Background Information: So the Dissolved Oxygen lab’s objectives are to test the different methods used to find levels of Dissolved Oxygen, and to see how some variables affect the amounts of D.O. Together, the Winkler method and the Vernier probe were used to find the measurements we’re looking for. Besides measuring dissolved oxygen (that’s pretty much a no-brainer) we’re also looking for organisms in the water samples, the amount of carbon dioxide, nitrates, temperature, and pH, all of which are important in the health of an ecosystem. Most of the results are found using a Vernier probe, but the Winkler method was used to test what effects temperature and light has on dissolved oxygen. An ecosystem is incredibly fragile, which is why a change in carbon dioxide, pH, dissolved oxygen, and temperature can have a devastating effect on it. Since many of the factors are linked in some way (dissolved oxygen has an inverse relationship with carbon dioxide. The more carbon dioxide, the more acidic the water is) if one changes, others will be affected as well. From measuring and monitoring pH, temperature, etc. biologists will be able to learn what conditions certain species prefer, how to co-exist with aquatic ecosystems, and how to preserve the environment. Sources of Samples: The samples were taken from three water sources; the Sandy Hook Beach on Sandy Hook Bay (Beach Water), Delaware-Raritan Canal (Canal Water), and Tommy’s Pond (Pond Water) in Metuchen, New Jersey. Each environment experiences many different variables. For instance, Sandy Hook (Beach Water) is a coastal environment, and is constantly windy and full of waves. It is a natural extension of the peninsula roughly 2000 acres; a “barrier spit” which has coast on either side of it. This water in the bay is often cold, but it is teeming with fish and other aquatic creatures which attract fishers and other businesses. The bay is in a ideal location, perfect for boats to pull in and out of; consequently, there is much human and boating activity. The bay supports populated cities, and small coastal towns alike. Our second location, the Delaware-Raritan Canal (Canal Water) is a fresh water environment. The canal is a man-made body of water leading from the Delaware River to the Raritan River. Different sections of the canal are stagnant, while others flow freely. Human activity occurs on and near the canal, and some of its length runs along roads and railroad tracks. It doesn’t support tons of fish or organism life except in the spring and summer months, although fish can be found all year round. Interestingly enough, the canal has several historic structures alongside it, is 70 miles long, and runs through several nature parks. The last body of water where we obtained our samples was Tommy Park’s Pond (Pond Water). In Metuchen, New Jersey. The pond is a relatively small body of fresh, unmoving water that is located near a relatively small town. Town events occur near the pond, and small boating events occurs on it. It is surrounded by houses and road, and has no visible organisms to mention. Likewise, the pond has algae blooms that occur from runoff and other chemicals leeching into the water from nearby, causing its water to become a murky brown-green color.   Sandy Hook Beach (strip of land on right)    Barley Straw Bales being placed in Tommy Pond to reverse harmful chemical levels. The main objectives of the Dissolved Oxygen lab were to compare results from the two different methods that were used – the Vernier probe and the Winkler method. In addition to the main methods, factors that affect dissolved oxygen levels were also tested: the amount of light and the temperature of the water samples. These factors and methods were tested on water samples from three different environments: Sandy Hook, Tommy’s Pond in Metuchen, NJ, and the Delaware and Raritan Canal. Ultimately, the main variables tested were the effects of light and temperature on levels of Dissolved Oxygen. Hypothesis: If the water samples have a lower temperature, than the levels of dissolved oxygen will be higher. More specifically, if the canal water sample has a temperature of 20ºC, the dissolved oxygen levels will be lower than the beach water, which has a temperature of 0ºC, temperature being the overriding factor against salinity. Ultimately, if the temperature is higher for the canal water, the dissolved oxygen levels will be low, just as the beach water contains salt, which will also lower the levels of the dissolved oxygen, so that the levels of D.O are ultimately low. Since photosynthesis needs light, if there is more light, than there will be more dissolved oxygen due to photosynthesis. How do I get Gross Productivity; Net Productivity; Respiration?
