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- Contributo para o conhecimento da agrodiversidade no concelho de Santa Cruz, MadeiraPublication . Carvalho, Miguel A. A. Pinheiro de; Ragonezi, Carla; Macedo, Fabrício Lopes de; Antunes, Gonçalo; Freitas, Gregório; Nóbrega, HumbertoO presente trabalho procura analisar as alterações sofridas pela agrodiversidade no território do Santa Cruz. Este concelho localizado na costa sul da Madeira tem 81,5 km2, quatro patamares bioclimáticos e numerosas unidades agroecológicas (UAE). A evolução da agrodiversidade iniciou-se, com o povoamento do Arquipélago, descoberto inabitado em 1418. A agrodiversidade biofísica, específica e intraespecífica aumentou e diversificou-se, devido à construção de agrossistemas, introdução de culturas, sucessão de ciclos agrícolas, adaptação às condições agroecológicas, aparecimento de pragas e doenças e pela ação do homem. Os registos históricos indicam a introdução de um elevado número de culturas, bem como a utilização de 72 espécies agrícolas, no concelho. E, indicam como fundamentais no povoamento e economia as culturas do trigo e as cerealíferas (cevada, centeio), cana-sacarina, vinha e sumagre. Várias outras culturas desempenharam um papel importante na economia do concelho, sendo cultivadas para fins alimentares, comerciais, industriais, culturais ou religiosos. A adaptação destas espécies aos agrossistemas e às condições agroecológicas deu origem a um número indeterminado de variedades locais. Apesar das limitações da documentação disponível, foram encontradas referências a variedades locais cuja cultura remonta há 140 a 500 anos, nomeadamente o Trigo da Serra, castas Malvasia e Tinta Antiga de Gaula, pêra Caniça, Banana da terra, feijão Corno de carneiro e Couve de João Ferino, que podem ser relacionadas com o historial do concelho. Porém, desde meados do século XX, a agrodiversidade sofreu uma drástica redução com a diminuição das áreas cultivadas, o abandono de várias espécies agrícolas e a extinção de variedades locais. A análise desta agrodiversidade foi realizada, a fim de apurar as alterações históricas e geográficas ocorridas na agrodiversidade em onze culturas representativas do concelho, visando a sustentabilidade agronómica.
- Structure and floristic composition associated with an endangered species Beta patula Aiton (Amaranthaceae) in the Islands of Madeira ArchipelagoPublication . Nóbrega, Humberto; Freitas, Gregório; Zavattieri, M. A.; Ragonezi, Carla; Carvalho, Miguel Â. A. Pinheiro deTwenty-two native Crop Wild Relatives (CWR) occur in specific dry environments of Madeira Archipelago, like Desembarcadouro islet in Ponta de São Lourenço and Chão islet in Desertas Islands. Nine of them share the same gene pool with crop species included in Annex I of the International Treaty on Plant Genetic Resources for Food and Agriculture. Amongst them, Beta patula Aiton, an IUCN Critically Endangered species, has been studied in detail for in situ and ex situ conservation. The present paper summarises the information recorded during the Beta patula population assessment. Valuable information on plant communities associated with this species was obtained.
- Anticipating the Climate Change Impacts on Madeira’s Agriculture: The Characterization and Monitoring of a Vine AgrosystemPublication . Carvalho, Miguel Â. A. Pinheiro de; Ragonezi, Carla; Oliveira, Maria Cristina O.; Reis, Fábio; Macedo, Fabrício Lopes; Freitas, José G. R. de; Nóbrega, Humberto; Ganança, José Filipe T.Climate—Madeira Strategy (CMS) foresees two models to describe the climate scenarios for the Madeira region in 2050 and 2070. These scenarios anticipate an average temperature rise of 1.4 to 3.7 ◦C and a decrease in precipitation by 30 to 40%. Consequently, Madeira’s agriculture will suffer the impacts of climate change. To understand these impacts, a baseline of major agrosystem components needs to be established, with the ultimate goal to monitor its consequences in its functioning. CASBio project used the 1961–1991 and 2010–2020 meteorological data series to modulate climate conditions and characterize and monitor six agrosystems for 2 years. One of them was a vineyard, Quinta das Vinhas, representing a typical agrosystem in the Mediterranean climate. The annual and seasonal variation in climatic parameters, soil conditions, microbiological communities, floristic and insect diversity, and crop production was assessed, using a total of 50 parameters. The results were used to establish a baseline of the agrosystem components and their seasonal and annual variation. The major findings are: (i) winter and summer extreme events show a trend in temperature and precipitation supporting a fast change in climate; (ii) a critical imbalance between nitrogen fixing and denitrifying bacteria was identified, especially in summer, that could be determined by the rise in temperature and drought; (iii) among floristic diversity, the therophytes and geophytes confirm to be the most suitable indicators for the rise in temperature and reduction in precipitation in the agrosystems; (iv) an imbalance in favor of C. capitata plague was observed, associated with the summer rise in temperature and decrease in precipitation; (v) despite an increase in most of the grape varieties production, the Madeiran wine local varieties were shown to be less stable in productivity under observed climate conditions. The agrosystem baseline is a starting point for long term monitoring and allows for further quantifying the influence of climate change on agrosystem productivity, resilience, and sustainability.
