A Water Quality Analysis of the Lower Cove River Watershed After the Eradication of the Phragmites Australis
Alice Obas
West Haven High School
1 McDonough Plaza West Haven, CT 06516
1 March 2014
A Water Quality Analysis of the Lower Cove River Watershed After the Eradication of the Phragmites Australis
Alice Obas, 94 Edward St, West Haven, CT 06516
West Haven High School, West Haven, CT
Teacher and Mentor: Kevin Dickson/ Dr. Scott Graves
For the past 150 years, the concentration of the invasive Phragmites Australis has dramatically increased around North America and damaged many environments. The invasive species, unsuitable for most wetlands wildlife, dominated Cove River located in West Haven for a substantial amount of time. However, with the assistance of a grant from the Watershed Research Tidal Restoration Program, this detrimental species has been eradicated from the Cove River estuary. This research aimed to study the water quality of Cove River to determine whether the quality has in fact improved. Data collected for this investigation was compared to data obtained prior to the obliteration of the invasive species. Since the phragmites Australis posed great threat to the environment, it was hypothesized that the water quality would improve with its removal, making the environment more habitable than before. To ascertain exactly how habitable the environment was, the pH, dissolved oxygen level, temperature, phosphate and nitrate levels of Cove River along with the growth of experimental plants planted on the marshwere documented biweekly. After studying this data, a conclusion of the current state of the water quality was constructed, testing the hypothesis. This research overall sought to demonstrate the precise impact of the Phragmites Australis on the tidal wetland.
ACKNOWLEDGEMENTS
Firstly, I would like to thank Mr. Kevin Dickson, my AP Biology teacher (West Haven High School), for the opportunity to conduct this research. Without Mr. Dickson, I would not have been aware of the recent proceedings conducted at Cove River nor would I have had the chance to further investigate the issue. Mr. Dickson also provided the necessary equipment for my research and never hesitated to offer any advice. I would like to thank the Watershed Research Project and Mark Paine(City of West Haven, Public Works) for allowing me to study Cove River.I would also like to thank Dr. Scott Graves (SCSU faculty in Science Education & Environmental Studies) for his mentoring of me. Last but not least, I would like to give a big thank you to Elizabeth Fournier and the West Haven High School AP Biology class of 2014 for accompanying me during my research, providing additional necessary data, and their continuous support.
TABLE OF CONTENTS
Abstract…………………………………………………………………………………...2
Acknowledgements……………………………………………………………………….3
List of Tables……………………………………………………………………………..5
List of Figures…………………………………………………………………………….5
Introduction……………………………………………………………………………….6
Materials and Methods……………………………………………………………………9
Results……………………………………………………………………………….…...11
Discussions and Conclusions………………………………………………………….…12
References………………………………………………………………………………..17
LIST OF TABLES
TABLE 1The Treatment Process of the Cove River of West Haven 10
TABLE 2A Table of The Water Quality of Cove River (2008-2013)11
TABLE 3The Heights of Plants Over Time12
TABLE 4pH Results of Cove River (1996)15
LIST OF FIGURES
FIGURE 1Distribution of Phragmites Haplotypes in North America7
FIGURE 2Distribution Patterns over time in Connecticut, Massachusetts,
and Rhode Island8
FIGURE 3The Heights of Plants Over Time12
INTRODUCTION
Biological invasions pose a great threat to species and ecosystems worldwide. Not only do they affect the community and ecosystem functionings, but they also affect the genetic level to closely related species and local populations of the same species (Saltonstall, 2003). For the past century, the common reed, Phragmites Australis, has expanded dramatically across North America at an increasingly rapidpaceand has devastated various wetland communities (Saltonstall, 2003).
