Combined effects of Ocean acidification and ocean warming on the biochemical composition and breeding of economic fish from the East Sea of China Applicant: Zheng Yangqiao Tel: Institution: East China Sea Fisheries Research Institute

Reasons to choose the project ： 1 、 > (3) carry out the study of the effects of global climate changes on the fisheries and ecology, analyze the impact of global warming and ocean acidification on the distribution and habit of fishes. 2 、 > （ ） “The study of the impact of global climate changes on the open sea fisheries” 。

Background ： According to the report of WMO ， the concentration of CO 2 has increased by 36% since industrial revolution began in 18 century, and will increase at a rate of 0.5% each year. The anticipated concentration of CO 2 will reach ppmv at the end of this century.

1 、 ocean acidification ： The pH of seawater has decreased 0.1 unit because of the increasing CO 2 concentration, and will reduce 0.3 － 0.4 units by 2100 (the concentration of hydrogen ion in seawater increase by %, equivalently)

If current trends of ocean acidification continue, the marine ecosystems would be devastatingly destroyed. It will also causes acid blood, leading to lower immune response, metabolic disorders and asphyxia, while the hatching rate and larval fish may be particularly sensitive to acidification. On the other hand, it also will change the composition of primary production and food chain structure. 食物链？？

2 、 Ocean warming ： In the past 40 years, the averaged ocean temperature had increased by 1.13 o C, in the next 100 years, it will elevate o C 。 Water temperature is an important factor in affecting the growth of fish. Scholars in many countries of the world are studying on the relationship between the ocean warming and fishing industry. The changes in ocean circulation caused by ocean warming, will affect growth, breeding, migration routes and even sex ratio of many species.

Research Content ： 1. The coupling effect ocean warming and ocean acidification on the ocean species composition of photosynthetic organisms (the ratio of addicted to carbon species and nitrogen species) 2. The coupling effect seawater warming and ocean acidification on the growth and biochemical composition of some economy fish. 3. The coupling effect seawater warming and ocean acidification on the reproduction capacity of economy fish.

Research objectives: 1 、 The composition changes of addicted carbon and addicted nitrogen species. The ocean warming and ocean acidification have changed ocean carbonate system, created changes ratio of carbon and nitrogen in seawater, and thereby affected the composition and proportion of photosynthetic organisms. 2 、 The coupling effects on growth and biochemical composition of fish. The growth and biochemical composition of fish may exhibit different responses to ocean warming and ocean acidification caused by food and changes in marine environment. 3 、 The coupling effects of ocean warming and ocean acidification on the reproduction of fish. Ocean warming and ocean acidification will not only have an impact on breeding cycle of fish, but also on the hatching rate of fertilized eggs.

Key issues to be solved ： First, Make clear the combined effects of water warming and ocean acidification on the biochemical composition of economy of the fish from East China Sea. Most previous studies focus on a single environmental factors impact on fish and most of them concentrated in the temperature, whereas the impact of ocean acidification on fish is less reported. Second, Reveal the response of hatching rate of fish to ocean acidification and ocean warming From the molecular level (DNA damage).

Gao K. & Zheng Y. Combined effects of ocean acidification and solar UV radiation on photosynthesis, growth, pigmentation and calcification of the coralline alga Corallina sessilis (Rhodophyta). Global Change Biology, 2010, 16: (SCI) Research groundwork: In recent years, the applicant has engaged in the research on the marine ecosystem. The applicant has been well trained to use the specific research techniques and analysis methods. Our laboratory has accumulated a wealth of hydrology, water chemistry, aquatic biology and fisheries resources survey, published numerous research papers and monographs. Such documents can provide reference for the project. The East China Sea Fisheries Research Institute can fully meet the needs of scentific research with some key laboratory.