1. ABSTRACT METHODS RESULTS BACKGROUND CONCLUSIONS OBJECTIVES
Effects of Phosphate Spill on Water Quality Parameters in The Grand Bay National Estuarine Research Reserve Taimei T. Harris, Luma Akil, and H. Anwar Ahmad Dept. of Biology/Environmental Science, College of Science, Engineering, and Technology, Jackson state University, Jackson, Mississippi 39217, USA
ABSTRACT
METHODS
Water quality describes chemical, physical, and biological characteristics of water, specifically for human consumption and for animal, plant, and agricultural usage. Water quality is measured by several factors, such as the concentration of dissolved oxygen, pH, the amount of salt (salinity), temperature, or the amount of material suspended in the water (turbidity). Raw data for this research were collected from the National Estuarine Research Reserve (NERR) Centralized Data Management Office website ( under the station code GNDBLWQ, from , to understand seasonal variations over a decade and long term effects of natural disasters. NERRS released this water quality data for public access in October 12, The mean seasonal, monthly, and annual pH were (7.80 ± 0.18), (7.75 ± 0.16), and (7.74 ± 0.28) respectively. Results indicated significant (p<0.05) seasonal, monthly, and annual differences. This research is a significant step in understanding the effects of poor water quality on health risks of ecosystems.
Figure 2: The statistical analysis was completed using SAS with year, month, and seasons as the independent variables and the water quality parameter pH as the dependent variable.
RESULTS
Table 1: Statistical parameters for monthly and yearly water quality parameters
MONTH
Mean ± SDev
YEAR
JAN
8.09± 0.21%
2004
7.7±0.18%
FEB
8.04± 0.28%
2005
7.64±0.22%
MAR
7.94± 0.19%
2006
7.74±0.25%
APR
7.74± 0.17%
2007
7.77±0.24%
MAY
7.59± 0.11%
2008
7.84±0.34%
JUN
7.5± 0.09%
2009
7.79±0.38%
JUL
7.51± 0.1%
2010
7.82±0.32%
AUG
7.53± 0.18%
2011
7.71±0.26%
SEPT
7.46± 0.13%
2012
7.64±0.29%
OCT
7.65± 0.09%
2013
7.83±0.340%
NOV
7.89± 0.21%
2014
7.74±0.34%
DEC
8.05± 0.25%
2015
7.69±0.17%
BACKGROUND
Grand Bay National Estuarine Research Reserve (GBNERR) covers approximately 18,000 acres and consists of four sampling sites (Bayou Heron, Bayou Cumbest, Bangs Lake, and Point Aux Chenes Bay).
On April 14, 2005, a catastrophic pollution spill occurred at Bangs Lake, a tidal lake within the GBNERR in Mississippi. The disaster occurred when wastewater filled walls of retaining ponds collapsed at a Mississippi Phosphates (a fertilizer manufacturing company) located 1.1 km (0.7 mi) from the lake. Relatively 17.5 million gallons of polluted water flowed from the retaining ponds and into Bangs Lake.
The wastewater released had a pH of 2.2 to 2.4 and contained elevated levels of phosphorus ppm. The spill contaminants, calcium sulfate and wastewater (contaminated with phosphoric acid and other pollutants) are sources of waste that come from the creation of phosphates for fertilizer. Furthermore, phosphate ore is reacted with sulfuric acid to produce phosphoric acid in order to get useable phosphate for fertilizer.
Figure 3: Monthly changes and trends in pH
Figure 4: Yearly changes in pH with significant decreases in 2005 and 2012
CONCLUSIONS
Figure 1: Large areas of marsh vegetation died as a result of the April 14, 2005 phosphate spill. The pervasive algal blooms occurred in the shallow, enclosed waters near the point where the polluted water entered Bangs Lake. These hypoxic conditions contribute to the stress and death of various forms of life.
According to Liebetrau (1979), understanding long-term variations in selected water quality parameters represents one of four necessities of water quality monitoring.
Long-term trend of water quality in natural systems reveal information about chemical and biological changes and variations due to man-made and/or seasonal interventions.
The time series of daily measured values of water quality parameters (pH) over ten years ( ) were used for monthly, seasonal and annual analysis.
The monthly results indicated that significant trends were detected in pH data. With majority of the yearly trends being insignificant at the 5%. Meanwhile, the highest numbers of significant trends were detected in the winter seasons. In contrast, no significant positive or negative trends were found in fall or spring water quality data.
OBJECTIVES
To analyze water quality and nutrient data to identify seasonal variations in pH and changes, since the 2005 phosphorus spill.
To observe the trends in the pH over time.
To explain how the water chemistry of an estuary affects the health of the estuarine ecosystem.
Acknowledgments: This work is supported by the National Institute on Minority Health and Health Disparities of the National Institutes of Health under Award Number G12MD and by the Mississippi INBRE, funded by an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM The content is solely the responsibility of the authors and does not represent the official views of the National Institutes of Health.