1. Context
The Terra das
Freiras (TF) estate and the São Mateus Group (GSM) are located in Monfurado
(ZEC), which belongs to the Natura 2000 network. Both farms are part of a “ZIF”
(Forest Intervention Zone), benefiting from a forest management plan. The GSM
is managed under organic certification. Both farms are composed of a cork oak (Quercus
suber) tree layer. They are exploited for cork production and livestock
farming (suckler cows at TF / suckler cows and sheep at GSM). GSM is also
exploited for fodder production. On both farms, a rotational grazing system is
established on all plots.
A biodiverse pasture
was installed in 2012 on both farms. In recent years, phosphorus has been added
to improve soil fertility (in different plots). Supplementary feeding is not
necessary. In addition to grazing, hay production on the GSM provides feed for
the livestock. Feed imports are only necessary in some cases. The availability
of water on the farms is sufficient to supply the livestock.
The two farms have
different states of regeneration and composition of the shrub layer, so the
actions implemented were also different from each other. There are no symptoms
of drought on these farms.
The University of
Évora (UÉvora) and the owner proposed the creation of four islands of scrub
with a high density of shrubs per farm, preferably without cork oaks in the
interior, as the properties are exploited for cork production (in 2026, cork is
expected to be harvested in a process that requires the removal of scrub). The
main objective of actions C is to improve the shrub layer, protecting the
islands from livestock grazing, preferably in areas with rocky structures to
promote biodiversity. The planting of additional shrub species on the poorest
islands was planned, following the results obtained in the assessment of their
condition during the spring of 2023. The enrichment of the islands with shrubs
was initially carried out by planting species propagated by EcoHabitat from
seeds provided by UÉvora (from the Monfurado Site) and, subsequently, by
placing seed balls prepared from locally harvested seeds. The aim is to improve
and diversify the shrub layer within the islands.
The soils of the TF
and GSM estates are described as Cambisol and Luvisol types (IUSS, 2015),
respectively. Both have manganese (Mn) toxicity, a natural property of these
types of acidic and poorly drained soils, developed from the oldest granite,
schist and gneiss beds of the Iberian Peninsula. With the aim of increasing
soil fertility and, consequently, pasture diversity and quality, Mn toxicity was
corrected by adding dolomitic limestone (Goss and Carvalho, 1992) and its
application and validation at the study sites was carried out in autumn/winter
2022.
The specific
measures defined for the pilot farms are described below.
2. Actions
2.1 Terra das Freiras
This 205 ha property consists mainly of cork oaks, with a high-density shrub layer, but low biodiversity, dominated by Calicotome villosa and Cistus salviifolius. The property is characterised by high regeneration of the tree layer, Quercus suber. The natural regeneration of Q. suber is often protected by metal mesh. There is no soil mobilisation (no ploughing) and scrub control is carried out with shredders (every 8 years).
2.1.1. Shrub islands
Four islands of vegetation were selected that already had some diversity of shrubs in the area of operation, as well as the presence of rocky outcrops. The islands were fenced off using metal mesh, each measuring 16 m x 12 m, and one side was left accessible to the interior for monitoring. All have a designated area of active regeneration and another area of passive regeneration. The first is where we planted and placed seed balls; the second will be for comparison and verification of how the system reacts when we only exclude grazing.
Native shrubs were planted in January 2024, adding species with different functions in the ecosystem, such as honey production, berry production, disease control, and wildlife refuge. Among the selected species, Cistus populifolius, Crataegus monogyna, Myrtus communis and Salvia rosmarinus stand out. In addition, seed balls of three different species were installed in the active regeneration area: Rosa sp., Rubia peregrina and Tamus communis. This is an additional technique we are testing to enhance shrub diversity and thus contribute to local biodiversity.
Preliminary data from the plantations (monitoring carried out in October 2024) show an average survival rate of around 30%. Some species had survival rates close to zero, as they were more sensitive to unfavourable summer conditions (e.g. Pistacia lentiscus, Smilax aspera and Ruscus aculeatus), and these were the species selected for reinforcement in the plantings that took place in January 2025. Further monitoring will be carried out during the coming autumn season.
2.1.2. Soil correction and grazing monitoring
In an area of 13 ha dominated by a poorly diverse shrub community (as mentioned above), a trial of shrub clearing and dolomitic limestone correction was proposed, with the aim of improving soil quality and, consequently, herbaceous pasture. The actions were implemented in the winter of 2023. To assess the effects of these practices, soil, pasture and cattle movement samples were taken in this area and compared with another control area (where the measures were not implemented). We will carry out the final monitoring in the coming months and compare the results to see whether these actions do indeed have positive consequences on any of these components of the Montado.
