THE EFFECTS OF PH AND SALINITY ON THE RESPIRATORY ACTIVITIES OF AFRICAN LUNG FISH .

THE EFFECTS OF PH AND SALINITY ON THE RESPIRATORY ACTIVITIES OF AFRICAN LUNG FISH .
 
Abstract
         This work – The Effects of PH and salinity on the Respiratory Activities of African Lungfish Protopterus annectens has been a very interesting and revealing experience.  With the completion of this work, we believe that human activities such as farming and mining have been exposed to contribute immensely to the acidification of natural waters of Nigeria as a result of chronic or acute episodes of low PH due to pollution.  It is also our belief that this work will initiate a renewed confidence in our Biologists to nurture and manage our environment. Results obtained during this exercise show that low and very high PHdue to pollution produces perhaps the most striking effects.  At Low PH, fishes show symptoms of respiratory distress as a result of the coagulation of mucus on the gills of fishes.  On the other hand, the effect is very much pronounced at high salinity values.  This is to say that fishes show increase in respiratory rate at salinities, which are closest to the osmotic content of their body fluids.  However, departure from normal concentration and composition of the internal medium causes metabolic disturbances and eventual death.
CHAPTER ONE
INTRODUCTION
1.1   Background of the Study
The Longman Pocket English Dictionary (2001) simply defined the term “EFFECTS” as a result A more, detailed description of the same word can be obtained according to the Oxford Advanced Learner’s Dictionary by Hormby (2001) as: A change that somebody or something causes in somebody or something else.  F.G and H.N Fowler (2002) defined “EFFECT” as: Result of Consequence of Action.  Suffice it to say that the term “EFFECTS” throws more light on the impression produced on a spectator or hearer it also seeks to bring about, accomplish or cause an event to occur.  The definitions stated above imply that the term “EFFECTS” can be used in different contexts such as:
(i)          To state what the facts of a situation are
(ii)        To start the production of intended results
(iii)       To show that you are giving the general meaning of what somebody has said or written rather than the exact words.
In this context, the term “EFFECTS” is used to show how something is made to happen.  In the topic sentence of this project environmental conditions expected to affect the respiratory activities of aquatic life-forms including the African lungfish.
         A critical analysis of the topic sentence reveals key words such as EFFECTS, PH, SALINITY and RESPIRATION.  With the word EFFECTS” already, fully discussed, we shall now proceed to discussing the other ones.
         This symbol PH according to Butani (2006) represents Pouvoir HYDROGENE in French.  But in English language it is a symbol or abbreviation for HYDROGEN POWER. The author opined that PHindicates relative concentration of Hydrogen ions in solution.  This means that express the acidity or alkalinity of a medium.  The instrument with which to determine the PH of solution/media is known as the PH meter.
         Ababio (2001) observed that the acidity of a solution can be measured by the extent to which the solution transfers protons to water molecules to produce Hydronium ions (H3O+). He also opined that the alkalinity of the same solution can be determined by the extent to which the solution removes proton from water.
         The PH of a solution can also be calculated from the amount of H3O+ (Hydronium ions) that is formed in water solutions of Acids or of OH (Hydroxyl ions) formed in water solution of bases.  Therefore, the value of PH equals the negative logarithm of the hydronium ion concentration.
         Mathematically: PH = -log [H3O+]
         The importance of PH cannot be over emphasized hence some of the importances are state below
i.            An acid medium is required for the digestion of foods in the stomach while an alkaline mediums is required for food digestion in the small intestine.
ii.          Body fluids must be maintained at correct PH values. Deviations from these values may indicate ill health.  The PH of a normal human blood is 7.4.
iii.        PH values are important in pharmacy, medicine water purification, sewage treatment and several industrial processes.
iv.         Most plants grow well in soils with a PH of 7 to 5.
Butani (2006) explained salinity as the measure of saltiness of a body of water.  In his words; salinity refers to the measure of salt content of sea water.  Hence, we can infer that salinity is the degree of saltiness of a water body.  Marine ecosystems have water containing a mixture of salts, which make up 3.5% of the mass of a quantity of sea water in his words. Miller and Harley (1996) identified the five (5) ecosystems including:
i.            Estuaries
ii.          Littoral zones
iii.        Benthic zones
iv.         Oceanic zones
v.           Coral reefs
Having dwelt so much on physical factors such as PH and salinity, it is about time we discuss the physiological process of respiration. Therefore the next paragraph deals exclusively on the process of Respiration especially in fishes. Respiration according to Emeka (2008) is the process through, which digested food, is broken down in the body for the release of Energy.  This is an oxidation process. Carbondioxide (O2) and water are releases as waste products.  The chemical equation representing this product is given below.
