ABSTRACT
Effect of human urine on the microbial and physicochemical properties of soil was investigated. The study was carried out in Michael Okpara university of Agriculture, Umudike Abia State where four soil samples contaminated with human urine (UrCs) were randomly collected within the University Campus from places noted for indiscriminate urination by students and analyzed for microbial and physicochemical properties. One uncontaminated agricultural soil (UnCs) sample was used as control. Mean counts of microorganisms in urine contaminated soil had a high count of (8.1 x 108) for total aerobic plate, Escherichia coli (6.6 x 107) and fungi (4.0 x 107) as compared with the control which had a lower count (3.6 x 108) for total aerobic plate, Escherchia coli (3.5 x 107) and fungi (3.3 x 107) respectively. Bacteria isolated included Staphylococcus (19.33%), Pseudomonas spp (15.13%), Klebsiella spp. (10.08%), Bacillus spp. (14.29%). The most frequently isolated fungi from UrCs included Aspergillus (44.64%), Mucor spp (17.86%), Candida (26.79%), Fusarium (10.71%). Physicochemical analysis of urine contaminated and uncontaminated soil samples showed that conductivity, moisture content, total organic carbon, nitrate ion, phosphate ion, sulphate ion and total nitrogen were higher in the urine contaminated soil than in uncontaminated soil while the pH of uncontaminated soil (4.5) was higher than the contaminated soil (4.1). The growth of maize with urine contaminated and uncontaminated soil revealed that urine enhanced the growth of maize as a result of increased microbial load and some essential elements such as Total Nitrogen, Organic carbon, Nitrate ion, Sulphate ion among others. There was significant difference between the control and the test groups for the fungi count (p>0.05) while there was no significant difference (p<0.05) between the control and test groups for E. coli count likewise for total aerobic plate count.
TABLE
OF CONTENTS
Title
page i
Certification ii
Dedication iii
Acknowledgements iv
Table
of Contents v
List
of Tables viii
List
of Plates ix
List
of Figures x
Abstract xi
CHAPTER ONE
1.0 INTRODUCTION 1
1.0.1 The soil microbiota 3
1.0.2 Storage of urine 5
1.0.3 Urine as a fertilizer 5
1.0.4 Merits of urine as a fertilizer 6
1.0.5 Demerits of urine as fertilizers 6
1.0.6 Effects
of human urine on the physicochemical properties of soil 7
1.1 Aims and objectives of the study 8
CHAPTER TWO
2.0 LITERATURE
REVIEW 9
2.1 Physical properties of soil 10
2.1.1 Soil pH 10
2.1.2 Soil colour 11
2.1.3 Soil texture 12
2.1.4 Soil structure 12
2.1.5 Porosity 13
2.1.6 Density 13
2.2 Chemical properties of soil 14
2.2.1 Soil Organic Matter 14
2.2.2 Soil Salinity 14
2.2.3 Soil temperature 15
2.2.4 Soil water 15
2.3 Physicochemical parameters of soil 16
2.4 Biological properties of soil 16
2.4.1 Soil Microflora 16
2.4.2 Soil Fauna 18
2.4.3 Actinobacteria 18
2.4.4 Fungi 18
2.4.5 Mycorrhizae 19
2.4.6 Earthworms, ants and termites 20
2.4.7 Soil Bacteria 20
2.5 Nitrogen cycle 21
2.5.1 Nitrification 21
2.5.2 Nitrogen fixation 22
2.5.3 Dentrification 22
2.6 Urine 22
2.6.1 Urine Contaminated Soil 23
2.6.2 Process of urine production 23
2.6.3 Composition of urine 24
2.6.4 Characteristics of Urine 24
2.6.4.1 Chemical analysis 24
2.6.4.2 Colour 24
2.6.4.3 Odour 25
2.6.4.4 Turbidty 26
2.6.4.5 pH 26
2.9.4.6 Density 26
2.9.4.7 Quantity/Volume 27
CHAPTER THREE
MATERIALS AND METHOD
3.1 Study area 28
3.2 Sample collection 28
3.3 Analysis of samples 29
3.3.1 Physicochemical analysis of soil 29
3.3.1.1 Sterilization method 29
3.3.2 Microbial Analysis 29
3.3.2.1 Sample inoculation 29
3.3.2.2 Quantitative estimation of bacterial and fungal
isolates 29
3.3.2.3 Colony purification 30
3.3.2.4 Identification of bacterial isolates 30
3.3.2.5 Gram Staining Reaction 30
3.3.2.6 Spore Staining Technique 30
3.3.2.7 Motility Test 31
3.3.3 Biochemical Test 31
3.3.3.1 Methyl Red and Voges – Proskauer (MRVP) 31
3.3.3.2 Methyl Red Test 31
3.3.3.3 Voges-Proskauer Test 32
3.3.3.4 Indole Production 32
3.3.3.5 Catalase 32
3.3.3.6 Coagulase 32
3.3.3.7 Citrate Test 33
3.3.3.8 Oxidase Test 33
3.3.4 Identification of Fungal Isolates 33
3.3.4.1 Wet preparation 33
3.3.4.2Colonial
Morphology 33