2.1.3. Protection of natural regeneration
Terra das Freiras has a huge amount of natural cork oak regeneration in the area selected for the project intervention. To safeguard its maintenance in the future, we decided to mark and protect most of the young trees before clearing and correcting with dolomitic limestone, in an area of 13 ha. Grazing exclusion cages were installed, using sun mesh, with a protection rate of around 10 individuals/hectare. This area can therefore be used for cattle grazing without jeopardising the future viability of the Montado.
2.1.4. Renaturalisation of the pond
The estate’s water sources are a pond, a well, a spring and a temporary stream. The pond was completely devoid of vegetation on its banks and the water quality was poor due to the presence of cows that frequent the area. It was proposed to fence it off to prevent cattle from accessing it. Downstream from the pond, a drinking trough was installed that fills with water by gravity (difference in elevation), thus serving as a watering place for the animals. The pond was also divided in half by a fence, in case the cattle needed to drink water directly from it. To enhance biodiversity, ash trees, reeds and rose bushes were planted on the banks of the pond, and a floating raft with aquatic plants was placed there.
2.1.5. Actions to promote wildlife
Inside each island of shrubs and in the renaturalised pond enclosure, hotels for pollinating insects were built. In the TF action area, nesting boxes for passerines (titmice and nuthatches) and shelter boxes for bats were also installed. To provide refuge for amphibians and reptiles, shelters were built with stones and logs on the banks of the pond. These measures aim to promote biodiversity and maintain ecosystem functions such as pollination and pest control.
2.1.5. Maps
2.2 Sao Mateus
This 297-hectare property consists mainly of cork oaks, with a sparse shrub layer dominated by Crataegus monogyna, Calicotome villosa and Rubus ulmifolius. Other shrubs present on the estate include Ruscus aculeatus, Smilax aspera and Asparagus spp. This property is characterised by low natural regeneration of Quercus spp. Regeneration is protected by protective nets. There is no soil mobilisation (no ploughing) and weed control is carried out with shredders (only on the upper part of the slopes).
2.2.1. Shrub islands
As in TF, four islands of vegetation that already had some diversity of shrubs were selected in the plot where the actions were implemented. The islands were fenced off using metal mesh, each measuring 16 m x 12 m, and one side was left accessible for monitoring. All have a designated area of active regeneration and another area of passive regeneration. The first is where we carried out the planting and placed the seed balls; the second will be for comparison and verification of how the system reacts when we only exclude grazing.
The native shrubs were planted in January 2024, adding species with different functions in the ecosystem, such as honey production, berry production, disease control and refuge for wildlife. Among the selected species, Cistus crispus, Lavandula pedunculata, Arbutus unedo and Pyrus bourgeana stand out. In addition, seed balls with the same three species used in TF: Rosa sp., Rubia peregrina and Tamus communis, were installed in the active regeneration area as a complementary technique to promote local biodiversity.
Preliminary data from the plantations (monitoring carried out in October 2024) show an average survival rate of around 48%. There were not as many losses as in TF, due to the unfavourable summer conditions. Nevertheless, plant replacement actions were carried out in January 2025. Further monitoring will be carried out during the coming autumn season.
2.2.2. Promotion of tree regeneration
As in TF, four islands of vegetation that already had some diversity of shrubs were selected in the plot where the actions were implemented. The islands were fenced off using metal mesh, each measuring 16 m x 12 m, and one side was left accessible for monitoring. All have a designated area of active regeneration and another area of passive regeneration. The first is where we carried out the planting and placed the seed balls; the second will be for comparison and verification of how the system reacts when we only exclude grazing.
The native shrubs were planted in January 2024, adding species with different functions in the ecosystem, such as honey production, berry production, disease control and refuge for wildlife. Among the selected species, Cistus crispus, Lavandula pedunculata, Arbutus unedo and Pyrus bourgeana stand out. In addition, seed balls with the same three species used in TF: Rosa sp., Rubia peregrina and Tamus communis, were installed in the active regeneration area as a complementary technique to promote local biodiversity.
Preliminary data from the plantations (monitoring carried out in October 2024) show an average survival rate of around 48%. There were not as many losses as in TF, due to the unfavourable summer conditions. Nevertheless, plant replacement actions were carried out in January 2025. Further monitoring will be carried out during the coming autumn season.
2.2.3. Actions to promote wildlife
As was done in TF, hotels for pollinating insects were also built on this estate and placed inside each island of shrubs. In the GSM area, nesting boxes for passerines (titmice and nuthatches) and bat shelters were also installed. These measures aim to promote biodiversity and maintain ecosystem functions such as pollination and pest control.
2.2.4. Maps
