Effects of Soil Salinity on the Quality of Carrot

采用土壤盆栽试验,设置6个盐度水平(0、500、1000、1500、2000、2500 Mg/kg),研究胡萝卜种植过程中盐度对其叶绿素、维生素C、可溶性糖、可溶性蛋白质及硝酸盐含量的影响。结果表明,种植胡萝卜的土壤盐度控制在500 Mg/kg,可以提高胡萝卜的品质,减少盐分对土壤的损伤。具体表现为,500 Mg/kg盐度处理对胡萝卜叶绿素含量无显著影响,而高盐度使胡萝卜叶绿素总含量降低;500~1000 Mg/kg盐度可增加胡萝卜维生素C和可溶性蛋白质含量;可溶性总糖含量以500 Mg/kg处理的降低幅度最小,500~2000 Mg/kg处理使胡萝卜硝酸盐含量呈降低趋势,但高盐度(2500 Mg/kg)则会增加其硝酸盐含量。A soil pot experiment with different levels of saltnity(0,500,1500,2000,2500 mg/kg) were carried out to study the effects of salinity on the quality of carrot.The results showed that controlling certain salinity 500 mg/kg,could improve the quality of carrot.Because the salinity of 500 mg/kg had no effect on the chlorophyll content of carrot,and high salinity caused total chlorophyll content decreased,low salinity was conducive to the promotion of carrot synthesis of vitamin C and soluble protein,soluble sugar content of carrot was decreased by the increasing of salinity levels,Nitrate content in carrots increased at the high salinity(2500 mg/kg) treatment.厦门市科学技术局项目(3502Z20071098

A study on bioremediation of eutrophication of mariculture waters by Gracilaria lemaneaformis

于2002年至2004年期间,在福建省东山岛的八尺门鱼类网箱养殖区、西埔湾对虾养殖区、乌礁湾鲍鱼养殖区等进行了龙须菜(G racilaria lem aneaf orm is)对动物海水养殖造成的富营养化的生物修复研究。结果表明,从围隔实验到小面积的海区实验到大面积的海区推广试点,龙须菜对富营养化的海水均有良好的修复效果。围隔实验中,龙须菜能使网箱养殖区缺氧的海水达到过饱和状态,对无机氮(IN)、无机磷(IP)的去除率达80%以上;实验海区,修复区的溶解氧(DO)浓度明显高于非修复区,IN、IP、叶绿素(Ch l-a)浓度低于非修复区;推广海区,鲍鱼养殖污水流经龙须菜养殖区后,IN、IP得到有效的吸收,DO浓度得到提高。因此,大面积养殖龙须菜对减轻养殖污水对海区的污染,防止水体富营养化,抑制赤潮的发生有积极作用。Eutrophication caused by mariculture has become a serious environmental problem in Chinese coastal waters.Since macroalgae can absorb nutrients and increase the concentration of dissolved oxygen(DO),and can be ultimately removed from water by being harvested,macroalga-based bioremediation of eutrophication would be the best way to solve such environmental problems.The effects of Gracilaria lemaneaformis remediated eutrophication were studied.G.lemaneaformis,red seaweed,originated in Shandong Province,was cultivated on ropes in three typical mariculture areas at Dongshan island,Fujian province where mariculture is advanced.The mesocosm experiment was conducted in Bachimen fish-cage area;the bioremediation experiment——in a field about 3 hm~2 in Xipu bay where the shrimp-farm and urban sewage is discharged;and in the spread application experiment,about 400 hm~2 were tested in Wujiao bay where abalone sewage is discharged.Water quality parameters were monitored during all the experimental stages.According to different tide and depth of the sea,two floating-rafts,i.e.bamboo raft and string raft,were devised to cultivate G.lemaneaformis on ropes in sea.The results demonstrated that the effects of bioremediation of eutrophication of mariculture waters by G.lemaneaformis were obvious regardless to the place of experiment: in mesocosm one,in a small-scale's bioremediation or in large area's spread application.The results of mesocosm experiments showed that G.lemaneaformis increased DO from low concentration to supersaturation and increased DO saturation from about 60% to 200%;in meantime,it absorbed the inorganic nitrogen(IN) and inorganic phosphorus(IP) above 80% during 3～4 days.In bioremediation area in Xipu bay,the specific growth rate of G.lemaneaformis was 9% during the first month and 6% during the next half month.The DO concentration in bioremediation area was significantly higher than that in non-bioremediation area: the highest DO concentration in bioremediation area was 5.6 mg·L~(-1) higher than that in non-bioremediation area in the same monitoring transect,the highest DO saturation was 198.7%.Furthermore,it increased the DO concentration of downstream seawater.And the IN and IP concentrations in bioremediation area were lower than those in non-bioremediation area.Besides,the microaglae were restrained,the concentration of Chlorophyll-a in bioremediation area was lower than that in non-bioremediation area,whereas,the transparence was contrary.In spread application area,when the abalone cultural sewage went through G.lemaneaformis cultural areas,the nitrogen and phosphorus were effectively absorbed.Especially,the IP concentration of abalone cultural sewage discharging area was above 0.05mg·L~(-1),however,that in G.lemaneaformis cultural areas was below 0.015mg·L~(-1).The DO concentration was increased in G.lemaneaformis cultural areas,its saturation was above 120%,the highest one was 166%,but,in non-cultural areas,the DO saturation was about 100% normally.In conclusion,by large farming of G.lemaneaformis in animal maricultural areas,it is possible to alleviate the pollution of marine environment,prevent from eutrophication and control the red tide.At the same time,because G.lemaneaformis was the ideal food for abalone and material to produce agar,it could resolve the problems of the local abalone culture.Hence,large farming of G.lemaneaformis in the eutrophic mariculture areas could reduce environmental impact and increase economic output,and good environmental and economic advantages would be obtained.福建省重大科技资助项目(2002Y005)~

