Language
Country/Area
No result found
iscover how Ulva prolifera affects marine ecosystems and causes environmental crises
Ulva prolifera, formerly known as Enteromorpha prolifera, commonly known as branched lettuce, is a species of seaweed with a global distribution. This marine algae has not only become part of the aquatic ecosystem, but has also caused major environmental problems in some areas. The species is characterized by its filamentous and interwoven appearance, in fact they have a tubular structure that can reach several meters in length and no more than 5 mm in diameter. These seaweeds that float on the sea surface or wash up on the beach range in color from light green to grass green, but their impact on the marine ecosystem cannot be underestimated.
Distribution and Growth
In Europe, Ulva prolifera can be found in Bulgaria, France, Great Britain, Greece, Ireland, Portugal, Romania, Slovenia, Spain, and the Danish island of Rallan. It is also quite common in the Canary Islands and Madeira in Africa, and in Alaska, California, Florida, Texas, and Washington in the United States. The algae also appears in Central American countries such as Costa Rica, El Salvador, Panama and Cuba. While most is wild seaweed, some is grown in aquaculture in countries such as Japan, South Korea and China.
The formation of green tide
Since 2007, China's Yellow Sea has seen a green tide every summer due to an overgrowth of Ulva prolifera. This green tide has become a major environmental concern, involving the influence of multiple factors, including natural, human, physical and chemical factors and warming of local waters. The dynamics of these factors explain the sudden proliferation of Ulva prolifera on the east coast of China in 2007. The 2008 Beijing Olympic Games was held in Qingdao, and the green tide at that time attracted widespread attention because of its profound impact on the economy and ecology.
Every spring, since 2007, Ulva prolifera first appears as small-scale floating algae along the coast of Jiangsu, and then migrates northward and accumulates driven by monsoons and ocean currents.
As these algae drift along the coast of the Yellow Sea, they eventually accumulate in the coastal waters of the Shandong Peninsula in June and July, and gradually decrease over time. Through the analysis of meteorological and environmental data, the study found that the waters along the coast of Jiangsu are the source of Ulva prolifera reproduction. This situation is closely related to the development of laver farming. When excess nutrients enter the water, they provide a suitable environment for the growth of algae and the formation of green tides.
Environmental hazards
The overgrowth of Ulva prolifera has caused serious harm to the marine ecosystem. Algae cover on the sea surface blocks sunlight from reaching the underwater area, creating a shallow, lightless zone. The disappearance of sunlight poses a deadly threat to underwater organisms that need photosynthesis, including plants and microorganisms. With insufficient light, the photosynthesis of phytoplankton is severely affected, which has a devastating impact on the local food chain.
As algae biomass increases, their respiration intensifies, reducing oxygen levels in local waters, posing a threat to all life.
In addition, when this algae washes ashore, it releases a pungent odor as it degrades, harming the environment and local tourism value. Excessive accumulation of Ulva prolifera not only harms the environment, but also affects the local underwater ecosystem.
Countermeasures
Traditionally, the way to combat coastal algae blooms is to collect them directly and dispose of them properly, or to set up nets near the coast to stop the green tide from invading. However, current research is looking at using microbial complex sprays to promote rapid degradation of algae, seeking more effective long-term solutions.
Conclusion
In the face of the widespread presence of Ulva prolifera and its impact on marine ecosystems, how should humans balance production needs and environmental protection?
