OJE  Vol.4 No.4 , March 2014
Long Term Effect of Major Disturbances on the Northern Mixed Grassland Ecosystem—A Review
Abstract: Grassland ecosystems in North America have been significantly altered through various disturbances from past to present. This paper has identified and examined major disturbances in the grassland ecosystems, which include grazing, fire and drought. A brief history of each disturbance is reviewed and its impact on the grassland ecosystem is discussed, by synthesizing previous research efforts available in the current literature. The paper intends to understand the grassland ecosystem from a comprehensive perspective and particularly tries to articulate the compound effect of the major disturbances in the same context instead of viewing them in isolations. It is concluded that a holistic understanding of the interaction between disturbances and plant communities is essential for sustainable grassland management, which demands comprehensive research effort in this area. The paper also points out the challenges we are facing in the current researches and suggests potential future improvement.
Cite this paper: Li, M. and Guo, X. (2014) Long Term Effect of Major Disturbances on the Northern Mixed Grassland Ecosystem—A Review. Open Journal of Ecology, 4, 214-233. doi: 10.4236/oje.2014.44021.

[1]   Anderson, R.C. (2006) Evolution and Origin of the Central Grassland of North America: Climate, Fire, and Mammalian Grazers. The Journal of the Torrey Botanical Society, 133, 626-647.[626:EAOOTC]2.0.CO;2

[2]   Shantz, H.L. (1954) The Place of Grasslands in the Earth’s Cover of Vegetation. Ecology, 35, 143-145.

[3]   Vitousek, P. and Hooper, D. (1993) Biological Diversity and Terrestrial Ecosystem Biogeochemistry. In: Biodiversity and Ecosystem Function, Springer, Berlin, 3-140.

[4]   Sala, O., Chapin, F.I., Armesto, J., Berlow, E., Bloomfield, J., Dirzo, R., Huber-Sanwald, E., Huenneke, L., Jackson, R., Kinzig, A., Leemans, R., Lodge, D., Mooney, H., Oesterheld, M., Poff, N., Sykes, M., Walker, B., Walker, M. and Wall, D. (2000) Global Biodiversity Scenarios for the Year 2100. Science, 287, 1770-1774.

[5]   Sala, O., van Vuuren, D. and Pereira, H. (2005) Biodiversity across Scenarios. Ecosystems and Human Well Being Scenario, Island Press, Washington DC, 375-408.

[6]   Ford, P.L. and McPherson, G.R. (1996) Ecology of Fire in Shortgrass Prairie of the Southern Great Plains. In: Finch, D.M., Ed., Ecosystem Disturbance and Wildlife Conservation in Western Grasslands—A Symposium Proceedings. Diane Publishing Co., Darby, 20-39.

[7]   White, P.S. (1979) Pattern, Process, and Natural Disturbance in Vegetation. The Botanical Review, 45, 229-299.

[8]   Gibson, D.J. and Hulbert, L.C. (1987) Effects of Fire, Topography and Year-to-Year Climatic Variation on Species Composition in Tallgrass Prairie. Vegetatio, 72, 175-185

[9]   Anderson, R.C. (1990) Fire in North American Tallgrass Prairies. University of Oklahoma Press, Norman, 8-18.

[10]   Savage, C (2011) Priaire: A Natural History. 2nd Edition, Greystone Books/David Suzuki Foundation, Vancouver.

[11]   Shay, J., Whelan-Enns, G., Appleby, A., Usher, R., Kavanagh, K., Sims, M., Chaplin, S., Sims, P., Carney, K. and Dinerstein, E. (2013) Northern Mixed Grasslands.

[12]   Cunfer, G. (2005) On the Great Plains: Agriculture and Environment. Texas A&M University Press, College Station.

[13]   Archibold, O.W. and Wilson, M.R. (1980) The Natural Vegetation of Saskatchewan Prior to Agricultural Settlement. Canadian Journal of Botany, 58, 2031-2042.

