Abiotic characteristics and microalgal dynamics in South Africa's largest estuarine lake during a wet to dry transitional phase

Nunes, Monique; Adams, Janine B.; Bate, G. C.; Bornman, Thomas G.

doi:10.1016/j.ecss.2017.09.009

Cited by 8 publications

(8 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rapid interchange between communities (i.e. resuspension) and low water residence time has previously been shown to hinder microalgal growth in the estuary in a wet phase (Nunes et al, 2017). The lower MPB biomass observed on Day 21 in this study can therefore be assigned to reduced community stability during more turbulent hydrological conditions, i.e., elevated freshwater inflow (Snow, 2016), coupled with wind-driven circulation (Bate et al, 2013).…”

Section: Discussionmentioning

confidence: 51%

“…A recent study by Nunes et al (2017) showed the nutrientenriched nature of the Mfolozi River inflow; however, none of the expected eutrophic responses associated with anthropogenic nutrient loading (e.g., accelerated phytoplankton growth and the proliferations of harmful/toxic algal blooms) were recorded (Lemley et al, 2015;Lemley et al, 2017). This response has also been observed in other estuaries such as the Marano and Grado Lagoon in the Mediterranean (Acquavita et al, 2015) and the Patos Lagoon in southern Brazil (Odebrecht et al, 2015) where, despite nutrient enrichment, altered water residence times inhibited net algal growth rates and biomass accumulation.…”

Section: Introductionmentioning

confidence: 99%

“…Phytoplankton and diatom communities are often used as indicators of ecosystem health because they are the major primary producers in aquatic ecosystems and are also generally the first to respond to anthropogenic disturbances (Rodriguez and Pizarro, 2015;Lemley et al, 2016). Therefore, due to the increased freshwater inflow that led to phytoplankton biomass dilution and resuspension of benthic diatoms, the use of artificial substrates as a monitoring tool has been recommended (Nunes et al, 2017). The benefits of using artificial substrates include standardized comparisons among sampling sites (Dela-Cruz et al, 2006), high accuracy in the measurements (Sanchez et al, 2017), uniformity of the surface, decreased habitat disruption (Dalu et al, 2014) and the development of a diatom community exclusively influenced by water column chemistry (Desrosiers et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The use of epilithic diatoms grown on artificial substrata to indicate water quality changes in the lower reaches of the St Lucia Estuary, South Africa

Nunes

Adams

Bate

2019

WSA

Self Cite

View full text Add to dashboard Cite

In shallow estuaries, artificial substrates provide a means of assessing the response of the diatom community to water chemistry. The shallow St Lucia Estuary was historically connected to the Mfolozi River at the mouth. This connection was severed during the early 1950s due to sediment input from the agriculturally impacted Mfolozi River. A connection has recently been re-established and the potential impact of dissolved inorganic nutrients from the Mfolozi River needs to be determined, as it may alter the ecological integrity of the St Lucia Estuary which forms part of a UNESCO World Heritage Site. This study found that the epilithic algal biomass and diatom species composition grown on glass slides were good indicators of nutrient enrichment in the estuary. Over a 28-day study period an above-average rainfall event resulted in an increase of nutrient-enriched freshwater flow into the estuary. No significant biomass differences were recorded in either the natural phytoplankton or microphytobenthos communities because of high variability. By contrast, the epilithic algal biomass accumulation on the glass slides was highest following the freshwater input. Statistical analyses indicated that the accumulation of the epilithic community on the glass slides was mostly affected by DIN and salinity. Diversity index scores for both the natural phytoplankton and microphytobenthos were variable, while the epilithic diatom index scores consistently declined from Day 7 (H’ = 1.2) to Day 28 (H’ = 0.7). These data indicate that epilithic algae grown on glass slides can be used as an effective monitoring tool to detect nutrient-induced changes as a supplementary method in this highly variable estuary.

show abstract

Section: Discussionmentioning

confidence: 51%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The use of epilithic diatoms grown on artificial substrata to indicate water quality changes in the lower reaches of the St Lucia Estuary, South Africa

Nunes

Adams

Bate

2019

WSA

Self Cite

View full text Add to dashboard Cite

show abstract

“…Algae are the primary producer of aquatic ecosystem, and play a key role in material cycling and energy transformation processes [1]. The planktic algae can transform inorganic materials into organic materials via solar energy, and the produced organics are then stored by consumers, which ensured the existence and propagation of algal community [2].…”

Section: Introductionmentioning

confidence: 99%

“…Note:1) Cya: Cyanobacteria; Din: Dinophyta; Bac: Bacillariophyceae; Chl: Chlorophyta; Eug: Euglenozoa. 2) N:P: the ratio of nitrogen and phosphorus.…”

mentioning

confidence: 99%

Understanding the Ecological Response of Planktic and Benthic Epipelic Algae to Environmental Factors in an Urban Rivers System

Xia

Zhu

Zhao

2020

Water

View full text Add to dashboard Cite

Many studies have been concentrated on the distribution of algae in lakes, rivers, and seas, however, few studies have been concerned about their distribution and relation with polluted urban rivers. In this study, the spatio-temporal variation characteristics of water quality and algae community in Nanjing city were investigated with microscopic examination for one year. Results showed that the water pollution in this area was mainly related to high concentration of nitrogen (NH3-N and TN (Total nitrogen). There was a total of 77 species of algae in the studied rivers from June 2016 to May 2017, among which 73 species of planktic algae and 34 species of epipelic algae, in which the abundance and biomass of the latter were 1925 and 904 times that of the former, respectively. The two kinds of algae had different change tendencies which were related to seasons. For planktic algae, the abundance and biomass decreased in this season sequence: summer, spring, autumn, and winter. For epipelic algae, the abundance and biomass were relatively higher in winter. The dominant community of planktic algae was Chlorophyta-Bacillariophyceae-Cyanobacteria type, while that of epipelic algae was Bacillariophyceae—Cyanobacteria type. Most of the present algae were bi-trophic species, and were tightly related to the pollution characteristics of the rivers. The key environmental factors for planktic algae are T, TN, and TP, and those for Epipelic algae are N:P and TN. The relation between the community composition of planktic and epipelic algae and environmental parameters are highly complex, and it is worth carrying out further study to clarify their interaction mechanism.

show abstract

Benthic Diatom Diversity and Eutrophication in Temporarily Closed Estuaries

Nunes

Lemley

Adams

2022

Estuaries and Coasts

View full text Add to dashboard Cite

Abiotic characteristics and microalgal dynamics in South Africa's largest estuarine lake during a wet to dry transitional phase

Cited by 8 publications

References 48 publications

The use of epilithic diatoms grown on artificial substrata to indicate water quality changes in the lower reaches of the St Lucia Estuary, South Africa

The use of epilithic diatoms grown on artificial substrata to indicate water quality changes in the lower reaches of the St Lucia Estuary, South Africa

Understanding the Ecological Response of Planktic and Benthic Epipelic Algae to Environmental Factors in an Urban Rivers System

Benthic Diatom Diversity and Eutrophication in Temporarily Closed Estuaries

Contact Info

Product

Resources

About