龙须菜在网箱养殖区的生物修复研究

在福建省东山县八尺门网箱养殖区的浅水区吊养面积约0.7 hm2的龙须菜(Gracilaria lemaneiformis),研究龙须菜对网箱养殖区水质的修复效果。通过对实验区及其内外两侧的定点监测,以及对与潮流方向一致和垂直的2个断面的监测,结果表明,修复区的溶解氧(DO)浓度明显高于非修复区,无机氮(IN)、无机磷(IP)浓度低于非修复区,由此可见,通过海水交换,龙须菜可以吸收流经修复区的IN、IP,并提高流出修复区的海水的DO水平。这有利于改善网箱养殖区的海水水质,提高网箱养鱼的成活率和生长率,促进海水养殖的可持续发展。中国水产科学,2007,14(3):488-492]

Bioremediation in fish cage-farming areas by Gracilaria lemaneiformis

Eutrophication caused by caged fish culture has become the most important environmental problem in mariculture area of Chinese coastal waters.Since excess nutrients can be uptaken by macroalga and ultimately removed from water by alga harvest,and DO concentration is enhanced as well,macroalga-based bioremediation of eutrophication is possible to be the best way to solve such environmental problem.In this study,Gracilaria lemaneiformis introduced from Shandong Province was employed as bioremediator to rescue the eutrophication of the fish cage-farming area,Bachimen,Dongshan Conuty,Fujian Province.The experiments with bioremediation area about 0.7 hm2 were conducted from January to March in 2003.Water quality was monitored at three fixed sites,including bioremediation and non-bioremediation areas,and two transects parallel or perpendicular to the tide direction during the experimental courses.The results showed that the specific growth rate of G.lemaneiformis was 4.2% during the experiment.The IN(inorganic nitrogen) and IP(inorganic phosphorus) concentrations in bioremediation area were lower than those in non-bioremediation areas.The DO concentration in bioremediation area was significantly higher than that in non-bioremediation area.In particular,the DO concentration of downstream seawater increased and as IN and IP were taken up by seawater exchange.It is possible to alleviate the pollution of marine environment,prevent eutrophication and improve fish survival rate and growth rate.Thus,this study demonstrated a promising ecological approach of sustainable mariculture.