Acid Rain, Draft 4

This topic submitted by Megan Smith, Alex White, Joe Riffe, David Marimon, Ariel Flowers (megjs_5@hotmail.com, arielflowers@hotmail.com) at 4:56 PM on 10/15/02. Additions were last made on Wednesday, December 10, 2008. Section: Negron-Ortiz

Natural Systems 1 Fall, 2002 -Western Program-Miami University

Megan Smith, David Marimon, Joe Riffe, Ariel Flowers and Alex White

Introduction:
We are interested in studying the effects of acid rain on winter rye, blue bush beans and radishes in both seedlings and 3-week old sprouts. We are mimicking the effects of acid rain in our experiment and comparing it to the effects of acid rain in our natural environment. In order to test the effects on these plants, we are watering the plants with HCl for different pH concentrations.

We hypothesize that our control group, the plants being watered with tap water will be the only specimens to survive. While we were brainstorming for ideas, we visited the greenhouse and decided that we wanted to do a project that involved plants. After much thought, we decided on a test that would demonstrate natural effects of acid occurrences in nature. That is when we came up with an idea of the acid rain test.

In this experiment we plan to learn: 1) about the effects of acid rain on plants in general, 2) how different levels of pH will affect different species, 3) what is the lowest pH concentration a plant can tolerate. Inversely, we will learn the long term affects that acid rain has on our environment and how that can endanger and possibly extinct some plant species. We also want to determine which plants are more adaptable to changes in the environment, and at which stages in their life cycle they are more adaptable, such as tested by our seedlings and our sprouts.

Relevance of Research Question:

Rain is naturally somewhat acidic. However, organisms and ecosystems have adapted to this slight acidity. The problem lies in the increased acidity caused by human activity such as the burning of fossil fuels. . Acid rain damages areas with shallow soil more that other areas, because it takes needed nutrients out of the soil. It also can damage the foliage of trees and delay their growth. The acidity is measured on a ph scale, 1 to 14, seven being normal drinking water. Each degree away from 7 is ten times as acidic or basic as the previous level. In New York acidity in rain have been measured up to 2.6. (U.S. Environment Protection Agency)

Acid rain (acid deposition) is a fairly large term that describes the ways in which acid comes from the atmosphere. Dry deposition is acidic particles and gases in the atmosphere; 50% of which fall back to the earth as dry deposition. These particles can be washed from trees and cars during rainstorms. The runoff water adds these acids to the acid rain making it even more acidic that the rain- water. It has been proven that sulfur dioxide and nitrogen oxides are the main causes of acid rain. (U.S. Environment Protection Agency)

Acid rain is more likely to weaken trees by damaging their leaves rather than killing them directly. By damaging their leaves, they trees cannot receive as many nutrients, thus delaying their growth, or making them more susceptible to toxic substances. Trees high in the mountains are more likely to be damaged because of the higher amounts of acid clouds and fog (which is more acidic than rainfall). Crops are not as likely to be harmed by acid rain because fertilizers added to the soil and replace the nutrients that have been washed away. (Kohno, Y., Matsuki, R., Nomera, S., Mitsunari, K., Nakao, M., 2001)

Norway Spruce buds were teasted at four years of age and subjected to acid rain simulation. Ph concentrations of 2.9 and 3.9 were sprayed on the shoot systems for a period of two years. Conclusions prove a decrease in leaf primordial and a flatness of the apical meristem. These changes in the buds did not occur at all in the control group, providing that it was the effect of the acid rain which caused the destruction of the buds. (Albrechtova J., Opatina J., Soukupova J., Svobodova H., 2002)

One group of scholars tested the effects of acid droplets of Sulfuric acid, with a pH ranging from 1.0 to 4.0 on the leaf surfaces of a sensitive plant, the Yoshino cherry, and a more insensitive plant, the Oshima cherry. Although the spot where the droplet was placed disappeared in both plants after 6 hours, the acidic water had spread over the surface area, lowering the Ph of the entire leaf only slightly. The group concluded that the leaves could neutralize the surface acid, possibly by ion exchange, in a relatively short amount of time. (Kohno Y., Matsuki R., Nomera S., Mitsunari K., Nakao M., 2001)

This article documents a study done for four years on the functional consequences of stressing microarthropod by exposing them to components of polluted rain. These components include nitric acid sulfuric acid, ammonium sulfate and other elements. The compared plots sprayed with the polluted rainwater compared to plots sprayed with distilled water. They found that the abundance of five key stone species was drastically affected by the polluted waters. (Heneghan L, Bolger T)

