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This MyWorld map shows the relation between the type of substrate in the Emerald Bay and Howlings Landing area and the kelp also within that area.
Introduction:From October 15 until October 19, the PCDS 8th grade class went to Howland’s Landing, on Catalina Island, to study the ocean. During our weeklong stay, we went snorkeling, kayaking, hiking, climbing, and engaged in many other activities. We learned about kelp and the entire ecosystem based upon it. The importance of kelp to the ecosystem led us to our research question; does the depth of the sea floor, and the substrate of the sea floor, affect giant kelp? Substrate is the sand and rocks that can be found on the sea floor. Kelp is vital to the ecosystem of the ocean because it provides nutrients, homes, and protection to many types of sea creatures. It is important to plot where kelp grows, and in which conditions it grows best in, so humans can help to preserve and maintain kelp if it becomes endangered. To pursue our research question, we needed to learn more about the relationship between kelp and sea floor substrate. This study explains how the depth of the sea floor, and the substrate type of the sea floor, affect giant kelp. This paper will help scientists, students, and anyone else who is interested learn more involving the ocean floor and its effect on giant kelp. Giant kelp is one of the largest seaweeds in the world.
Research: Giant kelp, or Macrocystis pyrifera, is an ocean-dwelling seaweed found in coastal waters. It can grow to be over forty meters tall in clear water, and can exist in oceans up to a hundred feet deep. Each plant consists of a main stalk, with clusters of reproductive blades and buoyant gas balloons branching off from the main stalk. It is held to the seafloor by a holdfast, which is a cluster of root-like tendrils that intertwine with rocks on the seafloor.
Our research was centered around the effects of substrate and depth on the health of giant kelp. In other words, our question was: does the type of substrate and depth of an area factor into whether or not kelp can grow in a certain place? To answer this question, we used a variety of techniques, including GIS programs and combing a collection of kelp-related books for data. Before we left for Catalina Island, we read through several books in order to familiarize ourselves with kelp and the sea floor. We also assembled data layers and maps to find where the kelp beds and types of substrate were on the sea floor. When we arrived on the island, we took a more hands-on approach to our research. We surveyed an area of sea floor, containing a variety of depths and substrate types. This was accomplished through both kayaking on the surface and snorkeling underwater. We noted the substrate type and approximate depth of the areas that we passed over and the amount of kelp in those places. When we returned to Phoenix, we compiled our findings and assembled them into this report.
We found that the health of kelp is highly dependent on the type of substrate, but not as dependent on the depth. Kelp cannot grow on a sandy bottom, as it cannot get a solid footing early in life. Heavy boat traffic kills kelp, both directly as in propellers and fuel leakage, and indirectly through buoy lines and moorings, so there is very little to no kelp near harbors and ports. If the sea floor is covered in broken pieces of rock or large rough stone chunks, the kelp finds it very easy to get secure itself through its holdfast. Kelp in these areas will usually grow in close proximity to each other, and each plant will normally be healthy. Based on the above findings, it can be stated that giant kelp grows best and will survive for the longest period in areas of rocky sea floor, far from frequent boat traffic, and at a depth no deeper than 30 meters.
Conclusion: After researching about kelp and visiting the island of Catalina and studying the kelp there personally, we have concluded that kelp’s growth is not as much dependant on the depth it is at as much as what substrate it was holding on to. The kelp was growing well and flourishing in areas of the ocean where there was a sturdy and rough rocky bottom to hold on to, but where there was a sandy floor or a weak gravel the kelp couldn’t grow because it was either too shallow or had no where to attach itself. As far as future research on this topic, if we or someone could travel back to Catalina and take another look at the kelp we would probably look more at the relation to what substrate is at what depth. This way we could identify the relation between depth and substrate. This would help us determine where kelp would be able to grow. Following our stay at Catalina we hope to further improve our knowledge on this subject and the ocean in general.
Works Cited
McPeak, Ronald H. Dale A. Glantz. Carole R. Shaw. McPeak, Ronald H. Dale
A. Glantz. Carole R. Shaw. The Amber Forest: San Diego: Watersport Bpublishing,
inc, 1988
Connor, Judith and Charles Baxter. Kelp Forests. Monterey Bay Aquarium
Fondation, 1989.
“Kelp Forests.” Wikipedia. En.wikipedia.com.