The perennial grass distributes cosmopolitanly, typically bordering lakes, ponds, and rivers while reproducing through vegetative growth via rhizomes (Saltonstall, 2002). The growth of phragmites has many significant effects on the invaded areas, and can directly alter the resources available to plants and animals (Meyerson, Saltonstall, Windham, Kiviat, & Findlay, 2000). For instance, Meyerson and colleagues found that “plant height, stem density, and detrital accumulation combine to reduce light at the mash surface soil and air temperatures within phragmites stand” (2000). These factors eventually inhibit the germination of other plant species as well as slow decomposition of organic material (Meyerson, Saltonstall, Windham, Kiviat, & Findlay, 2000). Because of the density of the phragmites stems and the slow rate of decomposition in the winter, after the stems die, a significant amount of combustible material remains, posing serious fire hazards in suburban areas (Capotosto & Wolfe, 2007). The establishment of non-phragmites plant species is further prevented by low light levels in phragmites stands as a result of a biomass accumulation that delays spring thawing of marsh substances (Meyerson, Saltonstall, Windham, Kiviat, & Findlay, 2000). Phragmites invasions also result in changes in animal populations and modified nutrient cycling (Meyerson, Saltonstall, Windham, Kiviat, & Findlay, 2000).
According to Saltonstall’s study of the phragmites’ genetics, eleven native haplotypes and one introduced haplotype occur throughout North America, with haplotype “M” being the most common type (2002). A haplotype is a “group of genes within an organism that was inherited together from a single parent” (“Haplotype,” 2013). The non-native haplotype has expanded its range throughout North America (Gucker, 2008). Fig. 1 below demonstrates the concentration of both the invasive haplotypes and the native haplotypes, before and after 1960, across the United States (Saltonstall 2002).
Fig. 1 Distribution of Phragmites Haplotypes in North America
Evident in the data from Saltonstall (2002), the distribution of the phragmites increased largely after 1960. The green triangles represent the eleven native haplotypes; the blue squares are one of the haplotypes, haplotype l; and the red circles represent the invasive haplotype M (2002). As can be seen in the figure, the invasive haplotype increased intensely after 1960. On the other hand, fig. 2 shows the changes in haplotype concentration of Connecticut, Massachusetts, and Rhode Island (2002).Again, it is seen that after 1960, the concentration of the invasive haplotype increased compared to years prior.
Fig. 2 Distribution Patterns over time in Connecticut, Massachusetts, and Rhode Island
Particularly in Connecticut, it has been found that the concentration of phragmites Australis in the New Haven area has increased in the past decades as a component of Connecticut tidal marshes (Capotosto & Wolfe, 2007).According to the statistics of Capotosto and Wolfe, approximately ten percent of Connecticut’s tidal wetlands are dominated by Phragmites (2007). This dramatic spread of phragmites may have been the result of disturbances such as sedimentation, and excavation (Capotosto & Wolfe, 2007). In effort to save the wetlands, the State of Connecticut Department of Environmental Protections Wildlife Division, Wetlands Habitat and Mosquito Management (WHAMM) Program has focused on the control of phragmites statewide since 1997 (Capotosto & Wolfe, 2007). Certain methods of control include: restoring salt-water tidal flows, and three-year herbicide application and mowing (Capotosto & Wolfe, 2007).
The increase of invasivephragmites in the New Haven area prompted the eradication efforts alongthe Cove River of West Haven, Connecticut. The presence of thephragmites in this area led to the disappearance of native plant species due to a lack of nutrients and light (Capotosto & Wolfe, 2007). This ongoing research following the eradication investigated whether the removal of the invasive has actually improved the water quality and the surrounding environment. There are two parts to this research; part A studies the water chemistry, such as the pH, temperature, as well as the nitrate, phosphate, and dissolved oxygen levels.Part B studies plant height in the marsh.Based on prior research of phragmites and its effects on ecosystems, it was expected that this removal would in fact improve the water quality. Preliminary results have indicated that the environment is habitable and continues to improve. The objective of the current research is to continue to obtain data during the upcoming years in order to form an ultimate conclusion of the exact effects of removing the invasive in the Cove River area.
MATERIALS AND METHODS
Water Quality
All data was measured using trademark Vernier materials provided by the West Haven High School Science Department. In order to test the temperature, pH level, dissolved oxygen levels, Vernier probes compatible with the LabQuest2 standalone interface were utilized. To measure the nitrate and phosphate levels, nitrate and phosphate caplets were used in a sample of 5ml of water. A color chart determined the presence of the chemicals and their level. Simple kits can be used to test the water qualities. The procedures followed mimicked those of the instructions provide in the kits. After gathering 5 mL of water into a closed capsule, a tablet was inserted then the capsule was inverted until the tablet dissolved. After waiting about five minutes, the color of the sample was observed. The color charts provided in the kits helped determine the levels of the phosphates and nitrates.
