A novel indicator for defining plain urban river network cyanobacterial blooms: resource use efficiency

Heliyon, Год журнала: 2022, Номер 8(10), С. e10601 - e10601

Опубликована: Сен. 21, 2022

Increasing eutrophication and climate change have led to heavy cyanobacterial blooms in water diversion sources (e.g., lakes, reservoirs), which can potentially cause algae-bearing spread downstream an urban river network via channels. Defining the extent of has become a novel concern management. In this paper, we investigated physicochemical algae community characteristics small, closed, network, JiangXinZhou (JXZ), Lake Taihu basin. We propose indicator, resource use efficiency (RUE), for defining JXZ, whose recreational drinking comes entirely from outside sources. The results show that JXZ's aquatic habitat conditions (mean temperature, total nitrogen concentration, phosphorus ratio) are highly suitable proliferation biomass during high-water period. RUE was used calculation shows strong relationship with density, means it be as index define degree blooms. findings indicate risk bloom is absent when less than 46.81; appear bodies reaches up 106.68. This work provides theoretical support sustainable regional resources.

Язык: Английский

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Blooms and flows: Effects of variable hydrology and management on reservoir water quality

Ecosphere, Год журнала: 2023, Номер 14(3)

Опубликована: Март 1, 2023

Abstract Flow management has the potential to significantly affect ecosystem condition. Shallow lakes in arid regions are especially susceptible flow changes, which can have important implications for formation of cyanobacterial blooms. Here, we reveal water quality shifts associated with changing source inflow management. Using situ monitoring data, studied a seven‐year time span during inflows shallow, eutrophic drinking reservoir transitioned from primarily natural landscape runoff (2014–2015) managed flows larger upstream (Lake Diefenbaker; 2016–2020) and identified significant changes cyanobacteria (as phycocyanin) using generalized additive models classify bloom formation. We then connected chemistry occurrence blooms principal components analysis. Phycocyanin was greater years mesotrophic (2016–2020), but dissolved organic matter (DOM) specific conductivity, determinants quality, were greatest when dominated lake (2014–2015). Most notably, despite rapidly, it took multiple return consistent reduced level DOM after resumed, an observation that underscores how resilience may be hindered by weak resistance change slow recovery. Environmental rarely defined, yet show trade‐offs exist between poor via elevated conductivity higher risk, depending on source. Our work highlights importance not just quantity, security, our findings managers who must protect services while adapting projected hydroclimatic change.

Язык: Английский

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Capturing the rapid intra-day change of cyanobacteria bloom by land-based hyperspectral remote sensing in Lake Taihu

