Part 3: Mountain Ecology : Bacteria

“The true biologist deals with life, with teeming, boisterous life, and Learns something from it,

Learns that the first rule of life is living. “

JOHN STEINBECK

To date we have written a dozen or more articles on the pro active role of microorganisms in

shaping the destiny of the NW Mountains. However, off late we have received hundreds of e-mail

requests from all over the globe, asking us to elaborate on the type of microorganisms carrying out

these functions. Armed With a back ground of Microbiology and Horticulture, we have made an

honest attempt to simplify the role of BACTERIA in NW Mountain ecology.

All living organisms are classified as either PROKARYOTIC (PRIMITIVE) or EUKARYOTIC

(Higher forms of life) based on their cellular structure. Bacteria and blue green algae are grouped

under prokaryotes and all other organisms are eukaryotes. Bacteria are unicellular microscopic or

single celled organisms widely distributed in nature. The greatest benefit in studying bacteria is that

it throws light on the evolution of simple cellular systems and the higher forms of life.

Microorganisms are categorized into six distinct groups.

BACTERIA

FUNGI

ACTINOMYCETES

ALGAE

PROTOZOA

VIRUSES

The primary purpose of writing this article is to help farmers worldwide in understanding the basic 

premise on which BACTERIA operate and the ways and means of carefully exploiting their

potential to maintain a perfect ecological balance within the farm.

The farm habitat provides a fertile ground generating a host of both macro and micro organisms.

The bacteria are the most dominant group of microorganisms in soils. The microscopic analysis of

NW Mountain soils shows that there is plenty of room at the bottom for the proliferation of different

types of microorganisms because of the rich humus and organic matter content. Among the different

groups, bacteria are capable of harvesting atmospheric nitrogen, solubilisation of rock phosphate

and in the transformations of various substrates resulting in periodic supply of available nutrients

for plant growth and development. However, farmers need to understand that the types of bacteria

and their numbers are governed by the soil type and cultivation practices like addition of chemical

manures, pesticides, poisons, type of tillage etc. In turn the activity of bacteria is influenced by the

availability of nutrients, both in organic and inorganic forms. Their numbers are very high in

mountain soils with large number of trees compared to open meadows. This is due to the shading

nature as well as greater root density and the abundant availability of soil organic matter. Due to the

high organic matter content of such soils, bacteria decompose the organic matter and in the process

acquire energy.

Bacterial cells are so very small that when you think of these fastidious and ubiquitous microbes,

you need to think small. They are measured in microns and the equivalent of one micron is: one by

thousandth of a millimeter. Hence one needs a fairly high powered microscope to observe these

minute wonders. However, they have a remarkable advantage because they have their strength in

numbers. The population of bacterial cells in soils is always great. Due to their rapid growth and

short generation time they can quickly act on various organic materials. In harsh environments

lacking oxygen the bacteria alone are responsible for almost all the biological and chemical

changes. Because of their very small size bacteria have a very high ratio of surface area to volume.

Also, since bacteria are single celled microorganisms they absorb their nutrients through their cell

membrane, there by exhibiting very high metabolic rates.

The earliest inhabitants of Planet Earth have undoubtedly been the microorganisms. From primitive

prokaryotic unicellular microorganisms, evolved the higher forms of life. Microorganisms have thus

been the earliest participants in shaping various life processes.Microorganisms have been largely

responsible in changing the primordial atmosphere resulting in the formation of gaseous oxygen

needed for plant growth. Fifteen million years of evolution has shaped the forest and today their

future is in our hands. Fundamentally, it has been an evolution of skills. The evolutionary ladder

points out to the pivotal role played by microorganisms in adapting to harsh environmental

conditions, formation of tripartite bonds, break down of complex polysaccharides into simpler

molecules and in the process providing the energy needs of the biotic community. It is in this

context that this article throws light on the role of microorganisms, starting with BACTERIA in

transforming the mountain landscape into an evergreen rich forest. Among the different

microorganisms, Bacteria are known to play a vital role in the distribution and supply of energy

needs of the entire mountain. Decomposition of almost all insoluble salts is mediated by one or the

other group of bacterial communities.

DISTRIBUTION AND FUNCTIONS OF BACTERIA

Bacteria are widely distributed along the length and breadth of the mountain. In short they are found

almost every where. Bacteria are single celled organisms and in spite of their simplicity are highly

efficient. Their numbers decline with depth of soil.

