Maize crop response to different levels of mineral and or-ganomineral fertilization associated with plant growth promoting bacteria (PGPBs): Resposta da cultura do milho a diferentes níveis de adubação mineral e organomineral associada à bactérias promotoras do crescimento de plantas (BPCPs)

Corn has a high nutritional requirement, especially with regard to NPK fertilization. However, the low efficiency of conventional fertilizers combined with the high cost of the input has limited the reach of high yields. The use of fertilizers with increased efficiency seeks to mitigate these limitations, reducing potential losses due to the gradual release of nutrients. The objective of this work was to compare the nutrition, growth and production of maize plants subjected to different doses and special NPK fertilizers fully applied at planting, as well as their residual effect on the soil. A randomized block design was used, in a 3 x 4 factorial scheme, with four replications. The first factor consisted of conventional mineral, polymer coated and organomineral fertilizers inoculated with PGPBs. The second factor was doses of 0, 60, 90 and 120 kg ha-¹ of NPK. Vegetative growth, foliar nutrition (N, P and K), yield growth components, productivity, profitability and P and K nutrient content remaining in the soil after cultivation were evaluated. The conventional mineral fertilizer presented higher production of dry biomass of the aerial part and profitability in relation to the special fertilizers. However, the special fertilizers presented better results in the vegetative and productive growth, in general, still showing a potential reduction of the applied doses, without compromising the grain yield, especially in the organomineral fertilization + PGPBs. The same showed greater residual effect of K in the soil, proving to be relevant longterm studies for better elucidation of these effects in the soil and subsequent culture

Construção e validação de uma mesa de tensão de baixo custo

Richards Pressure Chamber is the most traditional method and considered standard for determining soil water retention stresses, however, has the disadvantage of high acquisition cost. The tension table is alternative equipment for the low cost of this method and varied construction. The objective of this study was to construct a low cost tension table and easy assembly comparing it with the Richards Pressure Chamber using soil samples from different cultivation systems, being extensive grazing, rotated grazing, corn cultivation, Tifton cultivation, sugar cane cultivation and natural forest (control), submitted to 2, 4, 6, 8, 10 e 12 kPa water retention. Were analyzed the densities, granulometry and organic matter of the soil. The area under Tifton cultivation, even with the highest organic matter content, promoting soil compaction resistance, presented higher soil density, followed by rotational grazing. This fact can be explained by the heavy traffic in irrigated area without the control of the applied load on the ground and the inadequate water management. Excessive animal load for rotational grazing without the concern for the applied pressure, caused the highest soil density. Low cost tension table values were different from Richards pressure chamber, been the correction factor required to use the equipament accurately.A câmara de pressão de Richards é o método mais tradicional e considerado padrão para determinar as tensões de retenção de água no solo, porém detém da desvantagem do elevado custo de aquisição. A mesa de tensão é um equipamento alternativo para este método, sendo de baixo custo e construção variada. Objetivou-se neste estudo construir uma mesa de tensão de baixo custo e fácil montagem para determinação da tensão de retenção de água no solo, comparando-a posteriormente à câmara de pressão de Richards utilizando amostras de solo de diferentes sistemas de cultivo, pastejo extensivo, pastejo rotacionado, cultivo de milho, cultivo de tifton, cultivo de cana-de-açúcar e mata natural (controle), submetidas às tensões de água de 2, 4, 6, 8, 10 e 12 kPa. Foram analisadas densidade, granulometria e teor de matéria orgânica do solo. A área sob cultivo de tifton, mesmo com o maior teor de matéria orgânica, promotor da resistência do solo à compactação, apresentou maior densidade do solo, seguida pelo pastejo rotacionado. Este fato pode ser explicado pelo intenso tráfego de máquinas em área irrigada sem o controle da carga aplicada no solo e o manejo inadequado da água. Os valores obtidos da mesa de tensão de baixo custo foram diferentes daqueles da câmara de pressão de Richards e entre os sistemas estudados, sendo necessário a aplicação do fator de correção de 1,41 e 1,42 nas tensões de 6 e 10 kPa, respectivamente, para utilizar o equipamento com precisão

Interaction soil compaction and soil moisture in physiological responses of freshly planted coffee

