The document discusses microbial ecology and the composition of soil as an environment for microorganisms. It notes that soil is a complex ecosystem containing a vast array of microbes, plants, and animals. The lithosphere is composed of weathered rock, humus, and nutrients. The rhizosphere around plant roots contains associated bacteria, fungi, and protozoa. Microbes play important roles in soil, including nutrient provision, decomposition, nitrogen fixation, and preventing pathogens. Bacteria, actinomycetes, and fungi are the dominant microbial groups in soil and influence processes like nutrient cycling and plant growth.
Microbial interactions are ubiquitous, diverse, critically important in the function of any biological community.
The most common cooperative interactions seen in microbial systems are mutually beneficial. The interactions between the two populations are classified according to whether both populations and one of them benefit from the associations, or one or both populations are negatively affected.
Microbial interactions are ubiquitous, diverse, critically important in the function of any biological community.
The most common cooperative interactions seen in microbial systems are mutually beneficial. The interactions between the two populations are classified according to whether both populations and one of them benefit from the associations, or one or both populations are negatively affected.
he rhizosphere is the narrow region of soil or substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome.
The phyllosphere is a term used in microbiology to refer to the total above-ground portions of plants as habitat for microorganisms.
Soils give a mechanical support to plants from which they extract nutrients. soil provides shelters for many animal types, from invertebrates such as worms and insects up to mammals like rabbits, moles, foxes and badgers. It also provides habitats colonised by a staggering variety of microorganisms. This module is about the microbial life in soils.
Soil organic matter has long been recognized as one of the most important components in maintaining soil fertility, soil quality, and agricultural sustainability. The soil zone strongly influenced by plant roots, the rhizosphere, plays an important role in regulating soil organic matter decomposition and nutrient cycling. Processes that are largely controlled or directly influenced by roots are often referred to as rhizosphere processes. These processes may include exudation of soluble compounds, water uptake, nutrient mobilization by roots and microorganisms, rhizosphere-mediated soil organic matter decomposition, and the subsequent release of CO2 through respiration. Rhizosphere processes are major gateways for nutrients and water. At the global scale, rhizosphere processes utilize approximately 50% of the energy fixed by photosynthesis in terrestrial ecosystems, contribute roughly 50% of the total CO2 emitted from terrestrial ecosystems, and mediate virtually all aspects of nutrient cycling. Therefore, plant roots and their rhizosphere interactions are at the center of many ecosystem processes. However, the linkage between rhizosphere processes and soil organic matter decomposition is not well understood. Because of the lack of appropriate methods, rates of soil organic matter decomposition are commonly assessed by incubating soil samples in the absence of vegetation and live roots with an implicit assumption that rhizosphere processes have little impact on the results. Our recent studies have overwhelmingly proved that this implicit assumption is often invalid, because the rate of soil organic matter decomposition can be accelerated by as much as 380% or inhibited by as much as 50% by the presence of live roots. The rhizosphere effect on soil organic matter decomposition is often large in magnitude and significant in mediating plant-soil interactions.
Plant microbe interaction by dr. ashwin chekeAshwin Cheke
PLANT MICROBE – INTERACTIONS AND THEIR MUTUAL BENEFITS IN ENHANCING SOIL HEALTH AND AGRICULTURAL PRODUCTION ,
IT ALSO INCREASE CROP PRODUCTIVITY AND IMPROVE SOIL HEALTH
Soil is an ecological niche contains all major groups of microorganism - bacteria, fungi, algae, protozoa and virus, but bacteria are most numerouse each play a vital role in the ecological diversity.
Agricultural Microbiology: Role of microbes in soil fertilitySarthakMoharana
Description on different microbes which plays role in maintaining soil fertility.
Fertile soils teem with microorganisms, which directly contribute to the biological fertility of that soil.
Biological fertility is under-studied and our scientific knowledge of it is incomplete.
In addition to fertility, soil microorganisms also play essential roles in the nutrient cycles that are fundamentally important to life on the planet.
