Feng Wei-Ying, Zhang Sheng, Jiao Li-Xin, Wang Sheng-Rui, Li Chang-You, Cui Feng-Li, Fu Xu-Jin, Zhen Zhi-Lei
College of Water Conservancy and Civil Engineering Inner Mongolia Agricultural University, Huhhot 010018, China.
Huan Jing Ke Xue. 2013 Jun;34(6):2176-83.
Samples in the sediments of Wuliangsuhai and Erhai Lake were selected, and the technologies of XAD-8 resins separation and three dimensional fluorescence excitation-emission matrix (3DEEM) spectra were applied, in order to study the bioavailability of dissolved organic nitrogen components to alage under the room cultivation. The obtained results showed that: (1) Average loss of DON and DOC from sediments was below 5% after dividing DON into different groups, which means the technology of XAD- 8 resins separation could be used in the study of DON components in the lake sediment. (2) Through 3DEEM analysis, hydrophilic and hydrophobic DON was dominated by protein-like and humic-like materials in the lake sediment, respectively. (3) Under the hydrophilic component condition, growth curves of algae tended to show an "S" shape with a straight upward trend in the sediments of Wuliangsuhai and Erhai lake,with the maximum algal density reaching 535.5 x 10(4) and 709.5 x 10(4) per milliliter, respectively. Meanwhile, the DON concentrations were significantly reduced after cultivation to 2.46 and 2.98 mg x L(-1), respectively, which suggests that hydrophilic DON in the lake sediment was the bioavailable organic nitrogen for alage. (4) Under the hydrophbic component conditions, growth curves of algae tended to show a "unimodal" shape in the sediments of Wuliangsuhai and Erhai lake,with the maximum algal density reaching 113.5 x 10(4) and 275.5 x 10(4) per milliliter,respectively. The DON concentrations were significantly reduced during the early cultivation period, and then kept stable in the late period, which suggests that the hydrophobic DON component bioavailable to alage was low in short-term, and the hydrophobic DON component had hardly any positive effect on the growth of algae.
选取了乌梁素海和洱海沉积物中的样品，并应用XAD - 8树脂分离技术和三维荧光激发 - 发射矩阵（3DEEM）光谱技术，以研究室内培养条件下溶解有机氮组分对藻类的生物有效性。所得结果表明：（1）将溶解性有机氮（DON）分为不同组后，沉积物中DON和溶解性有机碳（DOC）的平均损失低于5%，这意味着XAD - 8树脂分离技术可用于湖泊沉积物中DON组分的研究。（2）通过3DEEM分析可知，湖泊沉积物中亲水性和疏水性DON分别以类蛋白和类腐殖质物质为主。（3）在亲水性组分条件下，乌梁素海和洱海沉积物中藻类生长曲线呈“S”形且直线上升趋势，最大藻密度分别达到535.5×10⁴和709.5×10⁴个/毫升。同时，培养后DON浓度分别显著降低至2.46和2.98毫克/升，这表明湖泊沉积物中的亲水性DON是藻类可利用的有机氮。（4）在疏水性组分条件下，乌梁素海和洱海沉积物中藻类生长曲线呈“单峰”形，最大藻密度分别达到113.5×10⁴和275.5×10⁴个/毫升。培养前期DON浓度显著降低，后期保持稳定，这表明疏水性DON组分短期内对藻类的生物有效性较低，且对藻类生长几乎没有积极影响。
