Through a series of experiments to explore the effects of human activity on other living organisms, this study is aimed to answer the following question of to what extent do acid rain and air pollutants affect the height and total leaf area of peanut plants (Arachis hypogaea).
The experiments documented the mean growth in height as well as leaf area of peanut plants that were exposed to varying amounts of aluminum, nitrogen, and phosphorus. The plants received twelve hours of direct sunlight, were kept at 72 degrees Fahrenheit, and were kept in soils with aluminum, nitrogen, and phosphorus. The aluminum was equal to a pH of 2.5, 3.5, and 4.5. The levels of nitrogen, which were distributed into nine different pots, three of the same amount per three pots, were 50 mL, 75 mL, and 100 mL, and the phosphorus amounts were 8lb A/6” soil (L), 20lb A/6” soil (M), and 64lb A/6” soil (H). The phosphorus levels were determined using a soil N-P-K kit and water from a local stream.
Positive correlations were found between the height of the plants and the leaf area. As the plants increased in height, the leaves increased in area. Furthermore, as the amount (pH) of aluminum sulfate decreases, the height and area decreased. The increasing amounts of phosphorus promoted growth, as did nitrogen. However, too much nitrogen caused the plants to die. These results indicated that low pH levels and high nitrogen levels cause harm to peanut plants, and that phosphorus promotes growth. In conclusion, acid rain and pollutants high in nitrogen inhibit growth, while pollutants high in potassium encourage growth.
I am concerned about the current levels of pollution and its impact on living organisms. There is growing research that suggests that acid rain and air pollutants are dangerously affecting the growth of terrestrial and aquatic life in industrialized areas (Ojima, Kittel, & Rosswall, 316). Although most of the information found, regarding pollutants, focused on forests and lakes, concern for the effect of pollution on crop productivity and growth remain. However, because pollution is too broad to be examined in sufficient detail within the extended essay, the topic was narrowed down to an investigation consisting of a series of experiments and analyses of a single organisms’ developmental response to variations in three elements frequently found in pollutants and in acid rain: aluminum, nitrogen, and phosphorus.
I chose to experiment with peanut plants (Genus: Arachis, Species: hypogaea [Encyclopedia Britannica, 2011]), because they are “one of [the] top five cash crops” of my home state, Georgia (“Peanuts | UGA Cooperative Extension”). Georgia leads in the production of peanuts, in the United States, producing 1.64 billion pounds in 2008 alone, and providing more than forty-five percent of the U.S. peanut crop each year. (“Peanuts| UGA Cooperative Extension”). According to the USDA Census of Agriculture, Georgia had 2,762 peanut...