Author(s): Carreira, Emanuel ; Serrano, João ; Pinto Gomes, Carlos ; Shahidian, Shakib ; Paniagua, Luis L. ; Pilirito, Alexandre ; Lopes de Castro, J. ; Carvalho, Mário ; Pereira, Alfredo
Date: 2022
Persistent ID: http://hdl.handle.net/10174/32683
Origin: Repositório Científico da Universidade de Évora
Subject(s): sheep; deferred grazing; continuous grazing; botanical composition; liming; dryland pasture; Montado
The Montado is a complex agroforestry–pastoral ecosystem due to the interactions be‐ tween soil–pasture–trees–animals and climate. The typical Montado soil has an acidic pH and man‐ ganese toxicity, which affect the pastureʹs productivity and pasture floristic composition (PFC). The PFC, on the other hand, can also be influenced by the type and intensity of grazing, which can lead to significant decreases in the amount of biomass produced and the biodiversity of species in the pasture. The objective of this study was to evaluate the effect of grazing type, by sheep, and different stocking rates on the PFC throughout the vegetative pasture cycle in areas with and without dolo‐ mitic limestone application. Thus, four treatments (P1UC to P4TC) were constituted: P1UC—with‐ out limestone application (U) and continuous grazing (CG); P2UD—U and deferred grazing (DG); P3TD—with the application of limestone (T) and DG; P4TC—T and CG. In DG plots, the placement and removal of the animals were carried out as a function of the average height of the pasture (placement—10 cm; removal—3 to 5 cm). The PFC was characterized in winter, at the peak of spring and in late spring. The PFC data were subjected to a multilevel pattern analysis (ISA). The combi‐ nation of rainfall and temperature influenced the pasture growth rates and consequently the height of the pasture at different times of the year. Therefore, with the different growth rates of the pasture throughout the year, the sheep remain for different periods of time in the deferred grazing treat‐ ments. In the four treatments, 103 plant species were identified. The most representative botanical families in the four treatments were Asteraceae, Fabaceae and Poaceae. ISA identified 14 bioindicator species: eight for the winter period, three for the late spring vegetative period and three for the TC treatment.
