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- The transformation of the silvopastoral landscape of Montesinho Natural Park (1995 – 2021)Publication . Seripieri, Vitor Henrique Mistro; Castro, José; Silva, Maria Madalena; Castro, Marina; Seripieri, Vitor Henrique MistroIn the grazing areas of the Montesinho Natural Park (PNM), the diet of small ruminants is shaped by the available landscape, through the daily routes chosen by the shepherd to feed his flock. Thus, in addition to grazing, sheep and goats benefit from a combination of agricultural by-products and spontaneous vegetation, such as stubble fields, chestnut and olive groves, leftovers and pruning, as well as forests and scrubland. Changes in land use inevitably lead to adaptations in pastoral routes. An analysis of the evolution of the landscape explains the changes in the various land uses that make up the landscape, whether natural, semi-natural or anthropic, and which have been determined by global changes, in particular climate change. This study updated PNM's Natural and Semi-Natural Vegetation Map (1995), an analogue cartography of great historical value that was transferred to digital format, requiring a refinement of its geometry and classification to ensure that the results were not affected by the different methodologies inherent in its creation. To achieve this, we chose to adapt the polygons of the original cartography to the currently available land structure geometry, namely the ISIP geographical database, and to update it based on images from 2021, complemented by field visits and visual interpretation of other images from different seasons and dates. The data were processed in a GIS environment, using the QGIS tool, which allowed the interpretation of the landscape transformation in the last 26 years, quantified by a transition matrix, and the trend for the next 26 years. From the results we can conclude that there has been a drastic decrease in the areas of extensive and intensive dry farming (-47%), while an increase perennial plantation (olive and chestnut groves) (+38%) has been observed, with some peculiarities. The other categories remained constant and are expected to continue to increase, albeit at a slower rate.
- Relembrar em comum: memórias e vivências do sistema agro-silvo-pastoril em MontesinhoPublication . Amieira, João; Seripieri, Vitor Henrique Mistro; Castro, José; Frazão-Moreira, Amélia; Castro, Marina; Seripieri, Vitor Henrique MistroInstituídas como Parque Natural, as serras de Coroa e Montesinho (nordeste de Portugal) são palco de grandes transformações sociais, económicas, políticas e ecológicas. Materializadas a diferentes escalas, temporais e espaciais, estes processos de mudança permanecem ainda hoje como memória, individual e coletiva. No seu contexto agro-silvo-pastoril, pastores e comunidades são a chave para a compreensão de como tais dinâmicas transformadoras se manifestam nos ecossistemas e nas (re)negociações das práticas e dos significados do presente, foco do projeto de investigação multidisciplinar PASTOpraxis (FCT MTS/CAC/0028/2020) em que este estudo se insere. Partindo de um conjunto de metodologias complementares, explorámos o modo como as memórias do sistema agro-silvo-pastoril são (re)significadas no presente. Com recurso a fotografias aéreas de 1968, organizaram-se encontros com as populações locais, permitindo um momento de reflexão sobre a paisagem e as memórias associadas. Conclui-se que, destes atos de relembrar em comum (re)nascem narrativas sobre o próprio tecido socioecológico das aldeias, permitindo reflexões sobre as transformações do sistema agro-silvo-pastoril, os antigos locais convívio e trabalho, as vivências de injustiças e desigualdades, e as relações multiespécie. Este (re)encontro sensorial com a paisagem e a memória torna-se, desta forma, indispensável para pensar em comum, futuros resistentes mais justos para todos.
- Impacts of extensive sheep grazing on soil physical and chemical quality in open mountain forests, NE PortugalPublication . Fonseca, Felícia; Castro, Marina; Alves, Leonardo Kipper; Castro, José; Figueiredo, Tomás deGrazing and mechanical clearing are common techniques for vegetation management in open Mediterranean forests. Despite its recognized benefits in the prevention of high-intensity and severity forest fires, it is essential to consider its impacts on the physical and chemical soil properties. In an open mountain forest located in the NE of Portugal, soil samples were analyzed at depths 0–5, 5–10, and 10–20 cm collected at two moments: before mechanical clearing, (Control) and after 18 months of extensive sheep grazing, in areas without grazing, only mechanical clearing (MC) and in areas with both mechanical clearing and grazing (MCG). The results indicate that vegetation cutting has induced a significant decrease in extractable potassium, and an increase in the soil organic matter and total nitrogen. The exchangeable bases and the exchangeable acidity did not undergo expressive changes, as indicated by the pH values and the cation exchangeable capacity. After grazing, extractable phosphorus and potassium, organic matter, total nitrogen, exchangeable bases, and cation exchangeable capacity have increased significantly in the topsoil (0–5 cm), reducing soil acidity. Regarding physical properties, only soil permeability has been negatively affected by grazing. Mediterranean mountain open forests management with the combination of vegetation clearing and extensive sheep grazing proved to be effective in reducing vegetable fuel availability and improving soil quality.
