Oct. 24, 2017


Decade River Profect 2010 (6) Global Climate Change in Yunnan

Global Climate Change in Yunnan
Reported by: Wang Yongchen

 On November 29 2010, during River Decade 2010, we headed for Xiaowan Hydropower Station on the Lancangjiang River. As we set out in the morning, the first segment of the Lancang that came into view was the Xiaowan Hydropower Station reservoir. A great river had become a reservoir, but the biggest difference was the calm water of the reservoir.

 In the morning, the river was calm and the clouds in the sky were drifting around.


 
Clouds travelling between mountains


 
A great river that cannot run


 
The river flanked by mountains after it became a reservoir

 

In spring 2010, from the Premier to the populace, people were worried about the severe drought in southwestern China. I believed that natural disasters resembled human diseases in the way they occur after a process of accumulation rather than suddenly within one or two days. The climate change of a region tends to closely correlate with changes in the local ecosystem.

In recent years, the overall ecological condition of China has deteriorated: low rate of forest cover, degradation of forest vegetation, pasture degradation and intensified desertification caused by overgrazing, the deteriorating ecological environment of great rivers such as the Yangtze and Yellow rivers, as well as the shrinking of important lakes and wetlands. Among the 640 species listed in the  International Convention on Trade of Endangered Wild Flora and Fauna, 156 are found in China, accounting for one fourth of the total.


 
The scenery of Lancangjiang River which remained autumnal in late November
 


Eucalyptus trees growing on the mountain.

 


The locals refer to the flower as “plane grass.”

This year marks the fifth year of the River Decade that started in 2006. Along the road, we saw many banners about strengthening development on the western part of China while noting current conditions. In western China, mines were being operated, rivers were being exploited, pristine forests were replaced with eucalyptus and rubber trees, and the wilderness had been removed to make way for towns.
Helping the people of western China to overcome poverty is not a cause for criticism. Yet the ecosystem there is so fragile and the species so precious. How did the people of western China get on with nature? With all of the mining, development, planting and construction, have we seriously studied the relationship between people and the environment in the western region?

 


Xiaowan Hydropower Station
 

 
A hydropower station and two mountains
 


Photographing on top of a mountain

The introduction to Xiaowan Hydropower Station that we read on the internet is like this: Located at the lower reaches of the Yangbi River which is the common boundary of Nanjian Yi Autonomous County and Fengqing County of Yunnan Province, Xiaowan Hydropower Station is the key project of the Lancang River. Being the upper station of the Manwan Hydropower Station, it’s 265 kilometers away from Kunming. The height of the dam is 300 meters, the height of the highest waves 250 meters, the total storage capacity 15.3 billion cubic meters, the effective storage capacity 11.3 billion cubic meters, the installed capacity 4.2 million kw, guaranteed capacity 1.85 million kw and it can generate 19.17 billion kW•h of electricity each year”.

The cause of the drought in southwesternern China this spring is still to be identified through full investigation, but according to the information revealed, we could see some traces of human activities. While fighting against the drought, we need to pay careful attention to these factors.

For example, to obtain economic benefits, some provinces in southwesternern China are deforesting the virgin forests and planting planting densely rubber trees and eucalypti. However, these two species of trees which are fast growers and provide good harvests are vividly called “pumps”, as planting them in large areas can lead to a decrease in groundwater levels due to their poor ability to store water. In addition, eucalypti are also dominating and opportunistic. Wherever eucalypti grow, other species gradually retreat, resulting in bare ground with nothing other than eucalypti and irreparable damage to the ecology. Statistics show that in Xishuangbanna Yunnan, where large areas of rubber trees are planted, the number of foggy days each year decreased by 30 days after the 1980s and now that has decreased by 60 days, a sign of the decrease in humidity there and the change in regional climate. At present, the area of rubber trees in Yunnan has reached three million mu, while the planted area of eucalypti has been up to 30 million mu. Is this enormous change to the ecological system the trigger for the drought?

