What we will coverTheory What is soil ? Understanding your soil Soil Food webPractical - Observations Soil sampling and analysis
What is Soil A mixture of mineral matter, organic matter, water,and air A thriving ecosystem Very variable from place to place and foreverundergoing change. The soil is dynamic. Under appreciated.
Mineral Inputs-RocksRocks break down overtime and by doing so contributethe mineral content to the soil . Physical weathering-Frost shatteringRoot growth
Mineral Inputs-Rocks Chemical weatheringNot only causes rocks to disintegrate, also changes thechemical nature of the mineralsWater reactionsRoot SecretionsSoil Organisms
Organic Inputs Primary Colonisers
Transformation – Minerals The disintegrated rock takes the form of three main observable particlesizes SAND – SILT – CLAY
Transformation –Organic Matter In healthy soil organic material inputs decompose and transform into Humusand minerals. HumusPersists in the soil providing foods and protective substances for plantsHolds incredible volume of waterCreates good soil structureCreates ideal environment for soil life
Texture Texture refers to the proportion of sand-silt and clay in the soil and can giveus a read on how our soil will interact with vegetation and soil life. Sand: Fast Drainage – easy to work – Low fertility – warms quickly Silt: Med fertility – easy to work – prone to crusting – poor structure – drains well Clay: High Fertility- hard to work- poor drainage- prone to compaction Loam: Equal proportions of sand-silt and clay. The ideal texture
Structure Structure refers to how the sand silt clay and SOM are bonded together intoaggregates. A diversity of aggregates provides a diversity of pore spacewhich is the ideal situation for plant growth and provides habitat for soilorganisms
Organic Matter - Soil Food Web
Organic Matter - Soil Life
Organic Matter – Benefits of Healthy Soil Food Web Increased Nutrient retention Improved crop quality Pest and disease suppression Improved soil structure Decomposition of Toxic chemicals A cleaner environment
Soil Profile Most of the fertility is present in the top 10cms (The Rhizosphere) Most of the soil life inhabits this horizon Most of the crop plants we grow feed from this horizon
Other Soil Factors pH Nutrient Storage Water Relations
Essential points A diversity of soil life creates healthy soil We are aiming to grow soil and the soil will take care of theplants Organic matter is the most important ingredient for thefunctioning of healthy soil therefore healthy plants By adding organic matter we feed the soil and keep it in goodcondition to take care of the plants Only when fresh organic matter has been mineralised by thesoil life is it available to plants.