Tuesday marks the first day that I have ever collected my own data for a field research project. Years of research papers and reading research studies has given me some idea of the fundamentals of systematic data collection, but nothing compares to the real world experience my research partner Miyako and I conducted this past week. After days of planning our own research questions and refining them into fully fledged methodologies, we decided to work on her project, where we collected data at La Selva to find how disturbances both human and otherwise impact the amount of invasive species in a given area. The first day at La Selva, we were informed about how particularly invasive the Pink Banana of the Musa (banana) genus is at La Selva. One question I asked our lovely tour guide Kenneth was how bad invasive species were, and he said that these species were more of an issue in the newer secondary forests. Little did I know that this answer would come to be a helpful side note to the research and background of this project to come.
During our first meeting with Dr. W after coming together on the research project, we decided to tackle more easily recognizable invasive species that could be found throughout La Selva: The Pink Banana, that has been used in edible gardens and ornamentally, the species of rapidly spreading bamboo (there is no native species of bamboo in this particular region of (Costa Rica), and lastly the cultivated crop Cacao. All of these species have varying levels of invasive status, but particularly the bamboo and pink banana seem to be of great concern in protected forests. Banana trees are not native to this continent at all but have been introduced as a cash crop from tropical Asia. To add a degree of randomness, we decided on doing a 100 meters on, 50 meters off system, where we would stop looking for species at this uneven interval. We used a GPS mapping tool that Eric let us borrow to track our meters walked and do this random sampling method. After an afternoon of playing around on the GPS, I was finally able to figure our how to start and stop recording meters walked. Although this worked great for our first set of data, our advisors were concerned that this method would probably not be as accurate as using the meter marks that were available for most of the trails. Additionally, I made multiple mistakes in the charging of the device that would have been detrimental had these trails not been well marked, as well as us having the other method for tracking meters traversed with the GIS component of our project.
On Tuesday 6/6 we had one final talk with Dr. W and went to conduct our first transects in actively human developed areas. We walked the same road that we walked on due to the tree falling on the road on the way back from the pineapple farm all the way to the highway where we walked past houses and seemingly naturally retaken pasture fields on the way to the other entrance to the Research station by the Zompopa houses. Along this trail of human developed land we were surprised to see plenty of all of the species we were looking for, by order of biomass we saw: A large forest of bamboo encompassing at least an area of 75 meters wide and 50 meters deep, reaching the same height as the canopy cover, next we saw over 30 individual pink banana plants, and 8 cacao trees. Traversing 2800 meters total, using our collection method we collected 14 transects of data.
The next day we searched the youngest patch of secondary forest in La Selva, marked at 20-39 years old 5 years ago. We chose this to be as close to a new secondary forest as possible to differentiate from the old growth to come the next day. While we definitely saw less plants per distance traversed, the secondary forest patch we walked to was quite far down the trail (over three miles) that we were walking in the heat, so we did not end up collecting quite as much data on this section this day as we did the human developed area. In this path we took, we decided to take CES to STR which cut down on the mileage as well as taking us through some old growth forest to collect data on on the way. Wednesday was the first day we ran into troubles with the GPS, an oversight on my behalf. Upon taking the GPS out once we reached the first set of old growth I realized that the battery had gotten to one bar and it did not last far into the forest. We switched to using the trail signs to implement our on off periods as a substitute that we were considering anyway.
Thursday and Friday was devoted to getting mostly data on old growth, as well as collecting some more new sec. forest to get a few more transects on this data set. Because I realized that we were leaving soon, I was excited to go deeper into the old forest on dirt trails to see the even less human disturbed places and had a really great 4 mile hike despite the blisters that had been plaguing me throughout our research days. Surprisingly, even including the 15 extra transects I collected beyond Miyako and I’s data collecting hike in the morning we did not see a single invasive species in any of the old growth designated forest. I was very happy with how our research turned out, and our systematic method seems to have given us accurate data to translate onto excel for data analysis and Arcgis for plotting the collected coordinates.
Leave a Reply