控制汉江丹江口-王甫洲区间伊乐藻的生态调度及其效果评估

为科学有效控制汉江丹江口至王甫洲区间伊乐藻过度生长繁殖,研究生态调度的实施效果。采用生物量调查法、分布面积统计法、数学模型模拟法分别分析评价生态调度实施前后总生物量的变化情况,分布面积的变化情况,以及对丹江口水库下泄流量的需求。结果表明,连续三年实施生态调度,伊乐藻总生物量由2019年的4.8万t减少至2022年的40.11t,分布面积由11.60 km₂^减少至0.23km2,减幅均达到了95%以上, 伊乐藻生物量占沉水植物总生物的比重从99.99%减少至17%,生态调度效果较好。春季生态调度应重点从增加流量极值比出发进行中度干扰,夏秋季生态调度重点从满足0.14m/s临界流速出发进行大流速冲刷。

Ecological regulation and effectiveness evaluation of Elodea nuttallii controlling in the Danjiangkou Wangfuzhou section of the Hanjiang River

In order to scientifically and effectively control the excessive growth of Elodea nuttallii in the section from Danjiangkou to Wangfuzhou of the Hanjiang River, and to study the implementation effect of ecological regulation. The biomass survey method, distribution area statistics method, and mathematical model simulation method were used to analyze and evaluate the changes in total biomass, distribution area before and after the implementation of ecological regulation. Meanwhile, the demand for the discharge flow of Danjiangkou Reservoir is studied. The results showed that after implementing ecological regulation for 3 years, the total biomass of Elodea nuttallii decreased from 48000 tons in 2019 to 40.11 tons in 2022, and the distribution area decreased from 11.60 km₂ ^{to 0.23 km₂}, with a decrease of over 95%. The proportion of Elodea nuttallii biomass in the total biomass of submerged plants decreased from 99.99% to 17%, indicating a good ecological regulation effect. In spring, ecological scheduling should focus on moderate interference by increasing the extreme flow ratio, while in summer or autumn, ecological scheduling should focus on high flow velocity erosion by meeting the critical flow velocity of 0.14m/s.