Salix tetraspema (Peling-shing), the last remnant Salix species

Peling tsho (wetand) where Salix tetrasperma stands. Pic: Bhutan For Life

KARMA CHIMI

Thimphu

The last remaining stands of Salix tetrasperma in Bhutan are found in Dechhenling gewog, Pemagatsel. This species is locally referred to as Peling-shing.

Peling Tso (wetland) covers an approximate area of 34.219 hectares (85.547 acres) and is located along the lower slopes at an altitude of 950 m. The wetland serves as a natural reservoir and source of Peling-chhu, which is the only perennial stream in Dechhenling gewog.

Peling Tsho (wetland) is dominated by Salix tertrasperma, a deciduous broad-leaved species and it is is located within the 3 chiwogs of Gonpawoong, Shinchongri and Kholomri in Dechhenling gewog.

According to Dr. Pema Wangda, Executive Director of Bhutan For Life, the biodiversity assessment of Peling Tsho (wetland) was initiated around 2010 and the team identified Peling-shing as Salix Tetrasperma in 2014-2015, a new record for Bhutan.

Salix tetrasperma belongs to the family of Salicaceae which is a deciduous undershrub or a small tree found in various countries such as India, China, Malaya Peninsula and Archipelago.

The medium-sized tree is native to swampy and damp areas, sheds its leaves at the end of the monsoon season. The bark has deep, vertical fissures and is tough. The leaves are 8–15 cm long and lance-shaped or ovate-lance-shaped.

The water discharge slowly decreased and the local communities of Dechhenling were worried that the lake may dry up completely. The study conducted by the relevant agency found out that the underneath of the Peling-shing wetland serves as reservoir of water where Salix tetrasperma plays an important role.

Recent developmental activities and intensive farming along the lower slopes of the wetland are found as some of the factors affecting the condition of the wetland.

Tshetor, a village elder said that during his younger days, the wetland used to be vast and the villagers were even afraid to go near the wetland after dark. But today the tsho has significantly degraded over time.

He adds that the government has intervened in the right moment and knew about the drying up of the lake. He said villagers can now take necessary measures to conserve and protect their sacred tsho.

Tshetor said the villagers are ready to take actions and conserve the lake in accordance with the plans initiated by government.

In other regions of the world, the plant is used ethnopharmacologically to cure conditions including diabetes, fever, piles, epilepsy, rheumatism, swellings, bladder stones, wound, ear discomfort, dysentery, cough, and cold, but the locals have only ever used the plant to construct small temporary huts.

Dr. Pema Wangda said new records such as this particular species to Bhutan shows that Bhutan is host to many new plant species that are yet to be discovered.

He added due to the constitutional mandate and far-sighted vision of the monarchs, Bhutan has intact and pristine environment which harbours various plant species that are still yet to be discovered.

However, the challenges according to Dr. Pema in conserving this species was due to the lack of knowledge, capacity and understanding of peling shing (Salix tetrasperma) and its importance in water conservation and wildlife habitat.

“If we don’t realise the importance of such species in conserving water, we may lose water source for the lower or downstream communities and for the rich biodiversity,” he said.

Further, the assessment found that the wetland plays an important role in supporting the livelihoods of the communities and also harbours diverse habitats for plants, animals and aquatic diversity.

The study also added that the change in land use practice from traditional to conventional type and other developmental activities including farm roads and transmission lines are some of the pressures that affects the management of wetland.

The study was timely to intervene and propose for sustainable management of the wetland based on scientific research findings.

Experts say that high priority should be accorded to the conservation of surrounding forest in order to manage the wetland ecosystem. “Understand the ground water recharging mechanism between surrounding buffer forest and rainfall during the monsoon is of importance,” the study reveals.

It was found the surrounding buffer forest play an important role in sustaining the live of wetland rather than controlling the grazing by fencing the wetland.

The study reveals, “The surrounding evergreen broad-leaved forest plays an important role as a buffer forest (natural infrastructure) to help in recharging the wetland during the rainy season by slowly filtering (root systems, fallen leaves and organic matter on the forest floor) the surface runoff rainwater that flows from the hills into the wetland.”

Therefore, the experts commend it is necessary to take into consideration of all the stakeholders in managing the wetland ecosystem particularly looking at the traditional farming practices which forms as an important component of holistic wetland management.

The local myth surrounding the lake or the wetland has also helped in preserving the environment as the local believes that the wetland or tsho has spiritual significance and cannot be disturbed.

Locals further shares that although the stream is not used for human consumption. The communities from 120 households residing in 3 chiwogs with a total population of 2793 are the primary beneficiaries and resource users of the wetland.

According to the study, the lowland wetlands are found as important source of water and habitats for variety of life-forms and recommended to be declare as a wetland of national importance.