Global assessment of the non-equilibrium concept in rangelands

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Global assessment of the non-equilibrium concept in rangelands. / Wehrden, H.V.; Hanspach, Jan; Kaczensky, Petra et al.
in: Ecological Applications, Jahrgang 22, Nr. 2, 03.2012, S. 393-399.

Publikation: Beiträge in ZeitschriftenZeitschriftenaufsätzeForschungbegutachtet

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@article{62c7390f0f8047de9ffdd65e2582c927,
title = "Global assessment of the non-equilibrium concept in rangelands",
abstract = "The non-equilibrium concept of rangeland dynamics predicts that the potential for grazing-induced degradation is low in rangelands with relatively variable precipitation. To date, evidence in support of the non-equilibrium concept has been inconsistent. Using a standardized protocol, including a newly developed global map of rainfall variability, we reviewed the incidence of degradation in relation to rainfall variability across 58 published studies. We distinguished between (1) zonal degradation (i.e., degradation independent of water and key resources), (2) degradation in the presence of key resources, and (3) degradation in the presence of water. For studies not affected by proximity to permanent water or key resources, we found strong support for the non-equilibrium concept for rangelands. Zonal degradation was absent at CV (coefficient of variation) values above 33%, which has been proposed as a critical threshold. Grazing degradation was almost entirely restricted to areas with relatively stable annual precipitation as expressed by a low CV, or to rangelands with key resources or water points nearby. To better understand rangeland dynamics, we recommend that future studies use globally comparable measures of degradation and rainfall variability. Our work underlines that rangelands with relatively stable rainfall patterns, and those with access to water or key resources, are potentially vulnerable to degradation. Grazing management in such areas should incorporate strategic rest periods. Such rest periods effectively mimic natural fluctuations in herbivore populations, which are a defining characteristic of non-degraded rangelands occurring under highly variable precipitation regimes.",
keywords = "Climatic variability, Degradation, Drylands, Grazing, Rainfall, Rangeland management, climate variation, environmental degradation, global perspective, grazing management, herbivore, precipitation assessment, rainfall, rangeland, vulnerability, Ecosystems Research, Environmental planning",
author = "H.V. Wehrden and Jan Hanspach and Petra Kaczensky and J. Fischer and Karsten Wesche",
note = "Export Date: 21 May 2012 Source: Scopus CODEN: ECAPE doi: 10.1890/11-0802.1 Language of Original Document: English Correspondence Address: Wehrden, H.V.; Centre of Methods, Leuphana University L{\"u}neburg, Scharnhorststrasse 1, 21335 L{\"u}neburg, Germany; email: vonwehrd@leuphana.de References: Begzsuren, S., Ellis, J.E., Ojima, D.S., Coughenour, M.B., Chuluun, T., Livestock responses to droughts and severe winter weather in the Gobi Three Beauty National Park, Mongolia (2004) Journal of Arid Environments, 59 (4), pp. 785-796. , DOI 10.1016/j.jaridenv.2004.02.001, PII S0140196304000503; Bestelmeyer, B.T., Trujillo, D.A., Tugel, A.J., Havstad, K.M., A multi-scale classification of vegetation dynamics in arid lands: What is the right scale for models, monitoring, and restoration? (2006) Journal of Arid Environments, 65 (2), pp. 296-318. , DOI 10.1016/j.jaridenv.2005.06.028, PII S0140196305001618, Landscape Linkages and Cross Scale Interactions in Arid and Semiarid Ecosystems; Boone, R.B., Wang, G., Cattle dynamics in African grazing systems under variable climates (2007) Journal of Arid Environments, 70 (3), pp. 495-513. , DOI 10.1016/j.jaridenv.2007.02.002, PII S0140196307000547; Briske, D.D., Fuhlendorf, S.D., Smeins, F.E., Vegetation dynamics