This topic explores the levels of organisation within ecosystems, including populations, communities, and the abiotic and biotic factors that influence them. It also covers the principles of material cycling, such as the carbon and water cycles, and the importance of biodiversity, including human impacts and conservation strategies.
Ecosystems are dynamic systems where living organisms (biotic factors) interact with each other and their non-living environment (abiotic factors). In WJEC GCSE Combined Science, you will explore how energy flows through food chains and webs, how nutrients cycle, and how populations change over time. Understanding ecosystems is crucial because it helps us appreciate the delicate balance of nature and the impact of human activities on biodiversity.
This topic covers key processes such as photosynthesis, respiration, and decomposition, which drive the cycling of carbon and water. You will also learn about adaptations of organisms to their habitats, competition, and predator-prey relationships. Ecosystems are not isolated; they are connected through global cycles, making this topic essential for understanding environmental issues like climate change and conservation.
Mastering ecosystems will prepare you for questions on fieldwork techniques, such as using quadrats and transects to estimate population sizes. It also links to other topics in Combined Science, including genetics (variation and adaptation) and chemistry (carbon cycle). By the end, you should be able to explain how changes in one part of an ecosystem can ripple through the whole system.
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