Utilização e impacto dos cervídeos na vegetação lenhosa

• Author(s): Cortez, José Paulo Mendes Guerra Marques
• Date: 2010
• Persistent ID: http://hdl.handle.net/10400.5/3869
• Origin: Repositório da UTL
• Subject(s): ungulates; roe deer; red deer; diet composition; browsing; tree rubbing; holm oak
• Document Type: Doctoral Thesis
• Language: Portuguese
• Advisor(s): Rego, Francisco Castro

Description

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia Roe deer (Capreolus capreolus L.) and Red deer (Cervus elaphus L.) coexist in Northeastern Portugal. This work aims to increase the knowledge on the effects of these two species on Mediterranean lignified plants, in particular on shrub like vegetation. To understand these effects we studied the diet of both deer species during two consecutive years. Red deer eat more grasses during Spring, contrasting with Summer, when 80% of the diet was shrubs and broadleaved trees. Roe deer consumed more shrubs and trees, throughout the year and had a more diversified diet than Red deer. Other important effect of deer is by tree rubbing, which occurs mainly during the rut season. Red deer marked trees preferably along edges of forest plantations whereas Roe Deer showed a preference for inner and smaller trees inside forest plantations. We used simulated browsing to understand how Holm oak responds to deer attacks, as well as two mediterranean shrub species Gum cistus (Cistus ladanifer) and Pterospartum tridentatum. P. tridentatum responsed with an increase of biomass and in the root system diameter. Holm oak responded with an increase at crown level and Gum cistus reduced biomass when browsed treatment was applied. Seed regeneration was also studied on Holm oak, using deer exclosures. Seedling survival was higher inside exclosures after 3 years.