I was starting to feel a little anxious as I approached the shores of Dongting Lake in China's central Hunan province. From a distance, I easily spied the country's second largest freshwater lake. As I approached, waves lapped up on the shore, breaking near the barriers separating the lake from the nearby walkway. As I peered over the barriers and gazed further, I saw clumps of green protruding from the water. They were tree tops. This wasn't exactly the scene I was expecting.
Dongting Lake has been reported as a lake in crisis. Dropping water levels have sent alarm-bells ringing in scientific and environmental circles, as the area of the lake has reportedly dropped by nearly 50 percent in the past 70 years. What I was witnessing however appeared to be the opposite. One fact was certain, this was a lake in an incredible state of flux.
"You've come at a time of flood," reassured Liu Juxiang, as we chugged along in her compact water-taxi, used to ferry goods from the lake's shore to waiting ships on the water. "Three months later, the water will become less. Many places have no water. The water could become one kilometer wide in the dry period, while it's two kilometers wide now."
Lying just off the Yangtze River, Dongting Lake has served as an essential buffer zone in times of flood in the region, receiving excess water from China's mightiest river and protecting many downstream. In recent decades however, the lake has shrunk dramatically, causing scientists to begin investigating the causes of these changes and their effects on one of the country's most important lakes.
"150 years ago, it was 6,250 square kilometers. 60 years ago, it was 4,350 square kilometers. Now, it's 2,600 square kilometers", commented Jiang Yong, on the area of the lake. Mr. Yong, an ecologist who has spent the past 18 years studying the province's largest body of water, has become increasingly concerned about the trend. "Mud and sand keep silting up in the south of the lake. Therefore the capacity is becoming smaller. The silted mud becomes new land, which becomes islands and beaches which people then live on."
It was a simple process to envision in action. Dongting Lake is fed by not only the Yangtze River but also by a number of other smaller tributaries. Combined, they have led to the flushing of sand and mud into the lake. As China's burgeoning population grows, the demand for land is increasingly high. Opportunities for land reclamation are hard to pass on.
As our water taxi bobbed across the lake, we weaved around huge ships carrying large conical piles of sand. Pointing to one of the looming hulks which dwarfed our boat, Mrs. Lu reminisced about the changes she had seen on the lake. "In the past, there were 20-30 sand ships in the lake. Now there are more than 300. They dig sand every day, every month, every year but there [is] still sand here. I don't know how fast the sand grows, but it definitely grows."
As I hopped off Mrs. Lu's boat and strolled along the lake, piles of sand could be spotted on nearly every ship passing by. "Some of the ships dredge the lake to make the transportation smoother. If the sand silts up at the bottom, ships will not be able to pass through the lake easily. Others are doing it for raw material for construction", explained Jiang Yong. "Too many ships on the lake will disturb the life of animals in water, like dolphins. We have river dolphins here, and sand digging will affect their lives."
Fish restaurants line the streets of Yueyang, a town lying on the northeast shore of the lake. They advertise a myriad of aquatic creatures for sale to the hungry tourists who descend on the town. "Fish has become a brand of Dongting Lake. People have the idea that eating fish is a must when you come to Dongting," said Jiang Yong. "Therefore the demand is larger and larger."
Lake shrinkage has exceeded the fish's ability to adapt to their dwindling ecosystem, resulting in fewer and fewer fish. Coupled with pollution, only smaller species remain in what was once a lake teeming with larger ones. Now, most of the bigger fish in the town are brought from other lakes, as the numbers have shrunk so much in Dongting itself. Overfishing has caused many fisherman to abandon their traditional ways of life for more lucrative and easier jobs on passing ships. Government sponsored programs have also recently encouraged fishermen to leave the water and seek land-based jobs.
"When the demand of the people goes up, the quality of the environment will go down", was one of Jiang Yong's final comments to me. This thought sat with me as I strolled along the lake shore one final time. Crowds had gathered to play in the waves, now lapping over the barriers and spilling onto the walkway. Yet the water's temporary advance failed to hide the severe problems the lake currently faces.