Tarim poplar forests at risk

Guest post by Wang Haotong, trainee journalist at chinadialogue in Beijing

Shayar County in the Tarim River basin, in the Xinjiang Uigur Autonomous Region, is home to more than 133,000 hectares of the world’s best-preserved and largest natural Euphrates poplar forest. The area is sometimes known as the “Tarim Poplar Township”. But according to reports, changes in the river flow mean that 66,000 hectares of Euphrates poplar tree groves along the banks of the river valley are not being irrigated – and are now on the verge of destruction.

The Euphrates poplar is the only tree species that can establish a forest in the desert sand. It is comparable to the ginko, sometimes called a “living fossil”. Poplars stabilise the ecological balance of desert river zones, fix the sand, adjust the climate and create fertile forest soil. These trees serve as an important natural bulwark for agriculture and pastures in desert regions. At the same time, the Euphrates poplar is a valued tree that has been important in ancient economies and cultures.

Most of world’s Euphrates poplars grow in China, and of those, more than 90% grow in Xinjiang’s Tarim Basin. However, even the Euphrates poplar might wither away due to a lack of water.  In order to adapt to the dry climate, most poplars grow near water. But shifting sand dunes mean there are frequent changes in the desert river flow. Changes in the river course, improper water resource development and over-use have slowly exhausted the water source, and the Euphrates poplar groves that cover the original river course have come to suffer because of lack of water.

As a result of these changes in the course of the Tarim River, there are reports that in the five-kilometre vicinity of the southern border of Shayar County, tens of thousands of poplar trees have wilted due to lack of water. The grotesque shapes of the dead trees have led the area to become known as “the monsters forest”. According to statistics from the Xinjiang Forestry Bureau, in the three decades between 1970 and 2000, the original Euphrates poplar forest area in the Tarim Basin has shrunk by one-third.  The forest area has been drastically reduced from 520 000 hectares to just 350 000.

When interviewed by China Environment, Song Lixin, the director of the Shayar County Forestry Station, commented on the damage to poplar forests. He said that along both banks of the old river course 100,0000 hectares of poplar forest is now parched land, any further growth is inhibited, and the existing trees are facing obliteration due to long-term  water shortage. Unless necessary restoration and protection measures are taken, the Euphrates poplar trees along the old river course will perish. If that happens, the Taklimakan desert will expand and encroach upon oasis areas with serious implications for the local environment. Another completely new “monster forest”, more than 100,0000 hectares in cover, could appear within the Shayar Country boundaries.

Water availability is the key factor in preserving the Tarim Euphrates poplar trees.  However, water resources are limited and the Euphrates poplar restoration program has not yet been approved. Furthermore, according to Song Lixin, even if more funds were available, water shortages could still be a problem.  “There is a fixed amount of water in the Tarim Basin,” he notes, and  “if some of the water is diverted to irrigate the old river bed this may just move water shortages elsewhere”. To date, there has been  no scientific assessment examining exactly how much water would be required annually to provide enough to irrigate the old river course.

Translated by chinadialogue volunteer 凯利