1.Decomposers -- major impact in nutrient cycling in the ecosystem.
2.Symbiotic relationships with other organisms, e.g., mycorrhizae and lichens -- major impacts on ecosystem.
Economic:
3.Culinary arts -- treasured for flavor even though of low nutrient content.
4.Pathenogenic -- plants and animals.
5.Yeast -- fermentation, bread-making, cheese, biotechnology.
6.Medicinal -- antibiotic properties.
7.Decomposition -- dry rot can cause structural problems.