Competing conceptions of a “Swiss” national identity and their effect on attitudes towards the “foreign other”

Treball Final del Màster Universitari en Estudis Internacionals de Pau, Conflictes i Desenvolupament (Pla de 2013). Codi: SBG119. Curs acadèmic 2014-201

The effects of Eisenia fetida (Lumbricidae) and vermicomposting on earthworm populations in Monteverde, Costa Rica

Eisenia fetida (Lumbricidae) is an African earthworm species used in vermicomposting in the larger Monteverde region of Costa Rica. Despite its widespread use and growing popularity, little is known about the impact that introducing E. fetida has on local earthworm species. Exotic earthworms have the potential to drastically change the soil composition and community structure causing cascading effects throughout the ecosystem. However, previous studies have found signs of possible niche partitioning and that species richness and abundance actually increased in the presence of E. fetida. Taking samples for six farms using vermicomposting and six without, I found that vermicomposting actually increased the species richness of earthworm communities when considering all samples collectively (H’= 1.09, 0.78, t = 2.30, df = 267, P \u3c 0.05 ), when only considering non-coffee farms (H’ = 0.78, 0.39, t = 2.13, df = 60, P \u3c 0.05), and when comparing non-coffee farms to coffee-farms (H’ = 1.05, 0.70, t = 2.28, df = 114, P \u3c 0.05). However, when looking at other subsets only including farms having applied vermicompost within the last year, excluding farms using greenhouses, and only considering coffee plantations there was no significant difference in earthworm communities. Based on this study, it seems that although E. fetida is entering farm soils, there is no negative impact on preexisting earthworm populations. Eisenia fetida (Lumbricidae) es una especie de lombriz africana que es usada para compostaje vermicular en la región de Monteverde, Costa Rica. A pesar de su uso común y de la popularidad del abono, poco se sabe sobre el impacto que E. fetida tiene en las lombrices locales. Las lombrices exóticas pueden cambiar la composición del suelo y la estructura de la comunidad drásticamente, causando efectos sobre todo el ecosistema. Sin embargo, estudios previos han indicado la posibilidad de que compartan nichos y que la riqueza de especies y la abundancia aumenta cuando E. fetida esta presente.https://digitalcommons.usf.edu/tropical_ecology/1008/thumbnail.jp

The effects of Eisenia fetida (Lumbricidae) and vermicomposting on earthworm populations in Monteverde, Costa Rica

Eisenia fetida (Lumbricidae) is an African earthworm species used in vermicomposting in the larger Monteverde region of Costa Rica. Despite its widespread use and growing popularity, little is known about the impact that introducing E. fetida has on local earthworm species. Exotic earthworms have the potential to drastically change the soil composition and community structure causing cascading effects throughout the ecosystem. However, previous studies have found signs of possible niche partitioning and that species richness and abundance actually increased in the presence of E. fetida. Taking samples for six farms using vermicomposting and six without, I found that vermicomposting actually increased the species richness of earthworm communities when considering all samples collectively (H’= 1.09, 0.78, t = 2.30, df = 267, P \u3c 0.05 ), when only considering non-coffee farms (H’ = 0.78, 0.39, t = 2.13, df = 60, P \u3c 0.05), and when comparing non-coffee farms to coffee-farms (H’ = 1.05, 0.70, t = 2.28, df = 114, P \u3c 0.05). However, when looking at other subsets only including farms having applied vermicompost within the last year, excluding farms using greenhouses, and only considering coffee plantations there was no significant difference in earthworm communities. Based on this study, it seems that although E. fetida is entering farm soils, there is no negative impact on preexisting earthworm populations. Eisenia fetida (Lumbricidae) es una especie de lombriz africana que es usada para compostaje vermicular en la región de Monteverde, Costa Rica. A pesar de su uso común y de la popularidad del abono, poco se sabe sobre el impacto que E. fetida tiene en las lombrices locales. Las lombrices exóticas pueden cambiar la composición del suelo y la estructura de la comunidad drásticamente, causando efectos sobre todo el ecosistema. Sin embargo, estudios previos han indicado la posibilidad de que compartan nichos y que la riqueza de especies y la abundancia aumenta cuando E. fetida esta presente.https://digitalcommons.usf.edu/tropical_ecology/1008/thumbnail.jp