In the field, coffee is subject to the stress of soil compaction and lack of water, which may cause changes in the physiological responses of the plant. The objective of this study was to evaluate the physiological responses of the coffee tree under different soil moisture content and compaction degrees in the soil subsurface. The experimental design was in blocks, arranged in a factorial scheme, with four replications. The first factor corresponds to the two wetlands, 50 and 100% of the soil field capacity. The second factor corresponds to 60, 70, 80 and 90% of soil subsurface compaction. The experimental plot consisted of a Coffea arabica L. plant grown on a polyvinyl chloride column. The physiological responses were evaluated at 180 days of planting. The photosynthetic rate, carbon consumption, CO2 concentration in the substamatic chamber, internal carbon / atmospheric carbon ratio, water efficiency and absolute coffee growth rate were influenced by the different compaction degrees and soil moisture content. The transpiration rate and the root weight ratio were influenced only by the humidity, as opposed to the stomatal conductance and the foliar temperature, which were by degrees of compaction. The ratio of root system per soil layer was influenced by compaction degrees and soil depth. The limitation of root growth and lack of water are the main causes of the decrease in physiological responses. Subsurface compaction and water deficit together potentiate the effect negatively on the physiological responses of freshly seeded coffee plants.In the field, coffee is subject to the stress of soil compaction and lack of water, which may cause changes in the physiological responses of the plant. The objective of this study was to evaluate the physiological responses of the coffee tree under different soil moisture content and compaction degrees in the soil subsurface. The experimental design was in blocks, arranged in a factorial scheme, with four replications. The first factor corresponds to the two wetlands, 50 and 100% of the soil field capacity, and the second corresponds to 60, 70, 80, and 90% of soil subsurface compaction. The experimental plot consisted of a Coffea arabica L. plant grown on a polyvinyl chloride column. The physiological responses were evaluated at 180 days of planting. The different compaction degrees and soil moisture content influenced the photosynthetic rate, carbon consumption, CO2 concentration in the substomatal chamber, internal carbon / atmospheric carbon ratio, water efficiency, and absolute coffee growth rate. The transpiration rate and the root weight ratio were influenced only by the humidity, instead of the stomatal conductance and the foliar temperature, by degrees of compaction. The ratio of root system per soil layer was influenced by compaction degrees and soil depth. The limitation of root growth and lack of water are the main causes of decreased physiological responses. Subsurface compaction and water deficit together potentiate negatively on the physiological responses of freshly seeded coffee plants

Produção e qualidade de beterrabas submetidas a diferentes manejos de adubação e efeito residual na produção de milho cultivado em sucessão

A prática do cultivo de milho sucessivo à beterraba tem apresentado retornos econômicos positivos aos produtores, sendo um dos fatores primordiais para o sucesso da atividade, a adubação. O estudo objetivou avaliar diferentes manejos de adubação nos aspectos quantitativos e qualitativos na cultura da beterraba, bem como seus efeitos residuais no cultivo do milho plantado em sucessão. O experimento foi conduzido no município de Diamantina-MG, em casa de vegetação, sob delineamento em blocos casualizados, com sete tratamentos, sendo controle (sem adubação), mineral, organomineral peletizado NPK 04-17-07 nas doses de 40, 80, 160 e 320% da recomendação para a cultura da beterraba, com quatro repetições. Avaliou-se altura de plantas, diâmetros longitudinal e transversal das raízes, clorofila A e B, peso de massa fresca e seca da parte aérea e raízes, produtividade, teor de sólidos solúveis e o tempo de prateleira. Na segunda etapa experimental, verificou-se o número de espigas por planta, peso por espiga, peso do sabugo, peso de 100 grãos e estimada a produtividade. Os dados foram submetidos à análise de variância e ao teste Tukey (p < 0,05) para comparação de médias. A análise de regressão foi feita diante as doses do fertilizante organomineral para produtividade de ambas as culturas. A utilização do fertilizante organomineral peletizado e torta de filtro no plantio proporcionam efeitos positivos ao desenvolvimento e produção de plantas de beterraba assim como para o milho em sucessão, mostrando-se alternativas viáveis à adubação mineral neste sistema

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

AMAZONIA CAMTRAP: A data set of mammal, bird, and reptile species recorded with camera traps in the Amazon forest

The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed, and gray literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive data set of inventories of mammal, bird, and reptile species ever assembled for the area. The complete data set comprises 154,123 records of 317 species (185 birds, 119 mammals, and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname, and Venezuela). The most frequently recorded species per taxa were: mammals: Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles: Tupinambis teguixin (716 records). The information detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change, and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when using its data in publications and we also request that researchers and educators inform us of how they are using these data