[14]   Savage, C. (2011) Prairie—A Natural History. D & M Publishers Inc., Vancouver.

[15]   WWF Global (2009) Northern Great Plains.

[16]   Collins, S.L. (1987) Interaction of Disturbances in Tallgrass Prairie: A Field Experiment. Ecology, 68, 1243-1250.

[17]   Gibson, D.J. (1989) Effects of Animal Disturbance on Tallgrass Prairie Vegetation. American Midland Naturalist, 121, 144-154.

[18]   Gibson, D.J. (2009) Grasses & Grassland Ecology. Oxford University Press Inc., New York.

[19]   Kansas Natural Heritage Inventory (2007) Native Prairie Hay Meadows: A Landowner’s Management Guide. University of Kansas, Lawrence.

[20]   Parton, W.J., Scurlock, J.M.O., Ojima, D.S., Schimel, D.S. and Hall, D.O. (1995) Impact of Climate Change on Grassland Production and Soil Carbon Worldwide. Global Change Biology, 1, 13-22

[21]   Polis, G.A. (1999) Why Are Parts of the World Green? Multiple Factors Control Productivity and the Distribution of Biomes. Oikos, 86, 3-15.

[22]   Hairston, N. (1960) Community Structure, Population Control and Competition. The American Naturalist, 94, 421-425.

[23]   White, P.S. and Pickett, S.T.A. (1985) Natural Disturbance and Patch Dynamics: An Introduction. In: The Ecology of Natural Disturbance and Patch Dynamics, Academic Press, Orlando, 3-16.

[24]   Collins, S.L. and Glenn, S.M. (1988) Disturbance and Community Structure in North American Prairies. In: Diversity and Pattern in Plant Communities, SPB Academic, The Hague, 131-143.

[25]   Arnold, E. (1992) World Atlas of Desertification. UNEP, London.

[26]   Briske, D.D., Fuhlendorf, S.D. and Smeins, F.E. (2003) Vegetation Dynamics on Rangelands—A Critique of the Current Paradigms. Journal of Applied Ecology, 40, 601-614.

[27]   Dobak, W.A. (1996) Killing the Canadian Buffalo. The Western Historical Quarterly, 27, 33-52.

[28]   Bruynooghe, J. and Macdonald, R. (2008) Managing Saskatchewan Rangeland. Revised Edition, Agriculture and AgriFood Canada, Saskatoon.

[29]   Detling, J.K. (1988) Grasslands and Savannas: Regulation of Energy Flow and Nutrient Cycling by Herbivores. Concepts of Ecosystem Ecology, 67, 131-148.

[30]   McNaughton, S.J. (1986) On Plants and Herbivores. The American Naturalist, 128, 765-770.

[31]   Paige, K.N. and Whitham, T.G. (1987) Over Compensation in Response to Mammalian Herbivory: The Advantage of Being Eaten. The American Naturalist, 129, 407-416.

[32]   Boddey, R.M., Macedo, R., Tarre, R.M., de Oliveira, O.C. and Rezende, C.D. (2004) Nitrogen Cycling in Brachiaria Pastures: The Key to Understanding the Process of Pasture decline. Agriculture, Ecosystems & Environment, 103, 389-403.

[33]   McNaughton, S.J. (1979) Grazing as an Optimization Process: Grass-Ungulate Relationships in the Serengeti. The American Naturalist, 113, 691-703.

[34]   Patton, B.D., Dong, X.P., Nyren, E. and Nyren, A. (2007) Effects of Grazing Intensity, Precipitation and Temperature on Forage Production. Rangel Ecology Management, 60, 656-665.

[35]   Belsky, A.J. (1986) Does Herbivory Benefit Plants? A Review of the Evidence. The American Naturalist, 127, 870-892.

[36]   Milchunas, D.G., Forwood, J.R. and Lauenroth, W.K. (1994) Productivity of Long-Term Grazing Treatments in Response to Seasonal Precipitation. Journal of Range Management, 47, 133-139.