3.4 Calculation of percentage of occurrence 33
3.5 Statistical analysis 34
CHAPTER FOUR
RESULTS 35
CHAPTER FIVE
DISCUSSION, RECOMMENDATIONS AND CONCLUSION
5.1 Discussion 45
5.2 Conclusion 46
5.3 Recommendations 47
REFERENCES
APPENDIX
LIST
OF TABLES
Table Number Title Page Number
2.1: Different physicochemical
parameters of soil 16
2.2: Different Bacteria found in
the soil 21
4.1: Average
counts of Microbial Load of Urine Contaminated (UrCs) and uncontaminated (UnCs) Soil 37
4.2: Bacteria
isolated and the percentage occurrence 38
4.3: Fungi
isolated and their percentage occurrence 39
4.4a: Cell
morphology, gram stain reaction and biochemical characterization
of bacterial isolates
for urine contaminated soil 40
4.4b: Cell
morphology, gram stain reaction and biochemical characterization
of bacterial isolates
for uncontaminated soil (Control) 41
4.5: The colonial and cell
morphology of fungal isolates 42
4.6: Physicochemical
Analysis of UrCs and UnCs 43
4.7: The
Values of the Heights of the Grown Maize compared between UrCs and UnCs 44
LIST OF PLATES
Plate Title Page
Number
1:
Maize
grown with urine contaminated and uncontaminated soil 52
2:
Bacterial
growth on nutrient agar 53
3:
Fungal
growth of Sabouraud-Dextrose agar 54
LIST OF FIGURES
Figure Title Page Number
1: Graph of mean Count of
Microbial Load of UrCs and UnCs Soil 55
2: Graph of height against
days using urine contaminated and uncontaminated soil for the growth of
maize plant 55
CHAPTER
ONE
1.0 INTRODUCTION
The soil is a complex habitat, inhabited
by a large number of different organisms (Prescott et al., 2006). Among these, bacteria and fungi are the most
important because they are responsible for the decomposition of organic matter
an also make up the largest biomass in soil nitrogen, sulphur, phosphorus and
other cycles mediated by microbes. Despite soil being the habitats for the
majority of earth’s terrestrial species, far less attention has been paid to
understanding maintenance of soil biodiversity until recently as pointed out by
Wardle (2002). Now, there is a growing interest in the below ground
biodiversity, largely as a result of advances in techniques that enable more
ready characterization of these biological diversity (Blaxter and Floyol, 2003;
Young and Crawford, 2004) and also because of the increasing recognition among
eco-physiologists that soil biota play key roles in ecosystem functioning,
especially organic matter turnover, nutrient mineralization (Hooper et al., 2000; Warale, 2002; Heimsbergen et al., 2004; Warale et al., 2004; Bardgette et al., 2005) and material flow through
the ecosystem (Bardgette et al., 2005).
Healthy soil played a major role as habitat for various forms of living things
ranging from microflora, microfauna, mesofauna, macrofauna to megafauna. And
these group in turn by their activity help to maintain a healthy, fertile and
productive soil by breaking down organic wastes into bioavaliable nutrients
which aid plants germination and growth.
The
organic and inorganic matter in the soil determines the soil fertility and aid
the proliferation of various microflora that play vital roles in maintaining
the nutritional balance of the soil. The topsoil has the highest concentration
of organic matter and microorganisms and it is where most of the earth’s
biological soil activity occurs. Hence, earth depends on soil to a great extent
and as human population grows, its depth, season of the year, state of
cultivation, organic demand for food from crops increases thereby making soil
conservation crucial. A few of the consequences of human activity and
carelessness are deforestration, over development and pollution from man-made
chemical and human wastes (Joanbne et
al., 2008). Though much study on organic pollutions and their resultant
effect on the soil environment have been conducted, not much information are
available on the effect of urine on soil environment especially of human
origin. Human urine in itself is not toxic except when mixed with faeces in
septic tanks and have been used as fertilizer for over 6,000 years. Kaiser
stated that a lot of nitrogen in manure came from urea which is contained in
urine as such human urine is a rich source of organic fertilizer.
