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Soils
Soil Science & Management
| Questions | Answers |
|---|---|
| Definition of soils | An accumulation of organic and mineral materials, living forms, water and air on the surface of the earth in which plants grow. |
| Organic matter | Matter derived from living organisms, dead plants and plant parts, dead animals. |
| Minerals | Inorganic solid particles of soil |
| Living Forms | All living entities that live in the soil |
| Water | An average mineral soil is composed of 25% water |
| Air | An average mineral soil is composed of 25% air |
| ORGANIC SOILS | Soils formed from plant and animal residues in ponded and/or cold wet areas where organic decomposition is slow. In order to be classified an organic soil it has to contain more than 20% organic matter. .5% of US soils are organic. |
| MINERAL SOILS | A soil consisting predominately of mineral matter and having its properties determined predominately by the mineral material. Most soils are mineral soils. |
| Functions of Soils in Plant Growth | Provides support, Provides nutrition, Provides water Provides air, Stores heat |
| Agricultural /Horticultural uses of soil | Cropland, Grazing Land, Forest, Landscapes |
| Non Agricultural uses of Soil | Supplies energy (coal,oil), Building materials, Supports structures, Provides areas for recreation, Absorbs waste and acts as a filter |
| Soil Matrix | a three phase system of solid, liquid and gas |
| IDEAL MINERAL SOIL | 25% water, 25% air, 45% minerals, 5% OM |
| Soil is | a critical resource, which needs to be sustained or improved. |
| Soil degradation | practices that reduce soils productivity (quality) |
| Soil destruction | practices that make soils totally unproductive |
| Best Management Practices (BMP) | “practices that preserve soil and water resources while being profitable and practical for the soil user” (Plaster) |
| We need to protect our natural ecosystems such as wetlands, prime farmland and forests. They serve important functions in the preservation of the planet. | |
| “Over the past century, human activities have released large amounts of carbon dioxide and other greenhouse gases into the atmosphere. The majority of greenhouse gases come from burning fossil fuels to produce energy, although deforestation, industrial pr | |
| Greenhouse gases act like a blanket around Earth, trapping energy in the atmosphere and causing it to warm. This phenomenon is called the greenhouse effect and is natural and necessary to support life on Earth. However, the buildup of greenhouse gases can | |
| The choices we make today will affect the amount of greenhouse gases we put in the atmosphere in the near future and for years to come.” http://www.epa.gov/climatechange/basics/ | |
| Our practices as horticulturists/agronomists can significantly increase or reduce the amount of heat trapped in the atmosphere. Use of manufactured fertilizers increases heat entrapment and increases global warming. Increased use of organic matter withdra | |
| can moderate the climate change. Trees store a great deal of carbon and planting trees helps to moderate climate change also. | |
| Carbon sequestration | Process of storing carbon in soil, plants or other places |
| Carbon sinks | Places where carbon is stored |
| SOIL (GENESIS) FORMATION | The mode of origin of the soil with special references to the processes or soil forming factors responsible for the development of the solum (true soil) from unconsolidated materials (Plaster) |
| Soil Pedology | The study of soil formation |
| THE FIVE FACTORS OF SOIL FORMATION | Parent Materials, Climate, Organisms (Biosphere) , Topography, Time |
| The type of soil developed depends on | the amount of time a parent material on a specific topography is exposed to the effects of climate and biota. |
| Factors of Soil Development PARENT MATERIALS | Organic Materials, Mineral Materials |
| Mineral Materials | Rocks -complex mineral aggregate |
| Types of Rock | Igneous, Sedimentar, Metamorphic |
| Ways Rock type influence soil formation | Different Rates of Weathering, Different Nutrient Content, Different Particle Sizes |
| Rock Weathering | Physical Weathering |
| Physical Weathering of Rock | Expansion and contraction, grinding, root pressure |
| Chemical Weathering of Rock | Solution, Hydrolysis and Hydration |