Another group of scholars tested the effects of anion composition of simulated acid rain, with a PH concentration of 3.0 on saline soils. The control group was watered with a Ph concentration of 5.7. Samples of soil studied, collected from Korea and Japan, showed that the soilÕs organic matter actually decreased as well as the presence of ammonia nitrogen. The amount of nutrients changed quite a bit with the increase in the amount of simulated acid rain. (Cho JY., Nishiyama M., Matsumoto S., 2002)

It is not only acid rain that is threatening our natural ecosystems and forests but acid fog and acid vapor. These forms of acid affect the natural ecosystems on three levels. The foliage of plants is affected which reduces a plants ability to withstand cold while also inhibiting plan germination and reproduction. Acid rain brains the soil of many valuable nutrients, while increasing the levels of more carcinogenic elements in the soil like aluminum, which inhibits the intake of water and minerals. The acid rain also affects the local water supply, slowly poisoning the land and the ecosystem population of trees. (Baird, S., 1993)

The effects of increased nitrogen inputs have become more severe. The severity depends on the conditions of, the buffering capacity, soil nutrients status and the nitrogen immobilization rate. The most important effects of nitrogen deposition are accumulation of nitrogenous compounds, soil-mediated effects of acidification as well as an increased susceptibility to stress factors. The plants that are more resistant to this acid are more likely to become dominant Ð although this is only at the expense of the plants only typical of intermediate pH. (Bobrink, R., Hornung, M., Roefloes, J., 1998)

Following the methods of other authors, we have decided to test hardy plants because they will represent the majority of plants in our environment. The three different types of plants we are testing all exhibit different types of foliages, which will become pertinent in relating our findings and results to the ecosystem. We chose to test the groups of plants at both the seedling level and the 3-week old sprout level. The older plants are already well established with bigger root systems and are somewhat better off at defending themselves from the effects of the environment. We want to compare them with seedlings.

Materials and methods:
We are investigating two different groups. Our first group is of 3-week old plant composed of 8 pots of winter rye plants, 8 radish plants, and 8 blue bush bean plants, each pot containing one plant. Our second group is composed of 8 pots of winter rye plants, 8 radish plants and 8 blue bush bean plants, each pot containing one plant. One plant of each species, and each group will be watered with a pH concentration of 1, one with a pH concentration of 3, another with a pH concentration of 5, and the last with tap water. pH levels will be regulated with HCL.

Our project is statistically sound because we have a control group of 12 plants, sprouts and seedlings, and a logical hypothesis, which should be easy to test. Also, we are using a large sample of plants so as not to have a biased outcome. In order to prevent our test from being biased, we will measure an equal amount of water/HCL to water the plants with every other day. We will keep consistent with our watering, constantly making visual observations, such as measuring height as well as recording the pH level in the soil.

We will have the class help us with our experiment by doing various things. They will be asked to measure the pH concentration of the soil, using pH strips. Also, they will make visual observations recording findings such as plant height, color change, wilting, and any decay.

After their observations, we will have the class water the plants with the varying acidic water. The class will not process data. We will do that later as a group at the end of our experiment. Data that we will be recording on a regular basis include the pH, and height of the plants. Our research will show whether these two factors are closely correlated.

Important materials that we are using include the plants we are testing: winter rye seeds, blue bush bean seeds, and radish seeds, HCL to control pH levels, water, soil and 12 pots. We will keep our plants in the greenhouse connected to Boyd Hall, and consistently water them every- other day. We will make observations each visit.

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Albrechtova, J., Opatrina, J., Soukupova, J., Svobodova, H., : 2002, Anatomical and histochemical changes of Norway spruce buds induced by simulated acid rain 45: 77-83.

Bobrink, R., Hornung, M., Roefloes, J.,: 1998, The effects of airborne nitrogen pollutants on species diversity in natural and semi-natural European vegetation 86: 717-738

Cho, JY., Nishiyama, M., Matsumoto, S.,: 2002, Soil Science and Plant nutrition 48: 461-468.

Heneghan L, Bolger T, Effect of components of acid rain on the contribution of soil microarthropods to ecosystem function. Journal of Applied Ecology 1996, 1329-1344

Baird, S.,:1993, Energy Educators of Ontario, Energy Fact Sheet.
http://www.iclei.org/efacts/acidrain.htm

Kohno, Y., Matsuki, R., Nomera, S., Mitsunari, K. and Nakao, M.: 2001, Neutralization of Acid Droplets on Plant Leaf Surfaces 130: 977-982.

U.S Environment Protection Agency
http://www.epa.gov/airmarkets/acidrain/effects/forests.html#trees
http://www.epa.gov/airmarkets/acidrain/effects/forests.html#plants

U.S Environment Protection Agency
http://www.epa.gov/airmarkets/acidrain/index.html#what

http://www.ec.gc.ca/acidrain/acidforest.html

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