What are 3 symbiotic relationships in the cold desert?

In cold desert ecosystems, three notable symbiotic relationships include:

1. Mutualism between lichens and fungi: Lichens, consisting of a fungal partner and a photosynthetic partner (alga or cyanobacterium), thrive in harsh conditions by combining their strengths for nutrient acquisition and moisture retention.

2. Commensalism between burrowing animals and vegetation: Animals like rodents dig burrows that provide shelter, while the vegetation above benefits from the aeration of the soil and improved water drainage, though the plants are not directly affected by the animals' presence.

3. Parasitism between desert plants and their pathogens: Certain desert plants may host parasitic fungi or bacteria that extract nutrients, harming the plant while benefiting the parasite, which can thrive in the nutrient-scarce environment.