Patti McGill Peterson Center for International and Intercultural Studies
Fungi are essential organisms in tropical and temperate forests. Most trees have mutualistic associations with mycorrhizal fungi, decomposer fungi recycle nutrients in all ecosystems and parasites are the leading cause of disease in plants. The fruiting structures of mycorrhizal, decomposer and parasitic fungi are found in both temperate and tropical ecosystems. Very little is known about the difference between temperate and tropical forests in regards to the abundance of the fruiting structures of these three ecological types of fungi. In Costa Rica, I went to several parks in order to collect information on the types of fungi growing in the tropical ecosystems. The two different forest ecosystems, tropical and temperate, provide a set of niches for the fungi and thus a difference may be found in the abundance of the fruiting structures: shelf fungi, sac fungi, and gill fungi. These different types of fungi provide different reproductive strategies that may explain their existence and abundance in different ecosystems.
While in Costa Rica, I visited several national parks and reserves including Monteverde Reserve and Santa Elena Reserve, Tapanti National Park, Cahuita National Park and the Manuel Brenes Reserve. I also visited the Poas Volcano and Irazu Volcano, but did not find any fungi growing near the trails. The Monteverde and Santa Elena Reserves are both located in a collective region called Monteverde, so though some fungi were discovered at each reserve I considered them all part of the Monteverde region. The map shown on this page refers to where each park or reserve is in Costa Rica. Monteverde is a cloud forest, Tapanti is in the Valle de Orosi (Orosi Valley) well known as an agricultural area in the continental divide mountain range, Cahuita is located on the Southern Caribbean coastline as a part of the humid tropical rainforest and the Manuel Brenes Biological Reserve is also a humid tropical rainforest located in the Tilaran mountain range that connects with the Juan Castro Blanco National Park.
At each reserve I walked the trails looking for fungi living alongside the trails, as it is not permitted for guests to wander off trail (mostly because of deadly poisonous snakes). I took pictures and notes of the fungi I found. I had originally planned on taking specimens back to the Universidad de Costa Rica to examine more closely for identification, but quickly discovered that was illegal. Instead, I began to use the notes once I was back in the United States to identify the fungi. I needed more training regarding the specific species to identify them, thus alongside my Mycology course and SYE I began to identify the genera of the fungi and some of the species. I grouped the fungi by types previously mentioned, sac, shelf and gill and made a graph showing the distribution overall in the Costa Rican forests as well as a couple of tables outlining the information I have completed analyzing. Because I was not able to go off trail, the information is not conclusive to what types of fungi are evident in all of the Costa Rican parks I went to, only those growing along the trails. However, it is noted that there were more specimens found in the Cahuita and Monteverde parks. This may be due to moisture, as Cahuita is situated on the Caribbean coastline where there is high precipitation and Monteverde Reserve is a cloud forest.
I continue to analyze the fungi I discovered in the various parks and have not presented all of the information gathered here.