OSU ENR 3000 Soil Science Packet 1

More soil in atmosphere or soil?

More carbon in the soil than in the atmosphere

Soil orders (12)

Most inclusive (broad) taxonomic class, covers large areas across the landscape and exhibit the greatest contrasts between themselves

What is soil

1-4 meters deep 1. A naturally occurring thin layer over the earths crust 2. Exists as an unconsolidated, porous medium (only requires a shovel and human power to dig it) 3. Composed of mineral particles, organic matter, and living biomass 4. Formed by weathering and decomposition process 5. Biologically active 6. Varies with depth and spatially across the landscape

Lots of water but not always when and when it's needed

22% rain falls on land mass (110,000 km^3)

Blue water

39% of the 22% of the total continental precipitation that collects in rivers lakes and groundwater

Green water

61% of the 22% of rain that falls onto continental land mass that is absorbed into soil and returns to atmosphere via evaporating

renewable resource

A natural resource that can be replaced at the same rate at which the resource is consumed Ex.crops, trees, wind, water

Soil and global carbon cycle issues

Ag, forestry, other land use emit 24% of all GHG

Us Historical Biomes..

Align with soil orders

Results of excess soil wetness

Anaerobic soil conditions Direct plant injury Reduced organic matter decomposition Interruption of nutrient cycling Release of greenhouse gas methane and nitrous oxide

Carbon cycle

CO2 in the atmosphere is fixed into carbon compounds by plants during photosynthesis. When the plant dies, these compounds are returned to the soil and most carbon is returned to the atmosphere

Soil food web and carbon cycle

Carbon flows from primary producers through different levels of consumers At each level, plant nutrients and CO2 are released for plant uptake

Soil food web

Carbon flows from primary producers throughout the primary, secondary, and higher level consumers

Soil erosion

Converts soil into sediment that is deposited into oceans or continents, which eventually becomes buried and forms sedimentary rock.

Organic matter

Dead matter decomposing

Sources of plant nutrients in soil

Decomposition of plants, animals and soil microorganisms Weathering of soil minerals and rocks Addition of fertilizer (organic or not) Manure, compost, biosolids (sewage sludge), kelp, and other organic amendments Legume fixation of nitrogen Ground rock products of lime, rock phosphate, and greensand Inorganic industrial byproducts such as wood ash or coal ash Atmospheric inputs such as nitrogen and sulfur from acid rain or nitrogen fixation by lightning Deposition of nutrient rich sediment from erosion and flooding

Waste pollution

Disposal or waste can result in serious pollution problems Ie "garbisol" or chemical/garbage soil

Mollisol

Ex Great Plains grasslands

Inceptisol

Ex Mixed Forest of Appalachian Mtns.

Spodosol

Ex NE Boreal Forest

Ultisol

Ex SE mixed/evergreen forest

Aridsol

Ex cool and hot deserts

Alfisol

Ex eastern deciduous forest

Gelisol

Ex trees Arctic tundra

Excess soil wetness and soil oxygen content

Excess soil wetness inhibits oxygen entry into soil, resulting in oxygen depletion and anaerobic soil conditions

The amount of precipitation that falls on the continental land mass is not enough to satisfy everyone on the planet, true or false?

False, this quantity would satisfy the need of everyone. But only a small fraction is captured for human use

Sensible heat

Heat from rising or falling air

Latent heat

Heat from water evaporation or condensation

Soil and compaction

Heavy machinery and other compaction leads to the loss of the ability of roots to penetrate the soil

Soil erosion from tillage

Intensive tillage results in the loss of soil tilth

Agricultural nutrient cycle

Large quantities of nutrients are removed with crop yield. Maintenance of plant productivity requires animal feed or fertilizers to input nutrients

Soil horizon

Layer of soil, roughly, that differs in properties from adjacent layers (above or below)

Biomass

Living organisms

Wind erosion

Made worse by plowing/tillage + drought + location I.e. Dust bowl 1937

Definition of soil

Naturally occurring thin layer over the earths crust that exists as an unconsolidated, porous medium composed of minerals organic matter and biomass formed by weathering and decomposition processes that is biologically active and varies spatially across the landscape and width depth

16 Essential Plant Nutrients

Nitrogen - macronutrients Phosphorus - macronutrients Potassium - macronutrients Calcium Magnesium Zinc Copper Boron Molybdenum Chlorine Also sometimes Sodium Silicon Nickel Cobalt is essential for nitrogen fixation by legumes Selenium and iodine are beneficial for humans and therefore should be in the soil but not required by the plant

Is soil renewable or nonrenewable

Nonrenewable because of the time scale at which soil develops They are fragile and susceptible to injury/devastation

Nutrient cycles

Nutrients cycle between the plant and the soil in a closed loop

Oxygen cycle

Oxygen gas in the atmosphere enters the soil where it oxidizes carbon compounds, forming CO2. CO2 returns to the atmosphere. Plants fixate CO2 and releases O2

Earths critical zone

Portion of the planet extending from the top of the tallest vegetation to the bottom of groundwater

The water cycle

Precipitation striking the land surface will either runoff across the soil surface (into waterways) or infiltrate into the soil

Soil erosion by water

Results in the loss of the most fertile top soil layer I.e. Iowa and Tennessee

Losses of plant nutrients from the soil

Runoff loss of dissolved nutrients in water moving across the soil surface Erosion causes the loss of nutrients in attached soil particles that are removed by wind or water Leaching loss of dissolves nutrients in water that moved through the soil out of the root area into groundwater or out of area because of drain lines Loss of gas to atmosphere through nitrogen loss due to volatilization and denitrification as part of nitrogen cycle disruption Crop removal - plant uptake and removal of nutrients with harvesting products

Soil differs from other non renewable resources because...

Soil can be used REUSED indefinitely without deterioration if managed for sustainability

View of soil as a natural resource

Soil is something humans can use. Study of soil in this case allows us to better manage this resource.

View of soil as component of terrestrial ecosystem

Soil should be preserved, protected, untouched, and studied simply because it is.

Vertisols

Soils developed from

Energy received at the ground surface is returned...

To the atmosphere in diurnal and seasonal cycles

Soil salinity from water misuse

Tap water can cause dryness / salt on the surface of the soil Salt crust will form on the surface of the soil. Salt precipitation within the surface layer of wool

Net radiation

The heat that effects the ground surface through the forms of latent heat, sensible heat, and ground heat.

Soil orders

The most inclusive taxonomic class, cover broad areas across the landscape and exhibit the greatest contrasts between themselves

Thermal energy exchange

The transfer of heat throughout the soil by radiation, conduction, and convection

Soil and the geologic cycle

Uplift brings rocks to the surface where they weather into soil. Soil erosion converts soil into sediment that is deposited into oceans or continents, which eventually becomes buried and forms sedimentary rock.

Geologic cycle

Uplift brings rocks to the surface where they weather into soils. Erosion convert rocks into sediment that is deposited in oceans or continents which form sedimentary rocks

Ground heat

Warms the soil during daylight and cools the soil after sunset

Blue water

Water collected in river lakes or groundwater 39% of the 22% of total rain that falls onto land mass

Soil participates in which earth cycles?

Water cycle Carbon cycle Oxygen cycle Many plant nutrient cycles Geologic cycle Surface thermal energy exchange

Green water

Water that is absorbed by soil and returned to atmosphere via evaporation - 61% of the 22 % total

nonrenewable resource

a resource that cannot be replaced Ex oil coal ore

Histosols

organic soils

Andisols

soils formed in volcanic ash

Entisols

soils with little or no morphological development