Editing Overgrazing (section)

==Ecological impact ==
{{Further|Land degradation}}
Overgrazing typically increases [[soil erosion]].<ref>C. Michael Hogan (2009). "[http://www.eoearth.org/article/Overgrazing Overgrazing]" ({{Webarchive|url=https://web.archive.org/web/20100711111015/http://www.eoearth.org/article/Overgrazing |date=2010-07-11 }}). ''Encyclopedia of Earth''. Sidney Draggan, topic ed.; Cutler J. Cleveland, ed. Washington, D.C.: National Council for Science and the Environment.</ref>

With continued overutilization of land for grazing, there is an increase in degradation. This leads to poor soil conditions that only [[Deserts and xeric shrublands|xeric]] and early [[Primary succession|successional species]] can tolerate.<ref name="Ecosystem modification created by p">{{cite journal |last1=Fuls |first1=E.R. |title=Ecosystem modification created by patch-overgrazing in semi-arid grassland |journal=Journal of Arid Environments |date=1992 |volume=23 |issue=1 |pages=59–69 |bibcode=1992JArEn..23...59F |doi=10.1016/S0140-1963(18)30541-X}}</ref> A [[meta-analysis]] of 148 studies found that the value of most ecosystem functions declines with increasing grazing intensity and that increasing aridity weakens positive impacts of light grazing.<ref>{{Cite journal |last1=Niu |first1=Weiling |last2=Ding |first2=Jingyi |last3=Fu |first3=Bojie |last4=Zhao |first4=Wenwu |last5=Eldridge |first5=David |date=2025-02-01 |title=Global effects of livestock grazing on ecosystem functions vary with grazing management and environment |url=https://www.sciencedirect.com/science/article/abs/pii/S0167880924004146 |journal=Agriculture, Ecosystems & Environment |volume=378 |pages=109296 |doi=10.1016/j.agee.2024.109296 |bibcode=2025AgEE..37809296N |issn=0167-8809|url-access=subscription }}</ref>

[[Native plant]] [[grass]] species, both individual [[bunch grass]]es and in [[grassland]]s, are especially vulnerable. For example, excessive browsing by [[white-tailed deer]] can lead to the growth of less preferred species of grasses and ferns or non-native plant species<ref>Côté, S. D., Rooney, T. P., Tremblay, J. P., Dussault, C., & Waller, D. M. (2004). "Ecological impacts of deer overabundance". ''Annu. Rev. Ecol. Evol. Syst.'', 35, 113-147.</ref> that can potentially displace native, woody plants, decreasing the biodiversity.<ref>Baiser, B., [[Julie Lockwood|Lockwood, J. L.]], La Puma, D., & Aronson, M. F. (2008). "A perfect storm: two ecosystem engineers interact to degrade deciduous forests of New Jersey". ''Biological Invasions'', 10(6), 785-795.</ref><ref>Horsley, S. B., Stout, S. L., & DeCalesta, D. S. (2003). White‐tailed deer impact on the vegetation dynamics of a northern hardwood forest. Ecological applications, 13(1), 98-118.</ref>