| Materials soils can be formed from: | Residual materials, transported materials, cumulose |
| Residual Materials | Bedrock |
| Transported Materials | Materials moved by Water, Wind, Ice or Gravity |
| Materials Moved by Water | Fresh flowing Water – Alluvium, Salt Water - Marine Sediments |
| Materials Moved by Wind | Eolian Deposits – Loess, Sand dunes, Volcanic Ash |
| Materials Moved by Ice | Glacial Drift-All Material deposited by the glaciers, Glacial Till - deposited by the glacier themselves (Moraines), Glacial Outwash - deposited by glacial melt waters, Lacustrine deposits- deposits left on the bottom of Glacial Lakes |
| Materials Moved by Gravity | Colluvium |
| Cumulose- Organic deposits | |
| Factors of Soil Development Climate | Effects Organic Matter production and decomposition, chemical and physical weathering and leaching |
| Climate Temperature | Soils develop more rapidly in warm climates |
| Climate Rainfall | Soils develop more rapidly in areas with high rainfall |
| Factors of Soil Development Effects of BIOTA (Living Organisms) | Vegetation, Burrowing animals, Microorganisms |
| Factors of Soil Development Topography | Soil development affected by Slope, Aspect (exposure) |
| Factors of Soil Development Time | Speed of soil development - Young soils, Mature soils, Old soils |
| 6th Factors of Soil Development | HUMANS |
| SOIL MORPHOLOGY | The physical nature of soils as exhibited by horizon differences and such physical properties as texture, porosity and color. |
| The soil body | Pedon, Polypedon |
| Pedon | A three dimensional body of soil with lateral dimensions large enough to permit the study of horizon shapes and relations (generally 3’ X 3’ X 5’) |
| Polypedon | A group of like pedons |
| Parts of a soil pedon | Soil Profile, Soil Horizon, Solum, Horizon Boundary |
| Soil Profile | The vertical section of soil through all its horizons and extending into the parent material. |
| Soil Horizon | A horizontal layer of soil, created by soil forming processes, that differs in physical, biological or chemical properties from adjacent layers. |
| Solum | the “true soil” .The upper, most weathered part of the soil profile that contains most of the plant roots .The A, E and B horizons |
| Horizon Boundary | A line between the two horizons. It can be indistinct, clear or abrupt |
| Master Horizons O, A, E, B, C, R | |
| O Horizon | Organic horizon |
| A Horizon | Topsoil. A combination of mineral and organic matter |
| E Horizon | Horizon of loss (eluviation). Fine clays, organic matter |
| and chemicals have leached out found in forest soils | |
| B Horizon | Subsoil Horizon of accumulation (illuviation). This is where materials from the A and E accumulate |
| C Horizon | Horizon of parent material. Unconsolidated material |
| R Horizon | Bedrock |
| Forest Horizon | rock or minerals, OM, thin LAYER, A, B then E - (O, A, E, B, C, R) |
| Grass Horizon | rock or minerals, grass then A, B – (A, B, C, R) |
| Subdivisions of the Master Horizons - Horizon subscripts | A lower case letter added to the Master horizons for further detail. (Example -Ap) See appendix 3 in Plaster |
| Subdivisions of the Master Horizons - Transition Horizons | Areas with the characteristics of both the above and |
| below horizons (example -AB) | |
| Soil forming processes which cause horizons to develop | Additions, Losses, Transformations, Translocations, of soil materials |
| SOIL CLASSIFICATION | grouping of soils into categories based on each soil's morphology (appearance and form) |
| USDA SOIL CLASSIFICATION SYSTEM | 6 Levels of Classification – Orders, Suborders, Great Groups, Subgroups, Families, Series |
| USDA Soil Classification System - Orders | (12) |
| The 4 soil orders that are present in NH | Entisols, Inceptisols, Histisols, Spodosols |
| Entisols | Little profile development |
| Inceptisols | Weakly developed profile |
| Histisols | Organic SoilsWetlands-area of predominately hydric (waterlogged soils) that can support a prevalence of water loving plants |
| Spodosols | Coniferous Forest Soils |
| Diagnostic Horizons | horizons with combinations of specific substances that are indicate certain kinds of soil development. Used to classify soils to the Order they are in. |
| USDA Soil Classification System - Suborders | (66) |