on rangelands: A critique of the current paradigms (2003) Journal of Applied Ecology, 40 (4), pp. 601-614. , DOI 10.1046/j.1365-2664.2003.00837.x; Buttolph, L.P., Coppock, D.L., Influence of deferred grazing on vegetation dynamics and livestock productivity in an Andean pastoral system (2004) Journal of Applied Ecology, 41 (4), pp. 664-674. , DOI 10.1111/j.0021-8901.2004.00921.x; Costanza, R., The value of the world's ecosystem services and natural capital (1997) Nature, 387, pp. 253-260; Dregne, H.E., Land degradation in the drylands (2002) Arid Land Research and Management, 16 (2), pp. 99-132. , DOI 10.1080/153249802317304422; Ellis, J.E., Swift, D.M., Stability of African pastoral ecosystems: Alternate paradigms and implications for development (1988) Journal of Rangeland Management, 41, pp. 450-459; Evans, J., Geerken, R., Discrimination between climate and human-induced dryland degradation (2004) Journal of Arid Environments, 57 (4), pp. 535-554. , DOI 10.1016/S0140-1963(03)00121-6; Fensham, R.J., Holman, J.E., Cox, M.J., Plant species responses along a grazing disturbance gradient in Australian grassland (1999) Journal of Vegetation Science, 10 (1), pp. 77-86; Fernandez-Gimenez, M.E., Allen-Diaz, B., Testing a non-equilibrium model of rangeland vegetation dynamics in Mongolia (1999) Journal of Applied Ecology, 36 (6), pp. 871-885. , DOI 10.1046/j.1365-2664.1999.00447.x; Fuhlendorf, S.D., Smeins, F.E., Long-term vegetation dynamics mediated by herbivores, weather and fire in a Juniperus-Quercus savanna (1997) Journal of Vegetation Science, 8 (6), pp. 819-828; Geerken, R., Ilaiwi, M., Assessment of rangeland degradation and development of a strategy for rehabilitation (2004) Remote Sensing of Environment, 90 (4), pp. 490-504. , DOI 10.1016/j.rse.2004.01.015, PII S0034425704000240; Gillson, L., Timm Hoffman, M., Rangeland ecology in a changing world (2007) Science, 315 (5808), pp. 53-54. , DOI 10.1126/science.1136577; Hanan, N.P., Prevost, Y., Diouf, A., Diallo, O., Assessment of desertification around deep wells in the Sahel using satellite imagery (1991) Journal of Applied Ecology, 28, pp. 173-186; Harrison, S., Inouye, B.D., Safford, H.D., Ecological heterogeneity in the effects of grazing and fire on grassland diversity (2003) Conservation Biology, 17 (3), pp. 837-845. , DOI 10.1046/j.1523-1739.2003.01633.x; Hijmans, R.J., Cameron, S.E., Parra, J.L., Jones, P.G., Jarvis, A., Very high resolution interpolated climate surfaces for global land areas (2005) International Journal of Climatology, 25 (15), pp. 1965-1978. , DOI 10.1002/joc.1276; Hostert, P., Roder, A., Hill, J., Udelhoven, T., Tsiourlis, G., Retrospective studies of grazing-induced land degradation: A case study in central Crete, Greece (2003) International Journal of Remote Sensing, 24 (20), pp. 4019-4034. , DOI 10.1080/0143116031000103844; Huebner, C.D., Vankat, J.L., The importance of environment vs. disturbance in the vegetation mosaic of Central Arizona (2003) Journal of Vegetation Science, 14 (1), pp. 25-34; Illius, A.W., O'Connor, T.G., On the relevance of nonequilibrium concepts to arid and semiarid grazing systems (1999) Ecological Applications, 9 (3), pp. 798-813; Illius, A.W., O'Connor, T.G., Resource heterogeneity and ungulate population dynamics (2000) Oikos, 89 (2), pp. 283-294; Leggett, K., Fennessy, J., Schneider, S., Seasonal vegetation changes in the Hoanib River catchment, north-western Namibia: A study of a non-equilibrium system (2003) Journal of Arid Environments, 53 (1), pp. 99-113. , DOI 10.1006/jare.2002.1027; Miehe, S., Kluge, J., Von Wehrden, H., Retzer, V., Long-term degradation of Sahelian rangeland detected by 27 years of field study in Senegal (2010) Journal of Applied Ecology, 47, pp. 692-700; Milchunas, D.G., Lauenroth, W.K., Quantitative effects of grazing on vegetation and soils over a global range of environments (1993) Ecological Monographs, 63, pp. 