----------------------------------------------------------------------------------------------------- Relating Class/Ideal Dissolved Oxygen Charts  |
| Class's Disolved Oxygen Gross VS. Net Productivity Data Table (Light) |
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| Class's Dissolved Oxygen Data Table (Temperature) |
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| Example/Ideal Dissolved Oxygen Data Table (Temperature) |
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| Example/Ideal Dissolved Oxygen Data Table (Light) |
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| Class's Vernier Probe Data Table --------------------------------------------------------------------------------------------------- Is there a relationship between Dissolved Oxygen levels and the types of plants, animals, or organisms in the water? Although there were no organisms observed in our water samples, one can easily imagine that the more dissolved oxygen, the better. Most vertebrates in an aquatic ecosystem need Dissolved Oxygen levels of 8-15 to survive. 3.5-6 can be stressful for some organisms, and anything less than 3 can be fatal, especially for salmon and other large fish. Areas with low dissolved oxygen levels may have dead fish and organisms in the water, due to the lack of dissolved oxygen. Ultimately, animals, plants, and other organisms need higher rather than lower levels of dissolved oxygen to survive and thrive. What about the levels of carbon dioxide in the water? Does this reading correspond with your dissolved oxygen levels? Since carbon dioxide and oxygen have an inverse relationship – meaning that one goes up while the other goes down – high amounts of carbon dioxide mean low amounts of oxygen. If you take a gander at fig. 3, for example, you will see that the levels of dissolved oxygen and the levels of gross productivity for carbon are very, very different. High carbon dioxide levels will also make the pH of the water more acidic. When an organism dies and begins to decompose, it continues to use oxygen and give off carbon dioxide. Interestingly enough, the levels of carbon dioxide vary between time of the day and seasons, meaning that dissolved oxygen levels also vary accordingly to these factors. Because ecosystems manage to survive, clearly a balance is established between carbon dioxide and oxygen. Human effects that increase oxygen or carbon dioxide interfere with an aquatic ecosystem that may result in the demise of organisms and the ultimate downfall of the ecosystem itself. Do you think your water source is a good environment for organisms to survive based on pH levels? Why or why not? The pH levels can not only be used to see how acidic or basic the water is, but to see if the levels of carbon dioxide are very high as well – more carbon dioxide means a lower pH. Some organisms prefer more acidic water, so one can find a wide variety of species depending on the pH. The ideal level of pH is 7-8, and most of our results for pond, beach, and canal water ranged from 6.62-6.92. One could hold the slightly acidic water samples responsible for the lack of organisms. Slightly more basic levels of pH would be ideal for organisms in the water samples we experimented with. Is there a relationship between Nitrate and Phosphate levels and observed algae or plant life in the water? Although we didn’t measure phosphate levels in the water samples, a healthy ecosystem should have below 0.1 mg/L. Nitrate levels should be below 1mg/L. If there are too many nutrients, an algal bloom can occur resulting in eutrophication. The only water sample that had nitrates measured was the pond water, which had the maximum amount of 1 mg/L. All in all, the pond water seemed to be the best quality, even if no organisms were observed. Is there a relationship between Turbidity level and the type and variety of organisms observed in the water? Even though no organisms were observed in our numerous water samples, one can draw the conclusion that you would observe fewer organisms due to the fact that visibility would decrease, which can affect individuals that rely on their visual abilities, such as salmon. Vegetation also is negatively affected by turbidity, as the transmission of light is greatly reduced. Where there is no vegetation, chances are, there will not be many organisms, either. How does your dissolved oxygen reading from the Vernier probe compare with your dissolved oxygen readings as done with the Winkler method? What is the value of utilizing several methods to obtain information about an ecosystem? Interestingly enough, the values obtained from the Winkler method and the results from the Vernier method are drastically different. The Vernier probe, for example, revealed that the dissolved oxygen levels of the sample were 3.5 mg/L. In sharp contrast, the results from the Winkler method were 1 mg/L for canal water and 0.6 for beach. By using several methods, one can compare their results and efficiency for each method. In this case, the Vernier probe was probably more accurate, as there was no change concerning the number of drops (some groups may have put in more than others, and some groups may have counted differently.) Because there was no real way the Vernier probe could go wrong, it is probably the more accurate as well as convenient method to use.  Various Vernier Probes  Winkler Method Did any of your results indicate poor or good water quality? How do you know? As far as quality goes, the water tested was pretty poor quality. Not only was their no sign of life whatsoever, but with the exception of temperature, all factors tested were NOT ideal for organisms. For every sample, the water was too acidic. The only sample with ideal dissolved oxygen levels was the pond water. In addition to acidity and low dissolved oxygen, there was too much carbon dioxide and too much turbidity. Although organisms can exist with such poor water quality, it is not ideal and the organisms are most likely stressed. In what ways can your data determine the quality of health of an ecosystem? How can you use this information to monitor and maintain the health of natural environments? To monitor the quality of health for an ecosystem, one can easily juxtapose the ideal levels for numerous factors and the results from a water sample. Since humans can negatively impact factors such as pH, carbon dioxide, temperature, etc. it is important to monitor ecosystems. By