Journal of Lake Sciences, Год журнала: 2021, Номер 33(6), С. 1951 - 1960

Опубликована: Янв. 1, 2021

受蓝藻自身垂直迁移和频繁风浪扰动影响,太湖蓝藻水华漂浮混合和迁移堆积等变化迅速,在传统的湖面定位和断面监测中总感觉蓝藻水华有些来无影、去无踪,限制了对其形成过程、驱动机制和防控治理的深入认识.卫星遥感可以实现蓝藻水华空间分布同步观测,但由于观测频次的限制很难捕捉蓝藻水华快速动态变化过程.本文利用与杭州海康威视数字技术股份有限公司联合自主研发的陆基(地基、岸基或者平台、船舶、桩基等能固定安装的均可)高光谱多参数水质遥感监测仪,架设于中国科学院太湖湖泊生态系统研究站(简称太湖站)水上观测场,通过对叶绿素a浓度及其他关键水质参数秒-分钟级的连续观测,有效捕捉了一天内蓝藻水华短期突然和快速变化过程.研究结果显示,在微风和小风条件下蓝藻容易在表层水体漂浮,盛行西北风驱动湖面开敞水域蓝藻水华快速漂浮集聚到太湖站岸边,短短半小时内表层水体叶绿素a浓度可以由10 μg/L快速攀升到100 μg/L以上,一天内会出现多个叶绿素a峰值,清晰展示了蓝藻快速日内动态变化过程.受蓝藻快速日内变化影响,透明度、总氮、总磷和高锰酸盐指数等水质参数也呈现出快速日内变化,叶绿素a浓度与透明度存在极显著负相关,与总氮、总磷和高锰酸盐指数存在极显著正相关,叶绿素a能解释总氮、总磷80%以上的变化,说明蓝藻短期内的漂浮和集聚深刻影响到湖泊水质.;Due to the vertical migration of cyanobacteria and frequent wind waves disturbance, floating, mixing, accumulation bloom in Lake Taihu occur rapidly. It is very difficult accurately capture occurrence appearance using traditional lake positioning cross-section monitoring due low temporal spatial observation frequency resolution, which limits in-depth understanding formation process, driving mechanism, prevention control. Satellite remote sensing can realize synchronous distribution bloom, but it rapid dynamics limitation frequency. Using independently developed land-based (ground-based, shore-based, or fixed on platform, ship pile foundation) hyperspectral water quality instrument by Hangzhou Hikvision Digital Technology Co., Ltd Nanjing Zhongke Deep Insight Research Institute installed Laboratory for Ecosystem (TLLER) Chinese Academy Sciences, short-term sudden a day was effectively captured through continuous chlorophyll-a concentration other key parameters at second-minute level. The results show that are easy float surface under conditions breeze light wind, prevailing northwest drives open area accumulate shore TLLER quickly. Chlorophyll-a rapidly rise from 10 μg/L more than 100 just half an hour. Several peaks recorded 8:30 18:30. All these clearly have hourly dynamic change process. Affected variations cyanobacteria, such as secchi disc depth, total nitrogen, phosphorus chemical oxygen demand also variations. Significantly negative relationship between depth significantly positive relationships phosphorus, found, indicate floating gathering profound impact lakes.

Язык: Английский

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Off-shore and underwater sampling of aquatic environments with the aerial-aquatic drone MEDUSA

Frontiers in Environmental Science, Год журнала: 2022, Номер 10

Опубликована: Ноя. 16, 2022

Monitoring of aquatic habitats for water quality and biodiversity requires regular sampling, often in off-shore locations underwater. Such sampling is commonly performed manually from research vessels, or if autonomous, constrained to permanent installations. Consequentially, high frequency ecological monitoring, such as harmful algal blooms, are limited few sites and/or temporally infrequent. Here, we demonstrate the use MEDUSA, an Unmanned Aerial-Aquatic Vehicle which capable performing underwater inspection at up 10 m depth, composed a multirotor platform, tether management unit tethered micro Underwater Vehicle. The system validated task vertical profiling Chlorophyll-a levels freshwater systems by means custom solid sample filtering mechanism. This mechanism can collect two independent samples per mission pumping through pair glass-fibre GF/F filters. Chlorophyll measured deposits on filters consistent par with traditional methods, highlighting potential using UAAVs spatial resolution.

Язык: Английский

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A review of spatial structure of freshwater food webs: Issues and opportunities modeling within‐lake meta‐ecosystems

Limnology and Oceanography, Год журнала: 2022, Номер 67(8), С. 1746 - 1759

Опубликована: Июнь 9, 2022

Abstract Lakes are currently facing multiple anthropogenic stressors impacting their ecological communities. The best way to understand how these systems will be affected by the changing environment is modeling community dynamics. Models of lake food webs have tended focus on pelagic organisms and treat lakes as if they contain single, uniform However, heterogeneity in environmental conditions resource availability generates within‐lake compartmentalization web structure. Turnover among species interactions resulting from differences depth substrate type creates unique different regions lakes. Food within can therefore represented a three‐dimensional meta‐ecosystem, where compartments connected flows nutrients, materials, consumers with variable degrees mobility lake. We review spatially structured processes that connect parts ecosystem. then discuss current approaches address spatial communities, highlighting key methods some constraints preventing more explicit representation webs. Finally, we recommend use allometric trophic networks make easier. By capitalizing empirically described relationships parameterize trophically complex webs, balance generalizable model system‐specific needs. Given nature many threats freshwater lakes, building an understanding space structures imperative create better for management conservation.

Язык: Английский

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