Bioscience Evidence 2024, Vol.14, No.2, 69-80 http://bioscipublisher.com/index.php/be 70 interactions and feedback mechanisms that govern savanna ecosystems. By doing so, it seeks to inform appropriate management strategies that can help maintain ecosystem integrity, biodiversity, and human livelihoods in the face of ongoing environmental changes. The scope of the study encompasses a wide range of topics, including the impact of human activities, climate change, and land use on savanna ecosystems, as well as the role of different plant and animal species in shaping the energy flow and trophic dynamics within these ecosystems. 2 Characteristics of African Savanna Ecosystems 2.1 Geographical distribution African savannas are primarily located in the tropical and subtropical regions of the continent, spanning across countries such as Kenya, Tanzania, South Africa, and Botswana. These ecosystems are characterized by a mix of grasslands and scattered trees, creating a unique landscape that supports a diverse range of flora and fauna. The distribution of savannas is largely influenced by climatic factors, particularly rainfall patterns, which vary significantly across different regions (Fundisi et al., 2022). The spatial distribution of savanna environments is also shaped by historical disturbances and species interactions, which can lead to variations in vegetation types even within similar climatic zones (Higgins et al., 2023; Shan, 2024). 2.2 Climate and environmental conditions The climate of African savannas is typically marked by distinct wet and dry seasons, with rainfall being a critical determinant of vegetation patterns. Savannas receive moderate to low annual rainfall, usually between 500 to 1 500 mm, which is sufficient to support grasses but not dense forests (Martens et al., 2020; Higgins et al., 2023). The seasonal precipitation influences the structure and composition of plant communities, with grasses dominating during the wet season and trees becoming more prominent in the dry season (Ferreira et al., 2022). Additionally, the savanna climate is subject to significant variability, both spatially and temporally, which can lead to changes in woody plant species compositions and overall ecosystem dynamics (Ma et al., 2020; Fundisi et al., 2022). Figure 1 illustrates the climatic suitability surfaces for major plant growth forms across Africa, highlighting the spatial distribution of different vegetation types influenced by climatic factors (Higgins et al., 2023). 2.3 Vegetation and plant diversity African savannas are known for their heterogeneous vegetation, comprising a mix of woody and herbaceous plants. This diversity is influenced by a combination of climatic conditions, soil types, and human activities. The vegetation structure includes a variety of grasses, shrubs, and trees, with species composition varying across different regions and environmental gradients (Muumbe et al., 2021; Western et al., 2021). Remote sensing studies have highlighted the functional diversity of savanna vegetation, emphasizing the importance of monitoring woody plant species to inform sustainable biodiversity management. Furthermore, traditional management practices by indigenous communities have played a significant role in maintaining the diversity and structure of savanna ecosystems, promoting species that are beneficial for human use and ecosystem health (Ferreira et al., 2022). The plant diversity in African savannas is also crucial for ecosystem functions such as carbon storage and primary productivity. Studies have shown that higher tree species diversity is associated with increased aboveground biomass and structural diversity, which in turn supports greater ecosystem resilience and function. However, land use changes, such as agricultural expansion, have led to significant reductions in plant biodiversity and carbon storage, highlighting the need for sustainable land management practices to preserve these vital ecosystems (Balima et al., 2020; Godlee et al., 2021). 3 Energy Flow in African Savannas 3.1 Primary production Primary production in African savannas is driven by photosynthesis, where plants convert solar energy into biomass. This process is influenced by various factors, including water availability, soil fertility, and climatic conditions. Key primary producers in these ecosystems include grasses and trees, which exhibit distinct phenological characteristics and contribute differently to the ecosystem's gross primary production (GPP) (Higgins et al., 2023). Studies have shown that GPP in savannas can vary significantly with rainfall and other
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