The spatial ecology of phytoplankton blooms in UK canals

Abstract

13Environmental change is expected to increase the frequency and severity of problems 14 caused by harmful algal blooms. We investigated the ecology of phytoplankton blooms in UK 15 canals to determine the environmental predictors and spatial structure of bloom 16 communities. The results revealed a significant increase in bloom presence with increasing 17 elevation. As predicted, higher temperatures were associated with a greater probability of 18 blooms, but the relationship between temperature and bloom occurrence changed across 19 landscapes. At the minimum level of agricultural land, the probability of bloom presence 20 increased with increasing temperature. Conversely, at the maximum level, the probability 21 decreased with increasing temperature. This pattern could be due to higher temperatures 22 increasing phytoplankton growth rates despite lower nutrient concentrations at low levels of 23 agricultural land, and nutrient depletion by rapidly growing blooms at high levels of 24 agricultural land and temperatures. Community composition exhibited spatial autocorrelation: 25 nearby blooms were more similar than distant blooms. Hydrological distances through the 26 canal network showed a stronger association with community dissimilarity than Euclidean 27 distances, suggesting a role for hydrological connectivity in driving bloom formation and 28 composition. This new knowledge regarding canal phytoplankton bloom origin and ecology 29 could help inform measures to inhibit bloom formation. 30 31 Keywords: algal bloom, cyanobacteria, climate, land use, health, connectivity, canal 32 hypotheses using a novel data source which arises from a bloom reporting system in 131 operation in England. 132 133 METHODS 134 Land use data, including patterns of natural, agricultural, and urban land, were obtained from 135 the Land Cover Map (LCM) 2007

The effects of water chemistry and lock-mediated connectivity on macroinvertebrate diversity and community structure in a canal in northern England

“…Other studies have shown that hydrological connectivity is a crucial factor in predicting macroinvertebrate community structures (Gallardo et al 2008) and this hydrological connectivity has been shown to influence algal community structure in canals (Kelly & Hassall 2018). Taken together, these findings suggest that canal lock systems could be analogous to other hydrological networks and may provide an interesting testbed for ecological hypotheses about connectivity.…”

“…Additionally, while the flow of water is generally downstream, adhesion on canal boats and the action of bow waves result in some upstream movement (Liddle & Scorgie 1980). The action of locks may facilitate the transport of nutrients, pollutants and organisms between sections of a canal and there is evidence that hydrological connectivity across canal networks drives changes in algal community structure (Kelly & Hassall 2018). Furthermore, when a lock opens, the increased turbidity of the water elevates the concentration of dissolved oxygen, which has the potential to increase productivity and ecosystem function (Boets et al 2010).…”

Phytoplankton alpha diversity indices response the trophic state variation in hydrologically connected aquatic habitats in the Harbin Section of the Songhua River

“…Phytoplankton alpha diversity indices and trophic states in one aquatic habitat can be influenced by other connected aquatic habitats through water flow, transporting both nutrients and organisms 2 . Thus, phytoplankton alpha diversity indices and ecological traits tend to be similar among interconnected aquatic habitats in freshwater and ocean systems 3 , 10 , 11 . In contrast, phytoplankton alpha diversity indices become less similar among aquatic habitats with little or no hydrological connectivity.…”

Ecological quality and conservation status of inland waters

“…A second group of articles brings together 4 papers in which ecological monitoring and analysis permit the authors to propose local and international management and conservation measures. Two articles explore local ecological studies: one focused on ecology of phytoplankton blooms in United Kingdom canals, with the aim of helping to control harmful algal blooms (Kelly and Hassall 2018); and the other analyses the effects of agricultural activity and land use on streams of Andean Choco in Ecuador (Morabowen et al 2019). Both studies highlight severe human impacts and suggest management practices to avoid unwanted effects on biodiversity.…”