The changes in snowfall pattern over the years in Himalayas are affecting the life cycles and distribution of alpine floral diversity in the region.
According to a study conducted in Beas Valley by ecologist and environmentalist TK Roy, it has been found that alpine floral diversity in the Valley has been declining and some of the rare species are disappearing due to the impact of climate change.
Beas Valley is located between Dhundi and Beas Kund in Kullu district at the elevation between 9,000 and 15,500 ft height. The valley is a rich natural habitat of more than 100 species of seasonal Himalayan alpine flora, especially alpine herbs including rare medicinal plants, which appears and blooms only in the month of May-July for reproduction and also, plays a key role to maintain fragile Himalayan ecosystem.
Talking to The Pioneer, ecologist TK Roy, who is also the coordinator of the Asia Waterbird Census (AWC) said, “Due to climate change, the unusual, unseasonal, late and heavy snowfall is witnessed in the Himalayas as studied in the Beas valley during last five year’s field studies (2010-2014). This year recorded heaviest ever, unseasonal and late snowfall even in the month of May.”
“As a result, most part of the valley remained snow covered to get exposed to the ground habitat till date and fragile alpine vegetation i.e. seasonal alpine herbs could not grow up to bloom for reproduction. Only about 40 herb species of major families are blooming in few smaller open patches of the valley.
These are herbs of Primula family including Primula denticulate, Primula atrodentata, Primula glumerata, Primula reptans, Primula primulina, Primula macrophyla; herbs of Buttercup family, Poppy family; herbs of Rose family like Potentila cuneata, Potentila eriocarpa; Stonecrop family like Rhodiola wallichiana and Rhodiola bupleuroides; traditionally used herbs like Fritilaria roylei, Allium humile, to name a few,” he said.
The changing climate pattern, which is causing extreme weather conditions like heavy and late snowfall has today become a matter of concern for experts. The climate change over long periods has significantly affected the vegetation structure, community composition and ecosystem dynamics in Beas valley. As the fragile alpine vegetation especially floral diversity has been declining while several species have disappeared disrupting the alpine ecosystem.
According to the past studies, the alpine plants are sensitive to climate change and are thus likely to show responses to climate change in the past few decades. Roy said, “Besides climate change, the local threats are also adversely affecting the alpine floral diversity of the Beas Valley.”
The ecologist said, “While the seasonal herbs start grows to bloom once the valley habitat exposed from snow during the peak blooming season in summer-monsoon, cattle grazers reach the valley with their thousands of sheep/ lambs for grazing for the season and clean the area by grazing the entire alpine vegetation of the valley without leaving chance of seasonal reproduction.”
“Further, the seasonal adventurers especially the trekkers and campers are highly polluting the alpine vegetation by leaving non-biodegradable garbage openly in the valley,” said Roy.
“At present, no monitoring is done by the concerned Forest and Wildlife authorities for conservation and protection of this fragile picturesque valley. If such local threat continues with climate change, fragile alpine vegetation of the valley and biodiversity will be disappearing to cause natural ecological disasters in near future,” he added.
According to the past studies, while scanty snowfall and rising temperature in the past decades have sparked the possibilities of fast shrinking of glaciers in Himalayas, heavy and unseasonable snowfall in last few years are now also changing the vegetation ecosystem. In Indian Himalaya region, particularly in alpine areas, changes in snow pattern and temperatures are affecting the distribution and phenology of some plant species.
Several studies in the Himalayas by experts have also pointed out that during the last century, the mountains have experienced continued warming above the global average. And, the biological responses of alpine plants to climate change have shown increasing climatic stress for many alpine plant species.