good morning! - food & farm forum€¦ · a square yard a few inches deep may contain from 500...
TRANSCRIPT
Good Morning!
Ron Godin, Ph.D. Agronomist/Soil Scientist CSU Extension Sustainable & Organic Agriculture Delta, CO 970.874.2197
“Making good decisions comes from experience, and experience comes from making bad decisions!” -Mark Twain
The Soil Livestock is a complex
and diverse mix of species that
represents the greatest
concentration of biomass
anywhere on the planet.
Its all about the LIVING SOIL!
What are Soils?
How do soils form? What are soils made up of?
Five Factors of Soil Formation: 1. Parent Material (mountains & old sea beds)
Mineral Particles = sand + silt + clay
Organisms (2.5% OM) = 50 tons/ac = 100,000 lbs of organisms! In a 50 ft x 50 ft garden = 6, 250 lbs of organisms!! = 3 + tons!!
Soils
Sand 0.2 - 0.005 cm Silt 0.005 - 0.0002 cm
Clay < 0.0002 cm
Relative Size of Soil Particles
Lightly negative charged
Sand
Silt
Clay
Factors of Soil Formation: 2. Topography 3. Climate (deserts = young soils, not in yrs but erosion) 4. Time (millions of years, 300 – 400 yrs = 1 inch of soil!!!) 5. Biota (above and below surface)
Feeding the SOIL that feeds the soil life that feeds your plants! Do this by adding organic matter
Improves decomposition of organic matter
Increased biological activity and diversity
Increasing the organic matter content of your soil increases: soil biological activity soil biological diversity
Improved
decomposition of
organic matter
leads to:
Release of plant nutrients
for crop uptake Improves soil
aggregation & soil
health and quality
Increases soil humus &
crop productivity
Healthy Soils & Healthy Crops = Healthy Food & People & Sustainable Communities
Release of plant nutrients
for crop uptake Improvement of
soil health & quality
Increased soil humus &
crop productivity
Its all about the LIVING SOIL!
We have unique challenges living in a desert Low precipitation reduces organic matter production High temperatures and low moisture enhance organic matter decomposition Tillage burns up (oxidizes) organic matter by introducing lots of air/oxygen into the soil Tillage severely reduces soil moisture and soil structure Increasing organic matter is a challenge – using mulches help!
Soil Cover Impacts Soil Temperature and moisture which Impacts Biological Growth
Living Plant (i.e. Cover Crop) Some Crop Residue
The Difficulty of Building Organic Matter
Humus 15 -35 lbs
60- 80 lbs
CO 2
3- 8 lbs 3- 8 lbs 10- 30 lbs
Biomass
(soil organisms)
1 year after soil incorporation
Complex humic compounds (Non-active pool)
Nonhumic compounds
(polysaccharides, Polyuronides, acids. Etc (Active pool)
13th Edition Brady
Oxidized
Organic residues: 100 lbs
*
The World Under Your Feet!
The World Under Your Feet!
Soil microbes cycle and recycle nutrients for soil life & plant life
Soil Life: 1. Microbial Life
A. Bacteria i. Colored bacteria ii. Actinomycetes iii. Sporogenic bacilli iv. Cyanobacteria
B. Archaea – similar to bacteria i. Extreme halophiles ii. Extreme thermophiles iii. Methanogens
C. Protozoa
C. Eucarya i. Fungi ii. Ciliates iii. Slime moulds iv. Flagellates v. Microsporidia
One teaspoon of health, living soil contains: 1 Billion Bacteria 100,000 protozoa 30 - 40 miles of fungal hyphae Role of Bacteria, Protozoa and Fungi • 1 billion bacteria - eat root exudates made up of
• simple sugars, carbon and carbohydrates • w/fungi break down organic matter plant nutrients!
