1. Rangeland principles, REM 151
adifferentbrian (Flickr)
(Lauren Kerns (Flickr)
Climate on Rangelands
J. Peterson
J. Peterson
J. Schmidt (
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time (Wikipedia)
Rangeland principles, REM 151

2. Climate on Rangelands
Climate = Long-term patterns of temperature & precipitation
Weather = short-term variation in temp., precip. wind, humidity, etc.
J. Schmidt (
J. Peterson
Jim Peaco (

3. How does climate affect
vegetation patterns?
Affects plant biomass (amount of vegetation)
Drives photosynthesis (water + light + CO2 = energy)
Determines growing periods (frost-free period)

4. How does climate affect
vegetation patterns?
Affects types of plants that will grow:
Trees need more water than shrubs, forbs & grasses.
Some plants like it hot & some like it cold.
Depends on plant physiology.
Christian Ostrosky (Flickr)
Christian Ostrosky (Flickr)
Daniel Case (Flickr)
Desert vs. tropical vs. tundra…all very different ecosystems in reference to the amount of precipitation and temperature cycles. Differences can be seen in diversity of vegetation, size of vegetation and physiology of vegetation.
VS.
VS.

5. How does climate affect
vegetation patterns?
Gelisol
Oxisol
Mollisol
Influences soils texture & structure.
Precipitation and temperature
Chemical vs. Physical weathering
Water can wash away material, freezing/thawing cycles can break materials down, water is a medium for organic acids which can break down primary materials into secondary materials
Temp influences the rate of weathering. The higher the temp the faster/more chemical process that can go on. Under freezing temps very little chemical weathering takes place, however, physical weathering from freeze/thaw cycles can begin.
Gelisol – Tundra soil. cold temps and permafrost hinder water movement and chemical weathering. The result is slow sub-surface soil development
Oxisol – Tropical soil. high temps and precip create high rates of chemical and physical weathering moving many of the nutrients out of these soils
Mollisol – Temperate soil/prairie soil. moderate temperatures and precipitation amounts that allow soil development to occur at a faster rate than a gelisol, but not like an oxisol. Many of the nutrients are retained in these soils.
There are many other factors that differentiate these soil types. Climate is only one of the 5 soil forming factors.

6. Community of organisms & abiotic environment
Ecosystems
Community of organisms & abiotic environment
NOA.gov
VS.
Tupulak (Flickr)
Christian Ostrosky (Flickr)
Ecosystems are generally divided into two major groups: Aquatic vs. terrestrial.
Terrestrial ecosystems can vary drastically in makeup or size. It depends on how finely we wish to divide up the communities.
A desert ecosystem and a tropical ecosystem are vastly different on many levels, but if we were to look closer at both systems we could divide them up even farther depending on differences is soil type, topography, primary vegetation cover or animal communities. We do not need to worry about aquatic ecosystems for this class.
VS.
Jeff Shewan (flickr)

7. Biome Largest terrestrial ecosystem that is easily recognizable.
Biomes are the largest recognizable units, they are very large ecosystems recognized by predominant vegetation & animal communities (adaptations of organisms to that particular environment).
Tiaga = northern Forests
Desert and Desert-Scrub are often combined to create 9 instead of 10 biomes.

8. What creates different biomes?
Precipitation
Temperature
Soils
Topography
Rangelands evolved where precip was insufficient for forests, but too much for barren deserts
These are RANGELANDS

9. ↓ ↓ ↓ Fill in the Blank ↓ ↓ ↓
Cold Desert
Deciduous Forest
Tundra (Polar Grasslands)
Tropical Rain Forest
Precipitation
Tropical Desert
Northern Coniferous Forest
Temperate Grassland
Major biomes – based on graphic depiction by G. Tyler Miller, Resource Conservation and Management. Belmont California Wadsworth Publishing Co.
Temperate Desert
Savanna (Tropical Grassland)
Temperature

10. Precipitation Temperature
Northern Coniferous Forest
Forest
Deciduous Forest
Tropical Rain Forest
Tundra (Polar Grasslands)
Temperate Grassland
Precipitation
Grasslands
Savanna (Tropical Grassland)
Major biomes – based on graphic depiction by G. Tyler Miller, Resource Conservation and Management. Belmont California Wadsworth Publishing Co.
Tropical Desert
Desert
Cold Desert
Temperate Desert
Temperature

11. Hadley Cell Effect
Atmospheric circulation patterns between circulation between the equator and 30 latitude.
Hadley Cell (N)
Hadley Cell (S)
Altitude and latitude are important: Hadley cells
Warm air wants to rise, and cold air wants to fall. Cold air that has dropped near the 30° (N or S) latitude, and circulated along the surface of the earth warms and acquires moisture (as it heads N or S). Then at the equator it rises, where the moisture it acquired as it traveled along the surface of the earth condenses as it cooled, and produces rain. It then circulates back, high above the surface of the earth, and drops to the surface of the earth where it warms and acquires more moisture. The Sahara, Namib and Kalahari deserts in Africa are located in places where warm air has fallen, and travels across the surface of the earth and gathering moisture. The Congo is located near the equator, where the air from the Namib, Kalahari and Sahara meet, full of moisture, and begin to rise and precipitate.
This effect creates bands of moist or dry zones around the globe.

