摘要
浮萍类植物是污水生态工程处理技术中吸收转化氮磷等营养物质的重要植物类群 .氮磷是浮萍生长所必需的主要结构组成物质 ,因此浮萍生物量的增长速率决定了其对氮磷吸收转化的能力 .本研究采用序批式培养和连续式培养 2种方式探讨了细脉浮萍 (Lemnaaequinoctialis)和紫背浮萍 (Spirodelapolyrrhiza)在污水营养条件下的生长特性 ,并利用单种种群增长的Logistic模型对生物量的增长曲线进行了分析 .研究结果表明浮萍的鲜生物量和干重随时间变化的增长曲线具有“S”型特点 ,在特定的环境和营养条件下 ,单位面积上浮萍生物量的增长受密度的制约 .Logistic拟合的结果表明浮萍生物量的增长符合种群的Logistic增长规律 ,浮萍在有限环境中生物量有最大值 :最大承载量 ,当密度达到最大承载量一半时 ,其生物量的增长速率最大 .实验结果及模型分析结果均表明 2种浮萍在氨氮人工培养液中的生长速率比在硝酸氮培养液中低 .细脉浮萍生长速率及含水率均高于紫背浮萍 .
Duckweeds have an important potential in nutrient recovery from wastewater because of their rapid multiplication and high protein content in biomass. The growth rate of duckweed biomass has a direct relationship with nutrient removal and recovery. With laboratory experiments of batch culture and continuous culture, the growth curves of two duckweed species, Lemna aequinoctialis and Spirodela polyrrhiza,cultivated in different media were gotten and fitted by Logistic model. The effect of nitrogen on growth of duckweed was evaluated. Experimental results indicated that the growth curve had characteristic of sigmoidal shape and the growth rate had density-dependent characteristic. Results of statistical analysis demonstrated that Logistic model is suitable to describe the growth of single duckweed specie. The maximal growth rate from regression in medium with ammonia nitrogen was lower than those in medium with nitrate nitrogen. The maximal growth rate of Lemna aequinoctialis was higher than Spirodela polyrrhiza The paper also discussed the application of Logistic model in harvesting of duckweed biomass from wastewater.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2004年第6期59-64,共6页
Environmental Science
基金
国家重点基础研究发展规划项目 (G1999945 711)
