Final answer:
Environmentalists and researchers such as Clinton N. Jenkins and McKenzie Johnson, along with local organizations like The Wilderness Society, are actively involved in the conservation of grasslands and savannahs. They study and manage the delicate balance of these ecosystems, focusing on the role of disturbances like fire and the impact of grazing on biodiversity and structure of savannah habitats.
Step-by-step explanation:
Environmentalists focusing on grasslands and savannah ecosystems play a crucial role in ensuring these biodiverse regions are conserved. Savannas, such as those in Taita Hills Wildlife Sanctuary in Kenya, are grass-dominated landscapes interspersed with small woodlands, as seen in Mount Archer National Park in Queensland, Australia. Conservationists like Clinton N. Jenkins from Duke University and McKenzie Johnson from the Wildlife Conservation Society are influential figures who contribute to understanding and preserving the delicate balance of these ecosystems. Local organizations in Australia, such as The Wilderness Society and Landcare groups, actively engage in managing and protecting grassland and savannah habitats.
Environmentalists often highlight the significance of disturbances like fire in maintaining the tree-grass balance in savannas, which can otherwise progress towards closed canopy forests as suggested by Sankaran et al. (2005). The interactions between fire frequency, grazing by wildlife, and herbivory are essential factors influencing the structure and diversity of these ecosystems. Sustainable management practices, including controlled burning and grazing, are employed to prevent woody plant encroachment and maintain the savannah's open structure, as seen in Queensland's grassland conservation efforts.
In the broader context of global environmental change, savannahs are also affected by shifts in atmospheric conditions. The work of researchers such as Sankaran et al. and Werner highlights the impact of changing fire regimes and CO₂ levels on tree biology and grass productivity, which have implications for fire disturbance frequencies in the savannah landscape.