 

 


The differences between mountains where rubber trees and native plants grow
 


The plant “Magan” growing all over the mountain

In fact, according to media reports, the forest coverage rate in southwestern China is more than 50%. An internationally accepted theory indicates that if the forest coverage rate of an area is more than 40%, ecological problems such as drought and flood would not happen there. That is because a 40% rate of forest coverage can ensure a large amount of water is stored in the soil as well as the rivers. Thus, no disaster like the 2010 severe drought in southwesternern China would happen even without rainfall for several months.

However, a Chinese friend living in Germany wrote to me during the severe drought period in southwesternern China, saying, "It is frequently stated that the forest coverage rate of China has continued to rise in recent years. Meanwhile, environmental problems are getting worse and worse." After checking relevant resources, I figured out that in China the standard for counting the forest coverage rate had been lowered. During the time when I was a college student, a "forest" was not a forest until its shade density reached 0.4, which means that a "forest" is a forest only when its projected area under the vertical sunshine covers an area of more than 40% of the ground. Nowadays in China, a forest requires a shade density of only 0.2. According to such a low standard, a few sporadic small trees can form a so-called forest. However, this so-called forest cannot reserve water and soil.

 


Walking alongside the mountain during the River Decade 


Mountains in Yunnan Province are mostly like this

Given the high rate of forest coverage in Southwestern China, there shouldn't be any drought, especially such a severe drought even though it had not rained for six months. In the Zhou dynasty, there was a record of no rain for seven years and the drought was more serious than this time.

Therefore, the lack of rainfall for six months is not the worst situation. However, it was not exactly true to say there had been no rain at all during the six months. In fact, some reports mentioned the term "effective rainfall", saying instead that there had not been any "effective rainfall" during the six months.

 


Artificial Forest
 


A “green desert” is believed to be under such a “forest”

In the past five years of the River Decade the focus has been on hydropower development. Of course, we will not criticize all hydropower stations. However, many new hydropower stations were constructed in southwestern China in recent years. Local hydropower stations, which are under construction and others that are planned, will not only dry the lower river but also lower groundwater levels. From the published statistics, in southwestern China, the total installed capacity of hydropower is anticipated to be as much as that of decades of the Three Gorges Dam. What impact will such large-scale hydropower development have on the environment? Is this also a reason for the drought?
Presently we have more than 80,000 reservoirs. When the severe drought occurred in the spring of 2010, some experts provided the following analysis: “according to the reports, it can be noted that the reservoirs had no water storage last year and they turned dry this year. The question is why the reservoirs had no water storage last year”.


 


 
The green on the precipice
 


The slogan says:Insist on the Outlook of Scientific Developme,Build Ecological Hydropower Station.

 

Looking at the several severe droughts in recent years, we have to ask the similar questionwhy couldn't our reservoirs store water? The experts then analyzed: “it can also be seen from relevant reports that every May the State Flood Control and Drought Relief Headquarters would ask all the reservoirs to draw off water in case the dams collapse during the flood period. More than one third of the dams in China are not safe. They are either too old or poorly constructed. As a result, when it is time to store water, our dams cannot function well. At the end of May or the beginning of June each year, water in the reservoirs must be released until it reaches the lowest water level. People are afraid that the flood would destroy the dam if too much water is stored in the reservoir. Nobody is willing to take the responsibility. The reservoirs wouldn't begin to store water until September. However, there is no rainfall after September.

That is definitely the major reason why most of the reservoirs in southwestern China were empty in spring this year. In addition, it indicates some problems in reservoir operation. The most serious problem is that many dams are poorly constructed so that they are not able to store water during the flood period. How dismal it is that so many dams are built but cannot function.

Unfortunately, the analysis and finger-pointing criticisms are not heard.

Drought, flood and rainstorms are threatening the livelihood of more and more people. Such ecological disasters are identified as part of Global WarmingGlobal Warming is irreversible.   