knowing about changes in dissolved oxygen, turbidity, and so on, one can fix the problem and have the ecosystem return to stability. Conclusions Perhaps the most shocking thing in this lab is how different our results were from the ideals. All three water sources had little to no dissolved oxygen, including the beach water sample which was exposed to currents, crashing waves, and variables that increase dissolved oxygen in water. The other results were easily recorded with the Vernier probe. Our levels in nitrogen and DO were nowhere near ideal, and the water in all samples held no life. This data shows that the conditions in the areas where the samples were taken from are able to hold little to no life. There may have been flaws with the Winkler Method, but the results show no water organisms or resources to support life. This may or may not be true because the sources of the samples supposedly are able to hold bigger organisms and whole ecosystems. Businesses and companies also thrive on the edges of the samples locations. Still, it’s not surprising that there was little dissolved oxygen in the water. The Delaware-Raritan Canal has stagnate water in some places, Sandy Hook beach experienced a very hot summer which actually killed some of its native fish, and Tommy’s Pond has succumbed to algae blooms that threaten any life nearby. These results may be awry, but it may be likely that they are true. Fisheries, fishers, Conservationists, the EPA, and water treatment plants all rely on this data. The difference in dissolved oxygen and other levels, could pose environmental, economic, and health effects for people and creatures nearby, not to mention in the water. The difference between ideal conditions and a failing ecosystem are easy to see, and preventable if monitored and protected. Outreach Plan The New Jersey Water Resources Research Institute, New Jersey Devision of Water Quality, the Fishing Industry, and Boating Industry would probably be interested in the data collected, and other information like it for their businesses to survive. Most of these industries use data like this, already record it, or need it. The New Jersey Water Monitoring and Standards directed by the Environmental Protection agency does just this. Composed of many associations and organizations this group develops methods to reverse dangerous water levels, and focus on more local and small-scale water sources. By reversing runoff, and litter problems in creeks, lakes, and estuaries they provide help for water systems all over New Jersey. Delaware River Basin’s Atlantic States Marine Fisheries Commission (ASMFC) in New Jersey also provided examples of dissolved oxygen levels breaking ideal conditions, and affecting certain populations of fish species especially one species called “shad”. Similarly, Rutgers College keeps a freshwater, and estuary monitoring program which teaches students about the matter, Rutgers College is currently rebuilding wetland environments. In the end, it seems that many organizations are already taking steps to reverse issues of eutrophication and denitrification caused by oxygen depletion and excess nutrients. Conservation Plan The plan we propose to help maintain local ecosystems using our information would be to set up data tables of water sources open to the public. We could use our past data as an example of water that that lack nutrients and dissolved oxygen. Using both the Winkler and Vernier Probe methods we could record dissolved oxygen, nitrogen, pH, and temperature levels in water. This data is essential for checking, the ideal levels of various factors in aquatic ecosystems. We would look for habitats nearby, and test for ideal environmental conditions all around as well as monitor the ecosystems and how they thrive. By recording this data, and sharing the charts with others whom have tested such levels we can compare levels in ecosystems that may or may not need conservation help. Once we learn which ecosystems are thriving, we can figure out what human or natural variables may be causing other environments to have uncharacteristic or harmful levels compared to the prospering ones. This experiment allows us to figure out if runoff, litter, nearby human activity, or acid rain are harming these areas specifically. Once we know exactly where the problem is, we can take simple measures to reverse eutrophication and dissolved oxygen loss. Also, by presenting this data online, we would encourage trustworthy sources to go out, and do the same in their nearby lakes, ponds, and oceans. In conclusion, this effort would be made visible to the public and scientific community for free use, like in Metuchen, New Jersey, where locals are taking simple steps to reverse eutrophication and algae blooms in Tommy Pond with carefully placed balls of barley straw which bring harmfully high levels of chemicals down. Monitoring this for them would be helpful in many ways, and prove the usefulness of dissolved oxygen research and its use in conservation efforts that need to be developed. Citations: "NJDEP Water Monitoring & Standards - Volunteer Monitoring - Chemical Monitoring." The Official Web Site for The State of New Jersey. Web. 25 Sept. 2010. http://www.state.nj.us/dep/wms/bwqsa/vm/watershed_watch_members.html WATERSHED WATCH NETWORK COUNCIL MEMBERS. Retrieved September 25, 2010, from New Jersey Department of Environmental Protection: http://www.state.nj.us/dep/wms/bwqsa/vm/watershed_watch_members.html TOMMY’S POND BARLEY STRAW FACT SHEET. Retrieved September 25, 2010, from The Metuchen Environmental Commission: http://www.metuchennj.org/pond_barley_straw_fact_sheet.html Dissolved Oxygen. Retrieved September 25, 2010, from The Lower Fox River Watershed Monitoring Program: http://www.uwgb.edu/watershed/data/monitoring/oxygen.htm Bruckner, M. Z. (n.d.). The Winkler Method - Measuring Dissolved Oxygen. Retrieved September 25, 2010, from Montana State University: http://serc.carleton.edu/microbelife/research_methods/environ_sampling/oxygen.html EPA #910/9-91-001. (May, 1991) Monitoring Guidelines to Evaluate Effects of Forestry Activities on Streams in Pacific Northwest and Alaska. Retrieved from http://yosemite.epa.gov/R10/EXTAFF.NSF/webpage/Water+Pollution+Publications Bjornn & Reiser, edited by William R. Meehan. (1991). Influences of Forest and Rangeland Management on Salmonid Fishes and Their Habitats. Published by American Fisheries Society Publication. |