327-366; Milchunas, D.G., Lauenroth, W.K., Burke, I.C., Detling, J.K., Effects of grazing on vegetation (2008) Ecology of the Shortgrass Steppe, pp. 389-446. , W. K. Lauenroth and I. C. Burke, editors Oxford University Press, New York, New York, USA; Muller, B., Quaas, M.F., Frank, K., Baumgartner, S., Pitfalls and potential of institutional change: Rain-index insurance and the sustainability of rangeland management (2011) Ecological Economics, 70, pp. 2137-2144; Mwalyosi, R.B.B., Influence of livestock grazing on range condition in south-west Masailand, northern Tanzania (1992) Journal of Applied Ecology, 29 (3), pp. 581-588; Noy-Meir, I., Interactive effects of fire and grazing on structure and diversity of Mediterranean grasslands (1995) Journal of Vegetation Science, 6 (5), pp. 701-710; Olff, H., Ritchie, M.E., Prins, H.H.T., Global environmental controls of diversity in large herbivores (2002) Nature, 415 (6874), pp. 901-904. , DOI 10.1038/415901a; Oliva, G., Cibils, A., Borrelli, P., Humano, G., Stable states in relation to grazing in Patagonia: A 10-year experimental trial (1998) Journal of Arid Environments, 40 (1), pp. 113-131. , DOI 10.1006/jare.1998.0425; (2009) R: A Language and Environment for Statistical Computing, , www.r-project.org, R Development Core Team R Foundation for Statistical Computing, Vienna, Austria; Reynolds, J.F., Stafford Smith, D.M., Lambin, E.F., Turner II, B.L., Mortimore, M., Batterbury, S.P.J., Downing, T.E., Walker, B., Ecology: Global desertification: Building a science for dryland development (2007) Science, 316 (5826), pp. 847-851. , DOI 10.1126/science.1131634; Sullivan, S., The impacts of people and livestock on topographically diverse open wood-and shrub-lands in arid north-west Namibia (1999) Global Ecology and Biogeography, 8, pp. 257-277; Tadey, M., Farji-Brener, A.G., Indirect effects of exotic grazers: Livestock decreases the nutrient content of refuse dumps of leaf-cutting ants through vegetation impoverishment (2007) Journal of Applied Ecology, 44 (6), pp. 1209-1218. , DOI 10.1111/j.1365-2664.2007.01338.x; Thompson Hobbs, N., Schimel, D.S., Owensby, C.E., Ojima, D.S., Fire and grazing in the tallgrass prairie: Contingent effects on nitrogen budgets (1991) Ecology, 72, pp. 1374-1382; Vetter, S., Rangelands at equilibrium and non-equilibrium: Recent developments in the debate (2005) Journal of Arid Environments, 62 (2), pp. 321-341. , DOI 10.1016/j.jaridenv.2004.11.015; Walker, B.H., Janssen, M.A., Rangelands, pastoralists and governments: Interlinked systems of people and nature (2002) Philosophical Transactions of the Royal Society B: Biological Sciences, 357 (1421), pp. 719-725. , DOI 10.1098/rstb.2001.0984; Wessels, K.J., Prince, S.D., Malherbe, J., Small, J., Frost, P.E., VanZyl, D., Can human-induced land degradation be distinguished from the effects of rainfall variability? A case study in South Africa (2007) Journal of Arid Environments, 68 (2), pp. 271-297. , DOI 10.1016/j.jaridenv.2006.05.015, PII S014019630600190X; West, N.E., Biodiversity of rangelands (1993) Journal of Range Management, 46 (1), pp. 2-13; White, R.P., Murray, S., Rohweder, M., (2000) Pilot Analysis of Global Ecosystems, , Grassland ecosystems. World Resource Institute, Washington, D.C., USA; Ji, Y.Z., Wang, Y., Zhao, X., Xie, G., Zhang, T., Grassland recovery by protection from grazing in a semi-arid sandy region of northern China (2005) New Zealand Journal of Agricultural Research, 48 (2), pp. 277-284; Zhao, W.Y., Li, J.L., Qi, J.G., Changes in vegetation diversity and structure in response to heavy grazing pressure in the northern Tianshan Mountains, China (2007) Journal of Arid Environments, 68 (3), pp. 465-479. , DOI 10.1016/j.jaridenv.2006.06.007, PII S0140196306002308",
year = "2012",
month = mar,
doi = "10.1890/11-0802.1",
language = "English",
volume = "22",
pages = "393--399",
journal = "Ecological Applications",
issn = "1051-0761",
publisher = "John Wiley & Sons Inc.",
number = "2",