In the past, agricultural practices have failed to promote healthy populations of microorganisms, limiting production yields and threatening sustainability.
Scientific research is exploring new and exciting possibilities for the restoration and promotion of healthy microbial populations in the soil.
‘Soil is essential for the maintenance of biodiversity above and below ground. The wealth of biodiversity below ground is vast and unappreciated: millions of microorganisms live and reproduce in a few grams of topsoil, an ecosystem essential for life on earth…’
From: Australian Soils and Landscape, An Illustrated Compendium
he rhizosphere is the narrow region of soil or substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome.
The phyllosphere is a term used in microbiology to refer to the total above-ground portions of plants as habitat for microorganisms.
Soils give a mechanical support to plants from which they extract nutrients. soil provides shelters for many animal types, from invertebrates such as worms and insects up to mammals like rabbits, moles, foxes and badgers. It also provides habitats colonised by a staggering variety of microorganisms. This module is about the microbial life in soils.
Soil organic matter has long been recognized as one of the most important components in maintaining soil fertility, soil quality, and agricultural sustainability. The soil zone strongly influenced by plant roots, the rhizosphere, plays an important role in regulating soil organic matter decomposition and nutrient cycling. Processes that are largely controlled or directly influenced by roots are often referred to as rhizosphere processes. These processes may include exudation of soluble compounds, water uptake, nutrient mobilization by roots and microorganisms, rhizosphere-mediated soil organic matter decomposition, and the subsequent release of CO2 through respiration. Rhizosphere processes are major gateways for nutrients and water. At the global scale, rhizosphere processes utilize approximately 50% of the energy fixed by photosynthesis in terrestrial ecosystems, contribute roughly 50% of the total CO2 emitted from terrestrial ecosystems, and mediate virtually all aspects of nutrient cycling. Therefore, plant roots and their rhizosphere interactions are at the center of many ecosystem processes. However, the linkage between rhizosphere processes and soil organic matter decomposition is not well understood. Because of the lack of appropriate methods, rates of soil organic matter decomposition are commonly assessed by incubating soil samples in the absence of vegetation and live roots with an implicit assumption that rhizosphere processes have little impact on the results. Our recent studies have overwhelmingly proved that this implicit assumption is often invalid, because the rate of soil organic matter decomposition can be accelerated by as much as 380% or inhibited by as much as 50% by the presence of live roots. The rhizosphere effect on soil organic matter decomposition is often large in magnitude and significant in mediating plant-soil interactions.
Plant microbe interaction by dr. ashwin chekeAshwin Cheke
PLANT MICROBE – INTERACTIONS AND THEIR MUTUAL BENEFITS IN ENHANCING SOIL HEALTH AND AGRICULTURAL PRODUCTION ,
IT ALSO INCREASE CROP PRODUCTIVITY AND IMPROVE SOIL HEALTH
Soil is an ecological niche contains all major groups of microorganism - bacteria, fungi, algae, protozoa and virus, but bacteria are most numerouse each play a vital role in the ecological diversity.
Agricultural Microbiology: Role of microbes in soil fertilitySarthakMoharana
Description on different microbes which plays role in maintaining soil fertility.
Fertile soils teem with microorganisms, which directly contribute to the biological fertility of that soil.
Biological fertility is under-studied and our scientific knowledge of it is incomplete.
In addition to fertility, soil microorganisms also play essential roles in the nutrient cycles that are fundamentally important to life on the planet.
In the past, agricultural practices have failed to promote healthy populations of microorganisms, limiting production yields and threatening sustainability.
Scientific research is exploring new and exciting possibilities for the restoration and promotion of healthy microbial populations in the soil.
