”, the dialogue was held in the College of Natural Resources in Punakha.

The discussions and presentations will be available on the BHCS website.