Effect of Akulikuli Plant on Water Quality (2012)

An Investigation on the Effects of Akulikuli Sesuvium portulacastrum on the Quality of Ala Wai Water (Hawaii, 2009.) Kai Kane Mr Kay/Mrs Shimamoto May 22, 2012 Abstract: Our experiment is designed to test the effect that Akulikuli plants, a native, hardy plant, have on the Ala Wai water quality Environmentalists and researchers are aiming to use such plants like Akulikuli to clean up, or phytoremediate, the rancid waters of the Ala Wai Already, Akulikuli plants have been launched on rafts in hopes that their roots will remove harmful chemicals from the water and restore a measure of cleanliness to the canal We wanted to see the exact effects that Akulikuli could have on water so in our experiment we set up five tubs Three contained Ala Wai water and the other two had fresh water from a hose In one fresh water tub we put three Akulikuli plants One Ala Wai water tub had three Akulikuli plants and one had six Akulikuli plants The tubs that did not have Akulikuli plants were used as control The tubs were set in an area with sun for the plants but where it would not rain Over a month and two days we took four readings The data we collected, which cannot be considered entirely accurate, demonstrate that while Akulikuli would not change dissolved oxygen percentage or the total amount of dissolved solids in the Ala Wai, Akulikuli would certainly decrease salinity, neutralize pH, and increase dissolved nitrogen levels Phytoremediation is a viable method of improving water quality, but the limited effectiveness may not be worth the high cost necessary to clean the Ala Wai Question: Can the presence and growth of Akulikuli Sesuvium portulacastrum improve the quality of contaminated Ala Wai water as measured in terms of dissolved oxygen, pH, nitrate levels, and salinity when the system is monitored over an extended period of time? (Hawaii, 2009) Introduction and Research: Long ago, the Ala Wai was created to rid the swampy wetlands in Waikiki of the mosquitos and make the land suitable for industrial and agricultural development; the early settlers of Hawaii wished to make Waikiki adequate for growth by draining the natural swamps giving rise to the canal Displacing the natural waterway from the mountains to the ocean has had drastic effects on the ecology and homeostasis of the Ala Wai There has been a buildup of sediment, phosphorous, nitrogen, heavy metals, and street water runoff that have contributed to the muck and scum of the Ala Wai we know today The Ala Wai has now become polluted and is in dire need of phytoremediation to rejuvenate the waterway to homeostatic balance As settlers developed the land they often destroyed environmental niches in the ecosystem disrupting the balance of nature, known as homeostasis With creation of the Ala Wai, immigrants devastated the means of plants to absorb nitrogen and phosphorous in the natural waterway This plethora of excess nutrients provided an oasis for algal blooms and microorganisms According to the Health Department, the average nitrogen concentrations in the Ala Wai canal are six times the accepted state standards, and phosphorous levels are double the acceptable levels (Vorsino, 2007) This phenomenon of excess nutrients and sediment accumulation is known as eutrophication and can cause severe environmental effects: increased phytoplankton biomass, decreased clarity, reduced levels of light at depth, and a significant decrease in dissolved oxygen levels (Mack, 2012) This in turn can turn a body of water from a recreational lake to a green muck wasteland Such has happened to the Ala Wai in the past years transforming a waterway where local kids would swim and play to a mucky wasteland with the stench of decay that can be smelled by tourists in Waikiki In order to rejuvenate the Ala Wai to its former clean state, an indigenous Hawaiian plant has been selected to take on the job Akulikuli, more commonly known as sea purslane, is a hardy and salt tolerant plant that acts to fill the ecological niche eliminated by the swamps, which were drained many years ago (Hawaii, 2009) Now, through the Akulikuli’s process of phytoremediation, environmental biologists hope to improve the water quality of the Ala Wai Phytoremediation is the use of vegetation to extract biological contaminants from the ground or water Phytoremediation can remove metals from water, and it is also very effective in remediating soil and organic compounds (Florio, Rembijas) It is a cost-efficient method of cleaning up pollution, estimated