‘Soil is essential for the maintenance of biodiversity above and below ground. The wealth of biodiversity below ground is vast and unappreciated: millions of microorganisms live and reproduce in a few grams of topsoil, an ecosystem essential for life on earth…’
From: Australian Soils and Landscape, An Illustrated Compendium
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Diabetes is a rapidly and serious health problem in Pakistan. This chronic condition is associated with serious long-term complications, including higher risk of heart disease and stroke. Aggressive treatment of hypertension and hyperlipideamia can result in a substantial reduction in cardiovascular events in patients with diabetes 1. Consequently pharmacist-led diabetes cardiovascular risk (DCVR) clinics have been established in both primary and secondary care sites in NHS Lothian during the past five years. An audit of the pharmaceutical care delivery at the clinics was conducted in order to evaluate practice and to standardize the pharmacists’ documentation of outcomes. Pharmaceutical care issues (PCI) and patient details were collected both prospectively and retrospectively from three DCVR clinics. The PCI`s were categorized according to a triangularised system consisting of multiple categories. These were ‘checks’, ‘changes’ (‘change in drug therapy process’ and ‘change in drug therapy’), ‘drug therapy problems’ and ‘quality assurance descriptors’ (‘timer perspective’ and ‘degree of change’). A verified medication assessment tool (MAT) for patients with chronic cardiovascular disease was applied to the patients from one of the clinics. The tool was used to quantify PCI`s and pharmacist actions that were centered on implementing or enforcing clinical guideline standards. A database was developed to be used as an assessment tool and to standardize the documentation of achievement of outcomes. Feedback on the audit of the pharmaceutical care delivery and the database was received from the DCVR clinic pharmacist at a focus group meeting.
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Micro RNA genes and their likely influence in rice (Oryza sativa L.) dynamic ...Open Access Research Paper
Micro RNAs (miRNAs) are small non-coding RNAs molecules having approximately 18-25 nucleotides, they are present in both plants and animals genomes. MiRNAs have diverse spatial expression patterns and regulate various developmental metabolisms, stress responses and other physiological processes. The dynamic gene expression playing major roles in phenotypic differences in organisms are believed to be controlled by miRNAs. Mutations in regions of regulatory factors, such as miRNA genes or transcription factors (TF) necessitated by dynamic environmental factors or pathogen infections, have tremendous effects on structure and expression of genes. The resultant novel gene products presents potential explanations for constant evolving desirable traits that have long been bred using conventional means, biotechnology or genetic engineering. Rice grain quality, yield, disease tolerance, climate-resilience and palatability properties are not exceptional to miRN Asmutations effects. There are new insights courtesy of high-throughput sequencing and improved proteomic techniques that organisms’ complexity and adaptations are highly contributed by miRNAs containing regulatory networks. This article aims to expound on how rice miRNAs could be driving evolution of traits and highlight the latest miRNA research progress. Moreover, the review accentuates miRNAs grey areas to be addressed and gives recommendations for further studies.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
2. Organization of Ecosystems
Biosphere – thick envelope of life that surrounds the earth’s surface
• Made up of:
• hydrosphere (water)
• lithosphere (soil)
• atmosphere (air)
• Maintains and creates the conditions of temperature, light, gases,
moisture, and minerals required for life processes
• Biomes- particular climatic regions
• Terrestrial biomes- grassland, tropical rainforest, temperate and tundra.
• Aquatic biomes- freshwater biomes and marine biomes.
3. • Communities – the association of organisms that live together and
that exhibit well-defined nutritional or behavioral interrelationships
• Population – organisms of the same species within a community
• Habitat – the physical location in the environment to which an
organism has adapted
• Niche – overall role that a species, or population, serves in a
community; nutritional intake, position in the community, and rate of
population growth
4. Ecology (oicos – house, hold, logos - doctrine) - science about legitimacies of creation and
functioning of biological systems and their mutual relation with an environment.
The microecology is the science about places of invading of microorganisms and their
ecological links.
At learning a microbial ecology use the same concepts, as well as in a common ecology.
