Invasive macrophytes are considered problematic in natural environments and hydroelectric reservoirs. Climate changes, the occurrences of watercourses, and biotic interactions influence biological invasions of macrophytes. The abundance of native species can be positively or negatively correlated with the occurrences of invasives. Urochloa subquadripara is an invasive in natural or disturbed habitats co-occurring with the natives Eichhornia crassipes and Salvinia minima in South America. Aquatic plant communities can be altered by climate change, so species distribution models (SDMs) are important tools for predicting invaded areas. This study aimed to apply an SDM to study correlations of U. subquadripara with the potential distributions of native species E. crassipes and S. minima. Occurrence data for U. subquadripara, E. crassipes, and S. minima were collected from databases and in consultation with the published literature. Parameters encompassing biological information of the species were entered into the CLIMEX software and used to generate the Ecoclimatic Index (EI). The species co-occurrence was performed based on multicriteria decision-making (MCDM), and weights were assigned using the analytical hierarchy process (AHP). It was observed that U. subquadripara, E. crassipes, and S. minima had a higher occurrence in tropical and subtropical regions. However, it is predicted that these species may move to high latitudes from climatic changes. Considering climate changes, such as the increase in temperature and CO₂, the risk of invasion by U. subquadripara in the northern hemisphere is mainly in lakes, whereas the areas conducive to invasions are rivers and reservoirs in the southern hemisphere. In general, emerging and floating macrophyte species such as U. subquadripara, E. crassipes, and S. minima will be favored, causing suppression of submerged species. Therefore, identifying the potential distribution of these species allows the creation of pre-invasion intervention strategies.

Capim dourado, also known as sedinha, refers to the everlasting flower Syngonanthus nitens (Bong.) Ruhland (Eriocaulaceae), prized for its use in crafting and as a significant income source for communities in Minas Gerais, Bahia, and Tocantins, Brazil. This plant is also utilized in the creation of highly valued jewelry and accessories on the global market. This study aims to ascertain the thermal and humidity thresholds of S. nitens while mapping and predicting its current and future distribution. Initially, distribution data was gathered through a literature review, supplemented by biological temperature and humidity data collected from the Quilombola Raiz Community in Minas Gerais and a germination experiment conducted at the Integrated Multi-User Research Laboratory of the Jequitinhonha and Mucuri Valleys (LIPEMVALE). Climate Index (CLIMEX) parameters were defined using biological information and occurrence locations. The optimal temperature range for S. nitens development is between 18 and 24 °C, with minimum and maximum thresholds of 5 °C and 40 °C respectively. Ninety-two occurrence records were found, all situated in South America, aligning with high climate suitability regions as per the model predictions. Future projections for 2050 and 2100 indicate a decrease in areas suitable for S. nitens. These findings provide crucial insights for decision-making, necessitating measures such as widespread monitoring, collaborative conservation efforts, and the establishment of sustainable use zoning to manage S. nitens effectively.

Invasive macrophytes are considered problematic in natural environments and hydroelectric reservoirs. Climate changes, the occurrence of watercourses, and biotic interactions influence the biological invasion of macrophytes. Native species can correlate with invasives positively or negatively. Urochloa subquadripara is an invasive in natural or disturbed habitats co-occurring with the natives Eichhornia crassipes and Salvinia minima. Aquatic plant communities can be altered by climate change, so species distribution models (SDMs) are important tools for predicting in-vaded areas. This work aimed to make an SDM for U. subquadripara correlating with the poten-tial distribution of native species E. crassipes and S. minima. Occurrence data for U. subquadripara, E. crassipes, and S. minima were collected from databases and in consultation with the published literature. Parameters encompassing biological information of the species were entered into the CLIMEX software and used to generate the Ecoclimatic Index (EI). The species co-occurrence was performed based on multicriteria decision-making (MCDM), and weights were assigned using the analytical hierarchy process (AHP). It was observed that U. subquadripara, E. crassipes, and S. minima have a higher occurrence in tropical and subtropical regions; however, it is predicted that, from climatic changes, these species may move to high latitudes. According to climate change, the risk of invasion by U. subquadripara in the northern hemisphere is mainly in lakes, while in the southern hemisphere, the areas conducive to invasions are rivers and reservoirs. In general, emerging and floating macrophyte species such as U. subquadripara, E. crassipes, and S. minima will be favored, causing suppression of submerged species. Therefore, identifying the potential distribution of these species allows the creation of pre-invasion intervention strategies.

A competição com plantas daninhas por água ou luz pode afetar parâmetros fisiológicos das culturas de interesse. A partir desse estudo, objetivou-se avaliar o efeito da umidade do solo e a competição de duas espécies de plantas daninhas em diferentes combinações nas características fisiológicas de plantas de eucalipto. O delineamento experimental utilizado foi ao acaso com quatro repetições em esquema fatorial 4 x 4. O primeiro fator correspondeu às combinações de plantas do híbrido clonal de eucalipto cultivadas em competição com picão-preto e braquiária: 1 - Uma planta de eucalipto + duas plantas de braquiária por vaso; 2 - Uma planta de eucalipto + duas de picão-preto por vaso; 3 - Uma planta de eucalipto + uma planta de picão-preto + uma planta de braquiária por vaso, e; 4 - uma planta de eucalipto por vaso. O segundo correspondeu aos níveis de água no solo: 100, 74, 67 e 60% da capacidade de campo. Foram feitas avaliações dos teores de clorofila a, b, a/b e total, bem como, variáveis relacionadas a fluorescência da clorofila. O eucalipto crescendo isoladamente mostrou maiores valores de clorofila a clorofila b e clorofila total. A relação clorofila a/ b foi inferior em todos os níveis de umidade do solo. A fluorescência inicial mostrou tendência de decréscimo com o aumento da umidade. Nas menores umidades testadas as plantas de eucalipto se encontravam em condição de estresse com valores de fluorescência variável/fluorescência máxima inferiores a 0,75.

Soybean ( Glycine max (L.) Merril) yield in tropical high‐altitude regions is strongly influenced by soil physical and chemical attributes, particularly in highly weathered oxisols, where variability among suborders may affect crop performance. This study aimed to identify the physical and chemical soil factors associated with the productive performance of soybean cultivars grown in different Oxisol suborders in tropical high‐altitude environments. The study was conducted in Cabeceira Grande, Minas Gerais, Brazil, within the Cerrado biome. Three field experiments were carried out under a no‐tillage system during the 2019/2020 growing season, each established on a distinct soil class: Typic Hapludox, Xanthic Hapludox, and Rhodic Hapludox. Four soybean cultivars (Desafio, NS6906, NS7901, and RK6316) were evaluated using a randomized block design with four replications. Soil samples were collected at depths of 0–20, 20–40, and 40–60 cm and analyzed using exploratory statistics and principal component analysis in association with soybean morphophysiological traits and yield components. The physical and chemical characterization of oxisols allowed clear discrimination among soil suborders. The cultivar NS7901 showed higher grain yield across all Oxisol suborders. Additionally, Rhodic Hapludox showed higher grain yield than the other soil classes, irrespective of cultivar. Soil chemical attributes at the 20‐ to 40‐cm depth were strongly associated with specific soybean yield components. These results highlight the importance of subsurface soil chemical attributes in explaining soybean yield variability in tropical oxisols and provide valuable insights for soil‐specific management strategies to improve soybean productivity in high‐altitude tropical regions.