The correct option for maintaining biodiversity in a managed ecosystem is C. Sustainable logging practices. Detailed Explanation

1. Understanding Biodiversity: Biodiversity refers to the variety of life in a particular habitat or ecosystem. It includes the diversity of species, genetic diversity within those species, and the variety of ecosystems themselves. Maintaining biodiversity is crucial for ecosystem resilience, productivity, and the provision of ecosystem services.
2. Evaluating the Options:
3. A. Monoculture farming: This practice involves growing a single crop species over a large area. While it can be economically efficient, it significantly reduces biodiversity. Monocultures are more susceptible to pests and diseases, which can lead to increased pesticide use and further harm to the ecosystem. This practice does not support a diverse range of species and can lead to soil degradation and loss of habitat.
4. B. Habitat fragmentation: This occurs when large habitats are broken into smaller, isolated patches, often due to human activities like urban development or agriculture. Fragmentation can lead to a decrease in species diversity, as smaller habitats may not support viable populations of certain species. It also disrupts migration patterns and can lead to inbreeding and genetic drift, further threatening biodiversity.
5. C. Sustainable logging practices: This approach involves managing forest resources in a way that meets current needs without compromising the ability of future generations to meet theirs. Sustainable logging practices include selective logging, maintaining buffer zones, and ensuring that logging does not exceed the forest's natural regeneration capacity. These practices help preserve the ecosystem's structure and function, allowing for a diverse range of species to thrive. By maintaining habitat integrity and promoting regeneration, sustainable logging can support biodiversity.
6. D. Urban development: Urbanization typically leads to habitat destruction, pollution, and increased human-wildlife conflict. While urban areas can incorporate green spaces, the overall impact of urban development is often negative for biodiversity. It tends to fragment habitats and reduce the area available for wildlife, leading to declines in species populations.
7. Why Other Options Are Weaker:
8. Monoculture farming is detrimental to biodiversity as it eliminates the variety of species that can coexist in an ecosystem.
9. Habitat fragmentation directly harms biodiversity by isolating species and reducing their habitats.
10. Urban development generally leads to habitat loss and increased pressure on remaining ecosystems, making it a poor choice for maintaining biodiversity.

Summary of Key Points

• Biodiversity is essential for ecosystem health and resilience.
• Sustainable logging practices help maintain biodiversity by allowing ecosystems to regenerate and supporting a variety of species.
• Monoculture farming, habitat fragmentation, and urban development all negatively impact biodiversity.
• Effective management of ecosystems requires practices that support the diversity of life, such as sustainable resource use.

By understanding these concepts, students can appreciate the importance of sustainable practices in maintaining biodiversity within managed ecosystems.