}

RIS

TY - JOUR

T1 - Global assessment of the non-equilibrium concept in rangelands

AU - Wehrden, H.V.

AU - Hanspach, Jan

AU - Kaczensky, Petra

AU - Fischer, J.

AU - Wesche, Karsten

N1 - Export Date: 21 May 2012 Source: Scopus CODEN: ECAPE doi: 10.1890/11-0802.1 Language of Original Document: English Correspondence Address: Wehrden, H.V.; Centre of Methods, Leuphana University Lüneburg, Scharnhorststrasse 1, 21335 Lüneburg, Germany; email: vonwehrd@leuphana.de References: Begzsuren, S., Ellis, J.E., Ojima, D.S., Coughenour, M.B., Chuluun, T., Livestock responses to droughts and severe winter weather in the Gobi Three Beauty National Park, Mongolia (2004) Journal of Arid Environments, 59 (4), pp. 785-796. , DOI 10.1016/j.jaridenv.2004.02.001, PII S0140196304000503; Bestelmeyer, B.T., Trujillo, D.A., Tugel, A.J., Havstad, K.M., A multi-scale classification of vegetation dynamics in arid lands: What is the right scale for models, monitoring, and restoration? (2006) Journal of Arid Environments, 65 (2), pp. 296-318. , DOI 10.1016/j.jaridenv.2005.06.028, PII S0140196305001618, Landscape Linkages and Cross Scale Interactions in Arid and Semiarid Ecosystems; Boone, R.B., Wang, G., Cattle dynamics in African grazing systems under variable climates (2007) Journal of Arid Environments, 70 (3), pp. 495-513. , DOI 10.1016/j.jaridenv.2007.02.002, PII S0140196307000547; Briske, D.D., Fuhlendorf, S.D., Smeins, F.E., Vegetation dynamics on rangelands: A critique of the current paradigms (2003) Journal of Applied Ecology, 40 (4), pp. 601-614. , DOI 10.1046/j.1365-2664.2003.00837.x; Buttolph, L.P., Coppock, D.L., Influence of deferred grazing on vegetation dynamics and livestock productivity in an Andean pastoral system (2004) Journal of Applied Ecology, 41 (4), pp. 664-674. , DOI 10.1111/j.0021-8901.2004.00921.x; Costanza, R., The value of the world's ecosystem services and natural capital (1997) Nature, 387, pp. 253-260; Dregne, H.E., Land degradation in the drylands (2002) Arid Land Research and Management, 16 (2), pp. 99-132. , DOI 10.1080/153249802317304422; Ellis, J.E., Swift, D.M., Stability of African pastoral ecosystems: Alternate paradigms and implications for development (1988) Journal of Rangeland Management, 41, pp. 450-459; Evans, J., Geerken, R., Discrimination between climate and human-induced dryland degradation (2004) Journal of Arid Environments, 57 (4), pp. 535-554. , DOI 10.1016/S0140-1963(03)00121-6; Fensham, R.J., Holman, J.E., Cox, M.J., Plant species responses along a grazing disturbance gradient in Australian grassland (1999) Journal of Vegetation Science, 10 (1), pp. 77-86; Fernandez-Gimenez, M.E., Allen-Diaz, B., Testing a non-equilibrium model of rangeland vegetation dynamics in Mongolia (1999) Journal of Applied Ecology, 36 (6), pp. 871-885. , DOI 10.1046/j.1365-2664.1999.00447.x; Fuhlendorf, S.D., Smeins, F.E., Long-term vegetation dynamics mediated by herbivores, weather and fire in a Juniperus-Quercus savanna (1997) Journal of Vegetation Science, 8 (6), pp. 