The future of our country
 


The future carried on the back


However, an investigation by an anthropologist Luo Kanglong attracted the interest of our journalists on Green Earth Journalist Salon. The investigation was done in a small Dong village named Huanggang in Guizhou Province. According to Luo, paddy fields in the village cover an area of 5,000 mu (1 mu equals 0.16 acre) with the deepest reserved water reaching a height of 0.5 meters. At the same time, the growth of the paddy will not be affected even with the water remaining in the field for 10 days. That is to say, one mu of paddy field can reserve 330 cubic meters of water during the rainstorm season. The 5,000 mu of the field actually equals the area of a small reservoir, capable of reserving 165,000 cubic meters of water. Meanwhile, the forests in Huanggan cover an area of 50,000 mu, most of which are secondary young and mature trees. Their flood reserving capacity can reach 110 cubic meters for each mu. Therefore, the overall volume of water reserved by the forests is about 5.5 million cubic meters. With the paddy field and the forests, a single Huanggan village can reduce 5,665 million cubic meters of water for downstream areas in rainstorm seasons without any cost increase. It may not seem a large number. However, if other Dong villages with similar characteristics are included, the overall flood division function is no less than a large and costly reservoir.
    Let’s put it in another way. Imagine it was half a century ago when some of the Yue nationality including the Dongs, Suis, Maonans, Mulaos, Chuangs, Puyis and Dais recovered their tradition of cultivating paddies, then the potential amount of reserved water for each mu of field during rainstorm seasons was 330 tons. With their 110 million mu of paddy field, the Yues can help to reserve water as large as that of the Three Gorges.       
According to Luo Kanglong, a nationality’s traditional way of living is very similar wherever its people live. For the traditional life of a Dong farmer, storable water resources are certainly limited-usually less than 5,000 tons. The point is, however, if traditional ways of living for all Dongs were maintained, then the real storage capacity actually equals that of a huge reservoir.
As an anthropologist, Luo Taikong mentioned that the water resources required for livelihood and biodiversity maintenance in Huanggang, a village of the Dong nationality, might not achieve economic profits according to modern statistical criteria. However, it contributes to the stability of a community, a settlement, and the carriers of biodiversity and cultural diversity. These are the aspects that were not considered, or were ignored, in our construction of reservoirs and water conservation structures.
  
 


 
It was widely agreed by experts in our on-bus class that we should clearly note the following facts: nowadays droughts and floods are more frequent and their damage greater, while central-government investment in water conservation projects, which is much higher than in education, is also increasing. Why has the greater investment resulted in worse results? Maybe we should reconsider the water conservation policies.
As pointed out by Hou Mingming, nonrenewable resources should be protected, while renewable ones should be developed and utilized. We should change the development model from a resources-relaying one to a policy-pushed one. He suggested that the central government should offer special open policies to Yunnan Province. For example, Yunnan can be turned into a low-tariff area. With a mere five percent lower tariff, larger flows of goods, people and money can then travel in and out of Southeast Asia and South Asia through  Yunnan Province. Therefore, the development period of Yunnan could be prolonged for another 50 years; sustainable social and economic development will be possible at the lowest cost of natural resources consumption. The issue of ecological environmental protection and development in Yunnan is related not only to ecology, but also to the local economy, society and politics. We should reduce pressure on the province to enable its ecology to recover, to increase its productivity from nature, and to maintain its biodiversity.


 

 
Diesel oil shortage in Yunnan
 

 
Sunset over the river
 


Our bus on the mountain road


Here is another point widely agreed during our on-bus discussion: dealing with emergencies is definitely our first priority when faced with droughts, however have we ever taken a long-term perspective on whether ecologically fragile and culturally diverse areas such as western China should be developed as they are now?
We will spend ten years on this land, walking, interviewing, recording and making changes.
 Tomorrow we will arrive at Lijiang, not only to see its snow-capped mountains and to embrace the Naxi culture, but also to visit a local power station in Liyuan. It happens to be undergoing environmental assessment. Some people told me that the main river there had been cut-off. Is that true? The river  undergoing environmental assessment has already been cut-off?


Translator: Yang Wenlong, Li Hongyi
Proofreader: Karen




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