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Abstract(s)
Os microrganismos presentes no solo desempenham um papel fundamental na
manutenção dos ecossistemas terrestres, regulando e fornecendo nutrientes às plantas. O
seu desequilíbrio pode afectar significativamente a comunidade vegetal, impactando a
abundância, saúde e qualidade do solo. O castanheiro europeu (Castanea sativa Mill.) é
vital para a economia de algumas regiões da Europa, especialmente o norte de Portugal,
devido à produção de fruto e madeira. As alterações edafoclimáticas podem interferir
directamente na produtividade do castanheiro, na biodiversidade associada e nos seus
ecossistemas. O presente trabalho pretendeu estudar o efeito das condições
edafoclimáticas na biodiversidade microbiana do solo em dois soutos de demonstração
localizados no distrito de Bragança (Parada e Salgueiros). As amostras de solo foram
colhidas em cada souto demonstração em três períodos do ano (primavera, verão e
outono) a uma profundidade de 0-20 cm, tendo sido analisados parâmetros físico-
químicos (pH, teor de humidade, carbono orgânico, fósforo, potássio e bases de troca) e
microbiológicos, designadamente a respiração basal do solo, carbono da biomassa
microbiana , azoto da biomassa microbiana, assim como a quantificação de bactérias e
fungos. A composição da comunidade bacteriana e fúngica das amostras de solo foi
avaliada por sequenciamento de nucleótidos das regiões 16S RNA e ITS(ITS1‐ITS2),
respetivamente, com a plataforma Illumina MiSeq. Os resultados revelaram diferenças
entre locais, sobretudo nos valores de pH e nos teores de C orgânico. O souto de Parada
apresentou valores de pH(H2O) (5,84) e teores de Carbono orgânico (18,99 g kg-1) mais
elevados relativamente ao souto de Salgueiros, 5,11 e 11,84 g kg-1, respetivamente. Os
valores de carbono microbiano, azoto micribiano e a respiração basal do solo variaram
sazonalmente, sendo essas variações mais expressivas no souto de menor altitude
(Parada). A diferenciação entre locais manifestou-se também na abundância e
composição da comunidade bacteriana e fúngica. O souto demonstração de Salgueiros
(maior altitude) apresentou maior estabilidade das populações bacterianas e fúngicas ao
longo das estações. As famílias bacterianas Acidobacteraceae e Xanthobacteraceae foram
as mais frequentes e com maior predominância em ambos os locais e nas três épocas
avaliadas, bem como a família fúngica Trimorphomycetaceae. A maior diferenciação
entre locais verificou-se com as famílias Pleosporaceae e Phaeosphaeriaceae que
ocorreram apenas em Parada.
Soil microorganisms play a fundamental role in maintaining terrestrial ecosystems by regulating and providing nutrients to plants. Their imbalance can significantly affect plant communities, impacting the abundance, health, and quality of the soil. The European chestnut (Castanea sativa Mill.) is crucial for the economy of certain regions of Europe, especially in northern Portugal, due to its fruit and timber production. Edaphoclimatic changes can directly interfere with the productivity of chestnut trees, the associated biodiversity, and their ecosystems. This study aimed to investigate the effect of edaphoclimatic conditions on soil microbial biodiversity in two demonstration chestnut orchards located in the district of Bragança (Parada and Salgueiros). Soil samples were collected from each demonstration site during three seasons (spring, summer, and autumn) at a depth of 0-20 cm, and analyzed for physicochemical parameters (pH, moisture content, organic carbon, phosphorus, potassium, and exchangeable bases) and microbiological parameters, including soil basal respiration, microbial biomass carbon, and microbial biomass nitrogen, as well as the quantification of bacteria and fungi. The composition of the bacterial and fungal communities in the soil samples was assessed by nucleotide sequencing of the 16S rRNA and ITS (ITS1‐ITS2) regions, respectively, using the Illumina MiSeq platform. The results revealed differences between the sites, particularly in pH values and organic carbon content. The Parada orchard exhibited higher pH(H2O) values (5.84) and organic carbon content (18.99g kg-1) compared to the Salgueiros orchard, which had values of 5.11 and 11.84 g kg-1, respectively. The values of microbial carbon, microbial nitrogen, and soil basal respiration varied seasonally, with more pronounced variations observed at the lower altitude site (Parada). The differentiation between sites was also evident in the abundance and composition of bacterial and fungal communities. The Salgueiros demonstration site (higher altitude) showed greater stability of bacterial and fungal populations throughout the seasons. The bacterial families Acidobacteraceae and Xanthobacteraceae were the most frequent and dominant across both locations and throughout the three seasons studied, as well as the fungal family Trimorphomycetaceae. The greatest differentiation between the sites was observed with the fungal families Pleosporaceae and Phaeosphaeriaceae, which were found only in Parada.
Soil microorganisms play a fundamental role in maintaining terrestrial ecosystems by regulating and providing nutrients to plants. Their imbalance can significantly affect plant communities, impacting the abundance, health, and quality of the soil. The European chestnut (Castanea sativa Mill.) is crucial for the economy of certain regions of Europe, especially in northern Portugal, due to its fruit and timber production. Edaphoclimatic changes can directly interfere with the productivity of chestnut trees, the associated biodiversity, and their ecosystems. This study aimed to investigate the effect of edaphoclimatic conditions on soil microbial biodiversity in two demonstration chestnut orchards located in the district of Bragança (Parada and Salgueiros). Soil samples were collected from each demonstration site during three seasons (spring, summer, and autumn) at a depth of 0-20 cm, and analyzed for physicochemical parameters (pH, moisture content, organic carbon, phosphorus, potassium, and exchangeable bases) and microbiological parameters, including soil basal respiration, microbial biomass carbon, and microbial biomass nitrogen, as well as the quantification of bacteria and fungi. The composition of the bacterial and fungal communities in the soil samples was assessed by nucleotide sequencing of the 16S rRNA and ITS (ITS1‐ITS2) regions, respectively, using the Illumina MiSeq platform. The results revealed differences between the sites, particularly in pH values and organic carbon content. The Parada orchard exhibited higher pH(H2O) values (5.84) and organic carbon content (18.99g kg-1) compared to the Salgueiros orchard, which had values of 5.11 and 11.84 g kg-1, respectively. The values of microbial carbon, microbial nitrogen, and soil basal respiration varied seasonally, with more pronounced variations observed at the lower altitude site (Parada). The differentiation between sites was also evident in the abundance and composition of bacterial and fungal communities. The Salgueiros demonstration site (higher altitude) showed greater stability of bacterial and fungal populations throughout the seasons. The bacterial families Acidobacteraceae and Xanthobacteraceae were the most frequent and dominant across both locations and throughout the three seasons studied, as well as the fungal family Trimorphomycetaceae. The greatest differentiation between the sites was observed with the fungal families Pleosporaceae and Phaeosphaeriaceae, which were found only in Parada.
Description
Keywords
Castanea sativa Mill. Carbono microbiano Respiração do solo Azoto microbiano Bactérias Fungos