• 100,000 protozoa – eat the bacteria and excrete plant nutrients! • 40 miles of fungal hyphae – protect the plant from pathogens & harmful microbes
• help the plant take up water & nutrients as it doubles root mass of the plant
Bacteria Most numerous – up to 2 billion per gram of soil Known number of species = 10,000 species Number of unknown species outnumber the known
Dig down to lift your spirits: soil bacteria act as antidepressants • Have you ever noticed that people who spend more time outdoors, particularly those who garden regularly, are often cheery? • While the exercise, sunshine and general health benefits of being outdoors contributes to a happy disposition, scientists have discovered that some of this cheer comes from a certain bacteria that lives in the soil. • Mycobacterium vaccae, a soil dwelling bacteria, has been found to affect our brains in a similar way to antidepressants. It activates brain cells to produce serotonin, a hormone that helps regulate mood and sleep. Low levels of serotonin are often correlated with moodiness, feeling down and depression. • Experiments on mice revealed this bacteria simulated the production of cytokines, indicating an increase in immune system activity, as well as an increase of serotonin in the brain. - AustralianScience.com
Actinomycetes
Archaea
Extreme thermophiles
Extreme halophiles
Methanogens
Fungi
Mycorrhizae
with without
Fungal Mycelia
Soil Arthropods
Role of soil Arthropods: 1. Shred organic matter making easier for microbes to
breakdown 2. Eat bacteria and fungi and mineralize plant nutrients! 3. Mix soil with their movements & burrows 4. Control pests as many are general predators
A square yard a few inches deep may contain from 500 –
200,000 arthropods
Earthworms! Top of the soil food chain microbial
Role of Earthworms in soil:
Role of Earthworms (ecosystem engineers) in soil: Improve soil structure (casts) Mixing of soil and soil layers Burry and shred organic residue Aid in the decomposition of organic matter They feed on and feed bacteria & fungi Increase infiltration/reduce erosion Increase water holding capacity Provide channels for root growth and air movement
Role of Worms in soils: 1. Consume microorganisms and excrete plant nutrients! 2. Stimulate microbial activity – breakup OM and inoculate it with
more microorganisms (casts) 3. Facilitate the cycling of plant nutrients (casts) 4. Mix and aggregate soils – improve soil structure with their casts
and movements 5. Increase infiltration of air and water into the soil, minimizing
erosion, increase drainage of soils!
Disrupted Soil Ecosystem
This soil is naked, hungry, thirsty and running a fever!
Earthworm in dire straits, occurs when the soil is too hot, too cold or too dry
Nutrient Cycling Inputs: Organic Matter - cover crops - crop residues - animal manures and animal & plant composts
The Role of the LIVING SOIL is:
Benefits of Legume Crops in cooperation with bacteria •Rhizobia: soil bacteria responsible for symbiotic nitrogen fixation on legume roots. • Rhizobia fixes atmospheric nitrogen for use by legume plants in exchange for food (sugars) from the plant that keep the bacteria living! • Rhizobia are species specific and seed must be inoculated the first time it is planted in a field.
20 years of similar tillage intensity and C inputs
but contrasting types of organic inputs
Crop residues
Cover Crops
Animal manure
Crop residues
Rapid decomposition and release of plant nutrients
Effects of Organic Matter on Soil Nutrients & Sustainability
Adapted from Building Soils for Better Crops
very slow decomposition
Cover crops (green)
Compost
sugars, cellulose proteins lignin humus
Bringing your soil back to life or injecting new life means growing cover crops, rotating crops and reducing tillage towards no tillage! Multi-species cover crops No till veggies, and other crops.
More types of seeds
more stable is the
cover crop mix
Growing your own organic matter to feed your soil!
Grow Cover Crops
Then mow and either: Leave on surface or
Lightly till in
Transplanting
Cover soils whenever possible – slows organic matter decomposition
No Recreational Tillage!
No Recreational Tillage!!!
For Sale: Mailbox Holder
The remedy for farmers who need a power fix!!
Tillage Tools?
You decide…
Crop Residue Management
Old Method?
Really Old Method?
If you must till don’t be hard on the soil/organisms
Sold!
Questions?
Thank You!!!