    C6H12O6 + 6O2   →     6CO2         + 6H2O      + Energy
   Glucose      Oxygen       Dioxide      Water     or 36 molecule
   Of ATP
Respiration in fishes involves sending air in and out of the body of the fish and chemical reaction in their body cells in which energy is released.  It involves both physical and chemical processes, which are called GASEOUS EXCHANGE or EXTERNAL RESPIRATION.  The chemical process is called FOOD OXIDATION or INTERNAL RESPIRATION.
         Miller and Harley (1996) explained that External respiration is the breathing in of air or oxygen into the respiratory organ.  This process is known as INSPIRATION.  This is immediately followed by the breathing out of carbon dioxide and water vapor into the atmosphere otherwise called EXPIRATION.
         They also opined that internal or tissue Respiration is the oxidation of food within the cell leading to the release of energy, carbon dioxide and water.  Hence, we deduce the main facts associated with respiration from the above mentioned definitions to be
i.            Consumption of oxygen
ii.          Oxidation of the stores food
iii.        Liberation of carbon dioxide and small quantity of water vapor
iv.         Release of energy by the breakdown of organic food materials.
Variables
         Hornby (2001) posited that a variable means something that often changes or likely to change.  Based on this definition, the noticeable keyword is “CHANGE”. Hence, when a phenomenon, conditions situation, quantity or number can vary or be varied they are known as variables.
         Variables can assume the values of constants as postulated by Abugu (2009) in his words: A variable is a symbol for example x, h B that can assume any prescribed set of values called constant.  Also considering the following mathematical expression
         y = mx + c
Where y, M and C are variables with the values of M and C changing or being able to be changed.  The value of y depends on the values of m and c.  Hence, y is a dependent variables while M and C are independent variables.
         A closer look at this project topic however suggests that the two independent variables are PH and SALINITY while the dependent variable is the EFFECTS.
         Acidification of natural waters as a result of low PH has been reported to cause fish deaths. This is as a result of respiration distress on the part of the fishes.  On the other hand aquatic organisms have been observed to vary in their degree of toleration to saline concentration.
1.2   Statement of Problems
i.            Limited availability of water supply within the college premises
ii.          The stoichiometry and volumetric analysis of the reagents used.
iii.        At what PH should the fish have optimum respiratory Activity?
iv.         What will the respiratory activity be like at PH values of four (4), six (6), eight (8) and nine (9)?
v.           At what salinity value should we expect an optimum respiratory Activity?
vi.         How do the fishes respire at salinity value of one part per thousand (1‰), five parts per thousand (5‰), ten parts per thousand (10‰) and fifteen parts per thousand (15‰)?
1.3   Objectives of Study
         This project work is aimed at successfully examining the effects of salinity and PH on the respiratory activities of the African lungfish (Protopterus annectens).
Protopterus annectens according to Miller and Harley (1996) is adapted to a habitat, which is similar to that in which the fish terrestrial vertebrates are thought to have evolved so that information about the effects of different environmental parameters of their respiratory activities may help to educate the manner in which the ancestral tetrads became able to colonize terrestrial habitat.
1.4   Scope of Study
         This work is based on observation deduced on the effects of varied values of PH and salinity of the aquatic environment on the respiratory activities of P. annectens.
1.5   Research Questions
i.            What are the mass volume relationships of the reagents used in this study?
ii.          At what PH value are we expected to have optimum Respiratory activities?
iii.        What PH value produces the most striking effect on the respiratory activities of the fish?
iv.         At what PH value are we expected to observe respiratory disturbance and distress the most?
v.           What salinity value produces the most striking effect on the respiratory activities of the fish?
vi.         Is there any relationship between the mass in grams (g) of the fishes and their respiratory Activities
1.6   Significance of Study
         This work – The effects of PH and salinity on the respiratory Activities of African lungfish, Protopterus annectens has been a very interesting and revealing exercise  with  human activities such as farming and mining have been exposed to have contributed immensely to the acidification of natural waters of Nigeria as a result of chronic or acute episodes of low PH due to pollution.  It is also our belief that this work will initiate renewed confidence in our Biologists to nurture and manage our natural environment.
1.7   Hypothesis
         Atkins and James (1998) reported that molarities of H3O+ and OH- vary over many orders of magnitude.  According to them, in some solutions, they may be as low as 10-14 mol L-1.
         Hence, PH = Log [H30+].
         They posited that the logarithm in the definition above is a common logarithm to the base 10.  They also opined that [H3O+] in the molarity of H3O+ ions, with the units of moles per litter indicated.  For example: The PH of pure water in which the molarity of [H3O+] ions is 1.0 x 10-7 mol 2-1 at 25OC is:
         PH = -Log (1.0 x 10-7) = 7.00.
         The negative sign in the definition of PH means that the higher the H3O+ molarity, the lower the PH.
         Miller and Harley (1996) observed that organisms that show tolerance to wide variations in the salt concentration are Euryhaline while others that show a narrow range of tolerance to varied salt concentration one therefore called stenohaline animals.