Following the tests, all water samples were given to the science safety officer for proper disposal.
Plant Growth
To test how habitable the environment was after the eradication of the phragmites; twelve experimental plants were stationed on the river/marsh. With every visit, the plants were measured in centimeters using a meter stick. The data was recorded and graphed in an excel spreadsheet.
General Procedures
All data was obtained at Cove River located behind West Haven High School. The tests were conducted mostly atsolar noon, around 4:00 pm to comply with GLOBE protocols. The data obtained was additionally recorded on the GLOBE web site to assist in international research.
Treatment Process
Table 1 below shows the different dates that the Cove River was treated and the different treatments that were done. The Imazapyr and Glyphosate are herbicides that were sprayed to kill the phragmites. The table shows the multiple dates that this removal was conducted as well as the amount of acres it was conducted on. Furthermore, a marsh master was used to mow mulch.
Table 1 The Treatment Process of the Cove River of West Haven
Treatment Type / Acres8/11/11 – 8/19/11 / 27 gal Imazapyr / 76
9/11/11 – 10/18/11 / 20 gal Glyphosate / 76
7/19/12 – 7/25/12 / 10 gal Imazapyr / 38
9/12/12 – 9/14/12 / 14 gal Glyphosate / 38
8/14/13 – 8/15/13 / 1.5 gal Imazapyr / 12
8/14/13 – 8/15/13 / 6 gal Glyphosate / 12
9/30/13 – 10/01/13 / 1.5 gal Imazapyr / 12
9/30/13 – 10/01/13 / 6 gal Glyphosate / 12
RESULTS
Table 3 contains data from 2010 to 2013. This data allows for the analysis of the impact of the eradication of the phragmites. The dates are in various colors in correspondence to the dates on which treatment was done. The dates in the color blue indicate data obtained prior to the treatments, while the red dates indicate data obtained after the treatment. Dates in the color green represent data collected during the treatment. And dates in the color black represent time in between treatments.
Table 2 A Table of The Water Quality of Cove River (2010-2013)
Furthermore, among the data obtained was the progress of the growth of the experimental plants. The heights of the plants are shown recorded in table 3. Figure 4 is a visual presentation of the recorded data in table 3. The dashes represent plants that were washed out and destroyed. This data only is only from 2013 because new plants were planted.
Table 3 The Heights of Plants Over Time
Plant 1 / Plant 2 / Plant 3 / Plant 4 / Plant 5 / Plant 6 / Plant 7 / Plant 8 / Plant 9 / Plant 10 / Plant 11 / Plant 121 Nov 13 / 49 / 46 / 107 / 78 / 50 / 88.5 / 93 / 49 / 101 / 25 / 70.5 / 105.5
18 Nov 13 / 54 / 52 / 129 / 83.2 / 50 / -- / -- / 54 / 109 / -- / 73.5 / 109
6 Dec 13 / 35 / -- / 130 / -- / 51 / -- / -- / 75 / 113 / -- / 59 / 109
Fig. 3 The Heights of Plants Over Time
Cove River will be studied for the remainder of 2014 into 2015 in order to have sufficient data to determine ultimate significance of the results presented here. However, so far, this data has proven the initial hypothesis correct.
DISCUSSION AND CONCLUSIONS
In the ongoing research of the Cove River in West Haven, the water quality and habitat are observed in order to determine whether the eradication of the invasive, phragmites Australis, has positively affected the environment. The data is beginning to prove the hypothesis correct, although more data is necessary to make a complete conclusion.
Analysis of Water Quality
The variables being tested are phosphate levels, nitrate levels, pH, dissolved oxygen levels, and temperature.
