Describe the positive and negative interactions that affect populations in the tundra ecosystem?

Tundra ecosystems are ones which are some of the Earth's coldest and harshest, with few trees, low rainfall, high winds and often much snow, for example, the Arctic. Animals in tundra environments typically feed on shrubs and insects, polar bears, caribou, and Arctic foxes are species which live in such environments. Negative impacts are the fact that global warming is melting ice and these environments are dramatically changing, resulting in water levels rising greatly, and changing weather patterns, this is meaning that there are more green spaces, offering more potential for food and population growth among animals, but harming the ecosystem as it is, some species are affected negatively by this through becoming prey. As harsh climates, Tundra is not easy to live in with limited food access and cold temperatures, however, human pollution is naturally less in these environments.