N UTRIENT C YCLING N ITROGEN C YCLING T HROUGH E COSYSTEMS Dr. Jeffrey R. Corney, Managing Director of the University of Minnesota’s Cedar Creek Ecosystem Science Reserve D. Kindersley Nitrogen Free

N UTRIENT C YCLING E NERGY F LOW N UTRIENT C YCLING Energy Flow, Carbon & Oxygen Cycling J. Corney

N UTRIENT C YCLING The Nitrogen Cycle McGraw-Hill Elmhurst 10% of naturally occurring available nitrogen is generated by lightning.

N UTRIENT C YCLING E NERGY F LOW N UTRIENT C YCLING Nitrogen Cycling Through an Ecosystem PRODUCERS DECOMPOSERS CONSUMERS ECOSYSTEM 1 o 2 o 3 o SOIL “SINK” N-cmpds OTHER SOURCES N J. Corney NO 3 - & NH 4 + N2&NOxN2&NOx ATMOSPHERE

N UTRIENT C YCLING Carbon vs. Nitrogen Cycles Nitrogen cycling is mostly soil based. Carbon cycling is mostly atmosphere based.

N UTRIENT C YCLING Carbon & Nitrogen Cycles Are Linked U.S. Dept of Energy

N UTRIENT C YCLING In the “Top Four” Elements for Life ASU Pearson

N UTRIENT C YCLING Roles of CARBON & NITROGEN: “Life as a House” If Carbon comprises the framing and roofing (FORM)… …then Nitrogen comprises the appliances (FUNCTION). E Patrol

N UTRIENT C YCLING Key Component of Life’s Molecules Hemoglobin & Chlorophyll Amino Acids & Proteins DNA & RNA UDEL Wikipedia NobelPrize.org

N UTRIENT C YCLING Carbon to Nitrogen (C:N) Ratios McGraw-Hill Plants ~ 25:1 Animals ~ 6:1

N UTRIENT C YCLING Atmospheric N 2 Nitrogen Is Abundant in Atmosphere …but, N 2 as a gas is relatively inert to life U.S. EPA

N UTRIENT C YCLING …but, only plants can absorb Nitrogen directly from the environment Forms of Nitrogen Available for Life Nitrogen Free

N UTRIENT C YCLING The Nitrogen Cycle

N UTRIENT C YCLING Organic vs. Inorganic Nitrogen Organisms consume other organisms and excrete inorganic wastes. Inorganic (mineral) nutrients are usable by plants, and are mobile in soil. Organic (immobile) nutrients are stored in soil organisms and organic matter. Organisms take up and retain nutrients as they grow. USDA-NRCS

N UTRIENT C YCLING Nitrogen Cycle (zoomed in)

N UTRIENT C YCLING N 2 Nitrogen Atmospheric Nitrogen Ammonifying Bacteria Nitrogen -Fixing Bacteria Fixing Nitrogen…

N UTRIENT C YCLING Nitrifying Bacteria Nitrosomonas Nitrobacter Getting to Nitrate…

N UTRIENT C YCLING Nutrients Need Water to Move ? DK Clipart Nutrient ions are mobile while in a solution of water. So, how do nutrients move in soil?

N UTRIENT C YCLING Composition of Soil PhysicalGeography.net

N UTRIENT C YCLING Interstitial Spaces U of Minnesota

N UTRIENT C YCLING Getting Nutrients to the Plants USDA-NRCS U of Georgia River Partners

N UTRIENT C YCLING Mychorrizhae: Plants & Fungi Together 90% of plant families have mychorrizhal associations. Agro-Genesis A symbiotic, mutualistic association between a fungus and the roots of plants.

N UTRIENT C YCLING Mychorrizhal Relationship Up Close Plant root Mycorrhizal structure Fungal hyphae USDA-NRCS

N UTRIENT C YCLING 2 Types of Mychorrizhal Relationships Nature Plant a Globe 10% of plant families, mostly woody species (e.g. pine, oak, birch) USDA-NRCS 80% of plant families, mostly herbaceous species (e.g. grasses, forbs) USDA-NRCS

N UTRIENT C YCLING Plant-Fungal Cellular Connection Cold Spring Harbor Oxford Journal Image Nature RHIZOSPHERE Area of soil immediately adjacent to plant roots and mychorrizhal structures.