Turning to the aquatic environment, Ling et al. (2015)<ref>{{Cite journal |last1=Ling |first1=S. D. |last2=Scheibling |first2=R. E. |last3=Rassweiler |first3=A. |last4=Johnson |first4=C. R. |last5=Shears |first5=N. |last6=Connell |first6=S. D. |last7=Salomon |first7=A. K. |last8=Norderhaug |first8=K. M. |last9=Pérez-Matus |first9=A. |last10=Hernández |first10=J. C. |last11=Clemente |first11=S. |last12=Blamey |first12=L. K. |last13=Hereu |first13=B. |last14=Ballesteros |first14=E. |last15=Sala |first15=E. |date=2015-01-05 |title=Global regime shift dynamics of catastrophic sea urchin overgrazing |journal=Philosophical Transactions of the Royal Society B: Biological Sciences |language=en |volume=370 |issue=1659 |pages=20130269 |doi=10.1098/rstb.2013.0269 |issn=0962-8436 |pmc=4247405}}</ref> have documented the phenomenon of catastrophic [[sea urchin]] overgrazing and its role in [[marine ecosystem]] regime shifts. Their study underscores the urgent need for effective management and conservation strategies to mitigate the profound ecological impacts of overgrazing, highlighting the issue's global scope. Similarly, on the Mongolian steppes, Liu et al. (2013)<ref>{{Cite journal |last1=Liu |first1=Yi Y. |last2=Evans |first2=Jason P. |last3=McCabe |first3=Matthew F. |last4=Jeu |first4=Richard A. M. de |last5=Dijk |first5=Albert I. J. M. van |last6=Dolman |first6=Albertus J. |last7=Saizen |first7=Izuru |date=2013-02-25 |title=Changing Climate and Overgrazing Are Decimating Mongolian Steppes |journal=PLOS ONE |language=en |volume=8 |issue=2 |pages=e57599 |doi=10.1371/journal.pone.0057599 |doi-access=free |issn=1932-6203 |pmc=3581472 |pmid=23451249|bibcode=2013PLoSO...857599L }}</ref> found that approximately 60% of vegetation decline could be attributed to climate factors, with the rest significantly influenced by increased goat density due to overgrazing. This points to a complex interplay between [[climate change]] and grazing practices in ecosystem degradation.

Further expanding our understanding, Stevens et al. (2016)<ref>{{Cite journal |last1=Stevens |first1=Nicola |last2=Erasmus |first2=B. F. N. |last3=Archibald |first3=S. |last4=Bond |first4=W. J. |date=2016-09-19 |title=Woody encroachment over 70 years in South African savannahs: overgrazing, global change or extinction aftershock? |journal=Philosophical Transactions of the Royal Society B: Biological Sciences |language=en |volume=371 |issue=1703 |pages=20150437 |doi=10.1098/rstb.2015.0437 |issn=0962-8436 |pmc=4978877 |pmid=27502384}}</ref> investigated [[Woody plant encroachment|woody encroachment]] in South African [[Savanna|savannahs]] over a 70-year period, identifying overgrazing, global changes, and the ecological effects of [[megafauna]] extinction as key factors. Their findings shed light on the multifaceted drivers behind changes in savannah ecosystems. Echoing this theme of alternative strategies to combat overgrazing, Kriegisch et al. (2019)<ref>{{Cite journal |last1=Kriegisch |first1=N. |last2=Reeves |first2=S. E. |last3=Flukes |first3=E. B. |last4=Johnson |first4=C. R. |last5=Ling |first5=S. D. |date=2019-07-01 |title=Drift-kelp suppresses foraging movement of overgrazing sea urchins |url=https://doi.org/10.1007/s00442-019-04445-6 |journal=Oecologia |language=en |volume=190 |issue=3 |pages=665–677 |doi=10.1007/s00442-019-04445-6 |pmid=31250188 |bibcode=2019Oecol.190..665K |issn=1432-1939|url-access=subscription }}</ref> demonstrated how drift-[[kelp]] availability could reduce the foraging movement of overgrazing sea urchins, suggesting that alternative food sources may significantly influence grazing behaviors and aid in managing marine ecosystem pressures.

In a similar vein, the research by Cai et al. (2020)<ref>{{Cite journal |last1=Cai |first1=Yurong |last2=Yan |first2=Yuchun |last3=Xu |first3=Dawei |last4=Xu |first4=Xingliang |last5=Wang |first5=Chu |last6=Wang |first6=Xu |last7=Chen |first7=Jinqiang |last8=Xin |first8=Xiaoping |last9=Eldridge |first9=David J. |date=2020-03-01 |title=The fertile island effect collapses under extreme overgrazing: evidence from a shrub-encroached grassland |url=https://doi.org/10.1007/s11104-020-04426-2 |journal=Plant and Soil |language=en |volume=448 |issue=1 |pages=201–212 |doi=10.1007/s11104-020-04426-2 |bibcode=2020PlSoi.448..201C |issn=1573-5036|url-access=subscription }}</ref> presents a stark example of the terrestrial impact of overgrazing, showing how the fertile island effect collapses under extreme conditions in shrub-encroached [[Grassland|grasslands]]. This case study emphasizes the critical need for sustainable grazing practices to protect soil health and maintain ecosystem functionality, further illustrating the wide-reaching consequences of overgrazing across diverse habitats.