Evan Raczkowski Thursday, November 20th, 2008
Lab 5
Depicted in the following graph is the relationship between various farm characteristics and the percent guava by farm:
As percent guava increases: Farms
As percent guava decreases: Farms
As percent guava increases: Farm fields
As percent guava decreases: Farm fields
There are very notable proximity relationships that exist between percent guava by field and roads/buildings. For the most part, it is very interesting to note that there is not a large percentage of guava in fields that are directly adjacent to farms and buildings. As you can see in the graphic provided (see Graphic_A in the ‘Graphics’ folder), the roads and buildings mostly exist around the perimeter of the farm fields (with exception to the northeast corner of our study area). It is only in the southern portion of our study area that a large amount of guava trees are adjacent to roads. Also very notable is the fact that almost no guava exists near buildings. This discovery was somewhat surprising at first, as I would expect there to be a great deal of guava trees near commonly-traveled paths. However, this visual representation helps to show how farmers in the region try their best to eradicate the invasive guava plant. Furthermore, they are more able to get rid of guava trees around buildings and roads because they likely can get heavy machinery to these areas more easily (with the roads). Furthermore, they destroy the guava trees near their buildings because of their proximity. In the interior of our study area, it is clear that there is a high percentage of guava in the farm fields, likely because not many roads nor buildings exist in these areas (it is difficult to get heavy machinery to these areas without the roads).
As a general rule, there is a direct correlation between abandonment and the percentage of guava in a farm. In the farms that are very active, there appears to be a very low percentage of guava. In the farms that are partially abandoned, there seems to be a moderate percentage of guava, with few exceptions (in the southern portion of rthe study area a partially abandoned farm is almost entirely guava while in the western portion there is a partially abandoned farm that is almost devoid of guava). In the one farm that is officially ‘abandoned’ in my study area, there is actually a monstrous amount of guava. This realization was no surprise, as there is obviously going to be a higher percentage of guava in farms that are underutilized or do not retain that much human activity. On the other hand, farms that retain a great deal of human activity and are used for pasturizing and farming are obviously going to have a lower percentage of guava. See Graphic_B, Graphic_C and Graphic_D for visual representation (make sure to see *notes at the bottom of each jpeg).
There were interesting guava tree clustering patterns in the our study area. For example, there seemed to be large very concentrated clusters of guava trees on one side of a property line while there would be absolutely no guava trees on the other side. This shows the different land-use practices that individual farm owners adjacent to each other employ. Furthermore, there are also many guava tree lines, showing that sometimes these tree lines may exist between different farming plots. For instance, one farmer could use these guava tree lines to separate different types of farm plots (using guava tree lines to separate coffee plants and banana trees, for instance). It was also notable that there were more individual clusters in areas that are used heavily by humans and less clusters/giant masses of guava trees in more abandoned areas. See Graphic_E for visual representation.
It is clearly evident that there is a direct correlation between guava in the park and it’s distance from the agricultural zone. In other words, directly outside of the agricultural zone, there seems to be a higher percentage of guava. As you move further and further away from the agricultural zone, there seems to be a lower percentage of guava trees. This statistics clearly indicates that areas of higher human use (agricultural zones) contain more invasive plant species such as guava trees. This is likely due to the fact that high human trafficking allows for the transfer of guava seeds, allowing the trees to spread more rapidly and expansively. Furthermore, the animals present in these agricultural zones such as cattle, etc. transfer the seeds through feces and moving around as well.These farm animals do not exist in the park, therefore there is less guava invasion in this area.
There is an interesting correlation between guava distribution in the park and guava distribution bordering the park. There is a clear distinction between the park and the agricultural zone. In essence, it seems as if there is a larger percentage of guava trees bordering the park than there are in the interior of the park. Directly outside of the agricultural zone is a large percentage of guava while farther away from the agricultural zone and deeper into the park area there is a lesser percentage of guava. The reasoning behind this is quite obvious- there is less human interaction in the park, and as a result, less invasive species. On the border of the park near the agricultural zone, there is a larger percentage of guava plants, likely due to the roads and the high rate of human activity in these areas. See Graphic_F for visual representation.
There is also a significant correlation between guava distribution in the park and excessive land use in the farms bordering the park. The majority of farms bordering the park are comprised of more than 50% pasture. Some farms are even 80% and 90% pasture. Furthermore, these bordering farms have a significant amount of cattle grazing, which drastically alters the land as well. As a result of these land use characteristics, there is not a high percentage of guava in these farms. The percentages of guava in these farms actually are very similar to the percentages of guava in the park. This may signify that the areas in the park are also heavily trafficked, possibly for tourist reasons, etc.
Overall, there are obvious correlations between land use and agricultural practices in the Galapogos. It is readily apparent that farms heavily used by farmers have low percentages of invasive plant species such as guava, likely because these invasive species are detrimental to farming practices. However, land parcels that were previously cleared for farming practices but are abandoned have high percentages of guava. This is likely due to the fact that these areas are not heavily used by humans because they are private property (although the owners do not use them either- in other words, they are untouched). It is also notable that areas directly adjacent to roads or buildings have very little guava trees, mainly because the ability of heavy machinery to move throughout these areas is increased.
It also seems as if areas in the park zone have a fairly low percentage of guava. This is likely due to the fact that there is not as much agriculture in these areas (cattle and various other farm animals do not bring seeds to the areas, etc.). Furthermore, there are likely conservation efforts in the park area to try and relieve these regions of invasive plant species such as guava trees. Areas that are largely untouched in the park zone also have high amounts of guava trees. For example, the entire northern corridor of our study area has a very high concentration of guava trees. This is likely due to the fact that humans do not go into the region and utilize the land (therefore they do not clear it out).
Additional data that would prove very useful in further study would be a landcover classification showing areas that have experienced some sort of invasive species removal by the local/federal government or non-profit organizations. This way, we could more easily understand correlations between land-use patterns and the existence of invasive species throughout the region.