to range from sixty cents to six dollars for every 1000 gallons of water, with a safer environmental impact because all extraction tools would be organic (NASC) Some other benefits of Phytoremediation are that the selected sites are more aesthetically pleasing and low maintenance after being set up Phytoremediation is not an uncommon method of treating polluted soil or water, but Akulikuli would be particularly welcome in Hawaii because it is an indigenous plant Projects have been underway since 2005 with help from a 500 thousand dollar grant Morris Takushi, a director of Natural Systems, received permits from the U.S Coast Guard and U.S Army Corps of Engineers to introduce the Akulikuli plant into the Ala Wai A total of forty to eighty 3,000 foot rafts were placed in the canal as "floating phytoremediation platforms" according to project manager Chad Durkin of Natural Systems Inc in May 2005 (Nakaso, 2005) There are downsides to phytoremediation, however Efficiency is dependent upon the survival and health of the active plants There is a considerable amount of time involved in setting up a phytoremediation system, more than other remediation technologies Extracted toxins can also become products in biological magnification if the plants are consumed, releasing the pollutants directly into an organism (NASC) Phytoremediation is also not as effective for sites with high contaminant concentrations and it is slower at improving water or soil quality than conventional methods Finally, Phytoremediation does not work through winter therefore it is seasonally effective (Florio, Rembijas) However, this would not be a problem in the eversummer season of Hawaii By placing the Akulikuli in the Ala Wai on floating beds, the roots of the plant drop down to depths of about three to five feet and are surrounded by fishnets to keep larger fish from eating away the roots The plants, roots, bacteria, including mycorrhizae, a symbiotic fungal organism, and microorganisms create a floating ecosystem that acts to absorb nutrients including nitrogen, in the form of nitrates, and phosphorous from the water By using Akulikuli to fill the niche and essentially choking out the algal blooms, the Ala Wai can be remediated back to its natural state This clean state would allow for safe fishing, canoe paddling, and other recreational activities once abundant and enjoyed by Waikiki locals David Penn, a water-quality coordinator for the Department of Health, said, "We know the system does function to remove pollutants, but we don't know what the overall capacity of the system would be on a large scale" (Vorsino, 2006) The dearth of interest and data on the effects of the Akulikuli plant on water-quality has forced the project to shut down, leaving the problem to the next generation, as many problems in our world have remained Since the early immigrants of Hawaii settled the swamps of Waikiki, they have understood and appreciated the importance of the natural flow of water from the mountains to the ocean The avarice of developers of Waikiki neglected the ‘aina and its importance in the native culture Today, the Ala Wai remains a reminder of the neglect bestowed on our island and way of life The indigenous Hawaiian plant, Akulikuli has shown hopes in the lab to phytoremediate the Ala Wai water Clearly, the Ala Wai is in desperate need of phytoremediation by Akulikuli, but this task will be left up to future generations with hopes seen by Mr Kay and the University of Hawaii A previous AP Biology group, Team Hyacinth, studied the effects of Akulikuli specifically on the turbidity over a period of three days Our investigation spanned one month and identified any changes in the percentage of dissolved oxygen, pH, concentration of nitrates, and salinity An improvement in water quality was indicated by an increase in dissolved oxygen, a neutral pH, increased nitrates, and a lowered salinity In this environment, fish and plants would receive better living conditions; therefore a combination of any of the above improvements would constitute a successful phytoremediation process Materials and Methods: In order to conduct this experiment, collect four styrofoam bins, metal wire mesh, wood, tap water, buckets, Ala Wai water samples, YSI Sonde, scissors, paper, pencils, and computer Collect all available materials and begin by setting up the four styrofoam bins along with a control bucket for tap water and label them as such: “1:Ala Wai Water w/o Akulikuli , 2:Tap Water w/o Akulikuli, 3:Ala Wai Water and Akulikuli