Remote Sensing Student Project
Emporia State University
Created 04 December 2001
(Click on Photos to see enlarged view)
Cattle grazing in the Flint Hills of Kansas is an important agricultural commodity. The Flint Hills region is the largest contiguous area of tallgrass prairie left in the world. The tallgrass prairie is characteristic of having sufficient moisture to grow deep-rooted mid and tall perennial grasses. These perennial grasses provide sufficient forage to allow for excellent livestock gains. Much of the Flint Hills are stocked with cow-calf pairs or steers. Grazing can occur year-round with supplemental forage given during the winter months. Other livestock management regimes begin grazing in mid to late Spring and ending in late Summer. The cattle are then shipped to feedlots to fatten the cattle before slaughter. Cattle grazed on the grasses and legumes of the Flint Hills provides a large amount of beef eaten by people throughout the world.
Cattle in the Flint Hills in November, 2001. These cattle will need to be fed additional supplement because the dormant warm-season grass is not nutritious enough for the cattle to gain weight throughout the winter.
Prairie Hay is commonly used as the winter supplement for cattle in the Flint Hills. The prairie hay is taken from meadows in July and August when the grass has sufficient nutritional content, and then fed to the cattle throughout the winter.
Cattle grazing in the Flint Hills in July, 2001. Nearly every portion of the Flint Hills has cattle grazing on it at this time of year.
Large herbivores have evolved to be an influential aspect of the tallgrass prairie. Bison were the dominant grazer in this region when European settlers arrived to the new world. It did not take long before the bison were replaced by the domestic cow. Cattle and bison are beneficial to the prairie by reducing woody vegetation and stimulating forb growth. Forbs are an important nutritional source for cattle and also provide habitat and food for many types of wildlife. However, as ranchers strive to produce the highest returns, overgrazing can be a significant problem. Overgrazing reduces the health of the prairie and poses a problem to surrounding water sources by increasing soil erosion.
Severe erosion caused by cattle traveling along a fence line and destroying the grass in that area. The cattle trails channel the water causing it to erode the soil.
Erosion caused by heavy grazing in an area that has a significant slope. Grazing reduces plant material that stabilizes the soil and as a result, the soil is carried away to streams and ponds.
The severity of forage removal by cattle is dependent on many things. Probably the most important is the duration of time the cattle are able to remove the forage. Almost equally important is the soil type and a function of the topography of the landscape. Poorer soils will not be capable of sustaining the forage removal as well as higher quality soils. Additionally, cattle have a tendency to avoid steep slopes as they are grazing. Therefore, flat areas in the pasture tend to be more heavily grazed than does areas with a steep slope.
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Landsat 7 TM image taken in July, 2000. The image was acquired from the EROS Data Center by Kansas Department of Wildlife and Parks (KDWP) and I recieved the images from KDWP. The boundary of the Preserve was masked to remove the portion of the image not controlled by the National Park Trust. Observe the amount of bare ground, depicted by the light browns, in the image. July, 2000 was in the middle of a dry season and you can see that the grazing affects were quite large. The area in the top of the photo is especially heavily affected, whereas the areas in the lower right of the image were not as affected. The white areas in the photo that appear to follow the contours are limestone outcrops. Landsat TM Bands 1,2,7.
Digital certified soil survey of the study area was acquired from the State of Kansas Data Access and Support Center (DASC). The top portion of the image was unable to be acquired due to data access problems. Soil types can be compared to Landsat TM image to see which soils are more susceptible to heavy grazing.
Analysis of Landsat TM image and Digital Soil Survey
This is a hillshading image created in ArcView. It takes the slope, aspect and elevation of an image and calculates a 3-D representation of the landscape. The image will allow you to see the strong sloping areas and which direction they are facing. Topography can be compared with the Landsat TM image to see any relationship. The digital topography images were acquired from DASC.
Analysis of Landsat TM image and Hillshading Image
Soil types commonly change with changing topography in a landscape. This is an important concept because the grazing patterns are not likely to be completely dependent on soil type or topography alone.
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With the advent of more advanced technology in remote sensing, applications to fit all occupations are surfacing. Using remote sensing and GIS to advance grazing science will improve efficiency and productivity within this commerce. Understanding the methods used to analyze the grazing distribution on the Tallgrass Prairie Preserve is as simple as knowing how to use one of the many GIS software programs available. The Landsat TM image used in this analysis is useful alone for determining grazing patterns in a pasture. Together with the digital files I used or any other coverage that has an effect on grazing patterns (water bodies, fences, etc.) will be useful in determining appropriate grazing management practices.
The National Park Service, Tallgrass Prairie National Preserve, World Wide Web homepage URL: http://www.nps.gov/tapr/home.htm
Owensby, C.E. 1997. Introduction to Range Management. Department of Agronomy, Kansas State University, Manhattan, KS.
United States Geological Survey, EROS Data Center, World Wide Web homepage URL: http://edc.usgs.gov/
State of Kansas, Data Access & Support Center, World Wide Web homepage URL: http://gisdasc.kgs.ukans.edu/
All photos were taken by the author and should not be used without permission. Questions and comments about this webpage can be sent to email@example.com
Assistance with this project was provided by Brian Flock