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- Carbon sequestration in chestnut coppices: impact of shoot density simulated with the CO2Fix modelPublication . Patrício, Maria Sameiro; El Baine, Chaimae; Nunes, LuísThe carbon cycle plays a vital role in maintaining ecosystem stability by regulating the flow of organic matter and influencing global climate dynamics. However, rising CO₂ emissions from human activities have disrupted this balance, driving climate change and increasing the frequency of extreme weather events. Addressing this challenge requires strengthening natural carbon sinks, particularly forests, which store significant amounts of carbon in both biomass and soils. Sweet chestnut (Castanea sativa Mill.) coppice systems are promising for carbon sequestration due to their fast growth and potential for long-term carbon storage. Despite their ecological importance, many chestnut coppices remain unmanaged due to limited economic returns. Innovative strategies, such as payments for ecosystem services, could unlock their potential and enhance their contribution to climate change mitigation while promoting sustainable forest management.This study assesses the carbon sequestration and storage potential of sweet chestnut coppices using the CO₂FIX model, calibrated with field data from northeastern Portugal. The main objectives are to: Calibrate the CO₂FIX model to predict biomass and carbon stocks under different management practices. Validate model accuracy by comparing simulations with observed field data. Optimize parameterization to improved reliability for chestnut coppice systems. Identify growth constraints to support sustainable management strategies.
- CRISPR-CAS9 em plantas: desafios éticos, científicos e oportunidadesPublication . Choupina, Altino; Vieira, Kelly; Ferreira, PatrickA edição genómica por meio do sistema CRISPR-Ca9 representa um avanço significativo na biotecnologia, especialmente no melhoramento genético vegetal, ao permitir a modificação precisa dos genes específicos para enfrentar os desafios contemporâneos da agricultura. Este estudo tem como objetivo principal realizar uma revisão sistemática da literatura sobre o funcionamento da tecnologia CRISPR-Cas9, destacando as suas vantagens relativamente às técnicas anteriores e discutindo as suas aplicações na proteção vegetal, com ênfase no controlo de pragas, na resistência a stresse bióticos e abióticos, e no fortalecimento da imunidade vegetal. Além disso, o estudo visa refletir sobre os aspetos éticos, políticos e regulamentares envolvidos no uso dessa tecnologia. O trabalho está organizado da seguinte forma: Na Introdução apresenta-se a metodologia, objetivos e estrutura do presente estudo. No Capítulo I, apresentam-se os fundamentos do sistema CRISPR-Cas9, abordando a sua história, mecanismos de ação, além das suas aplicações médicas, farmacêuticas e agrícolas. Em seguida, no Capítulo II, explora-se o uso dessa tecnologia na proteção de plantas, analisando como as ferramentas moleculares de CRISPR-Cas9 são empregues para aumentar a resistência vegetal contra o stresse abióticos e bióticos. No Capítulo III, aprofunda-se a edição genómica de parasitas como insetos, fungos e oomicetes, discutindo o seu papel no controlo sustentável de pragas agrícolas. No Capítulo IV , introduz-se a técnica de RNA de interferência (RNAi), uma abordagem alternativa ao CRISPR-Cas9, destacando os seus avanços para conferir imunidade vegetal e resistência a stresse bióticos, além de comparar ambas as técnicas em termos de eficácia e aplicabilidade no melhoramento genético vegetal. Por fim, o Capítulo V examina as implicações éticas envolvidos na utilização de CRISPR-Cas9 na edição genómica, considerando questões relacionadas com a agricultura, segurança alimentar, impactos ambientais e socioeconómicos, bem como a aceitação pública e as políticas regulatórias em diferentes países. A Conclusão, reafirma a importância da tecnologia CRISPR-Cas9 no avanço do melhoramento vegetal, ao mesmo tempo que destaca a necessidade de mais estudos e debates para garantir o seu uso responsável e ético, considerando os desafios e as oportunidades para a agricultura global.
