Erhai Lake, covering 252 square km, is the mother lake of the Dali people. However, in the 1980s, the lake became so polluted that it emitted a putrid smell. Then, it saw three major blue-green algae outbreaks—in 1996, 2003 and 2013.
In recent years, its water quality has greatly improved thanks to the local government’s green efforts such as shutting down mines around the lake and banning the use of fertilizers that contain nitrogen and phosphorus.
Continuous efforts
However, in spite of the improvement, a lot more needs to be done for the lake’s water quality to reach Grade I, the best in China’s five-tier quality system for surface water.
As fertilizer use is a major source of pollution, in 2021, Zhang Fusuo, a member of the Chinese Academy of Engineering and head of the National Academy of Agriculture Green Development at China Agricultural University (CAU), who specializes in plant nutrition, was invited by the local government to Dali to help find a greener way to cultivate crops.
In February 2022, CAU, Yunnan Agricultural University and the Dali Bai Autonomous Prefectural Government jointly established the Gusheng Village Science and Technology Backyard (STB) in Gusheng Village in Dali, to explore a new path combining Erhai preservation with high-quality agricultural development. The STB is a program that brings researchers to the rural areas to carry out studies on sustainable agriculture and provide free onsite guidance. In 2009, CAU collaborated with Quzhou County in Hebei Province to set up the first STB in Baizhai Village in Quzhou. Today, China has more than 1,000 STBs and the model has been promoted to Laos and African countries by the Food and Agriculture Organization of the United Nations.
Gusheng Village sits between Cangshan Mountain and Erhai Lake. The Yangxi, one of the 18 rivers that originate from Cangshan Mountain and empty into Erhai Lake, flows through the village.
In 2015, President Xi Jinping visited the village to learn about conservation efforts at Erhai Lake. After posing for a photo with local officials, he said, “I’m going to hold onto this picture, and I hope that when I come back in a few years I will see that the water has become cleaner.”
To make the water cleaner, under the STB program, Zhang has invited more than 300 researchers from 30-plus research institutes and universities to the village to work out a solution. The number of STBs in the village has increased to 11, all focusing on different fields.
Zhang and his colleagues set the goal of reducing the nitrogen and phosphorus runoff from the village’s farmland into the lake by 30 to 50 percent and increasing the output value per hectare of farmland to 150,000 yuan ($21,146). The village serves as a pilot zone and the experiences gained there will be applied to other villages in the future.
To identify the sources of pollution, researchers have collected more than 3,000 water samples since last April, monitoring the water quality across a 4.8-square-km area from the source of the Yangxi River in Cangshan Mountain, to the village and then to Erhai Lake.
Through their analysis of the water samples, the team found the village’s sewage water contributed 39 percent of the pollution and the farmland contributed 35 to 55 percent.
In addition to identifying polluting sources, Zhang’s team had to help the village find ways of growing crops which are both environmentally friendly and economically rewarding.
The team has introduced to villagers an eco-friendly fertilizer for rice and biodegradable mulch to cover the soil to retain moisture and nutrients. Application of these technologies has increased rice output by 30 percent, reduced the runoff of nitrogen and phosphorus by 30 percent and slashed fertilizer costs by 50 percent. The new fertilizer has been applied to more than 1,000 hectares of land in the prefecture this year.
Green experiences
These researchers’ efforts to achieve a balance between cleaning up Erhai Lake and increasing farmers’ incomes echo the theme of this year’s Erhai Forum on Global Ecological Civilization Construction: Man and Nature in Harmony Toward a Path to Modernization.
The forum, held in Dali on May 28, was jointly hosted by China International Communications Group (CICG), the Yunnan Provincial Government and China Public Relations Association. It has taken place annually since 2021. More than 400 experts, scholars, government officials and corporate executives participated in the forum this year.
At the event, Zhang shared the team’s experiences. He said he hopes the experiments he and his colleagues have carried out in Gusheng Village will provide an example of high-quality and green agricultural development for the whole country and contribute to global sustainable development.
Zhang later told Beijing Review that environmental protection and economic development can be achieved simultaneously and scientific and technological progress has made it possible to strike a balance between both.
At the forum, Du Zhanyuan, President of CICG, emphasized that ecology is crucial to human survival and development. He pointed out that Chinese modernization is the modernization featuring harmony between humanity and nature.
Du called for genuine multilateralism, expressing his hope that nations could exchange experiences and technologies related to climate change, energy conservation and emission reduction, to foster a global ecological and environmental governance system characterized by fairness, rationality and mutually beneficial cooperation.
Hans Lambers, a fellow with the Royal Netherlands Academy of Arts and Sciences and the Australian Academy of Science, told Beijing Review that short-term benefits are too often pursued despite greater long-term losses, when asked about the difficulties in balancing economic development and environmental protection. “Preventing pollution, such as what happened to Erhai Lake, is much cheaper than repairing the damage. A long-term vision is required, rather than a focus on short-term benefits,” he said.
The forum featured five parallel forums which focused on themes such as building the ecological economy, the role of ecology in the Chinese path to modernization and enterprises’ contributions to low-carbon development.
Throughout the day, companies shared their successful green practices.
Pan Hao, Deputy General Manager of the Carbon Asset Management Co. under the State Power Investment Corp. Ltd. (SPIC), one of the five major power generation groups in China, shared his company’s experiences in achieving both environmental protection and economic benefits in Qinghai Province.
Xiahelesi Village in Gonghe County in Qinghai used to rely on livestock farming. However, in the 1980s and 1990s, the vast grassland surrounding the village became desertified due to drought, wind erosion and overgrazing.
Since 2000, the government has taken a series of measures, including a ban on grazing, to manage desertification. However, the government funds offered to graziers in compensation for the ban were insufficient to maintain their living standard.
Large desert areas and ample sunshine are the ideal conditions for developing the photovoltaic (PV) industry and in 2012, SPIC built a PV power generation base in the village to help the county develop a PV industry.
The solar panels have reduced wind speeds in the area by nearly 50 percent and as they shade the ground from sunshine, evaporation, too, has reduced, in turn increasing the soil’s ability to retain water. This all benefits the recovery and growth of the grasses that once covered the area. Grasses have once again begun to grow on the barren land, with some standing as tall as 1 meter. The water used to wash the solar panels every month also promotes the growth of the grass.
Because the grasses may grow taller than the solar panels, blocking them from the sunshine and creating a fire risk in winter, the PV company now allows villagers to graze their sheep on its land.
In the beginning, more than 600 sheep owned by 16 farmers were allowed to graze under the panels. And the more power generation companies settled at the base, the more opportunities arose for farmers to graze their sheep. Pan said today’s number of sheep grazing under solar panels in the region exceeds 20,000. The companies have also hired local villagers to wash the panels and work as security guards, creating jobs and increasing incomes.
The symbiosis has become so successful that the company has now raised the height of the panels specifically to make it easier for sheep to graze. In addition to reducing coal use and therefore carbon and sulfur emissions, the PV industry has also restored grasslands to Xiahelesi and helped increase local farmer incomes. This model provides an example of how economic growth and environmental protection can go hand in hand. –The Daily Mail-Beijing Review news exchange item