[37]   Collins, S.L. and Steinauer, E.M. (1998) Disturbance, Diversity, and Species Interactions in Tallgrass Prairie. In: Grassland Dynamics: Long-Term Ecological Research in Tallgrass Prairie, Oxford University Press, Inc., New York, 140-156.

[38]   Adler, P.B., Raff, D.A. and Lauenroth, W.K. (2001) The Effect of Grazing on the Spatial Heterogeneity of Vegetation. Oecologia, 128, 465-479.

[39]   Hobbs, R.J. and Huenneke, L.F. (1992) Disturbance, Diversity, and Invasion: Implications for Conservation. Conservation Biology, 6, 324-337.

[40]   McNaughton, S.J., Wallace, L.L. and Coughenour, M.B. (1983) Plant Adaptation in an Ecosystem Context: Effects of Defoliation, Nitrogen, and Water on Growth of an African C4 Sedge. Ecology, 64, 307-318.

[41]   Olff, H. and Ritchie, M.E. (1998) Effects of Herbivores on Grassland Plant Diversity. Trends in Ecology & Evolution, 13, 261-265.

[42]   Dyksterhuis, E.J. (1949) Condition and Management of Rangeland Based on Quantitative Ecology. Journal of Range Management, 41, 450-459.

[43]   Dyer, M.I., Detling, J.K., Coleman, D.C. and Hilbert, D.W. (1982) The Role of Herbivores in Grasslands. In: Grasses and Grasslands, University of Oklahoma Press, Norman, 255-295.

[44]   Milchunas, D.G. and Lauenroth, W.K. (1993) Quantitative Effects of Grazing on Vegetation and Soils over a Global Range of Environments. Ecological Monographs, 63, 327-366.

[45]   Milchunas, D.G., Sala, O.E. and Lauenroth, W.K. (1988) A Generalized Model of the Effects of Grazing by Large Herbivores on Grassland Community Structure. The American Naturalist, 132, 87-106.

[46]   Bakker, C., Blair, J.M. and Knapp, A.K. (2003) Does Resource Availability, Resource Heterogeneity or Species Turnover Mediate Changes in Plant Species Richness in Grazed Grasslands? Oecologia, 137, 385-391.

[47]   Westoby, M., Walker, B. and Noy-meir, I. (1989) Opportunistic Management for Rangelands Not at Equilibrium. Journal of Range Management, 42, 266-274.

[48]   Jamsranjav, C. (2009) Sustainable Rangeland Management in Mongolia?: The Role of Herder Community Institutions. Reykjavik, Iceland, 1-36.

[49]   Pyne, S.J. (2001) Fire: A Brief History. University of Washington Press, Seattle.

[50]   Pyne, S.J. (1982) Fire in America: A Cultural History of Wildland and Rural Fire. Princeton University Press, Princeton.

[51]   Barrett, S. and Arno, S. (1999) Indian Fires in the Northern Rockies. In: Indians, Fire L.—Pacific Northwest, Oregon State University Press, Corvallis, 50-62.

[52]   Pyne, S.J. (2001) Fire: A Brief History. University of Washington Press, Seattle.

[53]   Ford, P.L. and McPerson, G.R. (1998) Trillium cernuum, the Rediscovery of the Species and the Ecological Restoration of Its Surrounding Habitat. Proceedings of 15th North American Prairie Conference, Natural Areas Association, Bend, 71-76. econatres.napc15.pford.pdf

[54]   Courtwright, J. (2007) “When We First Come Here It All Looked like Prairie Land Almost”: Prairie Fire and Plains Settlement. The Western Historical Quarterly, 38, 157-179.

[55]   Chapman, H.H. (1936) Effects of Fire in Propagation of Seedbed for Longleaf Pine Seedlings. Journal of Forestry, 34, 852-854.