- Esperienze estere nella gestione dei castagneti da legno - Castanicoltura da legno in PortugalloPublication . Patrício, Maria SameiroLa coltivazione dei castagno in Portogallo ha unnruolo significativo sia a livello culturale che economico, occupando una superficie che supera i 48. 000 ha con impianti da frutto, denominati "soutos", boschi cedui (4.800 ha ca.) e fustaie per la produzione di legno. Visonoattualmentecirca 10.500 ha di nuovi impianti da legno governati a fustaia in proprietà private mentre il resto delle formazioni adulte di castagno ricadono principalmente su proprietà pubbliche la cui gestione è demandata ai Servizi Forestali: alie fustaie vengono applicati turni di 50-60 anni con conseguente conversione a ceduo dopo il primo taglio di utilizzazione; nei cedui il turno è di 20-25 anni e gli interventi di diradamento consentono di selezionare nel tempo due o tre polloni per ceppaia. Nonostante tali indicazioni, vi è un'evidente carenza nella realizzazione delle cure colturali sia nelle fustaie che nei cedui. II legno di castagno è tradizionalmente molto apprezzato in Portogallo, ma la produzione nazionale è insufficiente a soddisfare la richiesta dei mercato interno e notevole è 1'importazione dalla Francia. Migliorare la qualità dei legname prodotto rappresenta quinai un'opportunità sia per ridurre 1'importazione, sia per valorizzare la filiera dei prodotti non legnosi e fornire servizi aggiuntivi, quali ad esempio lo stoccaggio dei carbonio.
- Ex situ germination of European acorns: data from 93 batches of 12 Quercus speciesPublication . Medina, María; Reyes-Martín, Marino P.; Levy, Laura; Lázaro-González, Alba; Andivia, Enrique; Annighöfer, Peter; Assaad, Farhah; Bauhus, Jürgen; Benavides, Raquel; Böhlenius, Henrik; Cambria, Vito E.; Carbonero, María D.; Castro, Jorge; Chalatashvili1, Akaki; Chiatante, Donato; Cocozza, Claudia; Corticeiro, Sofia; Lazdina, Dagnija; Dato, Giovanbattista; Sanctis, Michele De; Devetaković, Jovana; Drossler, Lars; Ehrenbergerová, Lenka; Ferus, Peter; Gómez-Aparicio, Lorena; Hampe, Arndt; Hanssen, Kjersti H.; Heinze, Berthold; Jakubowski, Marcin; Jiménez, María N.; Kanjevac, Branko; Keizer, Jan J.; Kerkez-Janković, Ivona; Klisz, Marcin; Kowalkowski, Wojciech; Kremer, Klaus; Kroon, Johan; Montagna, Dario La; Lazarević, Jelena; Lingua, Emanuele; Lucas-Borja, Manuel E.; Łukowski, Adrian; Löf, Magnus; Maia, Paula; Mairota, Paola; Maltoni, Alberto; Mariotti, Barbara; Martiník, Antonín; Marzano, Raffaella; Matías, Luis; Mcclory, Ryan W.; Merino, Manuel; Mondanelli, Lucia; Montagnoli, Antonio; Monteverdi, Maria C.; Moreno-Llorca, Ricardo; Navarro, Francisco B.; Nonić, Marina; Nunes, Luís; Oliet, Juan A.; Patrício, Maria Sameiro; Poduška, Zoran; Popovic, Vladan; Puchałka, Radosław; Rey-Benayas, José M.; Robakowski, Piotr; Sewerniak, Piotr; Szczerba, Marek; Ureña-Lara, Carmen; Vendina, Viktorija; Villar-Salvador, Pedro; Witzell, Johanna; Leverkus, Alexandro B.Key message We provide data on seedlot germination potential—a key trait related to regeneration—of 12 oak species. Germination was tested at the University of Granada following international protocols with 8985 acorns from 93 batches and 16 countries across Europe. Data on germination probability, acorn origin, mass, and moisture content measured on another 4544 acorns are available at https:// doi. org/ 10. 30827/ Digib ug. 87318. Associated metadata are available at https:// metad ata- afs. nancy. inra. fr/ geone twork/ srv/ fre/ catal og. searc h#/ metad ata/ a742c 6d8- bc37- 4ca2- 8b81- 2447c 5a885 8d.
