Final answer:
Issues affecting the life support chain involve impacts on biogeochemical cycles of essential elements like carbon, nitrogen, and oxygen. Disruptions in geological and biological processes can alter these cycles, resulting in environmental changes that affect life's distribution.
Step-by-step explanation:
Various issues can impact the Fundamental Elements of Life Support Chain, including the cycles of the biogenic elements carbon, nitrogen, hydrogen, oxygen, phosphorus, and sulfur. These elements are part of biogeochemical cycles and are essential for life as they participate in a multitude of biological and chemical processes.
Energy flows directionally through ecosystems and is eventually lost as heat, but these elements are conserved and recycled. Geologic processes such as weathering, erosion, water drainage, and the subduction of continental plates, alongside biological functions like the role of microorganisms, govern the availability and distribution of these elements.
Disruptions to these cycles through human activities or natural changes can influence the habitability of an environment, potentially affecting the distribution of life.