A majority of the farmers are unaware that the great majority of bacteria are beneficial and absolutely 

necessary to convert farm wastes, organic debris and other by products into energy rich compounds 

needed for plant growth and development. Plants and animals depend on the fertility status of the soil 

and this in turn is dependent on the activity of soil microorganisms. Plants cannot directly utilize 

organic compounds such as fatty acids, lipids, carbohydrates and proteins. Microorganisms are a vital

 link in the mineralization of organic constituents and provide nutrients in the available form for plant 

growth and development.

Bacterial cells can withstand long periods of drought due to the protective cover around the cell wall 

known as CAPSULE. The capsule is a slimy or a gelatinous material and encloses either one cell or a 

group of cells. At times the bacteria make use of the polysaccharides present in the capsule as a source 

of reserve food material. The capsule enables the bacteria to avoid predation by larger soil microbes 

and infection from viral strains. In addition to protection, capsules also play an important role in the 

attachment of bacterial cells to plant or rock surfaces and in the formation of biofilms.

Bacteria are morphologically grouped into three types. Cell structure is a key element in the

characterization of bacteria.

1. Cylindrical or Rod shaped commonly referred to as Bacilli. They are the most numerous.

Bacillus species are known to overcome extreme weather conditions by the formation of endospores

that function as part of the normal life cycle of the bacterium. These endospores are resistant to long

periods of drought and desiccation. With the on set of favourable conditions the spore germinates and

a new bacterial cell grows.

2. Communication between all life is essential in unfolding the various patterns of life. Without the

ability to communicate, life, including the simplest single celled organism, could not exist. Bacteria

have the capacity to analyse vibrations in the surroundings and accordingly react. Besides shape

and size certain rod shaped bacteria have thin hair like appendages on the outer cell wall known as

flagella, which can sense the external environment and constantly send out chemical signals to

reach out to other communities. Flagella are believed to be organs of locomotion.

The number and place of attachment vary. When a single flagellum is attached to one end of the rod

it is known as MONOTRICHOUS. If the flagella are attached singly at both ends it is known as

AMPHITRICHOUS ; If more than one flagellum or a bunch of them are attached to either one end

or both the ends it is known as LOPHOTRICHOUS and if the flagella are covered all over the cell

it is known as PERITRICHOUS.

3. Spherical or ellipsoidal bacteria are called cocci. Ellipsoidal bacteria occur in pairs and are

referred to as STREPTOCOCCI, when in four cells, arranged in a square they are known as

TETRADS; when in irregular clusters like a bunch of grapes they are called STAPHYLOCOCCI

and when arranged in a cubical form known as SARCINAE.

4. Spiral or helicoidal.

Winogradsky a leading soil microbiologist placed Soil bacteria into two broad divisions.

A.AUTOCHTHONOUS SPECIES:

These refer to the indigenous or native species. The population of these bacteria is always uniform and 

constant in mountain soils because their nutrition is dependent on the native soil organic matter. They 

multiply rapidly in the presence of large quantities of biomass, organic matter, humus, and other soil

amendments having a low C:N ratio.

They are pretty tough and resistant to varied agro climatic conditions. They participate in all 

biochemical functions of the community. The presence of these bacteria is fairly high and their numbers

are constant. The presence or absence of specific nutrients does not change their numbers significantly.

 B. ALLOCHTHONOUS SPECIES OR ZYMOGENOUS BACTERIA OR FERMENTATIVE:

Commonly referred to as the invaders. Their participation in biochemical functions is insignificant.

These bacteria are active fomenters and need nutrients which are quickly exhausted. They are

involved in a process in which organic matter is rapidly attacked in successive stages and made

available to the plants. At each stage of decomposition a specific group of organism is involved.

The bacterial numbers increase rapidly whenever furnished with the special nutrients (leaf litter,

biomass, compost) to which they are adapted. On exhaustion of these nutrients their numbers

decrease and return with the addition of nutrients. Hence, this group of bacteria requires an external

source of energy for their multiplication and growth. Bacteria in this group include the nitrogen

fixers, phosphorus solubilisers, nitrifiers, cellulose hydrolysing bacteria, sulphur oxidizer’s, spore

forming bacillus and non spore forming pseudomonas.

ENVIRONMENTAL FACTORS

Bacterial numbers, their density, type and composition is governed by the environmental Stimulus.