- Estimation of Productivity and Above-Ground Biomass for Corn (Zea mays) via Vegetation Indices in Madeira IslandPublication . Macedo, Fabrício Lopes; Nóbrega, Humberto; Freitas, José G. R. de; Ragonezi, Carla; Pinto, Lino; Rosa, Joana; Carvalho, Miguel A. A. PinheiroThe advancement of technology associated with the field, especially the use of unmanned aerial vehicles (UAV) coupled with multispectral cameras, allows us to monitor the condition of crops in real time and contribute to the field of machine learning. The objective of this study was to estimate both productivity and above-ground biomass (AGB) for the corn crop by applying different vegetation indices (VIs) via high-resolution aerial imagery. Among the indices tested, strong correlations were obtained between productivity and the normalized difference vegetation index (NDVI) with a significance level of p < 0.05 (0.719), as well as for the normalized difference red edge (NDRE), or green normalized difference vegetation index (GNDVI) with crop productivity (p < 0.01), respectively 0.809 and 0.859. The AGB results align with those obtained previously; GNDVI and NDRE showed high correlations, but now with a significance level of p < 0.05 (0.758 and 0.695). Both GNDVI and NDRE indices showed coefficients of determination for productivity and AGB estimation with 0.738 and 0.654, and 0.701 and 0.632, respectively. The use of the GNDVI and NDRE indices shows excellent results for estimating productivity as well as AGB for the corn crop, both at the spatial and numerical levels. The possibility of predicting crop productivity is an essential tool for producers, since it allows them to make timely decisions to correct any deficit present in their agricultural plots, and further contributes to AI integration for drone digital optimization.
- Distribution of Genetic Diversity in Beta patula Aiton Populations from Madeira Archipelago, PortugalPublication . Ragonezi, Carla; Nóbrega, Humberto; Leite, Maria Inês; Freitas, José G. R. de; Macedo, Fabrício Lopes; Carvalho, Miguel Â. A. Pinheiro deBeta patula Aiton is a crop wild relative (CWR) which belongs to the Gene Pool 1b and is considered a Critically Endangered species, and is present in very specific environments, such as the Desembarcadouro islet (DI) in Ponta de São Lourenço or Chão islet (CI) in the Desertas Islands. The ISOPlexis Center (University of Madeira) has been providing continuous support for its in situ conservation by keeping a management plan of wild populations and an ex situ conservation strategy through the storage of accessions in the ISOPlexis GeneBank. The present work intends to present the spatial distribution of genetic variability and diversity in these B. patula populations using eight polymorphic Simple Sequence Repeat (SSR) markers. The overall results lead to the identification of three spots with a high genetic diversity. CI with a small cluster of individuals shows a genetic footprint different from DI, having unique alleles present in its population. DI has two distinct areas: the western area, with a higher individual density but with a lower genetic diversity and higher allele fixation; and the central area, with a lower individual count but with a higher genetic diversity and with the presence of unique alleles. Despite some genetic differences, the comparison of the two islets’ DI and CI populations shows that they have more similarities than differences. Analysis of the Molecular Variance, based on the hierarchical cluster, showed a 9% diversity between populations, 68% among individuals, and 23% within individuals. This data will be used for the establishment of a protocol to monitor and manage B. patula genetic diversity under a genetic reserve, subsequently contributing to the European Genetic Reserve network implementation and the protection of this important CWR.