Plants and Absorption of Substances Research

In this experiment, inexperienced algae condition of growth was once determined. The absorption of, low nitrogen, high nitrogen, low phosphorous, high phosphorous, low acid rain and excessive acid rain was determined. Test tubes were organized and different quantities of the acid rain, phosphorous and nitrogen used to be added and later placed on a plant increase condition designated place for two weeks. The absorbency of each test tube was once determined by use of a spectrometer. The effects of the experiment were recorded as follows: The absorption of low nitrogen via the green algae is less than the absorbency of excessive nitrogen by the green algae, The suggest absorbency of high phosphorous is higher than the common absorbency of low phosphorous, and The average absorbency of high acid rain is greater than the absorbency of low acid rain. In conclusion, algae require levels of nitrogen for its growth, it also requires elevated levels of phosphorous for its growth and requires the low level of acid rain since it requires a low pH level.

INTRODUCTION

For green algae to grow, it requires nutrients, water, and carbon source. The most important nutrients are phosphorous, nitrogen, iron and Sulphur. Phosphorous makes up about 1% of the total biomass that algae require and about 0.005% to sustain its growth (Vance cp, 2001). Excess phosphorous level results to high growth of algae. Nitrogen is not limited and is a limiting micro nutrient when it comes to its growth. Algae require nitrogen to act as a fixer of nitrates and similar molecules to act as a nutrient source (Boonchai $ Gyutae, 2015). Excess nitrogen since its not limited in the air is very conducive for the growth of algae. In excess, it increases the level of growth of algae. Sulfur is a major factor and is needed for electron transport and also protein synthesis and lipid metabolism. The pH conditions for growth of algae are between 9 and 11. This is almost to alkaline water so low acid rain can deteriorate its growth or the conditions can affect its growth. High acid rain too can affect its growth by denaturing the enzymes (William $ jack, 1995). More than acid rain also causes the decrease in aquatic organisms.
The objectives of this experiment was to become familiar with the conditions necessary for fostering growth of algae, understand that excess nitrogen and phosphorous act as pollutants, understand that excess growth can lead to increased growth of algae, understand that acid rain is a pollutant and can lead to decrease in aquatic organisms, understand that absorbency can be an indirect measure of growth of algae and also understand that a number of algae growing under different conditions can be measured using a spectrophotometer. In this experiment the hypothesis included algae growth will increase as the concentration of nitrogen pollution increases, algae growth will increase as the concentration of phosphorus increases, and algae growth will decrease as the concentration of acid rain pollution decreases.

METHODS

Each table prepared the test tubes below: control, low nitrogen, high nitrogen, low phosphorous, high phosphorous, low acid rain and high acid rain. Seven test tubes were obtained each 25mland labelled using labelling tape as follows control (c),low nitrogen(LN) ,high nitrogen(HN),low phosphorous(LP),high phosphorous(HP),low acid rain(LAR) and high acid rain(HAR).Water, algae, and pollutants were added according to the table below

Tube Algae Pollutant Water
Control 2.5ml 0ml 12.5ml
Low
(N,P,AR) 2.5ml 1,5ml 11.0ml
HIGH
(N.P.AR) 2.5ml 3.0ml 9.5ml
A plug made of cotton wool in a square piece of gauze (5cm by 5cm) was inserted into the mouth no each test tube. The instructor directed that the test tube is put in a designated area which is a plant growth light where they will remain for two weeks. A clean up was done that involved wiping spilled material using a tissue paper and returning all materials to the appropriate place.

The seven test tubes prepared two weeks ago by the group were obtained. The absorbency of each test tube was determined using the following procedures: the spectrometer was calibrated and zero using distilled water, a cuvette was filled with distilled water, and its exterior wiped dry using a tissue paper, the cuvette was placed in the spectrometer, the wavelength was set at 450nm, the absorbency of the distilled water was read from the absorbency scale.
The absorbency of each treatment test tube was determined as follows: the contents of the test tube was thoroughly mixed by moving the base of the test tube in 10cm circle on the table for approximately 10 secs, the contents of the test tube was poured into a clean cuvette until it was a quarter full with the sample and its exterior was wiped dry using a tissue paper, the Corvette was placed on the spectrometer and the wavelength was set at 450nm,the absorbency of the sample was read from the absorbency scale and recorded in Table 9.1 of the data sheet, the contents of the Corvette was returned back to the sample test tube from which it came from, the cuvette was rinsed with distilled water. The steps were repeated until the absorbency of each test tube was determined. The data was, copied on the black board for transparency. A clean up was done which involved emptying contents of all test tube into waste containers, washing all test tubes, all spilled material was wiped using a paper towel and all materials were returned to original areas.

RESULTS

Table 9. Absorbency (of 450nm) of control verses pollutant treatment by concentration and lab group
Absorbency at 450nm

Lab group Control Low
Nitrogen Low phosphorous High phosphorous Low acid rain High acid rain
1 0.271 0.13 0.96 0.2 0.1710 0.064 0
2 0.243 0.58 0.083 0.035 0.260 0.010 0.11
3 0.041 0.049 0.143 0.260 0.040 0.018 0.060
4 0.003 0.167 0.327 0.018 0.234 0.003 0.19
5 0.022 0.238 0.01 0.135 0.153 0.034 0.019
6 0.03 0.42 0.031 0.253 0.114 -0.13 -0.014
Mean 0.598 0.0892 0.156 0.1282 0.186 0.0114 0.015

DISCUSSION

Algae growth was expected to increase with an increase of nitrogen pollution. The absorption of low nitrogen by the green algae is lower than the absorbency of high nitrogen by the green algae. Algae require high levels of nitrogen since nitrogen acts as a fixer of nitrates and similar molecules to act as nutrient source (Boonchai & Gyutae, 2015) .The absorption of nitrogen by the algae in the experiment is as expected.
The algae growth was expected to increase as the concentration of phosphorous pollution increased. The mean absorbency of high phosphorous is higher than the mean absorbency of low phosphorous. This was probably an effect since algae. Phosphorous makes up about 1% of the total biomass that algae requires and about 0.005% to sustain its growth (Vance cp 2001).according to the experiment it is not as expected as only low levels of phosphorous is needed for growth of algae. The result of the experiment could be that way as in the experiment other factors for example temperature was not considered.
Algae growth was expected to decrease as the concentration of acid rain decreased. The mean absorbency of high acid rain is higher than the absorbency of low acid rain. Algae requires a pH of 7-9 which is a high level of acid (William& jack 1955).The results of absorption of high acid rain are not as expected since excess acid rain can cause the decrease in growth of algae. This can be caused by the experiment not considering other factors for growth of algae for example temperature which resulted to the green algae replacing it.
Sources of errors: errors from inaccurate reading of the spectrometer because of resolution and parallax, error from failure to consider other factors conducive for growth of algae
In conclusion, algae require levels of nitrogen for its growth, it also requires high levels of phosphorous for its growth and also requires the low level of acid rain since it requires a low pH level.

REFERENCES

Boonchai, R., & Seo, G. (2015). Microalgae membrane photobioreactor for further removal of nitrogen and phosphorus from secondary sewage effluent. Korean Journal of Chemical Engineering, 32(10), 2047-2052.
Kratz, William A., and Jack Myers. \\\"Nutrition and growth of several blue-green algae.\\\" American Journal of Botany (1955): 282-287.
Vance, C. P. (2001). Symbiotic nitrogen fixation and phosphorus acquisition. Plant nutrition in a world of declining renewable resources. Plant Physiology, 127(2), 390-397.