ABSTRACT The use of organic fertilizers from pig slurry and poultry litter can increase soil organic carbon and crop productivity. This study aimed to evaluate soil organic carbon fractions and corn yield after applying organic and mineral fertilizers. The experiment was conducted in the western region of Santa Catarina State, southern Brazil on a Nitossolo Vermelho Eutroférrico típico (Rhodic Kandiudox). The production system was an integrated crop-livestock using corn and soybean in the summer and black oat and rye with grazing by sheep in the winter. The experimental design was randomized blocks, with treatments in factorial 5 × 3 + 1, with four replications, five sources of fertilizers, three rates and the control with no fertilization. The treatments were three organic fertilizers: poultry litter, pig slurry and compost from pig slurry and two minerals fertilizer (M1 and M2). Mineral fertilizers were formulated from pig slurry (M1) and poultry litter (M2), with the application of three rates, which represent 75, 100 and 150 % of the recommendation for the crop, based on the element that is most demanding by the plant (K for soybeans and N for corn). Soil samples were collected at the layers of 0.00-0.05, 0.05-0.10 and 0.10-0.20 m in which fractions of total soil organic carbon (TOC), namely particulate (POC) and mineral-associated organic carbon (MAC) were determined. Corn yield was evaluated in the 2018/2019 and 2019/2020 seasons. The results were analyzed through analysis of variance to compare sources and polynomial regression analysis for fertilizer rates. The MAC fraction has a higher proportion of TOC and its contents were higher with increasing rates of organic and mineral fertilizers, mainly in the surface layer. Poultry litter and compost fertilizers increased TOC’s particulate fraction (POC), showing the highest levels at the highest fertilization recommendation rate. Organic and mineral fertilizers positively increase corn yield, and animal-derived fertilizers show that they can be an alternative for high crop yields.

ABSTRACT Cultivated soils, when submitted to agricultural practices, tend to compact due to the pressure exerted by agricultural machines and implements, a process that compromises soil quality and system sustainability. Specific properties of each soil, such as particle size and organic matter content, interfere with the process and degree of compaction and, consequently, plant growth. This study aimed to analyze the effect of different degrees of compaction (DC) on soil physical properties and black oat (Avena strigosa Schreb) growth. For this purpose, four soils were collected: Latossolo Vermelho distrófico retrático (Ferralsol LVCN), Cambissolo Húmico alumínico típico (Cambisol CHLG), Nitossolo Bruno distrófico típico (Nitisol NBPA), and Nitossolo Bruno distrófico húmico (Nitisol NBSJ). They were submitted to five degrees of compaction (bulk densities corresponding to 80, 85, 90, 95, and 100 % DC), defined by their relation to the maximum density obtained by the Normal Proctor Test. For each DC, porosity, soil water retention curve, penetration resistance, hydraulic conductivity, and aeration capacity were determined. In a greenhouse, the oats were cultivated in the four soils with five different degrees of compaction. The experiment was carried out in a completely randomized design, factorial scheme, and five replications. Crop measurements included the growth rate, shoot dry matter, and forage quality analysis. Soil compaction changed the physical properties of soils. In all tested soils, macroporosity and total porosity decreased, more intensely at LVCN. It had macroporosity below the critical level (0.10 m3 m-3) from DC 85. Hydraulic conductivity also decreased in all soils, which is evidence of significant environmental degradation from DC 90 onwards. Microporosity increased in the four soils due to compaction effect, and it is one of the reasons why permanent wilting point has increased. It resulted in a problem at NBSJ, mainly because it reduced the available water volume at DC 90, 95, and 100. Penetration resistance has also increased from DC 80 to 100 at all soils, exceeding the limit of 2 MPa in DC 80 for NBSJ, DC 85 for NBPA and LVCN, and DC 95 for CHLG, representing a risk to root development. Regarding black oat crop, there was a reduction in shoot dry matter only in Cambisol and in the higher DC, fiber content keeps within a satisfactory amount, without affecting forage quality in all soils and DC, thus showing that black oat is tolerant to compaction.

Resumo As videiras podem ser cultivadas em diferentes solos e condições climáticas. Entretanto, o efeito destas variáveis na videira e na composição das uvas é complexo. O objetivo deste estudo foi avaliar o efeito das classes de solo e as condições meteorológicas nas características produtivas e na composição da uva Cabernet Sauvignon. O experimento foi implantado no município de São Joaquim, no Planalto Sul Catarinense. A cultivar foi da variedade Cabernet Sauvignon, cultivada em três solos (Cambissolo Háplico, Cambissolo Húmico e Nitossolo Bruno) e analisada por duas safras (2015 e 2016). As condições meteorológicas avaliadas foram a precipitação pluviométrica, a insolação e as temperaturas média, máxima e mínima. Nos solos, foram determinados os atributos físicos e químicos, e na videira, as características produtivas, físico-químicas e compostos fenólicos das uvas. Tanto a classe de solo como as safras tiveram efeito significativo nas características produtivas, físico-químicas e nos compostos fenólicos da uva. O solo foi mais importante para as características produtivas e compostos fenólicos, enquanto as condições meteorológicas foram mais importantes para as características físico-químicas da uva. As características produtivas e a composição da uva foram mais adequadas à produção de vinho na safra de 2016 e nas classes Nitossolo Bruno e Cambissolo Háplico.

Abstract Grapevines can be grown in different soil classes and climatic conditions. However, the effect of these variables on grapevine and grape composition is complex. The aim of this study was to evaluate the effect of soil classes and climatic conditions on productive and physico-chemical characteristics and phenolic compounds of Cabernet Sauvignon grapes. The experiment was carried out in São Joaquim (SC), located on the Southern Plateau of Santa Catarina. Cabernet Sauvignon variety was analyzed in three soils (Dystrudepts, Humudepts and Rhodudalfs) and two harvests (2015 and 2016). The climatic variables analyzed were rainfall, insolation and average, maximum and minimum temperatures. Soil physical-chemical attributes, productive and physico-chemical characteristics and phenolic compounds of grapes were analyzed. Both soil class and harvests had significant effect on productive and physico-chemical characteristics and phenolic compounds of grapes. Soil was more important for productive characteristics and phenolic compounds, while meteorological conditions were more important for the physico-chemical characteristics of grapes. Productive characteristics and grape composition were more adequate to wine production in the 2016 harvest and in Rhodudalfs and Dystrudepts soil classes.