Herbivory effects of Formosan sika deer (Cervus nippon taiouanus) on community composition of native woody seedlings in a tropical forest
| Autor: | Jun-Wei Lu, 呂俊緯 |
|---|---|
| Rok vydání: | 2018 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 106 Deer play a key role in a variety of ecosystems, and they have long-term impacts on plant populations and communities. However, most of previous studies used species-based approaches and indicated that impacts of deer herbivory on forest ecosystems are context-dependent and inconsistent among ecosystems. The studies with species-based approaches may overlook strong relationship between feeding preference of deer and functional traits of plants. In this study, we would like to evaluate effects of Formosan sika deer (Cervus nippon taiouanus) herbivory on community assembly of woody seedlings in a Taiwanese tropical forest. Two questions were addressed in this study. First, would deer show preferences on woody seedlings? Second, would deer herbivory cause directional changes in functional composition of woody seedlings? In December 2014, we established 15 deer exclosure and control plots adjacent to the Kenting Forest Dynamics Plot. We tagged and mapped every seedling of woody plant taller than10 cm at a three-month interval from January, 2015 to October, 2017. Four functional traits, including leaf thickness, specific leaf area (SLA), leaf dry matter content (LDMC), and photosynthetic capacity, were used to estimate functional diversity. Our results showed that there were 2333 seedlings of 35 woody species in exclosure plots and 888 seedlings of 22 woody species in control plots. Species diversity of woody seedlings in the exclosure plots were significantly higher than control plots. Moreover, the pattern of seedling recruitment and survival were species-specific. The community-weighted mean of leaf thickness in exclosure plots was significantly lower than control plots. The opposite pattern occurred in the community-weighted mean of specific leaf area. Furthermore, functional diversity of woody seedlings was not significantly different between the exclosure and control plots. In conclusion, deer herbivory led to decreased species diversity, but did not alter functional diversity significantly. This study suggested that appropriate protection of palatable species was necessary for the conservation of species diversity in the Nature Reserve. Our study can be applied to develop management plans for the Kenting Uplifted Coral Reef Nature Reserve. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|