- Quantification and characterization of surface fuel material in different stands in the north-east of PortugalPublication . Souza, Júlio Henrique Germano de; Alves, Leonardo Kipper; Castro, MarinaThe aim of this study was to characterize the surface fuel material, based on its quantification and classification of hazardousness in four forest stands (Pinheiro manso, Castinçal,Sobreiral and Carvalhal) in the northeast of Portugal. The fuel material was classified according to its diameter, in dangerous (<1cm), semi-ha-zardous (>1cm) and green, moisture was assessed with drying in greenhouse. The Chestnut stand presented the largest quantity of fuel material (30.54 ton/ha; 16.40 ton/ha). Carvalhal had the lowest moisture content for summer (6.87%) and Pinheiro, the highest average value for winter (149.65%). The cork oak pre-sented the greatest risk, due to the high quantity of fuel material coupled with low humidity in the summer. f
- Impacto del pastoreo extensivo en las propiedades del suelo en bosques abiertos de montaña en la región mediterráneaPublication . Fonseca, Felícia; Alves, Leonardo Kipper; Lopes, Ana Teresa; Castro, Marina; Castro, José; Figueiredo, Tomás de
- Knowledge and grazing journeys: dialogues on adaptive responses to climate change in Montesinho (Portugal)Publication . Frazão-Moreira, Amélia; Castro, José; Castro, João Paulo; Amieira, João; Serieperi, Vitor; Castro, Marina; Aleixo-Pais, Isa G.Biophysical, ecological and sociocultural local adaptative responses of pastoralism (small ruminant indigenous breeds) to climate change. Understanding the place of local ecological knowledge and climate perceptions in adaptive responses. Engaged Researech Building on the dialogue between different types of knowledge (herders, state service technicians, zootechnical and forestry scientists, anthropologists/ethnobiologists), the results are intended to equip practitioners and decision-makers with tools that guarantee the continuity of mountain pastoralism while safeguarding local experiences and knowledge.
- Temperature Effect on Rheological Behavior of Portuguese HoneysPublication . Afonso, Maria João A.P.S.; Magalhães, Marta; Fernandes, Luana; Castro, Marina; Ramalhosa, ElsaIn the present work the temperature effect on rheological properties of Portuguese honeys was studied for the fi rst time. Two unifl oral honeys – heather and rosemary – and a polyfl ower honey were analyzed. All honeys showed fl ow independence over time and behaved as Newtonian fl uids at the studied temperature and shear rate ranges. For all honeys it was found that the viscosity decreased with temperature and the rosemary honey was the one that always presented the lowest viscosity at 30°C (6120 mPa·s), 50°C (603 mPa·s) and 70°C (145 mPa·s). The temperature dependence of viscosity was well described by the T B A K e 0 equation. Nevertheless, good regression coeffi cients were also obtained when fi tting the experimental data to the Arrhenius model, showing the rosemary honey to be less temperature sensitive. The results obtained in this study are of great interest to beekeepers and industrials that handle and prepare eatable honey-based products because they will be better informed about the best type of honey to use.
