Impact of lake‐catchment processes on phytoplankton community structure in temperate shallow lakes

Abstract

Research on lake-catchment and biological processes is still innovative. Few reports on this topic exist in the scientific literature. This paper presents species richness, diversity, biomass composition of phytoplankton, and occurrence of cyanobacterial blooms in relation to complex lake-catchment processes in four shallow lakes. The results revealed that phytoplankton species richness increased with increasing lake trophic state, whereas the opposite relationship was observed for phytoplankton biodiversity. In less eutrophic and deeper lakes, the majority of dominant taxa were representatives of mixed, meso to eutrophic small-and medium-sized lakes. In highly eutrophic lakes, the dominant taxa were common representatives of shallow, very rich in nutrients, turbid, mix layers, and eu-hypertrophic environments. Redundancy analysis showed that lake depth, flushing time, and conductivity were the most significant factors for phytoplankton development and composition. The hypertrophic, polimictic, and flow-through Lake Syczyńskie was the most dynamic ecosystem among the lakes. Water mixing and high concentrations of P-PO 4 were beneficial for heavy blooms of the cyanobacterium Planktothrix agardhii observed in Lake Syczyńskie despite the high rate of water exchange. Contrary to the findings of some previous studies, P. agardhii seems to be resistant to flushing at very high loads and concentrations of nutrients (mostly of P-PO 4 and N-NO 3 ). Phytoplankton assemblages reflected the lakes' habitats, trophic status, and lake-catchment processes and revealed complex factors that influenced the lakes' functioning. The use of phytoplankton as an indicator of lake-catchment processes may help understand ecosystem dynamics, essential for the proper selection of management practices protecting aquatic systems against eutrophication.

An over 200-Year Environmental Change Record from the Highly Impacted Small, Hardwater Lake Pniówno (Chełm Hills)

“…This effect is stressed by Ferencz and Dawidek (2014), who also highlight its role in shaping lake water quality. The results of comprehensive hydrochemical measurements points also to the important role of fl ushing time for Lake Pniówno's ecological status (Ferencz, Dawidek 2014;Toporowska et al 2018). Therefore, the major change in the surface hydrological network which was the inclusion of Lake Pniówno in the surface drainage network via Nagórnik ditch, resulted not only in the lowering of water level, but, most probably, via shortening of the retention time, also deeply affected reaction to groundwater supply.…”

“…1 and 2. The lake's small area and volume, as well as the catchment area predominated by agricultural land use and rural settlement, place the lake among water bodies of high eutrophication risk (Toporowska et al 2018). In 1950, the aquatic macrovegetation was scarce, with presence of stoneworts (Chara fragilis, Chara intermedia), watermilfoil Myriophyllum verticillatum, and, among the nympheids, pondweed Potamogeton natans, Nuphar luteum and Nymphaea candida.…”

“…The lake was surrounded by the belt of emergent vegetation with cattail Typha angustifolia and reed Phragmites australis (Fijałkowski 1959, only one stonewort and three submerged macrophyte species were encountered with strong predominance of hornwort Ceratophyllum demersum and scarce presence of water soldier Stratiotes aloides (Sugier et al 2010). Extensive phytoplankton development in the lake has been observed in recent years -summer phytoplankton blooms are mentioned by Sugier et al (2010) and blue-green algae blooms -by Toporowska et al (2018). Nowadays, the lake is supplied by small man-made tributaries, and one large outfl ow (Nagórnik ditch) discharges water towards the east, to the Lepietucha River, and, subsequently, to the Uherka River.…”

“…1953 AD (1) 2008-2010 AD (2) Lake Radwan et al [1971;1972;1973], based on single measurement -19.05.1967; (2) Sugier et al [2010], based on single measurement, summer season; (3) Toporowska et al [2018], seasonal measurements during the vegetation season -spring, summer, autumn: mean, range) Parameter 1967 AD (1) 2006-2007 AD (2) 2008-2010…”

Temporal and Vertical Relations between Various Environmental Factors in the Largest Lake of Łęczna-Włodawa Lake District (Eastern Poland)

“…In recent decades, global warming and increasing water eutrophication have become a reason for investigation of different in-lake and catchment-lake processes [1]. A temporal and spatial heterogeneity of environmental parameters (temperature, oxygen concentration, pH, etc.)…”