Main of them are the following: population - an elementary evolutional unit (structure) of
a definite species;
biotope - site, habitation of a population, for parasites - place of their localization in an
organism;
microbiocenosis - microbial assemblage, association, that is collection of populations of
different species of microorganisms, which dwell(live) in the defined biotope (for example,
in an oral cavity, reservoir);
Ecosystem - system, in which enters a biotope and microbiocenosis
5. • Is the study of numerous interrelationships between microorganisms
and the world around them;
how microbes interact with other microbes
how microbes interact with organisms other than microbes
and how microbes interact with the non-living world around them
6. From old times it is known, that the microorganisms are omnipresent that is
ubiquitous organisms.
Huge quantities of them meet in soil, water and air.
The environment of their habitation is plants, animal, man.
Everywhere bacteria are existed as microbiocenoses.
The modern microbial biocenoses were generated as a result of durable evolution.
Mutual relation (cohabitation) of different species of microbes among
themselves and with other forms of life are called symbiosis.
7.
8.
9.
10.
11. Types of symbioses
1. Neutralism - the populations, existing in one biotope do not stimulate and do not
oppress each other.
2. Mutualism - mutually advantageous cohabitation; one population synthesizes
materials (matter), which are the basis of power supply for another (for example,
legume bacteria and bean plants, aerobic and anaerobic bacteria in an organism of
the man).
3. Commensalism - such form of symbiosis, at which one of jointly living
populations extracts for herself advantage(benefit), but does not put a harm of
other population. The commensalism is characteristic for many inhabitants of
human body.
12. Types of symbioses
4. Antagonism - oppression of one population another. The microbes –
antagonists produce antibiotics, bacteriocines, fatty acids, which cause
destruction of bacteria or delay their reproduction.
5. Parasitism - such kind of symbiosis, at which one population (parasite) brings
harm to the host, and for itself has a benefit. The causative agents of bacterial,
virus and fungi illnesses concern to microbes - parasites.
6. Synergism- the interaction or cooperation of two or more organizations, substances,
or other agents to produce a combined effect greater than the sum of their separate
effects.
13. Soil is alive…
For example, in 1g of soil:
>100,000,000 bacterial cells
>11,000 species of bacteria
Also fungi and larger animals
14. Microflora of the soil
The soil is the major environment for a habitation of microorganisms.
The first bacteria, as well as all alive ones, have appeared in water. However in more later geological
periods, when on a surface of globe the soil was derived, it became main habitation of microorganisms and
main arena of their vital activity.
The amount of bacteria in one gram of soil can be very great - from 200 millions up to 10 billions.
Manured and ploughing ground are stocked with microorganisms most densely.
The soil of woods, moor, the sands of desert contain few microbes.
The most surface sphere of soil (crust by width of 2-3 mm) is very poor by microorganisms. A desiccation
and the solar rays perniciously influence them.
The ground mass of bacteria is on depth 10-20 cm.
15. The microflora of soil includes hundreds of species of bacteria, viruses, protozoa, actinomyces and
fungi.
It is various species of putrefactiving, nitrifying, denitrifying, nitrogen-fixing bacteria.
The most often inhabitants of soil are the representatives of genus Azotobacter, Nocardia, and
Clostridium.
Many bacteria of genus Rhisobium, Nitrosomonas, Nitrosospira, Nitrobacter, Pseudomonas are very
often found.
Almost always there are denitrifying bacteria (B.denitrificans), ammonifying microbes (Urobacillus
pasteurii, Urobacillus leybii), numerous iron bacteria and sulphur-bacteria.
All of them play the great role in a turnover of materials in a nature, improve productivity of our fields,
provide life on the Earth.
The microorganisms of soil take an active part in all processes of transformation of materials and energy:
synthesis of a biomass, biological nitrogen fixation, fermentation, denitrification of the cycle sulfur,
iron lactas, phosphorum, carboneum and other elements.
16. SOILS AS AN ENVIRONMENT FOR MICROORGANISMS
A soil scientist would describe soil as weathered rock combined with organic matter and
nutrients.
An agronomist would point out that soil supports plant life.
However, a microbial ecologist knows that the formation of organic matter and the growth
of plants depend on the microbial community within the soil.