| USDA Soil Classification System Great Groups | (>320) |
| USDA Soil Classification System Subgroups | (>2000) |
| USDA Soil Classification System Families | (>8000) Families are defined largely on the basis of physical and mineralogical properties of importance to plant growth. The properties include texture, pH thickness of horizons, structure, consistency etc |
| USDA Soil Classification System Series | (>19,000) Soils that are essentially alike in all profile characteristics such as texture, structure, pH, and color, OM content, parent materials etc. |
| Soil Phase | Soils within a soil series that are subdivided as far as characteristics that affect soils uses and management- surface texture, slope, stoniness, etc. |
| SOIL PHYSICAL PROPERTIES | Texture, Structure, Density, Porosity, Permeability, Air, Consistence, Temperature, Color, |
| SOILTEXTURE | the relative proportions of the soil separates (in%) in the soil |
| Soil Separates | Sand, silt, and clay – (Size of separates and Classes of sand) |
| Textural Classes | 4 Broad Classes - Sand, Silt, Clay, Loam |
| 12 USDA Textural Classes Coarse textured | Sand, Loamy Sand, Sandy Loam |
| 12 USDA Textural Classes Medium textured-Loam, Silt Loam, Silt | |
| 12 USDA Textural Classes Fine textured | Sandy Clay Loam, Clay Loam, Silty Clay Loam, Sandy Clay, Silty Clay, Clay |
| Rock Fragments | Types and Sizes, Use in describing soil texture |
| Ways to determine Texture | By feel, By finding % of the soil separates and then comparing it to the textural triangle. |
| Ways to find % of soil separates | By weight (Bouyoucos hydrometer, Sieve), By volume (Mechanical analysis (SedimentationTest) |
| Particle size effects: | Internal surface area of soil, Pore size and number |
| The Importance of Texture in Soil Use Management – Qualities of: | 1. Coarse textured soils,2. Fine Textured soils, 3.Mediumtexturedsoils |
| Management of texture | 1. Select a crop to fit the soil texture or buy land that fits what you are growing, 2. Manage the soil for the texture 3. Add Organic Matter |
| Soil Structure | The arrangement of soil particles into aggregates and the arrangement of aggregates in the soil profile. |
| Soil Structure - Aggregate | Secondary units or granules composed of many soil particles bound or cemented together by organic substances, Iron Oxides, Carbonates, Clays or Silica |
| Soil Structure - Clod | Soil broken into any shape by artificial means, i.e. digging, tillage. |
| Soil Structure - Ped | A natural aggregate |
| Peds are described by three characteristics | 1. Type (Shape), 2. Class (Size), 3. Grade (Strength of the peds and how much of the soil is in peds) |
| Ped Type | Crumb, Granular, Blocky, ( |
| Soil Structure | Class -very fine or very thin, fine or thin, medium, coarse or thick, very coarse or very thick. |
| Soil Structure | Grade - Weak, Moderate, Strong - |
| Soil Structure - Structure less Soils | 1. Single Grain, 2.Massive, 3.Puddled |
| Soil Density | The mass per unit volume of an object |
| Particle Density | The density of the solid soil particles excluding pore space |
| Bulk Density | Density of a volume of soil as it exists naturally including pore space and OM. |
| Uses of Bulk Density | 1. To evaluate soil compaction, 2. To calculate water storage capacity, 3. To calculate the weight of an acre furrow slice, 4. To calculate porosity by weight |
| Densities are measured in | g/cm3 or lbs/ft3 |
| Soil Pore Space | portion of the soil volume not occupied by solid matter. |
| Factors which cause pore space | ANSWER |
| % of pore space in soils | ANSWER |
| Types of pore space | micropores vs. macropores |
| Porosity | % pore space, can be measured by: 1. Volume, 2. Weight, |
| Soil Permeability | The ease in which air water and roots move through the soil |
| Hydraulic conductivity | measure of the rate of water movement through a soil |
| Perc Test | Test done that measures Hydraulic conductivity - used for 1. estimating irrigation needs, 2. installation of septic systems,3. reservoirs, sewage lagoons and landfills |
| SOIL TILTH | Physical condition of a tilled soil. Indicates ease of tillage, root penetration, seedling germination and growth |
| SOIL AIR ODR | Oxygen Diffusion Rate - The rate in which oxygen in the soil exchanges with oxygen in the atmosphere |
