摘要
近年来,我国黄海海域大规模暴发的绿潮现象对海洋生态环境和海水中的物质迁移转化产生了重要影响。而浒苔作为绿潮暴发过程中的主要藻类,是释放二甲基硫(DMS)的优势藻类,其对海水中硫酸盐吸收转化及生源硫释放发挥着重要作用。本文通过实验室培养探讨了温度、盐度及不同形态氮营养盐对浒苔生长及释放生源硫化物的影响。结果表明,在实验范围内(盐度为25—35,温度为20—25°C),盐度对浒苔生长无明显影响,但盐度增加会促进β-二甲基巯基丙酸内酯(DMSP)的合成。在温度为20°C盐度为35时,DMSP释放达到最大值。温度增加能够促进浒苔的增长,在培养第5天,25°C下浒苔湿重比20°C增加了25%左右。培养液中的DMS含量为20nmol/L左右,约是正常黄海水的4倍,DMSP的浓度更是高于正常海水的数十倍。增加无机氮浓度会促进浒苔的生长及DMS和DMSP的释放,相比之下,NH4+-N比NO3–-N更易被浒苔吸收利用,添加两种氮源组DMS和DMSP的最高含量均比空白组高60%和30%左右。DMS/DMSP的值在10%以内变化,培养过程中DMSP表观降解比AA(丙烯酸)/(AA+DMSP)总体上低于40%。
Outbreak of green tides in recent years in the Yellow Sea caused a negative impact on the local marine environment. As the major inductive algae of the green bloom, Ulva prolifera is a responsible alga for releasing dimethylsulfide （DMS）, which plays an important role in the biogenic sulfur transfer, sulphate absorption, and sulfur cycles in seawater. In a laboratory culture, we studied the effects of temperature, salinity, and nitrogen nutrient on the growth of U. prolifera and its biogenic sulfur production. In different experiment conditions （salinity： 25--35, temperature： 20--25~C）, salinity was not the main factor affecting the growth of U. prolifera. However, with the increase of salinity, the concentration of dimethylsulfoniopropionate （DMSP） increased and maximized at the condition of 20~C and salinity 35. The temperature increase promoted the growth of U. prolifera, and the wet weight of U. prolifera increased about 25% at 25~C compared with 20~C on Day 5. In addition, DMS concentration in the culture medium was about 20nmol/L, which is approximately 4 times of the control, while DMSP was even decoupled. Therefore, the addition of nitrogen nutrition could promote U. prolifera growth and the releases of DMS and other compounds. Meanwhile, NH4＋was found easier to be assimilated than NO3. The DMS and DMSP were about 60% and 30% higher in the nitrogen nutrient-enriched groups than that of the blank. The ratio of DMS/DMSP was lower than 10% and the ratio of AA/（AA＋DMSP）--the percentage of DMSP apparent degradation--was below 40%.
作者
谭婷婷
刘春颖
刘涛
许高宾
张磊
邓雪
陆小兰
TAN Ting-Ting;LIU Chun-Ying;LIU Tao;XU Gao-Bin;ZHANG Lei;DENG Xue;LU Xiao-Lan(Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Qingdao 266100,China;College of Marine Life Sciences,Ocean University of China,Qingdao 266071,China;Laboratory for Marine Ecology and Environmental Science,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266071,China)
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2018年第4期793-801,共9页
Oceanologia Et Limnologia Sinica
基金
国家自然科学基金项目
41676065号
中央高校基本科研业务费专项
201762032号
国家重点研发计划
2016YFA0601301号
2016YFC1402101号
青岛市民生科技计划
15-8-2-4-hy号