- Fluxos de CO2 do solo num espaço verde urbano: um estudo de caso durante a estação de primavera no norte de PortugalPublication . Silva, Alan Victor; Patrício, Maria Sameiro; Feliciano, ManuelGlobally cities account for more than 70% of CO2 emissions. The potential of urban green spaces as a biotechnology to reduce the net emissions is influenced by the type of vegetation and soil management. Thus, appropriate management of urban soils plays an important role in mitigating climate change, as it affects the biological processes responsible for carbon loss or gain in the soil. The knowledge about the carbon (C) sequestration capacity of grass soils in urban green spaces is still incipient. The study of soil CO2 fluxes is essential to implement more appropriate forms of mitigation in the management of areas with this type of ground vegetation cover. Therefore, this study aimed at investigating CO2 fluxes in a lawn area located in the city of Bragança. CO2 fluxes were measured continuously at a sampling interval of 30 minutes (total number of samples 5523) using the LI-8100A system from LI-COR Biosciences®, together with monitoring of edaphoclimatic and vegetative parameters, during the last month of winter and the tree months of spring. The results showed the importance of herbaceous vegetation in reducing CO2 emissions compared to those that would result from bare soil. However, throughout the observation period, the lawn surface acted as an emitting source with an average magnitude of 1.25 ± 5.31 g C m-2 d-1. The study allowed the identification of phytovolume and soil water availability as the most determining factors in this complex process that underlies the vertical fluxes that occurring at the surface/atmosphere interface. In this sense, management practices related to the frequency and amount of water used in irrigation, as well as the height and frequency of vegetation cutting were identified as key factors on the net exchange of CO2 on these lawn surfaces.
- Old and new climate change adaptation strategies by Montesinho mountain pastoralists, PortugalPublication . Aleixo-Pais, Isa G.; Castro, José; Frazão-Moreira, Amélia; Castro, João Paulo; Castro, MarinaMountain pastoralists are among the communities most affected by climate change, rendering empowerment of mountain communities and supportive policies essential.
- Perceptions and Challenges of Silvopastoralism in Trás-os-Montes: Insights from the Agricultural SectorPublication . Dias, Estefânia; Ribeiro, Maria Isabel; Castro, MarinaSilvopastoralism is a traditional land-use practice that integrates extensive livestock farming with forestry, generating both economic and environmental advantages. Over time, however, it has declined in relevance and the number of practitioners threatening its continuity and the ecosystem services it provides. This study aims to explore the perceptions of farmers and agricultural stakeholders in the Trás-os-Montes region concerning silvopastoral practices, while identifying the main barriers to their implementation and ways to encourage their adoption. A total of 60 anonymous surveys were carried out for this purpose. The results indicate that respondents see silvopastoralism as highly valuable in terms of wildfire prevention, biodiversity conservation, and sustainable natural resource management. It is particularly regarded as suitable for implementation in mature forest areas and regions with high levels of biomass. Nevertheless, several challenges hinder its adoption, including the lack of technical assistance, low economic returns, and limited awareness of existing research projects in this field. Another significant point raised by this research is the importance of preserving autochthonous livestock breeds, which are deeply connected to silvopastoral practices but increasingly at risk due to their decline. The study also emphasizes the urgent need to rethink rural land management models-especially by developing support mechanisms for producers who engage in silvopastoralism. The future of this practice in Trás-os-Montes will rely not only on the ability of farmers to adapt to modern-day challenges, but also on the broader societal recognition of its environmental benefits and the political will to strengthen and promote it.