Plant 4:Tap Water and Akulikuli Plant, 5: Ala Wai Water and 2xAkulikuli Plant.” Water samples will be taken from the Ala Wai off the dock and taken back to the set up bins While some team members are getting water, cut circles for the potted Akulikuli plants Three circles need to be cut into the styrofoam for bins # and Six holes need to be cut for bin #5 (One of our bins needed to be reinforced with wire mesh and wood so it would not break under the weight of the plants.) Fill each bin with the same volume of water; volumes vary due to bin size, so that the water submerges the bottom of each pot, insuring that the Akulikuli roots can reach the water Take measurements of pH, nitrates, dissolved oxygen and salinity levels and record them on a data table using the YSI Sonde Date: Bin 1: Ala Wai w/o Akuli Bin 2: Tap Water w/o Akuli Bin 3: Ala Wai Akuli Bin 4: Tap Water Akuli Bin 5: Ala Wai 2xAkuli Salinity (PPT) Percent Dissolved Oxygen (%) pH Nitrates (g/L) Place three potted Akulikuli plants in bins and and place six potted Akulikuli plants in bin #5 6 Allow the plants and water to interact for an extended period of time, approximately one month and take YSI Sonde measurements as often as desired to have enough data to analyze Taking Data: Remove the lids of each of the bins so the YSI Sonde probe can be completely submerged Run the YSI Sonde for approximately 30 seconds, as it takes readings every seconds This will insure a more accurate reading Mark the time and the order of bins on a piece of paper so data can be collected off the computer after all readings are taken After taking all readings make sure to place all plants and lids into their respective bin Data: See attached documnet with project pictures-Discussion: On December 7, 2011 the YSCI was not properly calibrated for all readings so data collected on this day is most likely invalid When initially obtaining the water, we may have stirred up sediment that was not present in other water containers Akulikuli was effective in desalinating the Ala Wai water In the 1x Akulikuli tubs, salinity dropped by over 74.3% Doubling the amount of Akulikuli yielded a drop in salinity of over 90.3% Increasing the amount of Akulikuli thus decreases the salt content of water Such evidence supports the argument that the Akulikuli is responsible for significantly desalinating the Ala Wai water At the beginning of our investigation we found that both Ala Wai water and our tap water were too basic for living organisms In order for aquatic plants like Akulikuli to survive and thrive in optimum conditions, the pH of the water should fall between 6.5 and 8.0 Any value less than 6.5 would make the water too acidic for the Akulikuli and thus less hospitable, and any value greater than 8.0 would saturate the Akulikuli with excess nutrients Our results show that in all of our tubs containing Akulikuli plants, the pH level in these tubs decreased However, the pH levels within these tubs moved into the optimum pH range In the tub containing Akulikuli in fresh water, the pH level of the water went down slightly from about 8.45 to about 7.95 This represented a move from a pH level outside the optimum range to one within the optimum range In the tub containing Ala Wai water and x1 Akulikuli the pH level went down from 8.1 to 7.3 In the tub containing Ala Wai water and x2 Akulikuli the pH level went down more significantly from 8.1 to 7.1 This increased rate was expected since more Akulikuli should accelerate the process of pH change; however we did not anticipate this change to proceed quicker than it did In both the tubs Ala Wai water and Akulikuli, the pH of the water was just out of the optimum range, however, the decrease in pH that was observed in both tubs, brought the pH levels of these tubs further within the optimum pH ranges Both our Ala Wai control and our freshwater control showed slight decreases in pH levels overtime when they should have generally exhibited no change in pH, but Overall, the pH changes/moves toward optimum pH levels that we observed in all of our tubs containing Akulikuli plants are important in maximizing the effectiveness of the Akulikuli in the phytoremediation process This will help improve water quality especially in polluted waters like the Ala Wai Not only plants like fairly neutral pHs, but marine fish also prefer this range of pH Since Akulikuli moves the pH of the water towards neutral, both fish and aquatic plants will benefit from the lowering of pH Our data showed that the amount of nitrate (NO3) present in the