To the Three Gorges Dam – August 8th / 三峡大坝之旅
Post from Team Otter August 8th
Early in the morning we boarded dragon boats and went along the river to the Jiuwan stream gorge. We had been looking forward to racing each other to the gorge, however, much to our dismay we were not allowed to paddle, relying instead on the outboard motor. “Ah, this is so lame!” Professor Wang youthfully declared as his “private” boat whizzed past us and left us in the wake of his magnanimity. As we continued between the steep cliffs of the river our guides pointed out to us two hanging coffins; constructed by the Ba people their presence attracts tourist and this is used as supplementary tourism income for the villagers operating the park. We soon arrived at the gorge and were pleased to find it such a beautiful area and some of our peers were fortunate enough to see three Golden Macaques. In spite of this sighting, the area was largely devoid of wildlife such as amphibians (as Professor Lougheed pointed out) and birds; a reminder of the extreme ecological impact of The Three Gorges Project. Before the dam was built the stream had had a depth of two meters. Now the depth has increased to one hundred and sixty meters. Such a change means that the aquatic and riparian environments have been irrevocably altered.
At midday we arrived at The Three Gorges Dam. The air was thick with smog, the humidity was impossibly high, and the temperature was scorching- another beautiful day on the Yangtze River. The dam itself is so large that it is a marvel of engineering on scale with the pyramids of the Maya or The Coliseum of Rome. The dam is almost three kilometers in length and contains thirty-two turbines for the generation of electricity. For the movement of ships across the dam there is a five-lock system for larger boats and an elevator for smaller vessels is nearing completion. The lock system takes approximately four hours to pass and the elevator is expected to take around one hour. The generators produce electricity in the range of 1.7 million kW each and the whole dam provides about 84.7 billion kW. This constitutes about three percent of the electricity usage in China.
We learned that The Three Gorges Dam plays an important role in flood control of the middle reaches of the Yangtze River. Due to the dam, The Yangtze River is now like several lakes rather than a river. It is impossible for some fish to migrate, that is to say, there are no fish ladders to allow them to overcome the dam. It is said that we have lost over 90% of the fish species in Yangtze River since The Three Gorges Dam was built. What’s worse, this so-called ‘lakes’ are quite deep, so the water quality is quite bad under the surface without photosynthesis. In order to provide as much electricity as possible, only water in the deep place which bears high water pressure can flow through the dam, which means we only let the bad quality water flow down to the downstream of Yangtze River.
Upon leaving The Three Gorges dam we left behind the mountainous, red clay-soil landscape of greater Chongqing for the flat, swampy province that is Hubei. This region places great importance in agriculture and aquaculture for its livelihood. On the way to our nightly stop-over in Jingzhou we saw unending lotus swamps and rice paddies and ponds for fish, crab, and shrimp. It was interesting to see that the primary source of heavy labour was not the tractor, but the water buffalo.
After dinner, two of us who comes from Fudan University gave their presentations, one entitled Interplay Between Geography and Human Activities by Qinhua Yan and the other entitled Urbanization in Shanghai invasive species in Jiuduansha Wetland and degradation in JIanguan Wetland given by Zhengni Wang. We focused on the human impact on Dongting Lake, which is causing severe decrease in lake size and eutrophication. As a big city closed to the ocean, Shanghai suffers from invasive plants not only in the aquatic ecosystem but in terrestrial ecosystems as well. The presentation gave several possible solutions to this problem, and warm discussion ensued about the possibility of these plans or projects lasted for a longtime.
在晚餐之后，两位来自复旦的同学做了她们的课题陈述，分别是来自严钦骅的“地质与人类行为的关系”和来自王政旎的“长江下游的植物多样性”，我们对于湖泊 面积的锐减和水质的富营养化进行了深入探讨，并且举出了多个湖泊的例证。作为一个沿海大城市，上海在各个生态系统都遭受了生物入侵的威胁。这些陈述对解决 这些问题提出了很多方法，并且这些探讨热烈了很很长的时间