Final answer:
Biotic factors refer to the living or once-living parts of an ecosystem, which in a forest include plants, animals, and decayed material. Producers and consumers play different roles in food chains, with plants producing their own food and animals consuming other organisms. Abiotic factors such as sunlight may change in an ecosystem due to events like the destruction of trees by disease.
Step-by-step explanation:
1. The best identifier for biotic factors in a forest environment is plants, animals, and decayed material including soil, dead trees, and bacteria. These components are either living or were once living, contributing to the living aspects of the ecosystem.
2. In a food chain, plants are called producers because they make their own food through photosynthesis, whereas animals are called consumers because they eat other organisms to obtain energy.
3. If a disease destroys all of the oak trees in an oak forest ecosystem, an expected change in abiotic factors might be the level of available sunlight. With the loss of tree canopy, more sunlight would penetrate to the forest floor, potentially altering the ecosystem.
Abiotic and biotic factors interact in numerous ways. For example, the temperature and moisture levels of a biome (abiotic factors) greatly influence the types of plants that can grow there, which in turn affects the types of herbivores and carnivores (biotic factors) that the vegetation can support.