| Factors which reduce the ODR and soil aeration | 1. High amounts of clay, 2. Waterlogged soil, 3. Soil compaction of loams and clays 4. Organic Matter decomposition in soils with low ODR 5. Overmulching |
| Causes of soil compaction | 1. Cultivating when wet or over cultivating, 2. Cultivating at same depth (Hard pan or Plow Pan), 3. Heavy equipment, 4. Foot traffic |
| Ways to increase ODR and aeration in soils | 1. Installing drainage systems, 2. Incorporating OM in order to increase soil granulation, 3. Use of Chisel Plows and Ripper Bedders, 4. Using Soil Aerators on compacted soils (Spikes, Corers, Probes (Shattertines)) 5. Proper Use of Mulch |
| Soil Consistence | Characteristics of a soil in its response or resistance to pressure as described at various moisture content. This is caused by cohesion between soil, particles and adhesion between soil and other particles (mostly water).Looks at characteristics of stren |
| Strength | indicates the resistance of the soil to root penetration and how much power will be required to cultivate a soil. It is determined in the dry and moist stages. (dry hardness, moist firmness) |
| Plasticity and stickiness | indicate the amount and types of clay in the soil. Determined in the wet stage. |
| Plasticity | ability to take and hold a new shape when pressure is applied. |
| Stickiness | tendency of a soil to adhere to other objects |
| Soil Temperature is affected by | 1. Radiant Energy, 2. Air Temperature, 3. Soil Color, 4. Soil Moisture, 5 Soil Depth |
| Radiant Energy amount depends on: | 1. Time of Year, 2. Exposure, 3. Soil Cover |
| Types of soil cover | Plants, Mulches, Plastics, Organic mulches, Plant covers, Crop covers, poly greenhouses |
| Air Temperature | As air temperature fluctuates so does soil temp but not as quickly |
| Soil Color | If the color is caused by minerals then dark soils are warmer than light soils but if it's caused by organic matter a dark soil will warm up more slowly than a light soil |
| Soil Moisture | wet soils are cooler than dry soils |
| Soil Depth | from 0 to 12-16" (0 to 30-40cm) -daily temp fluctuations, below 3.3ft (1 M) -slow seasonal temp. fluctuations, below 20 ft (6.1 M) - no temp. fluctuations |
| Soil Temperature affects | 1.Microbial Activity, Weathering of Soil Minerals, Plant Growth |
| Microbial Activity | ceases at 32 F (10 C), largely inactive at 40 F (5 C), optimum temp 86 -95F (30-35 C) |
| Weathering of Soil Minerals | as temperature. increases so does physical and chemical weathering of soils |
| Plant Growth | 1. % and speed of germination- is low below 55 degrees F for most crops. All plants have an optimum temp for germination 2. Vegetative growth, flowering and fruiting -All crops have optimum temps, Growing degree days 3. Root growth - Root kill temps, root |
| Factors affecting soil color | 1. Organic matter/Humus content, 2. Soil drainage, 3. Soul Parent Materials, 4. Age, 5, Slope, 6. Leaching |
| Factors Affecting Soil Color - Organic matter/ Humus content | The higher the organic matter/humus content the darker the color - Moist or wet soils are darker than dry soils because organic matter does not break down Humus is what remains after the major portion of plant and animal residues have decomposed |
| Factors Affecting Soil Color - Soil Drainage | affects color especially of the subsoil 1. Grays and blues are poorly drained, Reds are well drained, Yellows are moist. |
| Mottles | (Redoxymorphic feature)es are spots or blotches of a different color interspersed with the dominant color in the horizon |
| Gleying | bluish, grayish or greenish colors in the soil which indicate long periods each year of water logged conditions and inadequate drainage |
| Factors Affecting Soil Color - Soil Parent Materials | Felsic Rock - light colored, Mafic Rock - dark colored |
| Factors Affecting Soil Color – Age | Older soils are usually lighter in color. |
| Factors Affecting Soil Color – Slope | Soils on the top of the slope are usually lighter than the bottom of the slope |
| Factors Affecting Soil Color - Leaching | White to light gray colors are found in leached sandy soils and E horizons |
| Color is described using | the Munsell Color Chart |
| SOIL CHEMISTRY | deals with the composition and properties of substances in the soil and with the reactions by which substances are produced from or converted into other substances |