- Promoting species diversity: understanding Sweet chestnut within regeneration of Scots pine standsPublication . Patrício, Maria Sameiro; Nunes, LuísPine forests show a natural gradual transition to mixed plantations where, with the progression of ecological succession, hardwoods such as Sweet chestnut (Castanea sativa Mill.) and oaks begin to progressively settle. However, the persistence of chestnut in conifer stands remains poorly studied and appears to be strongly influenced by the surrounding areas where the species is cultivated and light availability. In this case study conducted in Serra da Nogueira, Portugal, which is characterized by a mosaic of habitats resulting from mountain agriculture, including extensive Pyrenean oak forests and stands of other hardwoods and conifers, such as Scots pine (Pinus sylvestris L.), it was observed that chestnut persisted in the natural regeneration of these stands primarily due to the presence of nearby chestnut forests and agroforestry stands. The presence of advanced regeneration in the understory of Scots pine stands suggests that chestnut can persist in the natural regeneration dynamics, leading to the formation of mixed stands more resilient and biodiverse. Therefore, the regeneration status of two Scots pine stands covering a 12-hectare area in Serra da Nogueira (41°45'34"N, 6°54'53"W, altitude 980 m) was assessed. A systematic sampling approach was applied. A semi-permanent circular plot device was installed, following a concentric system with a fixed radius. Natural regeneration (d<10 cm) was divided into two height strata: up to 2 m and > 2 m. Concentric circular plots of 100 and 200 m2 wereused to study each height stratum. Abundance and diversity were evaluated using modified Shannon and Simpson indices, the inverse of the Berger-Parker index, and species richness. Generalized linear models (GLM) and generalized additive models (GAM) were employed to explore the influence of potential explanatory variables related to stand structure, crown cover, and degree of shrub cover (SC)on the abundance of the main species contributing to natural regeneration. The results indicate that basal area (G) significantly affects the abundance of natural regeneration. Additionally, it was found that the percentage of SC also had an influence. Basal areas close to 40 m2 ha-1 promote the regeneration of Scots pine while lower G favors the establishment of hardwoods, particularly chestnut.
- Promoting species diversity: understanding Sweet Chestnut within regeneration of Scots pine standsPublication . Patrício, Maria Sameiro; Nunes, LuísPine forests exhibit a natural gradual transition to mixed plantations, where hardwoods like sweet chestnut (Castanea sativa Mill.) and oaks begin to establish as ecological succession progress. However, the persistence of chestnut in conifer stands depends heavily on surrounding chestnut stands and light availability. In this case-study of Serra da Nogueira, Portugal – a region characterized by a mosaic of habitats formed by mountain agriculture, with extensive Pyrenean oak forests interspersed with some stands of other hardwoods and conifers, including scots pine (Pinus sylvestris L.) - chestnut persists in the natural regeneration of these stands largely due to existing forest and agroforestry chestnut stands. Advanced regeneration in the understory of Scots pine stands suggests that the chestnut can persist in the natural regeneration dynamics, contributing to the formation of more resilient and biodiverse mixed stands.
- Sequestro de carbono em castinçais: impacto da densidade de varas simulado com o modelo CO2FixPublication . Patrício, Maria Sameiro; El Baine, Chaimae; Nunes, LuísAs talhadias de castanheiro (Castanea sativa Mill.) podem potenciar o sequestro de carbono, contribuindo para a mitigação das alterações climáticas. Neste contexto, o presente estudo avaliou o potencial de sequestro de carbono em diferentes densidades de varas por touça, recorrendo ao modelo CO2Fix. O ensaio foi conduzido em Cimas de Mogadouro, no Nordeste de Portugal e compreendeu quatro tratamentos, avaliados ao longo de 12 anos. O modelo foi calibrado para simular a produção de biomassa e o correspondente sequestro de carbono numa rotação de 42 anos. Os tratamentos com três (T2) e cinco (T3) varas revelaram maior acumulação de biomassa e carbono, sobretudo na biomassa aérea e raízes. O tratamento T2 destacou‑se pelo maior acréscimo corrente anual e pela produção de varas com maiores diâmetros conferindo-lhes potencial de armazenamento de carbono em produtos de longa duração. A modelação mostrou‑se consistente nos tratamentos T1, T2 e T3, embora tenha subestimado o carbono no tratamento T4 (alto fuste) nas fases iniciais. Os resultados confirmam que, através de práticas silvícolas ajustadas, os castinçais funcionam como sumidouros de carbono eficientes, promovendo uma gestão florestal sustentável.