Microbial activities can lead to the formation of minerals such as dolomite; microbial
activity also occurs in deep continental oil reservoirs, in stones, and even in rocky
outcrops. These microbes are dependent on energy sources from photosynthetic protists
and nutrients in rainfall and dust.
17. A typical soil habitat contains a mixture
of clay, silt, and sand along with soil
organic matter.
Roots, animals (e.g., nematodes and
mites), as well as chemoorganotrophic
bacteria consume oxygen, which is
rapidly replaced by diffusion within the
soil pores where the microbes live.
Soil Habitat
18. The Composition of the Lithosphere
• Soil is a dynamic, complex ecosystem with a vast array of microbes,
animals, and plants.
• Lichens – symbiotic associations between a fungus and a
cyanobacterium or green algae
• produce acid that releases minerals from rocks
• Humus – rich moist layer of soil containing plant and animal debris being
decomposed by microbes
• Rhizosphere – zone of soil around plant roots contains associated
bacteria, fungi and protozoa
• Mycorrhizae – symbiotic organs formed between fungi and certain plant
roots
19. What Are Microbes Doing For Plants?
• Providing nutrition
• Mycorrhiza – absorb water and nutrients
• Nitrogen fixation– rhizobacteria
• Decomposition of dead material into plant usable
• Store nutrients in their cells
• Preventing pathogens
• Bacteriocins and antibiotics
• Competition
• Molding the architecture of the soil
• Aeration
• Aggregates that enhance water retention
20. What does the plant do to encourage the microbiota?
• Secretes small molecules such as sugars and amino acids, peptides
• Far more life in the rhizosphere than away from it.
• A large part of the plants energy stores are secreted into the soil.
• Protection: allows some bacteria to live in plant cells.
22. Bacteria
• -are more dominant group of microorganisms in the soil and equal to
one half of the microbial biomass in soil.
• Population 100,000 to several hundred millions for gram of soil -
Autochthonous - Zymogenous groups.
• Majority are Heterotrophs. (Common soil bacteria - Arthrobacter,
Bacillus, Clostridium, Micrococcus).
23. Plant Growth Enhancing by Bacteria
• Certain strains of the soil bacteria Pseudomonas fluorescens have anti-fungal
activity that inhibits some plant pathogens.
• P. fluorescens and other Pseudomonas and Xanthomonas species can increase plant
growth in several ways.
• They may produce a compound that inhibits the growth of pathogens or reduces
invasion of the plant by a pathogen. They may also produce compounds (growth
factors) that directly increase plant growth.
• In the future, farmers may be able to inoculate seeds with anti-fungal bacteria, such
as P. fluorescens, to ensure that the bacteria reduce pathogens around the seed and
root of the crop.
24. • - intermediate group between bacteria and fungi. Numerous and widely
distributed in soil.
• Abundance is next to bacteria. 104 - 108/g soil.
• 70% of soil actinomycetes are Streptomyces.
• Many of them are known to produce antibiotics. (e.g. S. antibioticus)
• Population increases with depth of soil.
25. Characteristics of Actinomycetes
• Similarities to bacteria
– Prokaryotic
– sensitive to anti-bacterials
– resemble bacteria in size, shape and gram-staining properties.
• Similarities to fungi
– shape and branching properties, spore formation
– Reproduction mechanism
27. Fungi
• More numerous in surface layers of well-aerated and cultivated soils-dominant in
acid soils.
• Common genera in soil are Aspergillus, Mucor, Penicillium Trichoderma, Alternaria,
Rhizopus.
• Algae – found in most of the soils in number ranges from 100 to 10,000 per g
• Decomposers – saprophytic fungi – convert dead organic material into fungal
biomass, carbon dioxide (CO2), and small molecules, such as organic acids. Like
bacteria, fungi are important for immobilizing, or retaining, nutrients in the soil.
• In addition, many of the secondary metabolites of fungi are organic acids, so they
help increase the accumulation of humic-acid rich organic matter that is resistant to
degradation and may stay in the soil for hundreds of years.