819-828; Geerken, R., Ilaiwi, M., Assessment of rangeland degradation and development of a strategy for rehabilitation (2004) Remote Sensing of Environment, 90 (4), pp. 490-504. , DOI 10.1016/j.rse.2004.01.015, PII S0034425704000240; Gillson, L., Timm Hoffman, M., Rangeland ecology in a changing world (2007) Science, 315 (5808), pp. 53-54. , DOI 10.1126/science.1136577; Hanan, N.P., Prevost, Y., Diouf, A., Diallo, O., Assessment of desertification around deep wells in the Sahel using satellite imagery (1991) Journal of Applied Ecology, 28, pp. 173-186; Harrison, S., Inouye, B.D., Safford, H.D., Ecological heterogeneity in the effects of grazing and fire on grassland diversity (2003) Conservation Biology, 17 (3), pp. 837-845. , DOI 10.1046/j.1523-1739.2003.01633.x; Hijmans, R.J., Cameron, S.E., Parra, J.L., Jones, P.G., Jarvis, A., Very high resolution interpolated climate surfaces for global land areas (2005) International Journal of Climatology, 25 (15), pp. 1965-1978. , DOI 10.1002/joc.1276; Hostert, P., Roder, A., Hill, J., Udelhoven, T., Tsiourlis, G., Retrospective studies of grazing-induced land degradation: A case study in central Crete, Greece (2003) International Journal of Remote Sensing, 24 (20), pp. 4019-4034. , DOI 10.1080/0143116031000103844; Huebner, C.D., Vankat, J.L., The importance of environment vs. disturbance in the vegetation mosaic of Central Arizona (2003) Journal of Vegetation Science, 14 (1), pp. 25-34; Illius, A.W., O'Connor, T.G., On the relevance of nonequilibrium concepts to arid and semiarid grazing systems (1999) Ecological Applications, 9 (3), pp. 798-813; Illius, A.W., O'Connor, T.G., Resource heterogeneity and ungulate population dynamics (2000) Oikos, 89 (2), pp. 283-294; Leggett, K., Fennessy, J., Schneider, S., Seasonal vegetation changes in the Hoanib River catchment, north-western Namibia: A study of a non-equilibrium system (2003) Journal of Arid Environments, 53 (1), pp. 99-113. , DOI 10.1006/jare.2002.1027; Miehe, S., Kluge, J., Von Wehrden, H., Retzer, V., Long-term degradation of Sahelian rangeland detected by 27 years of field study in Senegal (2010) Journal of Applied Ecology, 47, pp. 692-700; Milchunas, D.G., Lauenroth, W.K., Quantitative effects of grazing on vegetation and soils over a global range of environments (1993) Ecological Monographs, 63, pp. 327-366; Milchunas, D.G., Lauenroth, W.K., Burke, I.C., Detling, J.K., Effects of grazing on vegetation (2008) Ecology of the Shortgrass Steppe, pp. 389-446. , W. K. Lauenroth and I. C. Burke, editors Oxford University Press, New York, New York, USA; Muller, B., Quaas, M.F., Frank, K., Baumgartner, S., Pitfalls and potential of institutional change: Rain-index insurance and the sustainability of rangeland management (2011) Ecological Economics, 70, pp. 2137-2144; Mwalyosi, R.B.B., Influence of livestock grazing on range condition in south-west Masailand, northern Tanzania (1992) Journal of Applied Ecology, 29 (3), pp. 581-588; Noy-Meir, I., Interactive effects of fire and grazing on structure and diversity of