[56]   Heyward, F. (1937) The Effect of Frequent Fires on Profile Development of Longleaf Pine Forest Soils. Journal of Forestry, 35, 23-27.

[57]   Wright, H.A. and Bailey, A. (1982) Fire Ecology—United States and Southern Canada. John Wiley and Sons, New York.

[58]   Sauer, C. (1950) Grassland Climax, Fire, and Man. Journal of Range Management, 3, 16-21.

[59]   Bond, W.J. and Keeley, J.E. (2005) Fire as a Global “Herbivore”: The Ecology and Evolution of Flammable Ecosystems. Trends in Ecology & Evolution, 20, 387-394.

[60]   Grover, H.D. and Musick, H.B. (1990) Shrubland Encroachment in Southern New Mexico, U.S.A.: An Analysis of Desertification Processes in the American Southwest. Climatic Change, 17, 305-330.

[61]   Ford, P.L. and Johnson, G.V. (2006) Effects of Dormantvs. Growing-Season Fire in Shortgrass Steppe: Biological Soil Crust and Perennial Grass Responses. Journal of Arid Environments, 67, 1-14.

[62]   Dwyer, D.D. and Pieper, R.D. (1967) Fire Effects of Blue Grama-Pinyon-Juniper Rangeland in New Mexico. Journal of Range Management, 20, 359-362.

[63]   Launchbaugh, J.L. (1964) Effects of Early Spring Burning on Yields of Native Vegetation. Journal of Range Management, 17, 5-6.

[64]   Steuter, A.A. and McPherson, G.R. (1995) Fire as a Physical Stress. In: Bedunah, D.J. and Sosebee, R.E., Eds., Wildland Plants: Physiological Ecology and Developmental Morphology, Society for Range Management, Denver, 550-579.

[65]   Uys, R. (2004) The Effects of Different Fire Regimes on Plant Diversity in Southern African Grasslands. Biological Conservation, 118, 489-499.

[66]   Leach, M.K. and Givnish, T.J. (1996) Ecological Determinants of Species Loss in Remnant Prairies. Science, 273, 1555-1558.

[67]   Peterson, D.W. and Reich, P.B. (2001) Prescribed Fire in Oak Savanna: Fire Frequency Effects on Stand Structure and Dynamics. Ecological Applications, 11, 914-927.[0914:PFIOSF]2.0.CO;2

[68]   Scasta, J.D., Engle, D.M., Talley, J.L., Weir, J.R., Stansberry, J.C., Fuhlendorf, S.D. and Harr, R.N. (2012) Pyric-Herbivory to Manage Horn Flies (Diptera: Muscidae) on Cattle. Southwestern Entomologist, 37, 325-334.

[69]   Anderson, K.L., Smith, E.F. and Owensby, C.E. (1970) Burning Bluestem Range. Journal of Range Management, 23, 81-92.

[70]   Heirman, A.L. and Wright, H.A. (1973) Fire in Medium Fuels of West Texas. Journal of Range Management, 26, 331-335.

[71]   White, R.S. and Currie, P.O. (1983) Prescribed Burning in the Northern Great Plains: Yield and Cover Responses of 3 Forage Species in the Mixed Grass Prairie. Journal of Range Management, 36, 179-183.

[72]   Umbanhowar, C.E. (1996) Recent Fire History of the Northern Great Plains. American Midland Naturalist, 135, 115-121.

[73]   Brockway, D.G., Gatewood, R.G. and Paris, R.B. (2002) Restoring Fire and an Ecological Process in Shortgrass Prairie Ecosystems: Initial Effects of Prescribed Burning during the Dormant and Growing Seasons. Journal of Environmental Management, 65, 135-152.

[74]   Guo, X., Price, K.P. and Stiles, J.M. (2000) Biophysical and Spectral Characteristics of Cool and Warm-Season Grasslands under Three Land Management Practices in Eastern Kansas. Natural Resources Research, 9, 321-331.

