芜萍生长对若干种元素的营养需求分析

摘要

[Objective] This study was to analyze the several nutrient elements de- manded for the growth of Wolffia globosa with the aim to provide references for the improvement on the formula of nutrient solution for the cultivation of Wolffia globosa. [Method] The basic conditions of the pond were simulated in the greenhouse, and nutrient solution was added to cultivate Wolffia globosa. The main element composi- tions of the experimental water, wild water and dried Wolffia globosa were detected by inductively coupled plasma spectrometer （ICP） and element analyzer, in order to study the nutrient demand for Wolffia globosa growth. And the absorption of N, P, K and consumption of P for the growth of Wolffia globosa were also analyzed. [Re- suit] The Wolffia globosa biomass of the experimental group which cultivated by adding nutrient solution increased over time, and after 2 weeks, the average capacity was significantly more than initial capacity; and the average capacity of the control group without nutrient solution was significantly lower than initial capacity, indicating that the addition of nutrient solution has obvious effect on the growth of Wolffia glo- bosa. However, the biomass of the experimental group was no longer increase after 2 weeks, indicating that there are some inhibitory factors in the incubators of the experimental group. The element detection results were as follows： the content pro- portions of N, P and K were 3.8：1：2.8, 11.5：1：17 and 5.2：1：6.8 in the experimental water, wild water and drying Wolffia globosa, respectively. The N, P, K in the water of experimental group was not exhausted, while the contents of Ca and Zn in three experimental incubators were below the limit of detection （ND）. And the contents of Mn in incubators No.l-No.3 were ND, 0.05 and 0.38 mg/L, respectively, presenting positive correlation with the biomass of Wolffia globosa. The inhibitory growth of Wolffia globosa is closely related with the absence of Ca, Mn and Zn in the nutrient solution. [Conclusion] The experimental results provided valuable parameters for the improvement on the formula of the original nutrient solution.%[目的]分析芜萍生长的元素需求，以期为芜萍培育中营养液配方的改良提供参考依据。[方法]在温室内模拟池塘基底条件，通过添加营养液培养芜萍，检测了培养终期水样、野外芜萍池塘水样及芜萍干样的8种元素成分，研究了芜萍生长所需的元素营养成分，并就芜萍生长中对N、P、K的吸收量与P消减量作了初步分析。[结果]添加营养液组的芜萍生物量均随时间延长逐渐增加，2周后收获量显著高于初始值；无添加组显著低于初始值，表明添加营养液具有显著效果。但营养液组芜萍生物量2周后不再增长且低于野外池塘，表明营养液组培养箱中可能存在某些抑制性因素。元素检测结果为；终期水样、野外池塘和芜萍干样的N、P、K的比例分别是3．8：1：2．8、11．5：1：17和5．2：1：6．8。培养终期营养液组3个培养箱的N、P、K等元素均有剩余，但是Ca、Zn均低于检出限；1-3号箱的锰离子含量分别为ND、0．05、0．38mg／L，与芜萍生物量呈正相关，试验中芜萍生长受抑制与培养液中Ca、Zn、Mn等元素缺乏密切相关。[结论]该研究结果为芜萍生长的营养液配方改良提供了有价值的参数。