N UTRIENT C YCLING Fungi Help Get Nutrients into Roots NO 3 - NH 4 + NO 3 - H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O H2OH2O M. Harrison

N UTRIENT C YCLING Nutrients Move from Roots to Shoots Tutor Vista Helicon

N UTRIENT C YCLING J. Corney

N UTRIENT C YCLING S OIL O RGANISMS & D ECOMPOSITION Dr. Jeffrey R. Corney, Managing Director of the University of Minnesota’s Cedar Creek Ecosystem Science Reserve Organic Garden

N UTRIENT C YCLING Formation of Soil Brooks-Cole

N UTRIENT C YCLING Soil Layers DK Clipart USDA-NRCS Surface Litter Top Soil Sub-Soil Rock

N UTRIENT C YCLING Absolute Science Cross-Section of Soil

N UTRIENT C YCLING Soil Ecosystem at Micro-level USDA-NRCS Rose & Elliot

N UTRIENT C YCLING Process of Decomposition of Animals McGraw-Hill

N UTRIENT C YCLING Process of Decomposition of Plants Brooks-Cole

N UTRIENT C YCLING Soil Food Chain Landscape for Life

N UTRIENT C YCLING Soil Food Web Brooks-Cole

N UTRIENT C YCLING Bacteria, Fungi, & Actinomycetes Decompose material, mineralize nutrients, fix nitrogen, help aggregate soil particles. USDA-NRCS

N UTRIENT C YCLING Annual Microbial Activity by Season USDA-NRCS

N UTRIENT C YCLING Protozoans Consume bacteria and fungi, releasing nutrients when excrete wastes. USDA-NRCS BLM Mauby

N UTRIENT C YCLING Nematodes & Springtails Rodale Consume bacteria, fungi, and protozoans, releasing nutrients when excrete wastes. TAMU USDA-NRCS

N UTRIENT C YCLING Mites, Sowbugs, Millipedes Shred plant litter and consume detritus, increasing ability for microbes to decompose material. USDA-NRCS EcoLibrary

N UTRIENT C YCLING Ants, Beetles, Spiders, Centipedes Predators that eat other consumers, controlling populations and excreting nutrients. USDA-NRCS Discover Life

N UTRIENT C YCLING Earthworms: “Soil Aerators” Mix soil layers, redistributing nutrients throughout soil, and aerate the soil. Cary Institute Science Daily WORM

N UTRIENT C YCLING Gophers & Ants: “Earth Movers” Move nutrient poor sub-layers of soil to the surface, helping enrich soil layers.

N UTRIENT C YCLING Soil Organisms By-the-Numbers USDA-NRCS 1 gram of soil

N UTRIENT C YCLING Soil Organisms By Type of Ecosystem USDA-NRCS

N UTRIENT C YCLING Soil Biodiversity by Ecosystem USDA-NRCS

N UTRIENT C YCLING Fun Facts About Soil The tips of small plant roots move through the soil with a twisting screw-like motion. Mature trees can have as many as 5 million active root tips. A single spade full of rich garden soil contains more species of organisms than can be found above ground in the entire Amazon rain forest. Although the soil surface appears solid, air moves freely in and out of it. The air in the upper 8 inches of a well-drained soil is completely renewed about every hour. The plants growing in a 2-acre wheat field can have more than 30,000 miles of roots, greater than the circumference of the Earth. The wonderful "earthy" smell of newly plowed ground is believed to result from chemicals produced by micro-organisms. One of these chemicals, called geosmin, is produced by actinomycetes, organisms that have some properties of both bacteria and fungi. Soil can act as either a sink or a source of greenhouse gases. An estimated 30 percent of the carbon dioxide, 70 percent of the methane, and 90 percent of the nitrous oxide released to the atmosphere each year pass through the soil. It takes about 4,000 to 6,000 pounds of crop residue per year to maintain the content of organic matter in a soil. Modern farming practices that minimize soil disturbance (plowing) and return plant residues to the soil, such as no-till farming and crop rotations, are slowly rebuilding the Nation's stock of soil organic matter. Of the carbon returned to the soil as plant residue, about 5 to 15 percent become tied up in the bodies of organisms and 60 to 75 percent is respired as carbon dioxide back to the atmosphere. Only 10 to 25 percent is converted to humus in the soil. “We know more about the movement of celestial bodies than about the soil underfoot.” ---Leonardo Da Vinci, circa 1500's “Every time you take a step in a mature Oregon forest, your foot is being supported on the backs of 16,000 invertebrates held up by an average total of 120,000 legs.” –Dr. Andrew Moldenke, Oregon State University. Even in agricultural soils, more than a thousand arthropod legs support your every step. One cup of soil may hold as many bacteria as there are people on Earth. Bacteria and actinomycetes are exceedingly tiny. Yet, because of their tremendous numbers, they make up half the living biomass in some soils. The weight of all the bacteria in one acre of soil can equal the weight of a cow or two. Actinomycetes have cells like bacteria, but grow as long filaments like fungi. Like fungi, they help degrade tough materials, but unlike fungi, they prefer high pH (over 7.0). A teaspoon of farm soil may contain tens of yards of fungi. The same amount of soil from a coniferous forest may hold tens of miles of fungi. Nematodes are amazingly diverse. Twenty thousand species have been described, but it is thought that 500,000 species may exist. Five thousand soil species have been described. Earthworms move from lower strata up to the surface and move organic matter from the soil surface to lower layers. Where earthworms are active, they can turn over the top 6 inches of soil in 10 to 20 years. A single spade full of rich garden soil contains more species of organisms than can be found above ground in the entire Amazon rain forest. One cup of soil may hold as many bacteria as there are people on Earth. The weight of all the bacteria in one acre of soil can equal the weight of a cow. A teaspoon of soil from a coniferous forest may hold tens of miles of fungi. The air in the upper 8 inches of a well-drained soil is completely renewed about every hour. The plants growing in a 2-acre field can have more than 30,000 miles of roots, greater than the circumference of the Earth. Mature trees can have as many as 5 million active root tips. SOURCE: USDA-NRCS