12. Equator 30° Continental Land Effects
Lands around large bodies of water tend to have climates with:
Mild temperatures
Abundant precipitation (moist or mesic)
Centers of continents are often:
Extreme temperature variation (summer to winter)
Dry

13. Topographic Effects Orographic Barriers
From
Orographic Barriers
Mountains can create Orographic Barriers with Rain Shadows on the leeward side

14. Rangelands of the World
Map created by Eva Strand, Karen Launchbaugh, and Christopher Bernau of the University of Idaho based on a global database created by the World Wildlife Fund
Do we remember what the definition of a rangeland is? Rangelands are shrublands, grasslands, deserts, woodlands, and open forest.
In the figure above it would appear “grey” indicates non-rangeland, and then if we remember the “what is rangeland” presentation from class, all deserts are considered rangeland with the exception of barren deserts. So, that last brown color titled “barrenland” would not be considered rangeland.

15. Mean annual precip.

16. There are several ways to categorize climate. This is one of them.
I’m assuming this figure is using a combination of mean annual precip and temp.

17. Variation in Precipitation
Effective precipitation = when precipitation is Most usable by plants.
One of the greatest challenges of managing rangelands is dealing with these year-to-year variations in precipitation. The variation from year to year is great, and if we look the bulk of our precipitation is falling outside of April-June.
Min Precip = (1989) 6.6 inches Max Precip = (1982) 23.6 inches Average = 14.9 inches

18. Fifty years of change in a Shadscale Stand in Idaho
Lee A. Sharp, Ken Sanders & Neil Rimbey
The following rangeland photo journal charts the changes that have occurred in a shadscale (Atriplex confertifolia) stand in southern Idaho starting in1951.
Photos of the site have been taken annually since 1955, but the selected photos show the dynamic nature of the site.
To emphasize the point in variation from year to year…

19. 1951 3.5” Apr-Jun 12.8” Annual Precipitation
The shadscale stand in 1951, the first year of the study, appeared very healthy. Precipitation was near average during the spring. Shadscale is the green-leaved shrub and the grass in the foreground is squirreltail grass.
April to June is the timeframe for effective precipitation.
inches
50-yr avg
50-yr avg

20. 1955 3.5” Apr-Jun 12.8” Annual Precipitation
After a very dry year in 1954 and a dry spring in 1955, the shadscale had very little current year production. The squirreltail grass, a short-lived perennial, was starting to be replaced with halogeton.
An average year following a poor year
inches
50-yr avg
50-yr avg

21. 1958 2.5” Apr-Jun 12.0” Annual Precipitation
The scale insect was beginning to kill branches of shadscale. Squirreltail grass had little production because of the dry spring. Prickley pear cactus, Sandberg’s bluegrass (Poa sandbergii), and globe mallow (Sphaeralcea grossularifolia) were other perennial plants present in the stand. Halogeton and one other annual plant species were also present.
An average year with considerably poor precip values for the months of April-June
inches
50-yr avg
50-yr avg

22. 1963 7.1” Apr-Jun 22” Annual Precipitation
Precipitation was much above normal in the spring of A number of shadscale seedlings in 1962 gave rise to the shadscale recovery in this year. Note the globe mallow (orange flowered plant) throughout the stand. Squirrel-tail grass was also making a comeback.
Above average year with above average precip values for the months of April-June. We can see this is following several very poor precip years.
inches
50-yr avg
50-yr avg

23. 1964 8.8” Apr-Jun 24” Annual Precipitation
Spring precipitation was even greater than in 1963 (three times the average). This was the best globe mallow expression in the 50 years of the study. Squirreltail grass was also very productive.
Back to back productive years with above annual precip
inches
50-yr avg
50-yr avg

24. 2005 3.8” Apr-Jun 19” Annual Precipitation
This is what the roughly how the site looks currently. The community has been shifted over to a cheatgrass community and is at high risk to wildfire. What are some management options for the site?
Our perennial shrub and grass community appears to be nothing like what is used to be. The site has been taken over by annual forbs and grasses.
Fire would kill all the last of our shrubs…
Grazing might single out the last of our perennial grasses…
inches
50-yr avg
50-yr avg

25. ” Apr-Jun ” Annual
A cold dry winter took a toll on the cheatgrass on this site. Now the site looks much like it did in the past. Note the abundance of shad scale. Perennial grasses are still a component. Though annual grasses and forbs are nearly absent.

26. Geographic Climate Regions
Mediterranean
Pacific Northwest
Great Basin
Southwest Deserts
Great Plains
Mountains
Figure by K. Launchbaugh
Geographic Climate Regions
This is Karen’s approximation of climatic regions that relate to vegetation patterns

27. Grassland & Savannas Deserts & Semideserts Mediterranean
Presentation (ppt.)
Grassland & Savannas
Deserts & Semideserts
Mediterranean
Deserts & Semideserts
There are

28. Rangeland principles, REM 151
adifferentbrian (Flickr)
(Lauren Kerns (Flickr)
Climate on Rangelands
J. Peterson
J. Peterson
J. Schmidt (
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time (Wikipedia)
Rangeland principles, REM 151