Phytoplankton from Vam Co River in Southern Vietnam

Abstract

<p class="emsd"><span lang="EN-GB">In this study we investigated the variation of phytoplankton and the water quality in Vam Co River, Southern Vietnam. Phytoplankton were bi-monthly monitored in 2011 at 12 sampling sites in the river. Some basic environmental parameters were also monitored including temperature, pH, turbidity, inorganic nitrogen and dissolved phosphorus. The phytoplankton biodiversity and Diatomeae indices were applied for environmental quality evaluation. The results showed that temperature </span><span lang="EN-GB">ranged from 28.7 – 31.9 </span><span lang="EN-GB">°C during the monitoring. The pH and turbidity were in between 3.9 – 7.0 and 2 – 64 NTU, respectively. The nitrate and ammonium concentrations were from 0.06 – 1.21 and 0.03 – 1.15 mg/L, respectively. The phosphate concentration was between 0.02 and 0.37 mg/L. </span><span lang="EN-GB">The environmental parameters were favorable for phytoplankton development. The phytoplankton analyses showed that there were 290 species of diatoms, green algae, golden algae, yellow algae, euglenoids, dinoflagellates and cyanobacteria of which green algae and diatoms were dominant in species number. </span><span lang="EN-GB">Phytoplankton density ranged from 920 – 383 600 individuals/L with the main dominant species of diatoms. The biodiversity index values during the monitoring were from 0.15 – 3.80 characterized for oligotrophic to eutrophic conditions whereas the Diatomeae index values were more than 0.2 indicating for the eutrophic characteristic of the aquatic environment. Besides, phytoplankton species number positively correlated with temperature but negatively correlated with nitrate concentration. Additionally, the biodiversity positively correlated with temperature and species number, but negatively correlated with nitrate and phytoplankton abundance. The results confirmed the advantage of using phytoplankton and their indices for environmental monitoring and water quality assessment.</span></p><p> </p>

Phytoplankton diversity and its relation to the physicochemical parameters in main water bodies of Vinh Long province, Vietnam

“…The average temperature of the main water bodies in Vinh Long province ranged from 28.5 to 29.9°C which was similar to the water temperature of some other water bodies in Southern Vietnam. This temperature offered favorable conditions for the development of phytoplankton (Dao & Bui, 2016). The environmental parameters of such as pH, dissolved oxygen, nitrate, phosphate were investigated and compared to the National technical regulation on surface water quality QCVN 08:2015/BTNMT.…”

Relationship between Phytoplankton and Environmental Variables from Bien Ho and Lak Lakes in Central Highland of Vietnam

“…Duong et al (2013) reported the correlation between phosphorus concentration and abundance of cyanobacteria. Dao and Bui (2016) noted the phytoplankton species richness positively correlated with temperature but negatively correlated with nitrate concentration. The same author showed the biodiversity positively correlated with temperature and species number, but negatively correlated with nitrate and phytoplankton abundance.…”

“…7, No. 2 2013; Dao and Bui, 2016). Interestingly, water temperature in Bien Ho and Lak Lakes in central highland ranged between that from the two regions of Vietnam, from 23 -28 º C (Table 1, 2).…”

“…In addition, golden and yellow algae and dinoflagellates were less diverse groups in both Bien Ho and Lak Lakes which could be explained as the meso-eutrophic conditions of the lakes were not favorable for development of the algae found in the current study, Dinobryon, Mallomonas, and Tribonema, which are characterized for clean water or oligotrophic condition (APHA 1998;Wetzel 2001). Besides, that Diatoms in the two lakes was lower in species richness should relate to the lentic water characteristics of the Bien Ho and Lak Lakes which are not as suitable as running water conditions for Diatoms' growth (Dao and Bui 2016). Again, both Bien Ho and Lak Lakes had less species number in dry season and higher species number in trans-season period (Table 4).…”

“…The correlation between phytoplankton abundance and dissolved nitrogen and temperature in Tuyen Lam Reservoir was found by Tran et al (2015). In Southern Vietnam, Dao and Bui (2016) reported the variation of phytoplankton and the correlation between species number, biodiversity and environmental parameters in Vam Co River. Recently, described that cyanobacterial biomass correlated to temperature, pH, biochemical oxygen demand (BOD 5 ) and inorganic nitrogen concentration in Tri An Reservoir.…”