The scientific study of soil is called
Pedology. Soil is composed of both organic and inorganic matter, and is
essential for life on earth to exist. Soils are a composition of mineral
particles 45%, organic matter 5%, air 25% and water 25%, texture, structure,
density, porosity, consistency, temperature, colour and resistivity. Most of
these determine the aeration of the soil and the ability of water to infiltrate
and to be held in the soil. Soil texture is determined by the relative
proportion of the three kinds of soil particles called soil “separates” sand
silt and clay. Larger soil structures called “peds” are created from the
separates when iron oxides, carbonates, clay and silica with the organic
constituent humus coat particles and cause them to adhere into larger,
relatively stable secondary structures, soil density, particularly bulk
density, is a measure of soil compaction. Soil porosity consists of the part of
the soil volume occupied by gases and water. Soil consistency is the ability of
soil to stick together. Soil temperature and colour are self-defining.
Resistivity refers to the resistance to conduction of electric currents and
affects the rate of corrosion of metal and concrete structures. The properties
may vary through the depth of a soil profile an complexity of the soil “food
web” means any appraisal of soil function most necessarily take into account
interactions with the living communities that exist within the soil. We know
that soil organisms break down organic matter, making nutrients available for
uptake by plants and other organisms. The nutrients stored in the bodies of
soil organisms prevent nutrient loss by leaching. Microbial exudates act to
maintain soil structure, and earthworms are important in bio-turbation.
However, we find that we don’t understand critical aspects about how these
populations function and interact. The discovery of glomalin in 1995 indicates
that we lack the knowledge to correctly answer some of the most basic questions
about the biogeochemical cycle in soils. We have much work ahead to gain a
better understanding of how soil biological components affect us and the
biosphere. In balanced soil, plants grow in an active and a steady environment.
The mineral content of the soil and its heartiful structure are important for
their wellbeing, but it is the life in the earth that powers its cycles and
provides its fertility. Without the activities of soil organisms organic
materials would accumulate and litter the soil surface, and there would be no
food for plants.
1.0.1 The soil microbiota
v Megafauna:
size range – 20mm upward e.g. Moles, Rabbits and Rodents.
v Macrofauna:
size range – 2 to 20mm, e.g. Woodlice, Earthworms, Beetles, Centipedes, Slugs,
Snails, Ants and Harvestmen.
v Mesofauna:
size range – 100 micrometer to 2mm, e.g. Tardigrades, Mites and Springtails.
v Microfauna and microflora:
size range – 1 to 100 micrometers, e.g. Yeasts, bacteria (commonly Actinobacteria),
Fungi, Protozoa, Roundworms and Rotifiers.
Of these bacteria and fungi play key role
in maintaining a healthy soil; they act as decomposers that break down organic
materials.
Urine
is the pale yellow fluid produced by the kidney and it contains urea, uric
acid, minerals, chloride, nitrogen, sulphur, ammonia, copper, iron, phosphate,
sodium, potassium, manganese, carbolic acid, calcium salts, vitamins: A, B, C
and E; enzymes, hippuric acid, creatinine as well as lactose. Others sugars are
sometimes excreted in urine, if their concentration in the body becomes very
high. Urea is abundant in the urine of humans and other mammals (Drangert,
2000). Urine is a liquid waste product excreted by the kidney and eliminated
from the body in the process of urination. Urine is made up of 95% water and 5%
organic solutes and inorganic ions. The main organic solutes in urine are urea,
uric acid, creatinine, trace amount of enzymes, carbohydrates and fatty acids
meanwhile inorganic ions are sodium (Na+), Potassium (K+),
Chloride (Cl-), calcium (Ca2+), Magnesium (Mg2+),
ammonium (NH4+), Sulphate (SO42-)
and Phosphates (PO43-). The concentration of nutrients in
urine varies with sex, age, diet, drinking water consumption and region which
are the reasons for variation in reports from different researchers (Karak and
Bhattacharyya, 2011). Through urine accounts only for 1% of the domestic
wastewater by volume, it contains 80% nitrogen (N), 55% phosphorus (P) and 60%
Potassium (K), which are the major plant nutrients (Jonsson et al., 2000).
The
pH of the urine range between 4-8. The bladder and urinary tracts are usually
sterile. The urethra however may contain a few commensals and also the perineum
which can contaminate urine when it is being passed out. Some of these
commensals are Diphtheroids, Enterobacteria, Acinetobacter species and some
skin commensals such as gram positive Staphylococci, Micrococci and Gram-positive
Enterococci. Female urine may be passed out along with some normal flora of the
vagina (Cheesebrough, 2006). Proper disposal of human waste is important to
avoid pollution and minimize the possibility of spreading diseases. Some
possible effects of indiscriminate urination are that, it is disgusting,
damages property value, impacts the quality of life for the people that have to
live with the stench, and diseases
(Knuttson and Kiddlunggren, 2000; Hoglund et
al., 2002).
In Nigeria, urine deposition in public
places go unchecked and has become a menace, a close examination of such soil
macrocosm reveals patchiness of soil, obvious decolouration, pungent ammonical
smell. There is therefore the need to establish the effect of human urine
deposition on soil microflora.
