Plankton characterization of alpine ponds: a case of study for the assessment of water quality in Serra da Estrela (Portugal)

Abstract

Serra da Estrela is Portugal's mainland highest mountain, with distinctive geological, climatic and geomorphological characteristics which play a key role on surface and groundwater resources. These mountains have the largest set of glacial ponds of Portugal and are scarcely studied. Besides, there are concerns of possible impacts of the use of salts in road de-icing on ponds' biotic communities. This research intends to characterize the hydrology of five Mediterranean alpine ponds and assess their planktonic communities. The biotic index proposed by the Water Framework Directive for lentic systems was used to check its applicability to these systems. Sampling was conducted monthly from June to November 2015 alongside with hydrological characterization. Water parameters and nutrients' content were quantified. Phytoplankton and macrozooplankton were identified. Ponds' water level is controlled by precipitation (input) and evaporation, infiltration and streamflow (output). Ponds were in good ecological quality. However, the current ecological assessment tools proposed by the WFD for lentic systems do not fit alpine ponds, showing a gap in the current methods. Salts used for road de-icing did not impact the communities and the ecological state of ponds. Phytoplankton was dominated by Cyanobacteria, Dinophyceae and Bacillariophyceae; Cyclopoida was the most abundant zooplanktonic group. For macrozooplankton, RDA shows association between cladocerans and phosphorus content. Phosphorus changes promoted shifts in zooplankton, what may be of major concern from a conservation point of view, once alpine ponds and its species are still mostly unknown. Efforts should be done to develop tools to classify aquatic ecosystems from harsh environments.

Assessment of Hydrobiological and Soil Characteristics of Non-Fertilized, Earthen Fish Ponds in Sindh (Pakistan), Supplied with Seawater from Tidal Creeks

“…Copepods were clearly the dominant group of zooplankton throughout the study period, and were consistently found every month. Similarly to that revealed here, the dominance of calanoids and cyclopoids in ponds has been described before, but specifically only in high-altitude lakes [2,100]. Copepods are able to tolerate high radiation in the summer thanks to the elevated concentration of carotenoid pigments, mycosporines, and mycosporines-like amino acids [101,102].…”

“…Similar observations were made in different studies focused on tropical ponds [65,86]. It should be mentioned, however, that the presence of ammonia may also be an important factor in the regulation of cyanobacteria in ponds [87], while alkalinity [65], phosphorus [2], and influx of other nutrients [88] are also very important for the proliferation of phytoplankton.…”

“…belonging to cyanobacteria. While diatoms are usually to be found in ponds during colder months, and their biomass is expected to increase under reduced light and temperature [81,82], cyanobacteria tend to grow faster at high temperatures and intense lighting [2,83]. It is known that Cyanophyta thrive in the summer because they produce UV-screening compounds which favor their growth at higher temperatures [84,85].…”

“…Plankton constitute an important role in the trophic chain, establishing the energy flow between primary producers and planktivorous fish and shellfish species [1,2]. Therefore, plankton have been deemed invaluable for a sustainable pond-based aquaculture, as the presence of abundant pond biota is necessary to fulfill the nutritional requirements of many farmed fish [3,4] and shrimp species [5,6].…”

A Preliminary Investigation of Phytoplankton and Zooplankton Diversity in Marine Water Ponds, Thatta, Sindh, Pakistan

“…The occurrence of zooplankton mainly influences the pelagic fishery potentials, like fish grow and survive in those areas where the planktonic organisms are abundant, so that their young ones can get sufficient natural food. Zooplankton indicates ecological condition because they respond changes in the nutrient level and fish population, while population of phytoplankton is totally depending on the numerous environmental factors and varying nutrient transport seasonally (Yaqoob et al, 2013;Martins et al, 2020). It is verified that, plankton fulfill the nutritional requirement of farmed fish and shrimp species and also indicate the productivity of water (Coutinho et al, 2012;Gamboa-Delgado, 2014).…”