Question

I need help with a and b please.

ma No Spac... Heading 1 Heading 2 Title Font Paragraph Styles BIO 300 Ecology May 12, 2020 11. As a glacier moves forward or retreats, it leaves behind a mound or ridge of rocky debris known as a moraine (see photo below). Moraines are eventually colonized by plants. Lateral morame of the Calleque Glacier of the San Lorenzo Icefield in central Patagonia, South Amend Photos Martin 118.(2 pointsy with regard to the establishment of vegetation, what type of succession is present on moraines lib. 12 points) Nitrogen-fixing species (Dryas and Alder colonize moraines. Consider the diagram below. What model of

for ecology

Answer 1

11a.By looking at the moraines of different age such as the youngest moraines are populated with bacteria fungi and photosythetic micro organism, and slighly older moraines that have already gone through the earlier stage of succession have lichens mosses and few species of rooted herbs, ecologist sugessted that succession in moraines is primary succession.that when succession begins there is lack of living organism.

11b. Because of the absence of the nitrogen only a few plants can grow in moraines. In the case of Glacier Bay two plants that will grow are herbaceous plants, Dryas and Alder. Both have nitrogen fixing bacteria in nodules on the roots. Nitrogen fixing Alder and Dryas improve the soil, As soil condition improve Alder stands are invaded by spruce. Spruces then outcomplete and displace the Alders and Dryas. If the local climate does not change dramatically, a stable community dominate (Spruces) is likely to persist for many centuries. Such model is called temporal pattern of succession.