The Wild Mega-Grazers Maintaining Vegetation Assemblages in Grassland ecosystems are Under Threats : A Systematic Review on Grassland Ecosystems Across the Globe

IJEP 43(3): 219-226 : Vol. 43 Issue. 3 (March 2023)

Dipesh Raj Pant1, Kuaanan Techato2*, Siriporn Pradit1, Saroj Gyawali1 and Binod Baniya2

1. Prince of Songkla University, Faculty of Environmental Management, Hat Yai, Songkhla – 90110, Thailand
2. Tribhuvan University, Faculty of Environmental Science, Department of Environmental Science, Patan Multiple Campus, Kirtipur – 44618, Nepal


Grazing is one of the predominant human activities taking place today inside protected areas, with both direct and indirect effects on the vegetation community. The grassland vegetation diversity may enhance by the large herbivores as they are less selective in feeding impact on dominant plant species. Conservation of large herbivores is significant in the protected areas to maintain grassland vegetation. The study design and comprehensive literature were analyzed from 368 published literatures. A total of 13 articles were included, following the reporting standards for systematic evidence ssyntheses (RoSES) guidelines. Two independent reviewers carried out a systematic evaluation of the existing literature on The Wild Mega Grazers Maintain Vegetation Assemblage in Grassland and the threats. A total of 368 papers were identified, but after intensive screening only 13 met the inclusion criteria and were reviewed. From this review, the large herbivores were understood as an excellent group for the macro-ecological study. They occur in a diverse array of habitats, exhibit considerable morphological variation, have extensive distributions and shape ecosystem function through the effects of grazing. Grazing animals are considered a tool to maintain the biodiversity of grassland. However, the grazers are being threatened due to climate change issues, which raises concerns about their survival. The decreasing of forage grass species due to recurring floods have caused shrinking of habitat, spreading of invasive species, ultimately reducing the native palatable plants, such as Agropyron cristatum, Agrostis trini, Cleistogenes squarrosa, Elymus chinensis, Poa attenuata, Stipa krylovii as food items of the wild grazers. In addition, illegal grazing and cutting of grass are also challenging aspects which could have developed issues, such as grassland management.


Grassland ecosystem, Mega herbivores, Threat, Relocation, Human settlements, Park people conflict


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