N UTRIENT C YCLING More Fun Facts About Soil The tips of small plant roots move through the soil with a twisting screw-like motion. Mature trees can have as many as 5 million active root tips. A single spade full of rich garden soil contains more species of organisms than can be found above ground in the entire Amazon rain forest. Although the soil surface appears solid, air moves freely in and out of it. The air in the upper 8 inches of a well-drained soil is completely renewed about every hour. The plants growing in a 2-acre wheat field can have more than 30,000 miles of roots, greater than the circumference of the Earth. The wonderful "earthy" smell of newly plowed ground is believed to result from chemicals produced by micro-organisms. One of these chemicals, called geosmin, is produced by actinomycetes, organisms that have some properties of both bacteria and fungi. Soil can act as either a sink or a source of greenhouse gases. An estimated 30 percent of the carbon dioxide, 70 percent of the methane, and 90 percent of the nitrous oxide released to the atmosphere each year pass through the soil. It takes about 4,000 to 6,000 pounds of crop residue per year to maintain the content of organic matter in a soil. Modern farming practices that minimize soil disturbance (plowing) and return plant residues to the soil, such as no-till farming and crop rotations, are slowly rebuilding the Nation's stock of soil organic matter. Of the carbon returned to the soil as plant residue, about 5 to 15 percent become tied up in the bodies of organisms and 60 to 75 percent is respired as carbon dioxide back to the atmosphere. Only 10 to 25 percent is converted to humus in the soil. “We know more about the movement of celestial bodies than about the soil underfoot.” ---Leonardo Da Vinci, circa 1500's “Every time you take a step in a mature Oregon forest, your foot is being supported on the backs of 16,000 invertebrates held up by an average total of 120,000 legs.” –Dr. Andrew Moldenke, Oregon State University. Even in agricultural soils, more than a thousand arthropod legs support your every step. One cup of soil may hold as many bacteria as there are people on Earth. Bacteria and actinomycetes are exceedingly tiny. Yet, because of their tremendous numbers, they make up half the living biomass in some soils. The weight of all the bacteria in one acre of soil can equal the weight of a cow or two. Actinomycetes have cells like bacteria, but grow as long filaments like fungi. Like fungi, they help degrade tough materials, but unlike fungi, they prefer high pH (over 7.0). A teaspoon of farm soil may contain tens of yards of fungi. The same amount of soil from a coniferous forest may hold tens of miles of fungi. Nematodes are amazingly diverse. Twenty thousand species have been described, but it is thought that 500,000 species may exist. Five thousand soil species have been described. Earthworms move from lower strata up to the surface and move organic matter from the soil surface to lower layers. Where earthworms are active, they can turn over the top 6 inches of soil in 10 to 20 years. Twenty thousand species of nematodes have been described, but it is thought that 500,000 species may exist. Every time you take a step in a mature forest, your foot is being supported on the backs of 16,000 invertebrates held up by an average total of 120,000 legs. There is an estimated one quadrillion individual ants on the planet; that’s approximately 150,000 ants for every one human being. Where earthworms are active, they can turn over the entire top 6 inches of soil in 10 to 20 years. Pocket gopher mounds can cover as much as 25% of a grassland’s ground surface, depositing on average 20 tons of soil per acre per year. SOURCE: USDA-NRCS

N UTRIENT C YCLING S USTAINABILITY I SSUES THE CONCERN: Nitrogen Deposition & Eutrophication “Too Much of a Good Thing”

N UTRIENT C YCLING S USTAINABILITY I SSUES Global Sources of Nitrogen Today Vitousek & Matson Scientific American

N UTRIENT C YCLING S USTAINABILITY I SSUES Haber-Bosch “Synthetic” Nitrogen Fritz Haber Carl Bosch Fertilizer 101 Menlo School Invented process in early 1900s

N UTRIENT C YCLING S USTAINABILITY I SSUES Nitrogen Use, Agricultural Revolution, and Human Population Growth Tilman

N UTRIENT C YCLING S USTAINABILITY I SSUES Soil Nitrogen Runoff from Fertilizer

N UTRIENT C YCLING S USTAINABILITY I SSUES Atmospheric Nitrogen Deposition

N UTRIENT C YCLING S USTAINABILITY I SSUES Excessive Nitrogen in Mississippi Watershed USGS

N UTRIENT C YCLING S USTAINABILITY I SSUES Process of Eutrophication

N UTRIENT C YCLING S USTAINABILITY I SSUES Eutrophication of Coastal Gulf Waters

N UTRIENT C YCLING Dr. Jeffrey R. Corney, Managing Director University of Minnesota Cedar Creek Ecosystem Science Reserve 2660 Fawn Lake Dr NE East Bethel, MN (763)