[75]   Dubinin, M., Potapov, P., Lushchekina, A. and Radeloff, V.C. (2010) Reconstructing Long Time Series of Burned Areas in Arid Grasslands of Southern Russia by Satellite Remote Sensing. Remote Sensing of Environment, 114, 1638-1648.

[76]   Scholes, R.J. and Archer, S.R. (1997) Tree-Grass Interactions in Savannas. Annual Review of Ecology and Systematics, 28, 517-544.

[77]   Lieth, H.F.H. (1978) Patterns of Primary Productivity in the Biosphere. Hutchinson Ross, Stroudsberg.

[78]   Rosenzweig, M.L. (1968) Net Primary Productivity of Terrestrial Communities: Prediction from Climatological Data. The American Naturalist, 102, 67-74.

[79]   Whittaker, R.H. (1975) Communities and Ecosystems. 2nd Revise Edition, MacMillan Publishing Co., New York.

[80]   Oesterheld, M., Loreti, J., Semmartin, M. and Paruelo, J.M. (1999) Grazing, Fire, and Climate Effects on Primary Productivity of Grasslands and Savanna. In: Walker, L.L., Ed., Ecosystems of Disturbed Grounds, Series Ecosystems of the World, Elsevier, New York, 287-306.

[81]   Sherow, J.E. (1992) Workings of the Geodialectic: High Plains Indians and Their Horses in the Region of the Arkansas River Valley, 1800-1870. Environmental History Review, 16, 61-84.

[82]   NOAA (2014) North American Drought—A Paleo Perspective (Paleoclimatology and Drought). National Climatic Data Center, 1.

[83]   Knapp, A.K. and Smith, M.D. (2001) Variation among Biomes in Temporal Dynamics of Aboveground Primary Production. Science, 291, 481-484.

[84]   Lauenroth, W.K. and Sala, O. (1992) Long-Term Forage Production of the North American Shortgrass Steppe. Ecological Applications, 2, 397-403.

[85]   Warren, W., Stan, S., William, L., Russell, K. and Milton, S. (1978) Primary Productivity and Water Use in Native Forest, Grassland, and Desert Ecosystems. Ecology, 59, 1239-1247.

[86]   Hopkins, H., Albertson, F.W. and Riegel, A. (1948) Some Effects of Burning upon a Prairie in West-Central Kansas. Transactions of the Kansas Academy of Science, 51, 131-141.

[87]   Knapp, E.E., Estes, B.L. and Skinner, C.N. (2009) Ecological Effects of Prescribed Fire Season: A Literature Review and Synthesis for Managers. Department of Agriculture, Forest Service, Pacific Southwest Research Station, Albany.

[88]   Agee, J.K. (1993) Fire Ecology of Pacific Northwest Forests. Island Press, Covelo.

[89]   Brown, J.K. (2000) Introduction and Fire Regimes. In: Wildland Fire in Ecosystems: Effect of Fire on Flora, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Ogden, 1-7.

[90]   Van Langevelde, F., Van De Vijver, C.A.D.M., Kumar, L., Van De Koppel, J., De Ridder, N., Van Andel, J., Skidmore, A.K., Hearne, J.W., Stroosnijder, L., Bond, W.J., Prins, H.H.T. and Rietkerk, M. (2003) Effects of Fire and Herbivory on the Stability of Savanna Ecosystems. Ecology, 84, 337-350.[0337:EOFAHO]2.0.CO;2

[91]   Spasojevic, M.J., Aicher, R.J., Koch, G.R., Marquardt, E.S., Mirotchnick, N., Troxler, T.G. and Collins, S.L. (2010) Fire and Grazing in a Mesic Tallgrass Prairie: Impacts on Plant Species and Functional Traits. Ecology, 91, 1651-1659.

[92]   Hulbert, L.C. (1985) History and Use of Konza Prairie Research Natural Area. Prairie Scout, 5, 63-93.

