Across
- 3. A system that releases more carbon than it absorbs.
- 7. Soil made up mostly of intermediate-sized particles, 0.002–0.05 mm in diameter.
- 9. matter Substances derived from living organisms, such as plant debris, faeces, or other carbon-based compounds.
- 11. A symbiotic relationship where both species benefit.
- 13. A state of very low biological activity, as in inactive seeds.
- 14. Movement of water into the soil from the surface.
- 15. The upper organic layer of soil rich in decomposing plant material.
- 16. Produced by or originating from human action.
- 22. Breakdown of organic molecules by living cells to release energy; can be aerobic or anaerobic.
- 24. Diffusion of gases into and out of soil, often increased by ploughing or burrowing animals.
- 30. Chemical reactions between rock minerals and water, oxygen, or acids.
- 31. Conversion of organic matter (humus) into mineral nutrients usable by plants.
- 32. A space between soil particles where air or water may be found.
- 35. A natural store of viable but dormant seeds within the soil.
- 37. A clump of soil formed when mineral particles stick together.
- 38. The subsoil, where materials like clay and minerals accumulate from above.
- 39. Thin, branching, thread-like structures of fungi.
- 40. Fungi forming mutualistic relationships with plant roots, exchanging minerals and water for sugars.
- 42. A cycle involving the movement and transformation of chemical elements through Earth’s systems.
- 44. The vertical section of soil showing all horizons and their characteristics.
- 46. An animal that eats detritus, breaking it into smaller pieces.
- 47. Movement of water through the soil layers.
- 48. A substance required by plants in small quantities, such as iron or zinc.
Down
- 1. A substance required by plants in large quantities, e.g., nitrogen, phosphorus, potassium.
- 2. Permanently frozen layer of soil that stores large amounts of organic carbon.
- 4. The process of salt accumulation in soil, usually due to excessive irrigation.
- 5. Soil made up of particles of various sizes and containing a significant percentage of organic matter.
- 6. Breakdown of rock by organisms such as lichens or plant roots.
- 8. matter Substances not derived from living organisms, usually from bedrock, air, or water.
- 10. A fluid secreted by a living organism, such as sugars or amino acids from plant roots.
- 12. The topsoil or mixed layer beneath the O horizon, rich in minerals and humus.
- 13. Biological breakdown of organic material into simpler substances.
- 17. Fully decomposed organic matter forming a dark, sticky material coating mineral particles.
- 18. Soil made up mostly of very fine particles, less than 0.002 mm in diameter.
- 19. The process of rocks breaking into smaller fragments by water, dissolved substances, organisms, or temperature changes.
- 20. Physical breakdown of rocks by freezing, thawing, heating, or abrasion.
- 21. Fine, wind-blown deposits of silt forming fertile soils in some regions.
- 23. A microorganism that breaks down organic matter by secreting enzymes and absorbing the products.
- 25. The rock that is broken down to provide the mineral components of a particular soil.
- 26. Partially decomposed organic matter.
- 27. The addition of harmful substances or pollutants to soil, intentionally or accidentally.
- 28. A symbiotic relationship where one species benefits and the other is harmed.
- 29. Involving or requiring oxygen; produces carbon dioxide.
- 30. A system that absorbs more carbon than it releases.
- 33. Occurring without oxygen; produces methane.
- 34. The lowest layer of soil, composed mainly of weathered parent material.
- 36. Downward movement of dissolved substances through soil with percolating water.
- 41. Partially decomposed organic matter accumulating in waterlogged soils.
- 43. Stony or rocky particles in soil larger than 2.0 mm in diameter.
- 44. Soil made up mostly of relatively large particles, from 0.05 to 2.0 mm in diameter.
- 45. Movement of broken-down rock particles from one place to another by agents like wind or water.