Clipping Board » Environmental Pollution & Change ─ How dirty the human heart is, how dirty the environment will be...
Update Date: 2008/12/07 09:36 [China Times, Special Report by Xu Junwei]
Humans are both fearful and filled with fantasies and expectations towards the vast and boundless ocean. However, despite believing we are very familiar with the ocean, we continuously extract marine resources based on our limited knowledge, using methods we deem correct to conserve and utilize this great granary. As scientists uncover more and more new knowledge about the ocean, humans should not only adjust the ways we utilize marine resources but also ponder how to face the mysterious ocean.
Fang Lixing, former director of the National Museum of Marine Biology and Aquarium and current chair professor at Cheng Shiu University, during the "Encountering Science" lecture co-hosted by the China Times and National Central University, pointed out based on over 30 of the world's latest marine research conclusions collected over the years, how ignorant humans are about the ocean under global changes. Whether marine resources are another opportunity for humanity or another ecological disaster, we should deeply reflect on this with new knowledge.
Fang Lixing said that the ocean has always been regarded as a great granary for humanity, and we have continuously used various methods we believe to be correct to extract marine resources. However, as early as 2003, a paper in the journal "Nature" showed that less than 10% of large economic fish species remain; in 2006, the journal "Science" also stated that economic aquatic species such as tuna, flatfish, and lobster would disappear by the mid-21st century.
According to statistics from the United Nations Food and Agriculture Organization, the total global aquatic biomass in 2006 was 160 million tons, with 41% coming from aquaculture. Since 1990, the output of aquaculture has been growing at a rate of 8% to 9% annually.
In fact, 20% to 50% of the feed used in aquaculture is fishmeal, which comes from small fish at the bottom of the marine nutrient cycle ecological chain, largely accumulated in the coastal continental shelf areas that make up a small proportion of the ocean. These continental shelf areas are also the most severely affected by eutrophication, sediment aging, disease pathogens, and land-based pollution. Fang Lixing reminded that humans should develop marine aquaculture more cautiously.
If the development of coastal aquaculture is limited, do not think that deep-sea resources will be a new hope for humanity. Fang Lixing said that 99% of the ocean's productivity comes from the surface layer, and 95% of the ocean is deep sea over 200 meters, where the number of marine organisms is actually not large. Moreover, as humans have fished away the food (fish) from the upper layers of the ocean, the biomass in the lower layers will also decrease.
What about the much-touted marine biotechnology? Fang Lixing pointed out that 80% of deep-sea species are very basic microorganisms, which are more prone to genetic exchange. However, the genetic transfer of terrestrial species is currently restricted due to controversy. If humans develop marine biological genetic transfer, the new genetically modified species in the ocean, without the barriers of mountains and rivers, could potentially cause even greater repercussions.
Even setting aside the marine resources that humans are concerned about, he said, a research paper in "Nature" last year pointed out that the ability of marine plankton to absorb carbon dioxide is actually greater than we understood.
The paper pointed out that more than half of the carbon dioxide released since the Industrial Revolution has been absorbed by the ocean and stored at the bottom of the sea after the death of plankton. If disturbances in the deep sea cause this carbon dioxide to be released, the problem of global warming would become even more severe. This is something humans had not considered before.
Fang Lixing believes that the continuous emergence of new knowledge about the ocean reflects how vast human ignorance of the ocean is. As we develop or claim to conserve the ocean, we should seriously reconsider: Are the methods we are using correct?
Source: http:/ / tw. news. yahoo. com/ art……url/ d/ a/ 081207/ 57/ 1aqp2. html
Lobster and Tuna to Vanish by Mid-21st Century
Humans are both fearful and filled with fantasies and expectations towards the vast and boundless ocean. However, despite believing we are very familiar with the ocean, we continuously extract marine resources based on our limited knowledge, using methods we deem correct to conserve and utilize this great granary. As scientists uncover more and more new knowledge about the ocean, humans should not only adjust the ways we utilize marine resources but also ponder how to face the mysterious ocean.
Fang Lixing, former director of the National Museum of Marine Biology and Aquarium and current chair professor at Cheng Shiu University, during the "Encountering Science" lecture co-hosted by the China Times and National Central University, pointed out based on over 30 of the world's latest marine research conclusions collected over the years, how ignorant humans are about the ocean under global changes. Whether marine resources are another opportunity for humanity or another ecological disaster, we should deeply reflect on this with new knowledge.
Fang Lixing said that the ocean has always been regarded as a great granary for humanity, and we have continuously used various methods we believe to be correct to extract marine resources. However, as early as 2003, a paper in the journal "Nature" showed that less than 10% of large economic fish species remain; in 2006, the journal "Science" also stated that economic aquatic species such as tuna, flatfish, and lobster would disappear by the mid-21st century.
According to statistics from the United Nations Food and Agriculture Organization, the total global aquatic biomass in 2006 was 160 million tons, with 41% coming from aquaculture. Since 1990, the output of aquaculture has been growing at a rate of 8% to 9% annually.
In fact, 20% to 50% of the feed used in aquaculture is fishmeal, which comes from small fish at the bottom of the marine nutrient cycle ecological chain, largely accumulated in the coastal continental shelf areas that make up a small proportion of the ocean. These continental shelf areas are also the most severely affected by eutrophication, sediment aging, disease pathogens, and land-based pollution. Fang Lixing reminded that humans should develop marine aquaculture more cautiously.
If the development of coastal aquaculture is limited, do not think that deep-sea resources will be a new hope for humanity. Fang Lixing said that 99% of the ocean's productivity comes from the surface layer, and 95% of the ocean is deep sea over 200 meters, where the number of marine organisms is actually not large. Moreover, as humans have fished away the food (fish) from the upper layers of the ocean, the biomass in the lower layers will also decrease.
What about the much-touted marine biotechnology? Fang Lixing pointed out that 80% of deep-sea species are very basic microorganisms, which are more prone to genetic exchange. However, the genetic transfer of terrestrial species is currently restricted due to controversy. If humans develop marine biological genetic transfer, the new genetically modified species in the ocean, without the barriers of mountains and rivers, could potentially cause even greater repercussions.
Even setting aside the marine resources that humans are concerned about, he said, a research paper in "Nature" last year pointed out that the ability of marine plankton to absorb carbon dioxide is actually greater than we understood.
The paper pointed out that more than half of the carbon dioxide released since the Industrial Revolution has been absorbed by the ocean and stored at the bottom of the sea after the death of plankton. If disturbances in the deep sea cause this carbon dioxide to be released, the problem of global warming would become even more severe. This is something humans had not considered before.
Fang Lixing believes that the continuous emergence of new knowledge about the ocean reflects how vast human ignorance of the ocean is. As we develop or claim to conserve the ocean, we should seriously reconsider: Are the methods we are using correct?
Source: http:/ / tw. news. yahoo. com/ art……url/ d/ a/ 081207/ 57/ 1aqp2. html