water of all of the tubs containing Akulikuli increased over time This occurred because the mycorrhizae on the plants were able to fix nitrogen at a rate that was greater than the rate at which the plants were using the nitrogen High nitrate rates are beneficial for the survival of plants like the Akulikuli and consequently the function of these plants This allows them to act more efficiently in improving water quality At the start Ala Wai water contained more nitrates than tap water By the end of the investigation, the fresh water that had contained Akulikuli plants had a higher nitrate level than the Ala Wai control water The Ala Wai water that had six Akulikuli plants almost tripled the initial concentration of nitrates Akulikuli does not greatly affect the percent of dissolved oxygen within a fluid Although plants produce oxygen from their leaves, this oxygen does not go into the water, it goes into the air Since oxygen is not produced in the roots, almost no oxygen will be dissolved into the water Only submerged plants and photosynthesizing protists such as algae will increase the amount of dissolved oxygen For future experiments, we would design a system with two large tanks 4' X 3' X3' which would house the Akulikuli system These tanks would be separate however one would act as a holding tank for Ala Wai water and sediment as well as aquatic organisms like fish and crabs The other tank would have a floating hydroponic tray with the Akulikuli plants They would create a more stable micro-ecosystem Both tanks would have bubblers at the bottom to stir up the sediment and maintain high dissolved oxygen levels to support aquatic animal life A pump from the holding tank would move water to the Akulikuli tank and a bottom tube would connect the two tanks together This would stimulate a flow of water present in the Ala Wai ecosystem This set up would be more controlled and evaporation would be cut down in a lab environment The large amount of water would make it easier to take readings and simulate the effects in a larger body of water more so than out styrofoam tubs Conclusion:  Proper calibration is needed for more accurate readings  Our data regarding turbidity was inconclusive  Dissolved nitrogen was increased due to nitrogen-fixing mycorrhizae  Akulikuli actively decrease the salinity of brackish water  Total dissolved solids were not removed by the Akulikuli  Akulikuli actively neutralize pH of water  More accurate research must be done on the effects of Akulikuli on water quality  Our setup was good and accounted for many environmental factors by including a control setup However, no small setup could be expected to account for all environmental factors, such as the large variety of organic life  Further research may be done regarding whether Akulikuli would actively alter the pH of a strongly basic or strongly acidic environment Future experimentation must be conducted on a larger scale in order to investigate the extent to which Akulikuli affects water quality Works Cited: Florio, Nathan and Rembijas, Hayes “Phytoremediation of Soil and Organic Rensselaer Polytechnic Institute Jan 10, 2012 Accessed April 27, 2012 Compounds” Gonser, James "Plants at root of pollution solution." Honolulu Advertiser April 21, 2005 Accessed May 1, 2012 Hawaii, University of "Sesuvium portulacastrum." Native Plants Hawaii 2009 Accessed May 1, 2012 Leone, Diana "Green is clean for Ala Wai." Star Bulletin May 8, 2005 Accessed May 1, 2012 Mack, Jeremey "Eutrophication." Lake Scientist 2012 Accessed May 1, 2012 Nakaso, Dan "'Akulikuli cleansing of the Ala Wai under way." Honolulu Advertiser May 8, 2005 Accessed May 1, 2012 Nottingham Arabidopsis Stock Centre "What Is Phytoremediation?" European Arabidopsis Stock Centre Nottingham Arabidopsis Stock Centre Sept 27, 2011 Accessed Jan 23,2012 Vorsino, Mary "No funding for floating Waikiki canal plants." Honolulu Advertiser Oct 6, 2007 Accessed May 1, 2012 ... styrofoam bins along with a control bucket for tap water and label them as such: “1:Ala Wai Water w/o Akulikuli , 2:Tap Water w/o Akulikuli, 3:Ala Wai Water and Akulikuli Plant 4:Tap Water and Akulikuli. .. of brackish water  Total dissolved solids were not removed by the Akulikuli  Akulikuli actively neutralize pH of water  More accurate research must be done on the effects of Akulikuli on water. .. pollutants, but we don't know what the overall capacity of the system would be on a large scale" (Vorsino, 2006) The dearth of interest and data on the effects of the Akulikuli plant on water- quality has