Most of the 26 reservoirs on Taiwan’s outlying islands are affected by eutrophication, while five out of the 20 category-one reservoirs on Taiwan proper are also affected by eutrophication, an Environmental Protection Administration (EPA) report showed.
Eutrophication is caused by an excess of nutrients, which results in a buildup of plant life that prevents light and oxygen from entering the water.
In April, the Mingde (明德), Baihe (白河), Jingmian (鏡面), Chengcing Lake (澄清湖) and Fengshan (鳳山) reservoirs were the five category-one reservoirs with the most eutrophication, the report said.
Photo: Wu Chun-feng, Taipei Times
The Fengshan reservoir scored 70 on Carlson’s trophic state index, the highest out of the five, the EPA said, adding that there are 14 mesotrophic reservoirs.
The Feitsui Reservoir (翡翠水庫), which provides water for the Taipei metropolitan area, has the best water quality, and is also considered oligotrophic, the report said.
Of the six category-two reservoirs, the Sishi (西勢), Dapu (大埔) and Agongdian (阿公店) reservoirs are considered eutrophic, while the remaining three are mesotrophic, it said.
As for reservoirs on outlying islands, only the Sian (西安) reservoir in Penghu County is mesotrophic, while the other 25 are eutrophic, it said.
Mesotrophic water contains a moderate amount of nutrients, encouraging the growth of submerged aquatic plants, while oligotrophic water is clear and of higher quality.
Speaking about the report on Friday, Hou Chia-hung (侯嘉洪), a professor at National Taiwan University’s (NTU) Graduate Institute of Environmental Engineering, said that precipitation levels can affect the water quality of reservoirs.
Decreasing water levels can cause a higher-than-normal concentration of nitrogen and phosphorus in the water, resulting in an algae bloom, he said.
It is suspected that toxins from algae can negatively affect human health, and as 70 percent of water for civilian use originates from reservoirs, eutrophication is placing an increased burden on water filtration systems, he said.
As eutrophication decreases the amount of oxygen in the water, it further unbalances the ecology, Hou added.
EPA Department of Environmental Monitoring and Information Management Director-General Chang Shuenn-chin (張順欽) said that the eutrophication of reservoirs on islands was caused by their small size and lack of water inflows to prevent stagnation.
A lack of rainfall, as well as bird feces, also contribute to the eutrophication of reservoirs, he added.
The eutrophication of the Fengshan Reservoir was caused by its water being diverted to other places, and due to the natural water quality of the Gaoping (高屏) and Donggang (東港) rivers, Chang said, adding that a lack of rainfall last year was also a factor.
Hou said that changing how the land around the reservoirs is used is key to stabilizing reservoir water supply.
“We still have a long way to go in terms of environmental conservation and decreasing sources of pollutants,” he said.
‘DENIAL DEFENSE’: The US would increase its military presence with uncrewed ships, and submarines, while boosting defense in the Indo-Pacific, a Pete Hegseth memo said The US is reorienting its military strategy to focus primarily on deterring a potential Chinese invasion of Taiwan, a memo signed by US Secretary of Defense Pete Hegseth showed. The memo also called on Taiwan to increase its defense spending. The document, known as the “Interim National Defense Strategic Guidance,” was distributed this month and detailed the national defense plans of US President Donald Trump’s administration, an article in the Washington Post said on Saturday. It outlines how the US can prepare for a potential war with China and defend itself from threats in the “near abroad,” including Greenland and the Panama
The Chinese Nationalist Party (KMT) is maintaining close ties with Beijing, the Democratic Progressive Party (DPP) said yesterday, hours after a new round of Chinese military drills in the Taiwan Strait began. Political parties in a democracy have a responsibility to be loyal to the nation and defend its sovereignty, DPP spokesman Justin Wu (吳崢) told a news conference in Taipei. His comments came hours after Beijing announced via Chinese state media that the Chinese People’s Liberation Army’s Eastern Theater Command was holding large-scale drills simulating a multi-pronged attack on Taiwan. Contrary to the KMT’s claims that it is staunchly anti-communist, KMT Deputy
RESPONSE: The government would investigate incidents of Taiwanese entertainers in China promoting CCP propaganda online in contravention of the law, the source said Taiwanese entertainers living in China who are found to have contravened cross-strait regulations or collaborated with the Chinese Communist Party (CCP) could be subject to fines, a source said on Sunday. Several Taiwanese entertainers have posted on the social media platform Sina Weibo saying that Taiwan “must be returned” to China, and sharing news articles from Chinese state media. In response, the Mainland Affairs Council (MAC) has asked the Ministry of Culture to investigate whether the entertainers had contravened any laws, and asked for them to be questioned upon their return to Taiwan, an official familiar with the matter said. To curb repeated
Myanmar has turned down an offer of assistance from Taiwanese search-and-rescue teams after a magnitude 7.7 earthquake struck the nation on Friday last week, saying other international aid is sufficient, the National Fire Agency said yesterday. More than 1,700 have been killed and 3,400 injured in the quake that struck near the central Myanmar city of Mandalay early on Friday afternoon, followed minutes later by a magnitude 6.7 aftershock. Worldwide, 13 international search-and-rescue teams have been deployed, with another 13 teams mobilizing, the agency said. Taiwan’s search-and-rescue teams were on standby, but have since been told to stand down, as