The important factors are listed:

1. AERATION :

Bacteria are further divided as

AEROBES: Require the presence of oxygen for growth and metabolic activity.

ANAEROBES: Bacteria which grow in the absence of oxygen.

FACULTATIVE ANAEROBES: Develop either in the presence or absence of oxygen.

AEROTOLERANT ANAEROBES: These bacteria grow under both aerobic and anaerobic condition

2. MOISTURE :

Aerobic bacteria are the main stay in most soils and the optimum level of moisture content for their 

activities is in the range of 50 to 75% of the soil's moisture holding capacity. Farm soils are inherently 

shaded by tree canopies as well as by the mixed co-growth brush. Hence they remain shaded most of 

the time. Also, a host of factors result in the availability of moisture throughout the year. Water makes 

up a major component of the microbial cell. Hence it is a key component for the functioning of the cell. 

The most common problem encountered in mountain soils is not the lack of moisture but the availability

of excess moisture which is detrimental for the growth and multiplication of bacteria. Excess moisture 

limits the supply of gaseous oxygen resulting in an anaerobic environment. Water logging brings about 

a decrease in the abundance of bacteria.

. TEMPERATURE:

Bacteria are highly sensitive to temperature fluctuations. Apart from growth and development,

temperature plays a vital role in the biochemical processes carried out by the bacterial cell.

MESOPHILES are the ones which grow well in the temperature range of 25 to 35 degree centigrade. 

These constitute the bulk of the soil bacteria. For most part of the year the temperature profile in the 

mountain falls in this range. Some scientists have further divided mesophiles as:

OIKOPHILIC; Organisms whose optimum temperature is around 20 degree centigrade.

SOMATOPHILIC; Organisms whose optimum temperature is about 37 degree centigrade.

PSYCHROPHYLES are bacteria that love cold and grow at temperatures below 20 degree centigrade.

THERMOPHILES are temperature loving bacteria and grow best in the temperature range of 45 to

65 degree centigrade. These bacteria are active in compost pits.

4. ORGANIC MATTER:

The population of bacteria is directly related to the organic matter content of the soil. Due to periodic 

leaf shedding and availability of huge quantities of carbonaceous materials on the floor of the forest, 

the bacterial numbers is the largest. Also the farmers incorporate green manures, compost and biomass 

from time to time which act as stimulants for the growth and proliferation of bacteria.

5. ACIDITY:

The optimum pH for the growth of bacteria is NEUTRAL pH. Farmers need to keep the hydrogen ion 

concentration of their soils close to neutral because in highly alkaline or highly acidic conditions the 

growth and multiplication of bacteria is inhibited. In general in heavy rainfall areas receiving 100 

inches and more it is advisable to apply lime or dolomite once every two years and in moderate rainfall 

regions, once every four years. This practice will not only increase the bacterial numbers but will also 

enable the plants and trees to take up inorganic nutrients in a more efficient way.

ACIDOPHILIC BACTERIA: Bacteria capable of growth in extremely low pH

ALKALOPHILIC BACTERIA: Bacteria capable of growth in extremely alkaline soils (p H 10.5)

HALOPHILIC BACTERIA: Bacteria capable of tolerating high salt concentrations.

XEROPHILIC BACTERIA: Bacteria capable of growth in dry habitats.

6. INORGANIC NUTRIENTS:

Application of fertilizers and chemicals greatly affects the bacterial population. Farmer's world

wide use ammonium fertilizers as the bulk of fertilizer application. Farmers do not realize that

ammonium fertilizers tend to lower the soil pH resulting in acidity due to the microbial oxidation of

ammonium to nitric acid. More than the effect of fertilizer, it is the acidity which suppresses the

bacterial population. This problem can be easily overcome by split applications spread out over a

two week period. More importantly, the application of fertilizer should be carried out when the soil

moisture is optimum. It is a proven fact that small amounts of inorganic fertilizers supply the needs

of the bacterial community in the form of inorganic nutrients.

7. FARM PRACTICES:

Farm practices also exert direct and indirect biological effects on the farm.

Periodic soil disturbance will affect the bacterial population. Addition of organic manures from time to

time and incorporating legumes into the soil with proper carbon nitrogen ratio accelerates the build up

of beneficial micro flora. However, if soil hardens up over a period of time, then it will have an adverse 

effect on the bacterial numbers.

