I am studying the impact of trampling on the growth pattern of American sea rocket, Cakile edentula, at Airforce Beach in the Comox Valley. I chose to explore the first 500 meters of beachfront starting from the northern beachside parking lot. As you can see from the map below, Airforce beach is bordered to the north by a headland from which people park and access the beach. Additional parking is offered up above, with people walking across the dune to access the beach.
Initially I had some difficulties in deciding how to collect my data. I knew that I would need to utilize some sort of systematic sampling but was initially unsure how to ensure random sampling. I ended up with the following strategy:
I used systematic grid sampling across the foredune region. I chose a plot size of 5 x 5 ft due to the fact that the foredune region along airforce beach is sparsely populated with Cakile edentula, therefore I wanted to be able to capture a representative sample. I chose my starting point by using a random number generator between 1 and 50 to determine the distance in meters from the entry point to the beach that I would begin plot sampling. Each additional plot sample was measured 50 meters away for a total of 11 plot samples. I repeated this process 5 times, each time using a random number generator to determine the sampling start point.
I recorded two pieces of information in each plot sample. First, I did a complete count of Cakile edentula within the plot parameters. Secondly, I recorded the number of species that were within 6 inches of what I am calling a protective structure.
I was surprised by the fact that sampling of even a small area can be incredibly time consuming. Also, having little experience in doing field research I was always second guessing myself and wondering how accurately my counting and measuring was.
Also I was using a measuring tape to mark everything. I feel that it would be easier to simply use a 6 inch piece of wood to determine if Cakile edentula is growing in the open or not. Also, with reference to my plot size (5×5 ft) I was marking and measuring and this seemed to be incredibly time consuming. Going forth I will bring a square and 4-five foot lengths of wood to box out my plot to make the process quicker.