Across
- 1. An element or compound that organisms consume and require for survival.
- 4. The total biomass that heterotrophs generate by consuming autotrophs.
- 6. A network of relationships among a group of parts, elements, or components that interact with and influence one another through the exchange of energy, matter, and/or information.
- 8. The release of water vapor by plants through their leaves.
- 10. Bacteria that live independently in the soil or water, or those that form mutualistic relationships with many types of plants and provide nutrients to the plants by converting gaseous nitrogen to a usable form.
- 11. Water that condenses out of the atmosphere and falls to Earth in droplets or crystals.
- 14. The sum total of all the planet’s living organisms and the nonliving portions of the environment with which they interact.
- 16. The movement of nutrients among reservoirs in a nutrient cycle.
- 17. The practice of constructing and testing models that aim to explain and predict how ecological systems function.
- 19. A major nutrient cycle consisting of the routes that carbon atoms take through the nested networks of environmental systems.
- 20. An artificial water body behind a dam that stores water for human use.
- 23. Net primary production is the energy or biomass available for consumption by heterotrophs.
- 24. A transitional zone where ecosystems meet.
- 26. The conversion of solar energy to the energy of chemical bonds in sugars during photosynthesis, performed by autotrophs.
- 29. A simplified representation of a complex natural process, designed by scientists to help understand how the process occurs and to make predictions.
- 33. The state reached when processes within a system are moving in opposing directions at equivalent rates so that their effects balance out.
- 35. information systems Computer software that takes multiple types of data (for instance, on geology, hydrology, vegetation, animal species, and human development) and overlays them on a common set of geographic coordinates.
- 36. In landscape ecology, a spatial configuration of patches arrayed across a landscape.
- 39. The process of nutrient enrichment, increased production of organic matter, and subsequent ecosystem degradation in a water body.
- 42. A feedback loop in which output of one type acts as input that moves the system in the same direction.
- 43. primary production
- 45. An assemblage of all organisms and nonliving entities that occur and interact in a particular area at the same time.
- 49. Water held in aquifers underground.
- 51. A major nutrient cycle consisting of the routes that nitrogen atoms take through the nested networks of environmental systems.
- 52. Elements and compounds required in relatively large amounts by organisms.
- 54. A feedback loop in which output of one type acts as input that moves the system in the opposite direction.
- 55. A process to synthesize ammonia on an industrial scale. Developed by German chemists Fritz Haber and Carl Bosch, the process has enabled humans to double the natural rate of nitrogen fixation on Earth and thereby increase agricultural productivity, but it has also dramatically altered the nitrogen cycle.
- 56. A major nutrient cycle consisting of the routes that phosphorus atoms take through the nested networks of environmental systems.
Down
- 1. The rate at which net primary production is produced.
- 2. The layer of gases surrounding planet Earth.
- 3. All water—salt or fresh, liquid, ice, or vapor—in surface bodies, underground, and in the atmosphere.
- 5. property A characteristic that is not evident in a system’s components.
- 7. In landscape ecology, spatial areas within a landscape.
- 9. The conversion by bacteria of ammonium ions (NH4+) first into nitrite ions (NO2–) and then into nitrate ions (NO3–).
- 12. An underground water reservoir.
- 13. Bacteria that convert the nitrates in soil or water to gaseous nitrogen and release it back into the atmosphere.
- 15. In environmental science, a step in a process that limits the progress of the overall process.
- 18. In a nutrient cycle, a reservoir that accepts more nutrients than it releases.
- 21. The entire area of land from which water drains into a given river.
- 22. The flow of water—in liquid, gaseous, and solid forms—through our biotic and abiotic environment.
- 25. The study of how landscape structure affects the abundance, distribution, and interaction of organisms.
- 27. The condition of extremely low dissolved oxygen concentrations in a body of water.
- 28. A scientific discipline devoted to understanding the factors, forces, and processes that influence the loss, protection, and restoration of biodiversity within and among ecosystems.
- 30. The comprehensive set of cyclical pathways by which a given nutrient moves through the environment.
- 31. The process by which inert nitrogen gas combines with hydrogen to form ammonium ions (NH4+), which are chemically and biologically active and can be taken up by plants.
- 32. An abundant element in the lithosphere, a key element in macromolecules, and a crucial plant nutrient.
- 34. In a nutrient cycle, a reservoir that releases more nutrients than it accepts.
- 37. The rate at which plants convert solar energy (sunlight) to biomass.
- 38. Elements and compounds required in relatively small amounts by organisms.
- 40. An area where a river flows into the ocean, mixing fresh water with saltwater.
- 41. The conversion of a substance from a liquid to a gaseous form.
- 44. A circular process in which a system’s output serves as input to that same system.
- 46. A network of subpopulations, most of whose members stay within their respective landscape patches, but some of whom move among patches or mate with members of other patches.
- 47. The upper limit of groundwater held in an aquifer.
- 48. The geographic area that produces air pollutants likely to end up in a waterway.
- 50. The tendency of a system to maintain constant or stable internal conditions.
- 53. The water from precipitation that flows into streams, rivers, lakes, and ponds, and (in many cases) eventually to the ocean.