NUTRITIONAL REQUIREMENTS OF BACTERIA:

MACRONUTRIENTS:

Carbohydrarates, Proteins, Lipids, Nucleic Acids. Carbon requirement is the greatest, followed by

nitrogen, phosphorus and sulphur. Potassium, sodium, calcium and magnesium are also required in

substantial quantities.

MICRONUTRIENTS:

Cobalt, iron, zinc, copper, molybdenum, manganese.

Certain bacteria require specific organic compounds that they are unable to synthesize from simple

compounds. Hence they require GROWTH FACTORS classified into one of the following groups.

AMINO ACIDS

PURINES & PYRIMIDINES

VITAMINS.

The dominant groups of bacteria are the heterotrophs but a few genera have photo chromatic

pigments enabling them to have photoautotrophic nutrition.

Two main classes of bacteria are:

the HETEROTROPHS OR CHEMOORGANOTROPHIC: Bacteria which require preformed

an organic nutrient which serves as a source of energy and carbon.

AUTOTROPHIC OR LITHOTROPHIC: Bacteria which obtain their energy from sunlight or

by the oxidation of inorganic compounds and their carbon by the assimilation of carbon dioxide.

Autotrophs are further classified as: PHOTOAUTOTROPHS OR PHOTOLITHOTROPHS;

where energy is derived from sunlight and CHEMOAUTOTROPHS OR CHEMOLITHOTROPHS which 

obtain their energy from the oxidation of inorganic materials.

SPECIALISED BACTERIAL CELLS:

ENDOSPORES:

Bacterial communities have developed their own specialized skills to survive the hardships of nature. At 

times it involves a constant battle where it is not only the survival of the fittest but survival by way of 

forming alliances with other biotic communities. It involves constant signal exchange between 

predators and prey, struggles for dominance, defence of territories and many ways to simply survive by 

the production of spores and endospores which are tolerant to adverse weather conditions.

These structures are resistant to heat, desiccation, high salt concentrations, cold, osmosis and 

chemicals, compared to the vegetative cells producing them. Endospores are bodies produced within 

the cells of a considerable number of bacterial species. Sporulation confers protection to the cell 

whenever the occasion arises. Because of their low rate of metabolism , endospores can survive for a 

number of years without a source of nutrients. However, when favourable conditions appear, 

endospores begin to germinate within a few minutes to form a new vegetative cell.

MOST COMMONLY ENCOUNTERED SOIL BACTERIA:

Belong to the following genera Aerobacter, Myxobacteria, Bacillus, Pseudomonas, Flavobacterium, 

Arthrobacter, Achromobacter, Clostridium, Corynebacterium, Mycobacterium, Sarcina, Myxococcus, 

Archangium, Chondrococcus, Cytophaga, Sporocytophaga, Polyangium.

CHEMICAL COMPOSITION OF THE BACTERIAL CELL ON DRY WEIGHT BASIS :

The major constituent is water to the extent of 90 %.  The ash content varies.

CARBON 45-55% NITROGEN 8-15%.

The ash from bacteria may contain:

PHOSPHORUS 10-50%, POTASSIUM 4-25%, SODIUM 10- 35%, MAGNESIUM 0.1-10%,

SILICA 0.5-7.7%, CALCIUM 0.3-14%, CHLORINE 1-44%, and trace amounts of iron.

These variations are due to the different bacterial species on the floor of the mountain.

ISOLATION:

We have had the rare opportunity of isolating thousands of species of soil bacteria during our research 

studies. Our study included soils from various agro climatic regions of NW America.

Our results had far reaching consequences. We were able to prove that soils with neutral pH harboured

 the maximum load of nitrogen fixers and phosphate solubilizers. Different soil types had different 

species of bacteria but most of them were beneficial and acted as important links in various soil 

transformations.

Shade grown MOUNTAIN FARMS have sustained many generations of farmers because of their 

resilience in overcoming all odds. The secret behind this success is attributed to the microbial

inhabitants. Microorganisms cannot be seen by the naked eye, yet they constitute about one quarter of 

the biomass-the total weight of living organisms in the world. Animals and plants account for the 

remainder. In the strict sense, more than 98 % of what we describe as waste inside the farm is

valuable food for one or the other group of microorganisms. Bacteria recycle these wastes into power 

packed energy rich nutrients required for the survival of the medicine plants and its partners. Farmers 

have an erroneous concept of the role of bacteria in nature. They strongly feel that the majority of 

bacteria are disease producing. We would like to set the record straight and state that the vast majority

of bacteria are not only beneficial but are absolutely essential in building up a healthy farm. Yes, there 

are a very few bacterial species that are harmful but in a healthy ecosystem they rarely express 

themselves.

