State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu, 210023, China.
Bull Environ Contam Toxicol. 2022 May;108(5):943-948. doi: 10.1007/s00128-022-03470-1. Epub 2022 Feb 6.
DGT (diffusive gradients in thin films) technique has been developed for measuring nitrogen in freshwaters and applied to assess the bioavailability of phosphorus in soils/sediments. These two elements are the main nutrients causing algae bloom, but DGT has never been used in the field water conditions with algae bloom. In our study, a pair of DGT devices were used in comparison with grab sampling to characterize the performance of this technique to measure labile NO-N, NH-N, and PO-P concentrations in algae-cultivated Taihu Lake water. The results showed that DGT measurement was highly affected by algae bloom and the environmental conditions using the current assemblies, especially for NH-N measurement. For in situ measurement of nutrients in the real environment, an improvement to the DGT technique is required. The comprehensive assessment of the level of eutrophication needs to consider a variety of environmental factors rather than just the concentration of nutrients.
DGT（薄膜扩散梯度）技术已被开发用于测量淡水氮，并应用于评估土壤/沉积物中磷的生物有效性。这两种元素是导致藻类大量繁殖的主要营养物质，但 DGT 从未在藻类大量繁殖的野外水域条件下使用过。在我们的研究中，一对 DGT 设备与抓斗采样进行了比较，以评估该技术测量藻类养殖太湖水中的可利用 NO-N、NH-N 和 PO-P 浓度的性能。结果表明，DGT 测量受到藻类大量繁殖和当前组件使用的环境条件的高度影响，特别是对于 NH-N 测量。对于实际环境中营养物质的原位测量，需要对 DGT 技术进行改进。综合评估富营养化水平需要考虑多种环境因素，而不仅仅是营养物质的浓度。
