| 摘要: |
| 分别在室内培养箱、海滨室外跑道池和不同自然海区,通过一次性和半连续添加营养、以及检测海区水质和藻体生长的方法,研究了不同氮浓度、温度和氮磷比条件下,长心卡帕藻氮吸收速率的变化和氮吸收速率随时间变化,以及栽培该藻的环境生态贡献。小型实验、中试放大和海区规模栽培结果表明:(1)在10-50μmol/L范围内,该藻吸收氮速率随氮浓度增加而增大;(2)当氮浓度一定时,氮磷比在1-50范围内对该藻吸收氮速率没有产生显著影响(P > 0.05);(3)温度对该藻吸收氮速率有显著影响P < 0.05),其中温度在28°C时氮的吸收速率最高;(4)尽管一次性添加营养实验中长心卡帕藻吸收氮速率随时间变化表现出先快后慢的趋势,但是进一步的半连续添加营养实验证实,导致吸收速率下降系底物氮浓度限制,而不是藻本身吸收能力下降,结果还显示卡帕藻具有连续吸收同化无机氮能力;在自然光温度变化和不受底物浓度限制条件下,该藻藻体去除无机氮效率最大维持在0.3μmol/(gFW?h);(5)海南陵水黎安海湾水质数据显示,栽培该藻去除海水富营养化和净化水质作用显著,其去除海水富营养化的年贡献为33t氮素。 |
| 关键词: 长心卡帕藻 氮吸收速率 温度 氮浓度 栽培 |
| DOI：10.11693/hyhz200805016 |
| 分类号: |
| 基金项目:国家海洋公益项目资助,200705010号;中国科学院方向性创新项目资助,L48032409D号;国家自然科学基金项目资助,30771639号 |
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| EFFECTS OF TEMPERATURE, NITROGEN CONCENTRATION AND N/P RATIO ON N UPTAKE RATES OF KAPPAPHYCUS ALVAREZII |
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LIU Jian-Guo1, LU Ke-Guo1,2, LIN Wei1, PANG Tong1, WANG Li1
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1.R & D Center of Marine Biotech, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071;2.Graduate School, Chinese Academy of Sciences, Beijing, 100049
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| Abstract: |
| Kappaphycus alvarezii, a kappa-carrageenan enriched red marine alga, were cultivated indoor in flask bottles and outdoor in open runaway ponds in Sanya, and Li’an Bay in Lingshui, Hainan. The effects of temperature, nitrogen concentration and N/P ratio on N uptake rates of K. alvarezii and temporal variation of the rate were studied in batch with semi-continuous adding of different concentrations of nutrients (the proportion of NH3-N:NO3-N:NO2-N was 10:10:1 quite close to that of local natural seawater), and the environmental remediation to large scale cultivation of K. alvarezii in tropic marine was estimated. The results showed that the N uptake rates of K. alvarezii improved with the increase in initial dissolved inorganic nitrogen (DIN) in range of10-50 μmol/L. However, 100 μmol/L DIN inhibited the N uptake rates due probably to ammonia toxicity, especially when this seaweed incubated at high temperature and strong natural sunshine. The DIN uptake rates were independent on N/P ratio in range of 1-50 (P > 0.05). Temperature influenced significantly the N uptake rates (P < 0.05), and the highest DIN uptake rate occurred at 28°C with high growth rate. The DIN uptake surged in the first hour and then slowed down in batch culture due to substrate deficiency instead of the gradual weakening uptake ability of the algae. In fact, the DIN uptake ability was well maintained without DIN limitation for a long period, as shown clearly in our experiment. The maxima DIN uptake ability exposed to natural tropic sunshine and temperature was about 0.3 μmol/(gFW*h) with enough DIN supply. DIN concentration obviously decreased once eutrophicated seawater flowed through the cultivation area in Li’an Bay, demonstrating that the algae were able to absorb N for purifying marine seawater. By calculation, in Li’an Bay, at least 50t of fresh K. alvarezii could be harvested daily, and about 1100t of fresh K. alvarezii biomass could be raft cultivated annually, which would be about 33t of nitrogen or equally 72t urea removal from the bay. Therefore, cultivation of K. alvarezii was not only feasible for carrageenan production, but also eco-friendly to the environment to ease eutrophication. |
| Key words: Kappaphycus alvarezii, Nitrogen uptake rate, Temperature, Nitrogen concentration, Cultivation |
