1. Context
Terra das Freiras (TF) and Grupo São Mateus (GSM) are located in Natura 2000 site Monfurado (SCI). Both farms are integrated in a “ZIF” (forest intervention zone), benefiting from a forest management plan. Grupo São Mateus is exploited under organic certification. Both farms are composed by a tree layer of cork oaks (Q. suber). They are exploited for cork production and livestock (suckler cows in TF / suckler cows and ships in GSM). GSM is also exploited for forage production. A rotational grazing system across all the parcels is established in both farms.
Installation of a biodiverse pasture (from Fertiprado) was made in 2012 in both farms. In the last two years, phosphorous has been added to improve soil fertility (in different parcels). Supplementary food is not needed. Apart from grazing, production of hay in GSM provides food for the livestock. Only eventually, import of food is necessary. Water availability in the farms is sufficient for supplying livestock.
Both farms show different regeneration status and composition of scrub layer, so the actions to be implemented will also differ from one another. There are no symptoms of Seca in the farms.
UEvora and the farmer propose to create 4 scrubs islands with high scrub density per farm, preferably without cork oaks inside as the farms are exploited for cork production (by 2026 the cork is expected to be collected in a process that requires removing of scrubs). The main objective of the C actions is to improve the scrub layer by protecting islands from livestock grazing preferably in areas with rockery structures to favour biodiversity of fauna. Plantation of additional scrub species in the poorer islands is foreseen, after evaluation in spring 2023. The enrichment of the scrub islands will be performed in the first instance with seedballs prepared with seeds collected locally (summer 2022) and after, with plantation of species multiplied by Ecohabitat from seeds provided by UEvora (from Sitio de Monfurado). If necessary, additional measures can be applied later such as cleaning of any exotic species present in the islands. The objective is to improve and diversify the scrub layer within the islands. Thus, preparatory actions to generate the seedballs need to be performed as soon as possible, including the collection of seeds from the farms.
Carla and Anabela from UEvora, have made a preliminary census of bushes in the islands, that will be completed once the protective meshes for delimitation of the islands are installed.
The soils at TF and GSM sites are described as Cambisol and Luvisol types (IUSS, 2015) respectively. Both presents Mn toxicity as a natural property of these acidic and poorly drained soil types evolved from the most ancient Granite, Schist and gneiss bedrocks of Iberic Peninsula. The Mn toxicity is corrected with the application of dolomite calcite (Goss and Carvalho, 1992) and its application and validation at the study sites is foreseen for September 2022 onwards.
The description of the specific measures defined for the farms are as follows.
2. Actions
2.1 Terra das Freiras
This farm of 205 ha is composed mainly of cork oaks, with high density/low biodiversity scrub layer, dominated by Crataegus monogyna and Cistus salviifolius. The farm is characterized by high regeneration of the Quercus suber layer. Protection of natural regeneration of Quercus is done using wire net protectors. There is no mobilization of soils (no tillage) and the shrub control is performed with shredders (every 8 years).
The measures defined during the visit are the following ones:
2.1.1. Protection of shrubs
Four scrub islands will be installed at the four sites finally selected. For the construction of the four islands, four 12 m x 12 m metal enclosures will be installed, supported by corrugated steel; an access to the interior of the islands will be provided on one of the sides. Next to the island enclosure but outside, a point shall be selected for control soil sampling; this point shall be protected with a small exclusion cage to avoid interaction with livestock.
If possible, the islands should cover areas of different irradiance to test the effect of light on actions. Eventually, grass patches may be sown inside the islands if they are of interest.
Island 1: area with a rockery structure and some cork oaks inside.
Island 3: area with a rockery structure and some cork oaks inside. Covering the rocks, there is a species of lichen under protection.
Island 4: area without rockery structure. No cork oaks inside. One individual of Q. ilex. High biodiversity of shrubs: G. Scorpius, C. salviifolius, zarzamora, helechos.
Island 5: area with a rockery structure. One individual of Q. ilex and Pyrus sp. One exclusion cage.
2.1.2. Protection of Quercus
Mechanised clearing will be carried out on an area of about 13 hectares, it is an area with a lot of monospecific scrub, mainly Cistus spp. The 4 islands of scrubland are included within this area, but protected by the enclosure. Exclusion cages for the protection of Quercus spp regeneration will be installed, inside the cleared area, at the rate of 10 pcs/ha.
2.1.3. Naturalization of a livestock pond
Water sources in this farm are one pond, one well, one fountain and one stream. The pond is completely devoid of vegetation in its margins. The quality of water is poor. The pond will be fenced in its surroundings to avoid livestock access. A water trough will be placed downstream of the pond to supply the livestock; a reservoir will also be installed which will be filled from the pond by gravity (difference in elevation) and will feed the water trough. A mesh will be installed in the middle to divide the pond in case the livestock needs water. Access for pigs will be installed.
2.1.4. Actions for improvement of fauna
– Insect shelters inside islands or in the surrounding area.
– Nest boxes for common kestrels (Falco tinnunculus) outside the islands.
– Nest boxes for bats outside the islands. In trees (> 3 m), possibility of locating them in the surrounding area of the pond.
– There are not rabbits, so no measures will be taken.
– Actions for amphibians and reptiles not defined yet.
2.1.5. Maps
2.1 Sao Mateus
This farm of 297 ha is composed mainly of cork oaks, with low density/biodiversity scrub layer, dominated by Crataegus monogyna. Other bushes present in the farm are: Ruscus aculeatus, Smilax aspera y Asparragus sp and Genista Scorpius. The farm is characterized by low regeneration of the Quercus suber layer. Protection of natural regeneration of Quercus (very sparce in GSM) is done using wire net protectors. There is no mobilization of soils (no tillage) and the shrub control is performed with shredders (only in the top of hills). The measures defined during the visit are the following ones:
2.2.1. Protection of shrubs
For the construction of the four islands, four 12 m x 12 m metal enclosures will be installed, supported by corrugated steel; an access to the interior of the islands will be provided on one of the sides. Next to the island enclosure but outside, a point shall be selected for control soil sampling; this point shall be protected with a small exclusion cage to avoid interaction with livestock. If possible, the islands should cover areas of different irradiance to test the effect of light on actions. Eventually, grass patches may be sown inside the islands if they are of interest.
2.2.2. Regeneration of Quercus
Plantation of cork oaks near “nurse scrubs” already present in the farm outside the islands. The seed will be collected from the farm the coming autumn.
2.2.3. Actions for improvement of fauna
– Insect shelters inside islands or in the surrounding area
– Nest boxes for birds outside the islands; the owner has specified that he does not want nest boxes for Passeriformes, as there are no populations of them on the farm. The possibility of installing facilities for other bird species will be considered.
– Nest boxes for bats outside the islands. There are two poles in the farm near de islands and a drinking trough, where two boxes per pole will be installed (3-4 meters high and less than 300 m from water).
– There are not rabbits, so no measures will be taken.
– Actions for amphibians and reptiles not defined yet.
2.2.4. Maps
