Eutrophication Assessment in Noakhali Sadar Upazila Reveals Significant Spatial Variation in Pond Water Quality

Strategic Insights -

Research conducted at Noakhali Science and Technology University aimed to assess the trophic status and water quality characteristics of twenty ponds in Noakhali Sadar Upazila using the Carlson Trophic State Index (CTSI). The study collected data on key physical-chemical parameters, including temperature, pH, total dissolved solids, dissolved oxygen, electrical conductivity, and nutrient levels. The results showed a wide range of values for these parameters, with some ponds exhibiting trophic conditions from oligotrophic to eutrophic. Strong positive correlations were found between certain parameters, highlighting the complexity of nutrient dynamics and transparency in these aquatic systems.

Key Takeaways:

  • The Carlson Trophic State Index (CTSI) was used to assess the trophic status of twenty ponds in Noakhali Sadar Upazila, revealing significant spatial variation in pond water quality.
  • Key physical-chemical parameters measured included temperature (24-32 °C), pH (6.7-8.42), total dissolved solids (46-1604 ppm), dissolved oxygen (4.33-7.46 ppm), electrical conductivity (91-3208 S cm³), and nutrient levels.
  • CTSI values ranged from 38.31 to 68.38, indicating trophic conditions from oligotrophic to eutrophic, with Pond-8 approaching hypereutrophic status.
  • Strong positive correlations were found between TDS and EC (r=1.00), TDS and Secchi depth (r=0.63), and EC and Secchi depth (r=0.63).
  • Chlorophyll-a exhibited a positive correlation with temperature (r=0.57) and TP (r=0.52), while showing a moderate negative correlation with Secchi depth (r=-0.46).
  • The study highlighted the need for continuous monitoring to prevent nutrient over-enrichment and ecological degradation.
  • The research provided essential baseline data for informed water resource management and supported the implementation of sustainable practices to preserve the ecological health of pond ecosystems in the region.

Statistics:

  • Temperature: 24-32 °C
  • pH: 6.7-8.42
  • Total dissolved solids (TDS): 46-1604 ppm
  • Dissolved oxygen (DO): 4.33-7.46 ppm
  • Electrical conductivity (EC): 91-3208 S cm³
  • Total nitrogen (TN): 0.7-5.6 mg L⁻¹
  • Total phosphorus (TP): 1.6-122 g L⁻¹
  • Chlorophyll-a: 0.545-8.250 g L⁻¹
  • Secchi depth: 0.22-1.13 m
  • CTSI values: 38.31-68.38

Sources:

  • Romanian Journal of Ecology & Environmental Chemistry, 2025,7(1):8-20
  • doi-org.sdpl.idm.oclc.org/10.21698/rjeec.2025.101
  • Estfalia (publisher)
  • Asma Akter (researcher)
  • Protima Sarker (researcher)
  • Shiblur Rahaman (researcher)