A Preliminary Study on Prediction of Dissolved Oxygen Lack After Near Shore Red Tide Occurrence and Biological Prevention of Red Tide

福建省东山县八尺门网箱养殖区发生中肋骨条藻赤潮期间,跟踪监测赤潮消亡过程及消亡后DO的变化,同时采用室内模拟的方法观测.研究江蓠对赤潮消亡后水体DO的影响.结果表明:江蓠可以减缓赤潮消亡后出现的水体缺氧;采用室内模拟的方法可以预测海区赤潮消亡后DO的变化趋势.Investigation of the dissolved oxygen lack after near shore red tide occurence was carried out during period of a Skeletonema costatum red tide occurred in Bachimen caged marine culture area of Dongshan County of Fujian Province.The concentration of dissolved oxygen (DO) during and after the red tide occurrence was monitored for both on scene and indoor mimic water systems.Gracilaria,a kind of large algae,was applied to the red tide water to investigate its influence on DO.The results showed that the algae could decrease the effect of DO lack after red tide happened.The indoor mimic method might be adopted to predict the concentration trends of DO on scene after red tide occurred.福建省自然科学基金重大项目(2002Y005)资

Bioremediation of Gracilaria lichenoides in fish cage-farming areas

2003年8～12月,利用菊花心江蓠(Gracilarialichenoides)在福建省东山县八尺门网箱养殖区进行生物修复实验。通过定点跟踪监测,定点连续监测,断面监测和平面监测,结果表明,江蓠对受污染的海水具有较好的修复效果。菊花心江蓠能有效提高水中的DO浓度,使修复实验区的DO浓度明显高于非养殖区和网箱养殖区的DO浓度;菊花心江蓠还能降低水中的IN、IP浓度,特别是3种价态的IN中,菊花心江蓠优先吸收铵氮,这对减轻网箱养殖区自身污染的影响更具实际意义。Water self-pollution and eutrophication have becoming the most important environmental problem in mariculture as its fast development.Using macroalgae to remove nutrition elements such as N and P,and produce O_2 is one of the most effective ways to prevent the pollution, enhance dissolved oxygen concentration, and avoid eutrophication.Bioremediation of polluted mariculture water has become the focusing point for the researchers all over the world.Gracilariae is a group of macroalgae, can improved the water quality and can be used as the raw material for agar production and the feed for abalone.Dongshan County of Fujian Province is an important base of abalone culture and cage culture in the nation.After about twenty years of mariculture, some sea areas such as Bachimen fish cage-farming in Dongshan County have been seriously polluted.The technique utilizing Gracilaria to remediate the mariculture water environment has been studied.Gracilaria lichenoides,which was introduced from Taiwan province in 1998,was applied as a remediator to rescue the pollution environment in the area of Bachimen fish cage-farming.The experiments were conducted in Dongshan island from August to December 2003.Water quality was monitored at fixed sites or sections or planes of different functional areas including bioremediation fish cage-farming and non-aquaculture during the experimental courses.The results showed that after the data collected from the areas of fish cage-farming and non-aquaculture were compared,G.lichenoides was effective in terms of uptakes of inorganic nitrogen and inorganic phosphorus,and improvement of the dissolved oxygen in the area of bioremediation on sunshine.In rainy weather,the effect of bioremediation was still obvious.While in the area of fish cage-farming, concentrations of inorganic nitrogen and inorganic phosphorus were higher and the concentrations of DO were apparently lower than that in the area of non-aquaculture.Especially,it was important to alleviate the self-pollution of fish cage-farming and G.lichenoides was prior to uptake ammonia of inorganic nitrogen.So it could avoid causing fish to death in the foul weather.Furthermore,the outputs of the bioremediatior G.lichenoides could be used as foods for abalones and thus enhance the total economic value of mariculture.This study also demonstrated an ecological approach for sustainable aquaculture.福建省重大科技项目(2002Y005)

Depression and affect of red tide on main water quality index by Gracilaria tenuistipitata

跟踪监测八尺门海区赤潮的消亡过程并在室内和海区进行实验,研究江蓠(Gracilariatenuistipitata)对赤潮的消亡和水质的影响。结果表明,江蓠可以加速中肋骨条藻赤潮的消亡,避免赤潮消亡后水体出现缺氧状态,减轻赤潮对环境的损害。采用室内模拟的办法,可以了解海区赤潮的发展趋势及赤潮消亡过程中溶解氧的浓度变化情况,为控制赤潮提供科学依据。A red tide in Bachimen sea area was monitored and the experiments of indoor and in the field were carried out to study depression and the effects of Gracilaria tenuistipitata on red tide main water quality index. The results showed that Gracilaria tenuistipitata might accelerate red tide depression and avoid DO depression, as well as reduce the environmental damage. It was hinted that indoor experiment could be a method for understanding the trends of red tide and DO, and providing data for red tide control.福建省自然科学基金重大项目(2002Y005