Mediterranean grasslands (1995) Journal of Vegetation Science, 6 (5), pp. 701-710; Olff, H., Ritchie, M.E., Prins, H.H.T., Global environmental controls of diversity in large herbivores (2002) Nature, 415 (6874), pp. 901-904. , DOI 10.1038/415901a; Oliva, G., Cibils, A., Borrelli, P., Humano, G., Stable states in relation to grazing in Patagonia: A 10-year experimental trial (1998) Journal of Arid Environments, 40 (1), pp. 113-131. , DOI 10.1006/jare.1998.0425; (2009) R: A Language and Environment for Statistical Computing, , www.r-project.org, R Development Core Team R Foundation for Statistical Computing, Vienna, Austria; Reynolds, J.F., Stafford Smith, D.M., Lambin, E.F., Turner II, B.L., Mortimore, M., Batterbury, S.P.J., Downing, T.E., Walker, B., Ecology: Global desertification: Building a science for dryland development (2007) Science, 316 (5826), pp. 847-851. , DOI 10.1126/science.1131634; Sullivan, S., The impacts of people and livestock on topographically diverse open wood-and shrub-lands in arid north-west Namibia (1999) Global Ecology and Biogeography, 8, pp. 257-277; Tadey, M., Farji-Brener, A.G., Indirect effects of exotic grazers: Livestock decreases the nutrient content of refuse dumps of leaf-cutting ants through vegetation impoverishment (2007) Journal of Applied Ecology, 44 (6), pp. 1209-1218. , DOI 10.1111/j.1365-2664.2007.01338.x; Thompson Hobbs, N., Schimel, D.S., Owensby, C.E., Ojima, D.S., Fire and grazing in the tallgrass prairie: Contingent effects on nitrogen budgets (1991) Ecology, 72, pp. 1374-1382; Vetter, S., Rangelands at equilibrium and non-equilibrium: Recent developments in the debate (2005) Journal of Arid Environments, 62 (2), pp. 321-341. , DOI 10.1016/j.jaridenv.2004.11.015; Walker, B.H., Janssen, M.A., Rangelands, pastoralists and governments: Interlinked systems of people and nature (2002) Philosophical Transactions of the Royal Society B: Biological Sciences, 357 (1421), pp. 719-725. , DOI 10.1098/rstb.2001.0984; Wessels, K.J., Prince, S.D., Malherbe, J., Small, J., Frost, P.E., VanZyl, D., Can human-induced land degradation be distinguished from the effects of rainfall variability? A case study in South Africa (2007) Journal of Arid Environments, 68 (2), pp. 271-297. , DOI 10.1016/j.jaridenv.2006.05.015, PII S014019630600190X; West, N.E., Biodiversity of rangelands (1993) Journal of Range Management, 46 (1), pp. 2-13; White, R.P., Murray, S., Rohweder, M., (2000) Pilot Analysis of Global Ecosystems, , Grassland ecosystems. World Resource Institute, Washington, D.C., USA; Ji, Y.Z., Wang, Y., Zhao, X., Xie, G., Zhang, T., Grassland recovery by protection from grazing in a semi-arid sandy region of northern China (2005) New Zealand Journal of Agricultural Research, 48 (2), pp. 277-284; Zhao, W.Y., Li, J.L., Qi, J.G., Changes in vegetation diversity and structure in response to heavy grazing pressure in the northern Tianshan Mountains, China (2007) Journal of Arid Environments, 68 (3), pp. 465-479. , DOI 10.1016/j.jaridenv.2006.06.007, PII S0140196306002308