Nitrates are naturally occurring chemical compounds containing atoms of nitrogen and oxygen critical to the continuation of life on earth because they are the means by which plants obtain nitrogen (“Just”). Normal levels of nitrates are okay in rivers and do not have a direct effect on the aquatic life or environment. However, excess levels of nitrates in water can “create conditions that make it difficult for aquatic insects or fish to survive” (“Nitrates,” 2014). Therefore, based on this information, the levels of nitrates at Cove River, which were observed to be very low, neither harms nor helps the environment. It is seen in table 2 in fact, that the nitrate levels following treatment were significantly lower than the nitrate levels in between treatment. This indicates that treatment does impact the nitrate level and that ongoing treatment will work to maintain nitrate levels healthy and low. An excess level of nitrates means an excess of algae and plants. From this data, it can be inferred that there is not much algae or plant growth within the water at Cove River after treatment. Thus, this implies that treatment also works to remove excess algae.
Phosphorous aids in the growth of biological organisms and occurs naturally in bodies of water in the form of phosphate (“Just”). Like nitrate, phosphate controls how much plant growth can occur. The level of phosphate also determines how clean or dirty water is. Lower phosphates indicate cleaner water; clean water has phosphate levels usually between .01 and .03 mg/l (“Phosphorous”). Levels of phosphatehigher than .3 mg/l indicate pollution from fertilizer, sewage, or industrial waste (“Phosphorous”). The phosphate level of the Cove River indicates that the water is classified as “waste water” (“Phosphorous”). It can be implied that the phosphate levels are high due to the eradication of the phragmites Australis, which may have polluted the water, considering the phosphate levels are highest after treatment.
The amount of dissolved oxygen in an area is very important in determining habitat quality because without oxygen, many living organisms within this ecosystem would perish (“Eyes,” 2013). If the dissolved oxygen level of an environment drops below 5 mg/l, then it is indicated that the organisms within the water become stressed (“Eyes,” 2013). An example of this occurred on October 21, 2011, on which the dissolved oxygen level dropped to 2.4 mg/L. The level was again low on November 18 of 2013. These low levels make it very hard for the sensitive organisms to survive. Though those levels were low, they were quite normal on November 1 and December 6 of 2013, indicating that the organisms were not as strained. As can be seen, dissolved oxygen levels fluctuate greatly. This indicates that the presence of phragmites and its removal do not really impact the dissolved oxygen levels.
The pH levels of the Cove River are normal. According to table 3 obtained from 1996, the pH levels of the Cove River (West Haven High) were very similar, indicating that the removal of the invasive did not alter the pH of the water (Sharp, Cook, & Tolderlund, 1996). The pH fluctuates around 7, which means that the water is very neutral.
Table 4 pH Results of Cove River (1996)
Analysis of Plant Growth
The data of the plant growth poses for multiple theories. As can be seen, many of the plants did not survive the third visit. This is because of the harsh winter endured in 2013. The rain, snow, and other acts of nature destroyed number of the plants. New plants will replace the destroyed ones so that data can continue to be obtained. Prior to the damage caused by the weather, according to the data, the plants were in act growing. For instance, plant 3 grew from 107 cm the first visit, to 130 cm on the third visit. While this plant and others grew, plants like plant 1, deteriorated. It is theorized that intense winds during the winter cut down the plant. This is one of the reasons why the research will continue throughout the year. This theory can only be proven with extensive research during different seasons. However, based on the data retrieved so far, it can be concluded that the Cove River is habitable.
Conclusions
An overall analysis of the environment of the Cove River thus far indicates that the eradication of the phragmites has benefited the environment. pH levels remain neutral, which is respectable for aquatic life and plant growth. The dissolved oxygen levels determined that the organisms of Cove River tend to endure stress but are mostly in a healthy habitat. Furthermore, the low nitrate levels indicate that not much algae resides in the river, while the high phosphate levels determine that the water is polluted. Despite the pollution of the water however, it is a habitable environment due to the eradication of the phragmites.
This ongoing research will obtain further data from Cove River in order to formulate a complete thesis and conclusion. In all, from the preliminary data, it can be seen that the eradication of the phragmites Australis has benefited Cove River.
REFERENCES
(2003). Haplotype/ Haplotypes. Retrieved from
Capotosto, P.Wolfe, R.(2007). Controlling phragmites Australis in Connecticut’s fresh and salt-water marshes. Wetland Habitat amd Mosquito Management Program.
Eyes on the Bay (2013).Eyes on the bay. Retrieved from
Gucker, C. L. (2008). Phragmites Australis. Fire Effects Information System.Retrieved from