Biological soil crust (lumpy areas). In the absence of disturbance, succession cannot advance and plants such as grasses cannot establish.
| printer version (loads faster) |
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
bare ground - Exposed soil that has no plant growing on it and no litter mulching it. While soil exposed to sun and wind suffers the most damage, bare soil under plants can also be a problem, particularly if water can run across the surface and cause sheet erosion.
Related pages: "Landscape brittleness and productivity", "How to grow new topsoil," "Grazing management for healthy soils"
basal area or basal cover - The area of soil surface covered by the stem or stems of a rangeland plant, usually measured 1 inch (25 mm) above the soil. A bushy bunchgrass may cover a wide area with spreading leaves, yet have a small basal area.
baseline - A set of data used for comparison. Monitoring land condition starts with establishing a baseline of the land's current condition. By comparing this data to the results of subsequent monitoring, you learn whether you are moving toward or away from the outcome you want, and how fast.
bell curve - normal curve
biodiversity - Biological diversity in an environment as indicated by:
Related terms: community dynamics desertification, succession
Related pages: "Desertification"
biodiversity loss Loss of biomass and biological diversity in an environment. When biodiversity declines severely, we call the result desertification.
Related terms: biodiversity, desertification, succession
Related pages: "Desertification"
biological crust - A hard soil crust dominated by a plant community of algae, lichens, or mosses. See biological soil crust.
biological productivity - The amount of sunlight energy an environment is able to convert into biomass. Often measured as tons of agricultural crop per unit of land area, or amount of harvestable forage. More fundamentally, it is the ability of an area to grow vegetation that sustains game, livestock, or people.
Related terms: solar capture, brittleness-productivity scale
Related pages: "Landscape brittleness and productivity"
|
Biological soil crust (lumpy areas). In the absence of disturbance, succession cannot advance and plants such as grasses cannot establish.
|
biological soil crust - (Also mature capping, biological crust, cryptogamic crust, algal crust.) A hard soil crust dominated by a plant community of algae, lichens, or mosses. Soil crusts cause water to run off soil rather than soaking in, exclude air, and prevent seeds from germinating successfully.
Characteristic of long-term rest from disturbance in brittle areas, biological soil crusts usually indicate severe ecosystem damage that prevents succession from advancing further. On level ground, soil crusts can endure for centuries.
Biological soil crusts are natural in undisturbed brittle areas -- on cliffs and in areas were grazing animals cannot go. Unfortunately, some people think these crusts are beneficial anywhere they occur, and should be protected from disturbances such as livestock trampling. This guarantees that succession will not advance and damaged land will not heal.
Once trampled, crusts often become home for cheatgrass and other weedy plants. This simply means succession has started to rise. If well-managed grazing continues, these weeds soon give way to higher-succession perennial forage plants.
Related terms: soil crust, physical soil crust, capping, rest
Related pages: "Soil crust basics", "Environmental restoration", "Desertification"
biomass - The mass or volume of life, for instance in a given area of pasture or volume of soil. Declining biomass is one of the first signs of biodiversity loss.
biome - A major type of ecological community, such as tropical rain forest, grassland, or desert.
Related terms: brittleness-productivity scale
Related pages: "Landscape brittleness and productivity"
BLM - U.S. Bureau of Land Management.
brittle - An environment characterized by unreliable and irregular precipitation, and slow decay. Rainfall may be high or low, but there is always a dry season. Long-term rest from disturbances such as grazing and fire causes brittle areas to lose biodiversity and desertify.
Related terms: brittleness, nonbrittle, semi-brittle, brittleness-productivity scale
Related pages: "Brittleness" (articles)
brittleness - A way of categorizing how ecosystem processes function in landscapes. In nonbrittle landscapes, moisture is constant throughout the year. Decay happens rapidly, and long-term rest from disturbances such as fire and grazing heals land. Brittle areas may have high or low rainfall, but they always have a dry season. Decay happens slowly, and long-term rest causes desertification. Diagram.
Related terms: brittle, nonbrittle, semi-brittle, brittleness-productivity scale
Related pages: "Brittleness"
brittleness scale - Allan Savory's original measure of brittleness:
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | ||||||||||
| very nonbrittle | nonbrittle | semi-brittle | brittle | very brittle | |||||||||||||||
Compare brittleness-productivity scale.
Related terms: brittle, nonbrittle, semi-brittle
Related pages: "Brittleness"
brittleness-productivity scale - A new measure of brittleness that also distinguishes environments with different levels of biological productivity. Based on Allan Savory's brittleness scale, it was developed by Jim Howell. Article.
| Non-brittle | Semi-brittle | Brittle | |
|---|---|---|---|
| High annual production | Tropical rainforests | Subtropical and temperate tall-grass prairies | High-rainfall tropical savannas |
| Temperate rainforests | Mid-rainfall tropical savannas | ||
| Medium annual production | Mild temperate forests | Mild and cold temperate mid-grass prairies | Low-rainfall tropical savannas |
| Cold temperate forests | Mild and cold temperate steppe grasslands and shrublands | ||
| Low annual production | Subarctic coniferous forests | Tundra and alpine grasslands | True deserts -- tropical, mild, cold, arctic |
Related terms: brittleness, brittle, semi-brittle, nonbrittle
Related pages: "Landscape brittleness and productivity", "Brittleness" (articles)
browse - Noun: Tender shoots, twigs, and leaves of trees and shrubs used as food by animals. Verb: To eat browse.
Related terms: browser, grazer, grazing
browser - A herbivore that subsists mostly on browse. Compare grazer.
bunchgrass - Any grass that tends to grow in distinct, separated clumps
Bureau of Land Management - An organization within the U.S. Department of the Interior responsible for managing land and natural resources. The BLM administers vast areas of publicly owned grazing land in the western U.S.A.
Related terms: allotment
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Suggestions for terms or definitions? Email us (opens web form).
Updated 1 November 2005
URL: managingwholes.com/glossary/b.htm