- Preservação vs. utilização do território: a nova utilidade social do pastor e o acesso às terras de pastagensPublication . Rêgo, Júlio Sá; Castro, MarinaReconhecer um território como paisagem cultural tende a outorgar à sua beleza e/ou biodiversidade um valor universal, retirando à população local sua legitimidade unilateral de decisão sobre o uso desse território. A conservação da paisagem torna-se prioritária e passa a ter precedência sobre a continuidade das atividades humanas que podem vir a ameaçá-la. Contudo, paisagens culturais são territórios historicamente construídos frutos da ativa interação entre o ambiente natural e as comunidades humanas. A alteração desse equilíbrio construído pode provocar tanto degradações ambientais como injustiças a populações que da terra tiravam o seu sustento. Inúmeros casos ilustrativos dessa relação estão disponíveis na literatura. Em Portugal, agricultura, pastorícia e queimadas foram os agentes dominantes de modelação da paisagem desde o Neolítico. No decorrer do século XX, entretanto, a expansão da área florestal nos baldios e o seu fecho a outros usos provocou uma asfixia do sistema agropastoril tradicional e induziu uma rápida modificação da ocupação e do uso da terra, especialmente em regiões onde a pastorícia era importante. Com o gado proibido de acessar as novas florestas, a pastorícia foi seriamente comprometida por falta de pastos. A fragmentação do equilíbrio territorial que prevalecia propulsionou comunidades pastoris a uma situação de precariedade e vulnerabilidade social, e deu espaço a um regime de incêndios descontrolado conhecido como Terceiro Fogo. Há, hoje, um discurso crescente que reconhece a utilidade social da pastorícia na manutenção da biodiversidade e prevenção de incêndios florestais. O discurso, no entanto, induz mudanças nas práticas e relações sociais. Após contextualizar esse processo de desarticulação do equilíbrio territorial em Portugal, este trabalho procura retratar o cotidiano de pastores – agora então cunhados de utilidade social – no acesso às terras de pastagens. Ele resulta de uma investigação de doutoramento em antropologia em curso, cujos dados são coletados através de diálogos e observação no Centro e no Norte do país. Resultados preliminares indicam que a reconciliação das antes antagônicas dinâmicas de conservação da natureza e utilização do território ainda não é efetiva. O cotidiano de pastores depara-se com múltiplos constrangimentos oriundos de uma visão conservacionista do ambiente. Da construção de infraestruturas necessárias à pastorícia ao pastoreio em zonas florestais, pastores têm de lidar com comportamentos individuais de autoridades e regulamentos de ordenamento do território restritivos que podem levar até ao abandono da atividade. O programa das “cabras sapadoras” é, nesse sentido, positivamente percebido pelo seu potencial de promover a legitimidade social da pastorícia.
- The impact of goats grazing on understory vegetation of cork oak woodlandsPublication . Souza, Júlio Henrique Germano de; Mosquera-Losada, Maria Rosa; Castro, MarinaThe aim of this study is to evaluate the effects of high grazing pressure for short, intermittent periods (1-2 h per day) on fuel load management in cork oak (Quercus suber L.) forests in the north-eastern region of Portugal. This evaluation aims to understand the effectiveness of targeted grazing as a forest management tool, specifically in reducing fuel load accumulation and thereby potentially reducing wildfire risk. In addition, this study extends its analysis to examine the time required for vegetation recovery in the absence of grazing, with the aim of determining the optimal grazing interval. Changes in herbaceous and shrub cover, herbaceous biomass and phytovolume were compared between grazed and ungrazed plots over a period of thirty-four months. Using a stocking rate of 400 goats per hectare for 21 cumulative hours over 12 days resulted in a 93.43% reduction in shrub phytovolume and a 76.2% reduction in shrub cover. Herbaceous biomass also decreased from 53.80 +/- 7.82 g m-2 to 17.76 +/- 6.29 g m-2 in the grazed areas. Twenty-two months after cessation of grazing, no significant differences in plant and shrub cover or herbaceous biomass were observed. The results highlight the effectiveness of targeted grazing in managing fuel loads in cork oak woodlands, with pronounced short-term benefits. However, the rapid recovery of vegetation in the absence of grazing highlights the need for a strategic and continuous management approach to maintain the benefits of fuel reduction.
- Caracterização dos materiais combustíveis em diferentes povoamentos florestais na região nordeste de PortugalPublication . Souza, Júlio Henrique Germano de; Alves, Leonardo Kipper; Castro, MarinaObjetivou-se com este estudo caracterizar o material combustível superficial, a partir da sua quantificação e classificação de perigosidade em duas estações do ano e em quatro povoamentos florestais (Pinhal manso, Castinçal, Sobreiral e Carvalhal) no nordeste de Portugal. O material combustível foi classificado em perigosos (<1cm) semi-perigosos (>1cm) e verdes, a umidade foi avaliada com secagem em estufa. O povoamento de Castanheiro é o que possui a maior quantidade de material combustível (30,547; 16,40 ton/ha). O pinhal apresenta o maior risco, devido a elevada quantidade de material combustível atrelada a baixa umidade no período crítico (verão).