| The chemical properties of the soil include | 1.Soil pH, 2.Cation and Anion Exchange Capacity, 3.Buffering Capacity |
| A Knowledge of Soil Chemistry is essential to be able to: | 1. Improve availability of nutrients to plants, 2. Avoid toxicity’s of elements to plants, 3. Utilize soil microbial populations, 4. Improve physical conditions of the soil, 5. Improve soil stability under loads, 6. Reduce amount of pollution of soil and |
| Chemical Composition of the soil | Oxygen, silicon and aluminum are the three most abundant elements in the earth’s crust, there are many other elements present in smaller amounts |
| Plant Nutrients | 17 essential elements for plant growth. The ones present in the soil are categorized as the Primary Macronutrients, the Secondary Macronutrients and the Micronutrients (trace elements) |
| Nutrient Ions | Cations (+ charge) and Anions (-charge) |
| Soil Colloids | Soil particle that is small enough to stay suspended in water for a long period of time . Particles less than 2 micrometers .Carries a charge which is usually negative |
| TYPES OF COLLOIDS | 1. Clay, 2. Organic Colloids (humus) |
| CHARACTERISTICS OF CLAY | 1.They are Secondary minerals, 2. They have a crystalline structure, 3. They have a charge which is usually negative. |
| Most clays are | 1. newly formed crystals reformed from the soluble products of the primary minerals, Some form from a slight change in a primary mineral -usually micas, 2. They have a Crystalline Structure, micelle- (clay particle ) flat plate like crystal made up of man |
| Negative charge in clays is caused by: | 1. Ionizable Hydrogen Ions, 2. Isomorphous substitution |
| Ionizable Hydrogen ions | When the hydrogen from hydroxide ions in the clay particle is ionized and goes into solution. The remaining oxygen has a negative charge. This is pH dependant. |
| Isomorphous substitution | The replacement of an atom of a higher charge with one of a lesser charge during the formation of a clay. This causes the clay to have a negative charge |
| TYPES OF CLAYS | 1.Silicate Clays, 2. Oxide (Sesquioxide) Clay |
| Silicate Clays | Amorphous Silicate Clays, Silicate Clays with a crystalline structure |
| Amorphous Silicate Clays - do not have crystalline structure, time or conditions have not been right (Allophane) | |
| Silicate Clays with a crystalline Structure | 1. Kandites -1:1 Clays -residues from extensive weathering in high rainfall acidic soils (Kaolinite) 2. Smectites -2:1 clays -swelling sticky clays (Montmorrilonite) 3. Mica Clays 2:1 clays resulting from the weathering of mica minerals (Vermicculite and |
| Oxide (Sesquioxide) Clays | weathered clays - most of silica and alumina has leached and Sesquioxides is what remains |
| Organic Colloids | Humus -the fraction of the soil organic matter remaining after the major portion of added residues have decomposed. |
| CHARACTERISICS OF HUMUS | 1.Dark Colored, 2.Usually Amorphous (can have a positive or negative charge), 3.Has a high Cation Exchange capacity caused by Ionizable H ions |
| Cation exchange | The interchange between a cation in solution and another cation on the surface of any negatively charged particles such as clay or humus. |
| Cation exchange sites | Negatively charged areas on the soil colloid where cations attach themselves |
| How Cation Exchange Occurs | Mass Action and Neutrality equilibrium |
| Mass Action | When a large number of one type of cation is added to the soil solution causing major CEC to occur |
| Neutrality equilibrium | the need for neutral charge in the soil solution and on the colloid causes cation exchange to happen continuously, cations with lower valence exchange easily |
| Cation exchange capacity | the sum total of exchangeable cations that a soil, clay or OM can adsorb at a certain pH. Measured in milligram equivalents per 100 grams of soil. clay or organic colloid or (refer to pg 218 in text for a comparison of Cation Exchange Capacities of differ |
| Low CEC soils have a CEC rate below | 11me/100g |
| Medium to very high CEC soils have a CEC rate | from11-50me/100g |
| Where do the Cations in the soil solution that go through cation exchange come from? | 1. Fertilizer, 2. Soil Minerals, 3. Organic Matter |
| Important cations that attach themselves to soil colloids | Mg2+,Ca2+, K+, NH4+, -Plant Nutrients Al3+, H+ -Acidic cations Na+ |