PY - 2012/3

Y1 - 2012/3

N2 - The non-equilibrium concept of rangeland dynamics predicts that the potential for grazing-induced degradation is low in rangelands with relatively variable precipitation. To date, evidence in support of the non-equilibrium concept has been inconsistent. Using a standardized protocol, including a newly developed global map of rainfall variability, we reviewed the incidence of degradation in relation to rainfall variability across 58 published studies. We distinguished between (1) zonal degradation (i.e., degradation independent of water and key resources), (2) degradation in the presence of key resources, and (3) degradation in the presence of water. For studies not affected by proximity to permanent water or key resources, we found strong support for the non-equilibrium concept for rangelands. Zonal degradation was absent at CV (coefficient of variation) values above 33%, which has been proposed as a critical threshold. Grazing degradation was almost entirely restricted to areas with relatively stable annual precipitation as expressed by a low CV, or to rangelands with key resources or water points nearby. To better understand rangeland dynamics, we recommend that future studies use globally comparable measures of degradation and rainfall variability. Our work underlines that rangelands with relatively stable rainfall patterns, and those with access to water or key resources, are potentially vulnerable to degradation. Grazing management in such areas should incorporate strategic rest periods. Such rest periods effectively mimic natural fluctuations in herbivore populations, which are a defining characteristic of non-degraded rangelands occurring under highly variable precipitation regimes.

AB - The non-equilibrium concept of rangeland dynamics predicts that the potential for grazing-induced degradation is low in rangelands with relatively variable precipitation. To date, evidence in support of the non-equilibrium concept has been inconsistent. Using a standardized protocol, including a newly developed global map of rainfall variability, we reviewed the incidence of degradation in relation to rainfall variability across 58 published studies. We distinguished between (1) zonal degradation (i.e., degradation independent of water and key resources), (2) degradation in the presence of key resources, and (3) degradation in the presence of water. For studies not affected by proximity to permanent water or key resources, we found strong support for the non-equilibrium concept for rangelands. Zonal degradation was absent at CV (coefficient of variation) values above 33%, which has been proposed as a critical threshold. Grazing degradation was almost entirely restricted to areas with relatively stable annual precipitation as expressed by a low CV, or to rangelands with key resources or water points nearby. To better understand rangeland dynamics, we recommend that future studies use globally comparable measures of degradation and rainfall variability. Our work underlines that rangelands with relatively stable rainfall patterns, and those with access to water or key resources, are potentially vulnerable to degradation. Grazing management in such areas should incorporate strategic rest periods. Such rest periods effectively mimic natural fluctuations in herbivore populations, which are a defining characteristic of non-degraded rangelands occurring under highly variable precipitation regimes.

KW - Climatic variability

KW - Degradation

KW - Drylands

KW - Grazing

KW - Rainfall

KW - Rangeland management

KW - climate variation

KW - environmental degradation

KW - global perspective

KW - grazing management

KW - herbivore

KW - precipitation assessment

KW - rainfall

KW - rangeland

KW - vulnerability

KW - Ecosystems Research

KW - Environmental planning

UR - http://www.scopus.com/inward/record.url?scp=84859531732&partnerID=8YFLogxK

U2 - 10.1890/11-0802.1

DO - 10.1890/11-0802.1

M3 - Journal articles

VL - 22

SP - 393

EP - 399

JO - Ecological Applications

JF - Ecological Applications

SN - 1051-0761

IS - 2

ER -

DOI