Soil health overview
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The document discusses the importance of soil health and its relationship to soil function. It explains that soil serves several important functions like supporting plant growth, regulating water, recycling nutrients, providing habitat, and supporting construction. Soil health refers to the soil's ability to carry out these functions. The document then discusses the components of soil, including solids like sand, silt and clay, pore space, organic matter, and the role of aggregation and structure. It notes several characteristics of healthy soil and how intensive agriculture can damage soil health through tillage, lack of diversity and cover crops, and overuse of chemicals. This can trigger a downward spiral of loss of organic matter, structure, and function over time. Strategies to improve
Soil health overview
- 1. Soil Health ↔ Soil Function Kitty O’Neil, Ph.D. Cornell Cooperative Extension, NNY Northern NY Field Crops Team
- 2. Soil Health ↔ Soil Function • At the end of the hour… – Understand the functions of soil and their dependence on soil composition and structure – Explain to someone what soil is made of , how it’s organized and how it behaves – Think of some ideas how you might preserve or improve your soil health Northern NY Field Crops Team
- 3. Why do we care about soil? ? Northern NY Field Crops Team
- 4. Why do we care about soil? • Soil resources were and are a central factor in shaping human history and development. • Survival of humans and animals is dependent on light, water, air and soil. • Civilizations have crashed as a result of degraded soil. • Good, productive soil is a basic human need. Northern NY Field Crops Team
- 5. Why do we care about soil? • “Man—despite his artistic pretensions, his sophistication, and his many accomplishments—owes his existence to a six-inch layer of topsoil and the fact that it rains.” - Author unknown Northern NY Field Crops Team
- 6. What does soil DO? OK, so soil is important. Why? What does soil actually DO? ? Northern NY Field Crops Team
- 7. What does soil DO? 1. Soil serves as a natural medium for the growth of plants, 2. regulates and purifies water, 3. recycles organic wastes and nutrients, 4. provides habitat for soil organisms, and 5. serves as physical support for building and construction. = Soil functions Northern NY Field Crops Team
- 8. What does soil DO? 1. Soil serves as a natural medium for the growth of plants, 2. regulates and purifies water, 3. recycles organic wastes and nutrients, 4. provides habitat for soil organisms, and 5. serves as physical support for building and construction. Soil health = soil’s capacity to function Northern NY Field Crops Team
- 9. What is ‘soil?’ ? Northern NY Field Crops Team
- 10. Soil = solids + pore space Composition of typical soil, by volume Sand Silt Clay From Univ. of Massachusetts Extension Vegetable Program, Soil Basics, part I Northern NY Field Crops Team
- 11. Organic matter • Wide range of organic materials – Living organisms • Plants, roots • Insects, nematodes • Fungi, bacteria – Non-living OM, products of decomposition of living things • Continuously decomposed, new compounds synthesized by other microorganisms • Holds mineral particles together to form aggregates Northern NY Field Crops Team
- 12. Pore space = air + water • Air space provides gas exchange to organisms and plant roots • Water is needed by plants and organisms • Soil water also contains dissolved mineral compounds & nutrients needed by plants and organisms Northern NY Field Crops Team
- 13. Soil Aggregation, Structure Northern NY Field Crops Team
- 14. Soil Aggregation, Structure Northern NY Field Crops Team
- 15. Soil Aggregation, Structure Northern NY Field Crops Team
- 16. Soil Structure → Water Infiltration, Erosion Resistance More storage Less storage Northern NY Field Crops Team
- 17. Characteristics of healthy, wellfunctioning soils • Good tilth = desirable combination of particle size, moisture content, aeration, water infiltration, drainage • Sufficient nutrient content, not excessive • Good, deep rooting depth • Sufficient water storage and drainage • Free from harmful toxins • Plenty of active, beneficial organisms • Few pathogenic, parasitic organisms • Few weeds • Resilient, able to resist degradation, erosion; recovers well from disturbances Northern NY Field Crops Team
- 18. Agriculture can damage soil health • • • • • Frequent, intense tillage Plant monocultures, loss of diversity Bare soil Heavy fertilizer/chemical use Heavy machinery traffic → Loss of soil structure → more runoff → Loss of soil through erosion → Loss of soil organic matter → Fewer, less active beneficial soil organisms Northern NY Field Crops Team
- 19. Downward Spiral of Damage… Intensive tillage, erosion, insufficient plant residues Loss of SOM, compaction Loss of aggregate structure Compacted, crusty soil surface Reduced infiltration, wind and water erosion Loss of more SOM, topsoil, nutrients Poor drainage, ponding, insufficient rooting depth Fewer beneficial soil organisms, more pathogens Crop yields decline Northern NY Field Crops Team
- 20. Downward Spiral… Reduced Soil Health ↓ Reduced Soil Function Northern NY Field Crops Team
- 21. Compacted Soil Surface Northern NY Field Crops Team
- 22. Water Erosion Northern NY Field Crops Team
- 23. Wind erosion in NNY this winter Northern NY Field Crops Team
- 24. So, how to minimize the damage? 1. Reduce frequency and intensity of tillage operations, compaction – No-till, strip-till, ridge-till, mulch-till, vertical-till – All designed to disturb as little soil as possible 2. Increase organic matter inputs – Cover crops, manure, compost, plant residues 3. Vegetative plant cover all year – No bare soil, spring tillage – Winter cover crops, leave plant residues Northern NY Field Crops Team
- 25. So, how to minimize the damage? 4. Reduce compaction, field traffic 5. Crop rotation, perennials – Long rotations 6. Manage pests and nutrients efficiently – Test and monitor, apply only when needed at the right time and place for optimal effect Improvement takes time. Northern NY Field Crops Team
- 26. Soil Health ↔ Soil Function • How did we do? – Understand the functions of soil and their dependence on soil composition and structure – Explain to someone what soil structure is and how it drives healthy soil function – Think of some ideas how you might preserve or improve your soil health Northern NY Field Crops Team
- 27. Questions? Northern NY Field Crops Team