| % Base saturation | The % of the cation exchange sites filled with exchangeable bases. Most bases are plant nutrients. 80% or more is best for plant growth. |
| Why some cations are held more tightly than others | 1. Valence, 2.Hydrogen bonding |
| Factors which affect the CEC of soils | 1. Number of colloids, 2. Types of colloids, 3. Soil pH |
| Importance of CEC | Effects fertilization practices, Effects liming practices, Effects fertility of unfertilized soils, Effects pesticide application rates, Determines amount of ground water contamination that occurs |
| Anion Exchange -occurs with amorphous colloids (colloids that have a positive or negative charge) | |
| Anions are attracted to | positively charged sites on soil colloids and exchange occurs due to the same reasons for CEC. Anion exchange rates are much lower than cation exchange rates |
| pH | A measure of the acidity or basicity (alkalinity) of a soil. |
| pH Scale | represents the H+ ion concentration in the soil solution |
| Acidic Soils have a high concentration of | H+ (Hydrogen) ions in solution |
| Basic (Alkaline) Soils have a high concentration of | OH- (Hydroxide) ions in solution |
| Optimum pH for plants | Most Plants do best at a ph between 6-6.5 |
| Some plants do better in acidic soils | including Broadleaved Evergreens, |
| Some plants do better in alkaline soils including | Lilacs & some perennials |
| Causes of Soil Acidity | 1. Acidic parent materials. 2. Breakdown of OM, 3.Plant roots releasing H+, 4.Natural acidity of rain (5.6) and acid rain, 5.Plants and leaching removing basic cations from the soil, 6.Clay breaking down which releases Aluminum which reacts with water to |
| Why are NH soils acidic ? | |
| How pH affects plant growth | 1. Affects availability of nutrients, 2. Affects activities of micro and other soil organisms, 3. Affects effectiveness of some chemicals, 4. pH below 4 causes element toxicity, |
| Active vs. Reserve acidity | Active = acidity in the soil solution, Reserve =Acidity on the soil colloids |
| To increase the pH (make the soil more alkaline or basic) | Add Lime- pg 239 text |
| To decrease the pH (make the soil more acidic) | Add sulfur |
| Buffering Capacity | ability of a soil to resist an appreciable pH change or a change in concentration of any ion in solution |
| Organic Matter | Matter derived from living organisms, dead plants and plant parts, dead animals and manures. |
| Humus | Fraction of soil organic matter (OM) remaining after the major portion of added residue has decomposed. Usually dark colored and amorphous. |
| Factors which affect the Organic matter content of soils | Vegetation, Climate, Soil texture, Drainage, Tillage, |
| Benefits of adding Organic Matter to soils | Major source of Nitrogen, Phosphorous and Sulfur in unfertilized soils, Supplies soil aggregate forming cements, Increases CEC of soils, Increases water holding capacity of coarse textured soils, Increases aeration in fine textured soils, Increases buffer |
| Problems with adding Organic Matter to soils | Can host insects and diseases, Can contain toxic substances from other materials, Can have alleleopathic substances in them which are released into the soil, Organic Material that has a high C: N ratio will cause a nitrogen deficiency in the soil unless i |
| Alleleopathy | the direct or indirect harmful effect of one plant on another through the production and liberation of toxic or inhibiting compounds into the environment |
| Carbon to Nitrogen Ratio | the ratio of the weight of carbon to the weight of the total nitrogen in soil or organic matter. |
| Ecological levels of OM in Soils | Usually topsoil contains 3-8% OM, |
| How much OM needs to be added | to change the characteristics of soils -25-50% by volume, to maintain soil characteristics |
| Organic Matter is broken down by soil organisms | Microbes, Macroscopic animals |
| Microbes | Bacteria, Fungi (Breaks down Humus), Nematodes |
| Macroscopic animals | Earthworms, Insects and their relatives, |
| TYPES OF ORGANIC SOIL AMENDMENTS | Plant Material, Animal Byproducts, Compost, Mulches, |
| Plant material | Crop residues, green manuers, Logging and wood residues, Seaweed, Peat moss, Leaf and Yard Waste, Food Waste |
| Crop residues | after crop is harvested its turned into the soil |
