水华藻斑漂移速度时变特征研究

以太湖水华藻斑为研究对象，采用自主研发的藻斑漂移原位观测技术，研究分析了不同时间尺度下太湖蓝藻水华易发区藻斑漂移速度的变化特征.结果表明：日内藻斑漂移速率在（0.0793±0.0135）~（0.146±0.0318）m/s范围内变化，藻斑漂移速度的北向分量在-0.0896~0.0247m/s之间，东向分量在-0.0157~0.0029m/s之间.漂移速率日均值变化呈现出锯齿式交替特征即增加-减少-再增加的往复循环，变化范围为（0.0499±0.0141）~（0.1580±0.0120）m/s，漂移方向以北向为主.藻斑漂移速度的月际变化明显，6月~8月，向东漂移的占比逐渐降低，而向西漂移的占比逐渐增加，此期间漂移方向均以北向为主.漂移速率6月上旬最小，均值为0.0680m/s，7月上旬达到最大，均值为0.1350m/s，7月中旬~8月下旬水华藻斑漂移速率在0.0800m/s附近波动.

Study on horizontal drifting velocity characteristics over time-varying of algal patches

Driven by the external power, floating algal patches in the open Taihu Lake would drift into Meiliang Bay and Zhushan Bay located in the northern part of Taihu Lake. And the input of exogenous algal patches would aggravate the outbreak of algal blooms in local areas. Based on the self-developed situ observation technique of algal patches drift. We investigated the variation characteristics of algal patches horizontal drifting velocity at different time scales in Zhushan Bay, Lake Taihu. The results showed that the diurnal variation range of algal drift ratewes (0.0793±0.0135)~(0.146±0.0318)m/s during the period of observation, and the eigenvalues of the northern and eastern component of drifting velocity of algal patches were -0.0896~0.0247m/s and -0.0157~0.0029m/s, respectively, which reflected significant time difference. The daily mean value of the drift rate based on situ observation exhibited a zigzag alternating characteristic, that was, an increase-decrease-re-increment reciprocating cycle, with a variation range of (0.0499±0.0141)~(0.1580±0.0120)m/s, and the drift direction was mainly northward. The inter-monthly variation of algal patches horizontal drifting velocity was obvious, From June to August, the proportion of drift to the east gradually decreased, while the proportion of drift to the west gradually increased. During this period, the drift direction was mainly northward. The drift rate of the algal blooms was the smallest in early June, with an average of 0.0680m/s. It reaches the maximum in the first half of July, with an average of 0.1350m/s. The drift rate from mid-July to late August fluctuated around 0.0800m/s.