[93]   Ehleringer, J.R. and Monson, R.K. (1993) Evolutionary and Ecological Aspects of Photosynthetic Pathway Variation. Annual Review of Ecology, Evolution, and Systematics, 24, 411-439.

[94]   Collins, S.L. and Smith, M.D. (2006) Scale-Dependent Interaction of Fire and Grazing on Community Heterogeneity in Tallgrass Prairie. Ecology, 87, 2058-2067.[2058:SIOFAG]2.0.CO;2

[95]   Fuhlendorf, S.D. and Engle, D.M. (2004) Application of the Fire-Grazing Interaction to Restore a Shifting Mosaic on Tallgrass Prairie. Journal of Applied Ecology, 41, 604-614.

[96]   Whelan, R.J. (1995) The Ecology of Fire. Cambridge University Press, Cambridge.

[97]   Keeley, J.E., Lubin, D. and Fotheringham, C.J. (2003) Fire and Grazing Impacts on Plant Diversity and Alien Plant Invasions in the Southern Sierra Nevada. Ecological Applications, 13, 1355-1374.

[98]   Trager, M.D., Wilson, G.W.T. and Hartnett, D.C. (2004) Concurrent Effects of Fire Regime, Grazing and Bison Wallowing on Tallgrass Prairie Vegetation. The American Midland Naturalist, 152, 237-247.[0237:CEOFRG]2.0.CO;2

[99]   Fuhlendorf, S.D., Engle, D.M., Kerby, J. and Hamilton, R. (2009) Pyric Herbivory: Rewilding Landscapes through the Recoupling of Fire and Grazing. Conservation Biology, 23, 588-598.

[100]   Weir, J.R., Fuhlendorf, S.D., Engle, D.M., Bidwell, T.G., Cumminggs, D.C. and Elmore, D. (2007) Patch Burning: Integrating Fire and Grazing to Promote Heterogeneity. Oklahoma State University, Stillwater.

[101]   Allred, B.W., Fuhlendorf, S.D., Engle, D.M. and Elmore, R.D. (2011) Ungulate Preference for Burned Patches Reveals Strength of Fire-Grazing Interaction. Ecology and Evolution, 1, 132-144.

[102]   Kagima, B. and Eairbanks, W.S. (2013) Habitat Selection and Diet Composition of Reintroduced Native Ungulates in a Fire-Managed Tallgrass Prairie Reconstruction. Ecological Restoration, 21, 79-88.

[103]   Archibald, S., Bond, W.J., Stock, W.D. and Fairbanks, D.H.K. (2005) Shaping the Landscape: Fire-Grazer Interactions in an African savanna. Ecological Applications, 15, 96-109.

[104]   McGranahan, D.A., Engle, D.M., Fuhlendorf, S.D., Winter, S.J., Miller, J.R. and Debinski, D.M. (2012) Spatial Heterogeneity across Five Rangelands Managed with Pyric-Herbivory. Journal of Applied Ecology, 49, 903-910.

[105]   Yang, X. (2012) Assessing Responses of Grasslands to Grazing Management Using Remote Sensing Approaches. University of Saskatchewan, Saskatoon.

[106]   Ellis, J.E. and Swift, D.M. (1988) Stability of African pastoral Ecosystems: Alternate Paradigms and Implications for Development. Journal of Range Management, 41, 450-459.

[107]   Biondini, M.E. and Manske, L. (1996) Grazing Frequency and Ecosystem Processes in Northern Mixed Prairie, USA. Ecological Applications, 6, 239-256.

[108]   Fuhlendorf, S.D., Briske, D.D. and Smeins, F.E. (2001) Herbaceous Vegetation Change in Variable Rangeland Environments: The Relative Contribution of Grazing and Climatic Variability. Applied Vegetation Science, 4, 177-188.

[109]   Gill, A.M. (1975) Fire and the Australian Flora: A Review. Australian Forestry, 38, 4-25.