| Green Manures | green crops are turned over into the soil to add OM and or nutrients |
| Types of green manuers | Legumes - used to add N to the soil. Ex. - soybeans, vetches, alfalfa, Grasses - quick growing crops with high fiber content usually turned under before they go to seed Ex. - Japanese Millet, Sudan - Sorghum hybrids, Winter Rye |
| Uses of plant material | In rotation, As a cover crop, At the end of the growing season, In between rows, After harvest of a first crop |
| Logging and Wood Residues | Nutrient Composition- (wood chips and sawdust) =. 1% N .04%P and .17%K C\N Ratio - 500: 1 - need to add 25 lbs N for every ton of sawdust or woodchips. |
| Uses of Sawdust | good to break up clay but best to compost |
| Uses of Bark mulch | too expensive for amendment |
| Uses of Woodchips | Construction site and mine spoils until vegetation is established (nitrogen fert) |
| Uses of Seaweed | used as a liquid or dry fertilizer (Seaweed Meal) or as an organic amendment. It has many nutrients in small amounts |
| Uses of Peat Moss | Used to be most common amendment used by horticulturists Used to increase water holding and nutrient holding capacity of soils - Hard to wet once it dries out - Acidic - apply 1 lb dolomitic lime per 4 cu ft of peat to neutralize the pH |
| Leaf and yard waste | best composted |
| Food wastes | best composted |
| Animal byproducts | 1. Animal Manures. 2. Sewage waste |
| Animal Manures | Nutrient composition – see book page 327 |
| Animal Manures Optimum rates | Cow -18-22 tons per acre, For organic farming no more than 90 tons per acre, |
| Animal Manures Methods of application | Applied daily or stored or composted and then applied |
| Animal Manures Methods of Storage | 1. Sewage Lagoons, 2. Piles, 3. Tanks- Liquid manure |
| Animal Manures Application for home gardeners | Not recommended to apply without composting because of disease transmission |
| Sewage Wastes - Liquid | contains up to 5% solids, uses - irrigation water |
| Sewage Wastes – Sludge (Biosolids) | Contains 20% or more solids, average nutrient content 4% N, 2%P, 4%K. Has a high pH (7.5-8.5) |
| Sewage Waste Disposal Choices | 1. Landfill, 2. Incineration, 3. Land Applications |
| Class A Sludge | Material heat treated to reduce pathogen level -Uses are unrestricted |
| Class B Sludge | Material which is not heat treated but is lime stabilized-Used for land application on corn and hay, turf grasses, cemeteries, land reclamation - Use is restricted Concerns include- Heavy metals, other toxins, ground water contamination, human pathogens, |
| Materials, which are commonly composted | Manure-12 ton/acre or less, Sawdust, Biosolids, Yard wastes- grasses, leaves. Excellent organic amendment for landscape situations |
| Mulch | smother weeds absorb water, reduce evaporation, and reduce temp fluctuations include straw, bark, pine needles etc |
| BEST MANAGEMENT PRACTICES | BMP’s |
| ORGANIC FARMING | Organic or Natural Methods are used for farming. Synthetic chemicals such as fertilizers, pesticide, herbicides or growth regulators are not used. In order for produce to be labeled organic it has to be certified. |
| SUSTAINABLE AGRICULTURE (Low Input Sustainable Agriculture) | is an integrated system of plant and animal production practices, which are environmentally sound, economically viable and socially acceptable |
| Soil Erosion | Detachment and movement of soil or rock fragments by water, wind, ice or gravity |
| Geologic erosion | erosion that occurs naturally |
| Accelerated erosion | erosion more rapid than geologic as a result of the influence of humans or animals or natural catastrophes |
| Water erosion | erosion caused by the action of water results from: |
| Types of Water Erosion | Raindrop splash, surface flow erosion, channelized flow erosion |
| Raindrop splash erosion | raindrops strike the soil and break aggregates into fine particles, which can be carried away |
| Surface Flow Erosion | ways that water takes materials downhill on the soil surface (Surface creep and Sheet (laminar) erosion. |
| Channelized Flow Erosion | concentration of water into certain areas resulting in channels in the soil. 1. Rills, 2. Ephemeral Gullies, 3. Gullies |
| Problems that occur due to water erosion | 1. Soil Loss, 2. Loss of nutrients, 3. Loss of pesticides, 4. Increase in time, equipment and management costs, |