28. • Mutualists – the mycorrhizal fungi – colonize plant roots. In exchange for carbon from
the plant, mycorrhizal fungi help solubilize phosphorus and bring soil nutrients
(phosphorus, nitrogen, micronutrients, and perhaps water) to the plant.
• Pathogens or parasites, cause reduced production or death when they colonize roots
and other organisms. Root-pathogenic fungi, such as Verticillium, Pythium, and
Rhizoctonia, cause major economic losses in agriculture each year.
• Many fungi help control diseases. For example, nematode-trapping fungi that
parasitize disease-causing nematodes, and fungi that feed on insects may be useful as
biocontrol agents.
29. Fungi
• abundant after bacteria
• food sources for other organisms
• beneficial symbiotic relationships with plants or other organisms
• reduce crop residues
• biochemically process nutrients to improve the soil
Factors effecting growth of fungi
• quality as well as quantity of organic matter in the soil has a direct correlation to the
growth of fungi
• Fungi are abundant in acidic areas compared to bacteria
• Fungi also grows well in dry, arid soils (aerobic, or dependent on oxygen)
30. Algae
• Algae can make its own nutrients through a process known as photosynthesis
• distributed evenly wherever sunlight and moderate moisture is available
– do not have to be on the soil surface or directly exposed to sun rays
– can live below the soil surface as long as the algae has uniform temperature and
moisture conditions.
• Possess the character of symbiotic nitrogen fixation in association with other organisms
like fungi, mosses, and liverworts
• Association fix nitrogen symbiotically in rice fields.
• Plays important role in the maintenance of soil fertility especially in tropical soils.
• Add organic matter to soil when die and thus increase the amount of organic carbon in
soil
31. • Most of soil algae (especially BGA) act as cementing agent in binding soil particles and
thereby reduce/prevent soil erosion
• Mucilage secreted by the BGA is hygroscopic in nature and thus helps in increasing
water retention capacity of soil for longer time/period
• Soil algae through the process of photosynthesis liberate large quantity of oxygen in
the soil environment and thus facilitate the aeration in submerged soils or oxygenate
the soil environment
• Help in checking the loss of nitrates through leaching and drainage especially in un-
cropped soils
• They help in weathering of rocks and building up of soil structure
32. Soil Protozoa
• Unicellular – population ranges from 10,000 to 100,000 per g of soil.
• Most of the soil forms are flagellates, amoebae or ciliates.
• Derive their nutrition by devouring soil bacteria.
• Abundant in upper larger of the soil.
• They are regulating the biological equilibrium in soil.
• Ciliates –paramecia eat bacteria and each other
• Amoeba – feeds on bacteria and parmecia
• Release nitrogen from bacteria
• Protozoa can be split up into three categories: flagellates, amoebae, and
ciliates
33. Types of flagellates
• smallest members of the protozoa group, and can be divided
further based on whether
– Non chlorophyll-containing flagellates found mostly in soil and
flagellates that contain chlorophyll typically occur in aquatic
conditions.
– distinguished by their flagella
34. Amoeba
• larger than flagellates and move in a different way
• slug-like properties and pseudopodia
• does not have permanent appendages
Ciliates
• largest of the protozoa group
• move by means of short, numerous cilia
35. Importance of soil microorganisms
• Involved in nutrient transformation process
• Decomposition of resistant components of plant and animal tissue
• Role in microbial antagonism
• Participate in humus formation
• Predator to nematodes
• Surface blooming reduces erosion losses
• Improves soil structure
• Maintenance of biological equilibrium
37. Assignment (1 page each)
• Cold moist soil (Soils in cold environments; Arctic, Antarctic, or
alpine regions)
• Desert soil
• Geologically Heated Hyperthermal Soils (-found in such areas
as Iceland, the Kamchatka peninsula in eastern Russia,
Yellowstone National Park, and at many mining waste sites)
• State the Microorganisms found in each