| dc.contributor.advisor | Homeier, Jürgen Dr. | de |
| dc.contributor.author | Salazar, Laura | de |
| dc.date.accessioned | 2013-03-14T10:05:28Z | de |
| dc.date.available | 2013-03-14T10:05:28Z | de |
| dc.date.issued | 2013-03-14 | de |
| dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-000E-D223-B | de |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-3772 | |
| dc.description.abstract | Este trabajo está enfocado en la relación entre la productividad y la riqueza de especies de helechos terrestres, y en la disponibilidad de nutrientes a través de un gradiente altitudinal en Ecuador. El trabajo de campo fue realizado durante tres años entre 2009 y 2011, el cual fue llevado a cabo en 8 niveles altitudinales entre 500m y 4000m en la Cordillera Oriental de los Andes ecuatorianos. Diversidad, biomasa, productividad y caracteres funcionales de las hojas de los helechos terrestres fueron estudiados en tres cuadrantes permanentes de 400m2 por cada elevación.
Se reportaron un total de 91 especies de helechos terrestres en 32 géneros y 18 familias. A través del gradiente altitudinal, el pico más alto de riqueza de especies se registró en elevaciones medias y la riqueza de especies estuvo débilmente relacionada a medidas de productividad del ecosistema y más fuerte relacionado a la productividad de los hehechos terrestres, lo cual podría estar determinado por un incremento en el número de individuos de helechos y por la disponibilidad de nichos. Sin embargo, en cada nivel altitudinal la relación entre la riqueza de especies de helechos y la productividad de helechos fue negativa, lo cual principalmente se debe a la competencia interespecífica; es decir, en ambas escalas espaciales de este estudio, la diversidad de helechos parece estar limitada por el número de nichos disponibles y la competencia para ocupar estos nichos.
Al comparar los caracteres funcionales de las hojas de helechos y árboles a través del gradiente altitudinal se observó similaridades entre ellos. Sin embargo, se encontró una diferencia en el área específica de las hojas entre helechos y árboles, lo cual refleja los diferentes niveles de luz de ambas formas de vida. Respecto los cambios altitudinales en biomasa y productividad de helechos y árboles se encontró una notable diferencia entre estas dos formas de vida, lo cual apoya la hipótesis de que ambos grupos de plantas están creciendo limitados por diferentes factores. | de |
| dc.language.iso | eng | de |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/3.0/ | |
| dc.subject.ddc | 570 | de |
| dc.title | Unraveling the causal links between ecosystem productivity measures and species richness using terrestrial ferns in Ecuador | de |
| dc.type | doctoralThesis | de |
| dc.contributor.referee | Leuschner, Christoph Prof. Dr. | de |
| dc.date.examination | 2012-11-01 | de |
| dc.description.abstracteng | This work focuses on the relationship between terrestrial fern species richness and productivity, and on the fern nutrient availability along a tropical elevational gradient in Ecuador. During three yearly field phases between 2009 and 2011, field work was carried out at eight elevations (500 m to 4000 m) on the eastern Andean slope in Ecuador. Diversity, biomass, productivity and leaf functional traits of terrestrial ferns were recorded in three permanent plots of 400m2 each per elevation. In Chapter 1, I outlined the general purpose of this dissertation, as well as general concepts. In Chapter 2, an alternative to measure air humidity is proposed. In Chapter 3, a total of 91 terrestrial fern species, in 32 genera and 18 families are reported. Hump-shaped patterns along the elevational gradient with a peak at mid elevations adequately described fern species richness, which confirmed that fern diversity is primarily driven by energy-related variables, and that especially low annual variability of these factors favors species rich fern communities. The main results of Chapter 4 showed that along the elevational gradient, terrestrial fern species richness was only weakly related to measures of ecosystem productivity, and more closely to the productivity of the terrestrial fern assemblages as such, which appeared to be determined by an increase in the number of fern individuals and by niche availability. In addition, within elevational belts, a negative relationship between fern species richness and fern productivity was found, which was mainly due to interspecific. In other words, within both spatial scales of this study, fern diversity appears to be limited by the number of available niches by competition to occupy these niches. In Chapter 5, leaf properties, biomass and productivity of terrestrial ferns and trees along our elevational transect were studied. Ferns and trees showed similar elevation gradients for the foliar functional traits; however, a systematic difference in specific leaf area (SLA) between fern and tree leaves was found along the elevational gradient, which reflected the different light regimes of both life forms. In addition, a striking difference between ferns and trees with respect to the patterns of altitudinal change in biomass and productivity was found, which supported the hypothesis that both plant groups are growth-limited by different factors. While biomass and productivity of trees decreased with elevation, which suggests that factors (soil and air humidity, light availability) other than nutrient availability should play a key role for terrestrial ferns. | de |
| dc.contributor.coReferee | Kessler, Michael Prof. Dr. | de |
| dc.subject.ger | altitud, Ecuador, diversidad, productividad del ecosistema, productividad de helechos, disponibilidad de nutrientes | de |
| dc.subject.eng | altitude, Ecuador, diversity, ecosystem productivity, fern productivity, fern nutrient availability | de |
| dc.identifier.urn | urn:nbn:de:gbv:7-11858/00-1735-0000-000E-D223-B-1 | de |
| dc.affiliation.institute | Biologische Fakultät für Biologie und Psychologie | de |
| dc.subject.gokfull | Biologie (PPN619462639) | de |
| dc.identifier.ppn | 738437867 | de |