[110]   Rothermal, R.C. (1983) How to Predict the Spread and Intensity of Forest and Range Fires. U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station, Ogden.

[111]   Andrews, P L (1986) BEHAVE: Fire Behavior Prediction and Fuel Modeling System/Burn Subsystem, Part I. General Technical Report INT-GTR-194, USDA Forest Service, Intermountain Research Station, Ogden.

[112]   Briske, D.D. (1991) Developmental Morphology and Physiology of Grasses. In: Grazing Management: An Ecological Perspective, Timber Press, Portland, 85-108.

[113]   Evans, E.W., Briggs, J.M., Finck, E.J., Gibson, D.J. and James, S.W. (1988) Is Fire a Disturbance in Grasslands? Proceedings of the North American Prairie Conferences, Lincoln, 7-11 August 1988, 159-161.

[114]   Chaneton, E.J., Perelman, S.B., Omacini, M. and Le, R.J.C. (2002) Grazing, Environmental Heterogeneity, and Alien Plant Invasions in Temperate Pampa grasslands. Biological Invasions, 4, 7-24.

[115]   Grimm, V. and Railsback, F. (2005) Individual-Based Modeling and Ecology. Princeton University Press, Princeton.

[116]   Tansley, A.G. (1935) The Use and Abuse of Vegetational Concepts and Terms. Ecology, 16, 284-307.

[117]   Ludwig, J.A. and Tongway, D.J. (1995) Spatial Organisation of Landscapes and Its Function in Semi-Arid Woodlands, Australia. Landscape Ecology, 10, 51-63.

[118]   Urban, D.L., O’Neill, R.V. and Shugart, H.H.J. (1987) Ecology Landscape Spatial Patterns. BioScience, 37, 119-127.

[119]   He, Y., Guo, X. and Wilmshurst, J. (2006) Studying Mixed Grassland Ecosystems I: Suitable Hyperspectral Vegetation indices. Canadian Journal of Remote Sensing, 32, 98-107.

[120]   Reynolds, H.L., Hungate, B.A., Chapin, F.S. and D’Antonio, C.M. (1997) Soil Heterogeneity and Plant Competition in an Annual Grassland. Ecology, 78, 2076-2090.

[121]   Sebastian, M.T. (2004) Role of Topography and Soils in Grassland Structuring at the Landscape and Community Scales. Basic and Applied Ecology, 5, 331-346.

[122]   Collins, S.L. and Barber, S.C. (1985) Effects of Disturbance on Diversity in Mixed-Grass Prairie. Vegetatio, 64, 87-94.

[123]   Barrett, T.M. (2001) Models of Vegetative Change for Landscape Planning: A Comparison of FETM, LANDSUM, SIMPPLLE, and VDDT. General Technical Report, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Ogden.

[124]   ESSA Technologies Ltd. (2013) Vegetation Dynamics Development Tool. ESSA Homepage, 1.

[125]   Kurz, W.A., Beukema, S.J., Klenner, W., Greenough, J.A., Robinson, D.C.E., Sharpe, A.D. and Webb, T.M. (2000) TELSA: The Tool for Exploratory Landscape Scenario Analyses. Computers and Electronics in Agriculture, 27, 227-242.

[126]   ESSA Technologies Ltd. (2008) TELSA?: Tool for Exploratory Landscape Scenario Analyses Model Description, Version 3, 6. Vancouver.

[127]   Hemstrom, M.A., Korol, J.J. and Hann, W.J. (2001) Trends in Terrestrial Plant Communities and Landscape Health Indicate the Effects of Alternative Management Strategies in the Interior Columbia River Basin. Forest Ecology and Management, 5504, 1-21.

[128]   LANDFIRE Helpdesk (2013) LANDFIRE. LANDFIRE Homepage, 1.

[129]   Wilmshurst, J.F., Walton, R. and Frid, L. (2007) TELSA Model Development 2005-2007. Parks Canada Agency, Western & Northern Service Center, Winnipeg.