1.0.2 Storage of urine
Storage
of urine allows its use where the nutrients are most needed. Further during the
storage period, chemical processes kill pathogens. In tropical climates, urine
should be stored for about three months before application. If storage is not
possible, then the fresh urine should only be applied to tall standing crops.
Examples of such crops are Banana, Plantain, Papaya, Oranges, Avocado and Mango
(Jorn et al., 2008).
1.0.3 Urine as a fertilizer
Chief
motive that urine is an applicable fertilizer is because the majority of the
highly obtainable nutrients in urine exist in the form that plants can use
without difficulty. 75% or 90% of the nitrogen in urine is in the form of urea,
which becomes primarily ammonium ions in a aqueous solution of near neutral pH.
This ammonium can be biochemically shifted to nitrate (NO3) in the
presence of oxygen (Kvarsnstorm et al., 2006).
Phosphorus is excreted as phosphate ions (Jonsson et al., 2004). The majority of potassium, sulphur, and most
minerals of are also present as free ions (Kvarnstrom et al., 2006). These nutrients are directly available to plants in
these forms without processing. As with these forms without processing; as with
chemical fertilizers, urine is therefore a dilution of fast acting plant
nutrients than can work quickly to nourish plants (Ryan, 2010).
1.0.4 Merits of urine as a fertilizer
There
are many reasons that urine works so well as fertilizer. Human urine contains
the majority of plant fertilizing nutrients (Esery et al., 2001). This high nutrient, low pathogen combination means
that urine can be used very easily and safely to increase the yields of food
crops. And to this the ease and low cost of separating urine in most developing
world sanitation systems and it is easy to see why the use of urine fertilizer
could mean very real benefits for farmers and families with small gardens
(Moustapha, 2013).
1) May
encourage income generation (Improved yield and productivity of plants)
2) Reduces
dependence on costly chemical fertilizers.
3) Low
risk of pathogen transmission.
4) Low
costs.
1.0.5 Demerits of urine as fertilizers
1.
Urine is heavy and difficult to transport.
2. Smell
may be offensive.
3. Labour
intensive.
4. Risk
of soil sanitization if the soil is prone to the accumulation of salts.
5. Social
acceptance may be low in some areas.
The
use of urine based fertilizer and consumption of crops fertilized with human
excreta in general is influenced by cultural perception, religious beliefs and
hygienic concerns. However, where the concept of recycling nutrients in human
excreta for agricultural purposes has been well comprehended, most farmers
prefer urine to faeces, the common argument being that the former is less
repulsive and much easier to handle (Duncker et al., 2007; world health organization, 2006). A survey conducted
for seven European countries by Lienert and Larsen (2010) showed that over 85%
of 900 respondents liked the idea of using urine as a fertilizer and about 70%
were willing to purchase food grown with it. In the developing countries most
excreta recycling projects have recorded success. This can be explained by the
fact the recycling of human excreta is not an entirely new concept (Muilegger et al., 2010).
1.0.6 Effects of human urine on the physicochemical
properties of soil
Human
urine had significantly (p<0.05) higher effect on total nitrogen, available
phosphorus, exchangeable Calcium and Magnesium when compared with control. The
significant improvements of total Nitrogen (N), available phosphorus and
exchangeable Ca and Mg indicate that urine could be used as a useful fertilizer
for soil treatment. Similarly, the general increase of chemical properties
suggests that urine treatment can act as a fertilizer by increasing soil
nutrients and as a result enhances soil fertility and productivity. These
findings are supported by the report of Adeoluwa and Suleiman (2012) that urine
treatment improved soil fertility. Improvement in soil nitrogen was reported by
Gutter et al. (2005) and Schonning
(2001) that urine had short term nitrogen release efficiency. This was further corroborated
by Adeoluwa and Cofle (2012) that urine treatment improved fertility and
general conditions of soil. The significant increase in some soil chemical
properties and general superior performance of human urine treatment indicates
that it has more potential than other sources of urine for soil treatment. This
observation had earlier been reported by Benge (2006) and supported by Adeoluwa
and Sulaiman (2012) that human urine was a useful fertilizer that improved soil
fertility. The most adverse impact of human urine on soil biota is lowered pH
and increased acidity which unleash a vicious cycle on soil biota persisting as
long as urine deposition continues unhindered the same spot. Urine contaminated
soil causes reduction in the microbial load than uncontaminated soil.
1.1 AIMS AND OBJECTIVES OF THE STUDY
1.
To determine the effect of human urine on
the soil microflora and physicochemical properties.
2.
To isolate bacterial specie found in
urine-fertilized soils.
3.
To enumerate fungal counts in urine-based
soil.
4.
To determine the effect of urine on the
growth rates of crops.
5.
To characterize microorganisms found in
urine soils.
Click “DOWNLOAD NOW” below to get the complete Projects
FOR QUICK HELP CHAT WITH US NOW!
+(234) 0814 780 1594
Login To Comment