What are Coastal Dunes?
Coastal dunes form when wet sand is deposited along the coast and dries out and is blown along the beach.
Dunes form where the beach is wide enough to allow for the accumulation of wind-blown sand, and where prevailing onshore winds tend to blow sand inland. The three key ingredients for coastal dune formation are a large sand supply, winds to move said sand supply, and a place for the sand supply to accumulate. Obstacles—for example, vegetation, pebbles, and so on—tend to slow down the wind and lead to the deposition of sand grains. Models of coastal dunes suggest that their final equilibrium height is related to the distance between the water line and where vegetation can grow. Coastal dunes can be classified by where they develop or begin to take shape. Dunes are commonly grouped into either the Primary Dune Group or the Secondary Dune Group. Primary dunes gain most of their sand from the beach itself, while secondary dunes gain their sand from the primary dune. Different locations around the globe have dune formations unique to their given coastal profile. Over the course of time, coastal dunes may be impacted by hurricanes or other intense storm activity, dependent on their location. Recent work has suggested that coastal dunes tend to evolve toward a high or low morphology depending on the growth rate of dunes relative to storm frequency. During a storm event, dunes play a significant role in minimizing wave energy as it moves onshore. As a result, coastal dunes, especially those in the foredune area affected by a storm surge, will retreat or erode.
What is Humus?
Humus is dark, organic matter that forms in soil when plant and animal matter decays. 
When plants drop leaves, twigs, and other material to the ground, it piles up. This material is called leaf litter. When animals die, their remains add to the litter. Over time, all this litter decomposes. This means it decays, or breaks down, into its most basic chemical elements. Many of these chemicals are important nutrients for the soil and organisms that depend on soil for life, such as plants. The thick brown or black substance that remains after most of the organic litter has decomposed is called humus.
Logging Tasks:
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Are the dunes at the GZ considered to be in the Primary Dune Group, the Secondary Dune Group, or both?
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What conditions are found at the GZ that dunes need in order to form? Are all three of these conditions met at GZ? Explain.
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Using the infographics provided in the description and your observations of the dunes, what type of dune is seen at the GZ (mature dune, grey dune, yellow dune, foredune, or embryo dune)?
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What is the height of the dunes?
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Estimate the percentage of humus seen on the dunes. Is it: <1%,1-10%, or >10% of humus ?
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Was there any vegetation on the dunes at the GZ?
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Sources:
https://www.nationalgeographic.org/encyclopedia/humus/#:~:text=Powered%20by-,Humus%20is%20dark%2C%20organic%20material%20that%20forms%20in%20soil%20when,remains%20add%20to%20the%20litter.
https://en.wikipedia.org/wiki/Humus
https://www.internetgeography.net/topics/how-are-sand-dunes-formed/
https://en.wikipedia.org/wiki/Dune#Coastal_dunes
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