| Water Erosion Control Measures - Methods for controlling erosion on 2-5% slopes - Slightly erodible | 1. Grass crops\cover crops –L, 2. Plastic and jute mesh material –L, 3. Stubble Mulches, 4. Conservation tillage, 5. Mulching –L, 6. Contour cultivation, |
| Water Erosion Control Measures Methods for controlling erosion on 5-10% slopes - Moderately erodible | 1. Terraces –L, 2. Sod crops in rotation, 3. Contour Strip cropping, 4. Grass Waterways, 5. Grass crops\cover crops-L, 6. Plastic and jute mesh materials-L, 7. Silt Fences/Erosion socks/Hay bales L, 3. |
| Water Erosion Control Measures Methods for controlling erosion a 10-17% slope-Highly erodible | 1. Terraces-L, 2. Grass \cover crops L, 3. Plastic and jute mesh materials L, 4. Silt Fences/Erosion socks/Hay bales L |
| The Rev Universal Soil Loss Equation | estimates sheet and rill sediment losses from cultivated fields A = R x K x L x S x C x P |
| The Rev Universal Soil Loss Equation – A | Erosion soil loss in tons per acre per year |
| The Rev Universal Soil Loss Equation – R | Rainfall and runoff factor |
| The Rev Universal Soil Loss Equation – K | Soil erodibility factor |
| The Rev Universal Soil Loss Equation – L S | Slope factor |
| The Rev Universal Soil Loss Equation – C | Vegetative cover and management factor |
| The Rev Universal Soil Loss Equation – P | Support practices Factor (Practices used for erosion control) |
| Rainfall Factor – R | Kinetic Energy (falling force X the maximum 30 minute period intensity of fall) Amount of erosion affected by the amount of a given rain and the length of rain |
| Soil Erodibility Factor | Considers how easily a soil can be eroded. Estimated from texture, OM content soil structure and permeability. |
| Slope Length Factor | Considers the slope length- the longer the slope the |
| Slope Steepness Factor | Considers the steepness of the slope. The steeper the slope the more erosion occurs. Doubling the slope more than doubles the |
| Vegetative cover and Management Factor | Considers the type and density of |
| Practice Factor | Considers the type of erosion control measures used |
| T Value | Soil Loss Tolerance Value - the maximum average annual erosion rate consistent with sustaining soils long term productivity and with avoiding severe rills and gullies. |
| Wind Erosion | not a large scale problem in NH due to small field size, many wind breaks and moist soils |
| Wind erosion control | 1. Windbreaks, 2. Shorten Field size, 3. Surface roughness, Soils and Land Use, |
| Ways soil acts as a filter | 1. Physical filter, 2. Chemical filter, 3. Biological filter, |
| Soil pollution is caused by | 1. Solid materials being added faster than they can decompose, 2. Chemicals building up to toxic levels over time, 3. Toxins with long residual life being added to the soil |
| Water pollution is caused by | 1. Erosion of materials including soil into lakes and streams, 2. Materials leaching into the ground water at levels which are toxic to humans and animals, 3. Materials being dumped into sewage systems |
| Types of Pollutants | Fertilizer Nutrients, Lead, Pesticides, Wastewater, Solid wastes, Radionuclides, Soil Sediments |
| Fertilizer Nutrients | Phosphorous-(Eutrophication) and Nitrogen (Ground water contamination, Acid Rain) |
| Wastewater | Industrial liquid wastes, Sewage effluent |
| Solid wastes | 1. Sewage sludge, 2. Animal manure’s, 3. Municipal garbage, 4. Composts and sanitary landfills, 6. Radionuclides, 7. Soil sediments |
| Problems with Soils in Urban areas | 1. They are extremely variable and many times poor quality due to large scale excavation and moving of materials due to burying of debris in urban areas, 2. They are compacted due to heavy vehicle and foot traffic, 3. They can be contaminated lead, road s |
| Brown Fields | severely contaminated land |
| Bioremediation | when microbes or plants are used to reclaim soils |
| Urban Erosion Solutions | 1. Large scale replacement of soil, 2. Adding organic material to the existing soil materials, 3. planning plantings to reduce compaction problems, 4. Aerating existing contaminated sites, 5. Planting plants which will tolerate Urban Conditions, 6. Use er |
Created by:
RoseMellino
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