It is very important that the farmer understand the subtle role played by bacteria in the

transformation of major elements like nitrogen, sulfur and phosphorus, biodegradation, neutralizing

toxic wastes, bio-control agents and a host of other activities. Certain bacteria belonging to the

families Thiorhodaceae , Chlorobacteriaceae and Athiorhodaceae contain bacteriochlorophyll and

various carotenoids and are also capable of photosynthesis.

Bacterial interactions with the farm crops and the surrounding flora are known to improve plant

growth and productivity. The fertility of the soil is directly dependent on the activity of soil

microorganisms. The soil microorganisms mineralize insoluble and indiffusable organic

constituents and make them available to plants. The common denominator to assess a healthy soil is

the viable number of soil microorganisms.

he shade grown mountain ecosystem is unique in the true sense that it simultaneously achieves the 

goals of agricultural production in terms of pepper, citrus, vanilla, berries, and pine-nut production

on one hand and the conservation of biodiversity on the other hand.

Nothing would be wiser for the world's producing Nation's to follow in our footsteps and grow

crops under the canopy of trees, shrubs, mountain shadows. There in lies the path to sustainability.

In our humble opinion we strongly feel that only shared prosperity can make the future of this

planet secure. At UQD RESEARCH we work with ideas that might work or might not work. But in

the end analysis, these ideas are the core to the survival of PLANET EARTH.

Grendmaster-SWK, Chairman, University of Quantum Dynamics

REFERENCES:

Alexander ,M. 1974 . Microbial Ecology. New York. John Wiley and sons.

Alexander ,M. 1977 . Introduction to soil Microbiology. 2nd edition. New York. John Wiley and

sons.

Atlas, R.M. and R. Bartha. 1993. Microbial Ecology : Fundamentals and application. Third

edition. Benjamin/Cummings Pub. Co. New York.

Brock. T. D. 1979. Biology of Microorganisms. Third Edition. Englewood Cliffs. Prentice-Hall.

De Witt. W. 1977. Biology of the cell. An Evolutionary Approach. W.B. Saunders Company.

Philadelphia , London , Toronto.

Kotpal ,R.L. and N.P. Bali. 2003. Concepts of Ecology. : Environmental and field biology.

Vishal Publishing Compamy.India.

Killham. K . 1994. Soil Ecology. Cambridge University Press, Cambridge. England.

Paul. E.A. and Clark. F. E. 1996. Soil Microbiology and Biochemistry. Academic Press.

Pelczar. M.J.Jr; R.D. Reid and E.C.S. Chan. 1977. Microbiology. Fourth Edition. New York.

McGraw-Hill.

David B Alexander, 2002. Bacteria and Archaea (chapter 3). In Principles and applications of

soil microbiology. Edited by David M Sylvia, J.J. Fuhrmann, Peter G Hartel and David A

Zuberer. Prentice Hall. Upper Saddle River, NJ 07458

Paul. E.A. and Clark. F. E. 1996. Soil Microbiology and Biochemistry. Academic Press.

Rangaswami . G and Bagyaraj, D. J. 2001. Agricultural Microbiology. Second edition. Prentice-

Hall of India Private Limited. New Delhi.Salle. A. J. 1983. Fundamentals Principles of

Bacteriology. Seventh edition. Tata McGraw

Publishing Company LTD. New Delhi.

Subba Rao. N.S. 2002. Soil Microbiology (fourth edition of soil microorganisms and plant

growth) Oxford and IBH Publishing CO. PVT. LTD. New Delhi.

Stevenson. F. J. 1982. Humus Chemistry. Wiley-Interscience, New York.

Kelly. D. P. 1978. Microbial Ecology. In K.W.A. Chater and H.J. Somerville (eds ). The oil

industry and microbial ecosystems. Heyden and Son , London .

Tilman. D. 1982. Resource Competition and Community Structure. Princeton Unioversity Press,

Princeton , NJ.

National Academy of Sciences. 1981. Microbial Processes : Promising Technologies for

Developing Countries. N.A.S. Washington, D.C.

Role of Ectomycorrhizae In Coffee Plantations

by Dr. Anand Titus and Geeta N. Pereira