Resumo em Inglês:

Abstract Surface runoff in agricultural areas promotes the transport of biological structures, such as arbuscular mycorrhizal fungi (AMF) spores, along with mineral particles, nutrients, and organic matter. Limited information exists regarding the relationships between the erosive process and the loss of AMF spores at the hillslope scale, as well as the effect of terracing on these relationships. The objective of this study was to quantify the loss of AMF spores in surface runoff water from agricultural soil managed under no-till and terraced conditions. The research was conducted in the Ribeirão Vermelho watershed, in a hillslope area in Cambé, Paraná, Brazil. Two experimental plots measuring 2.5 hectares each were installed, with one managed without terraces (NTP) and the other with level terraces (TP). At the lower end of the plots, a runoff flow measurement structure (H-channel) was installed to determine the flow rate and suspended spore count. The runoff duration, peak flow rate, and spore count were determined during the period from October 2019 to October 2022. The terrace reduced over 35% of suspended spore loss, and the hysteresis pattern showed a counterclockwise loop in NTP and a clockwise loop in TP for events with higher peak flow rates. The hysteresis pattern indicated rapid spore mobilization and transport in TP, suggesting that spores originated from more distant sources or required more energy for transportation in NTP. Overall, there is evidence that the terrace influences spore variability on the hillslope, reinforcing the need for terracing in agricultural hillslope areas.

Resumo em Inglês:

Abstract No-tillage (NT) is a conservation practice adopted by 60% of the Brazilian farmers. Due to unsuitable management, compaction problem reported in soils under NT has increased. The study aimed to evaluate the influence of different soil tillage and different winter cover crops in long-term on crops biomass and maize yield and on soil penetration resistance (PR), in two crop seasons. The long-term experiment is located at the UTFPR Dois Vizinhos experimental station, with a combination of five soil tillage: NT; NT chiseled up to 0.35 m deep (Jumbo), annually (NTCa) and triennially (NTCt); NT with minimum tillage chiseled up to 0.35 m deep (Terrus), annually (NTMTa) and triennially (NTMTt); and four winter cover crops: black oats, common vetch, forage radish, and a mixture of oats + vetch + radish (mix). Dry matter production of cover crops was higher in oats and the mix, and in NTMTa in both years (2021 and 2022). Soil chiseling reduces PR, however over time, an increase was observed. NT showed higher PR, especially in the 0.15-0.20 m soil layer, but it did not impact crop production. Maize yield was not influenced by cover crops or soil tillage. NT proved to be the most efficient soil management, as its performance in maize yield was similar to the others, indicating the way forward in the pursuit of a more sustainable agriculture.

Resumo em Inglês:

Abstract Root growth is crucial in crop production and is influenced by soil attributes, but also affects soil chemical, physical and biological quality, along with management and conservation practices. In this paper, soybean root growth data from a field study at Guarapuava, Paraná State, Brazil are examined. In 2019, at a farm with over 35 years of no-tillage system (NT) adoption, three management sets were established in 1,1 ha macroplots: 1) farmer's NT standard (FNT), without terraces, with downhill farming and with autumn fallow; 2) autumn cover crops and contour farming added to FNT, as best management practices (BMP); 3) terraces and contour farming (TC) added to FNT. Soybean was sowed in November 2020 and 2021, and minirhizotron tubes (1 m long, 7 cm wide) were installed into the soil just after soybean emerged in 2020. Root length, area, volume, and diameter were evaluated with the help of a root scanner. Data were submitted to descriptive statistics. The added conservation practices improved root length, area and volume, significantly for BMP in the subsoil (40-60 cm) compared to FNT standard. Minirhizotron enabled the study of roots in the field, but data variability was high, so that for annual crops with pivoting roots like soybean, root observation points (6 per plot) must be increased, and crop stand close to the observation points is a critical font of error.

Resumo em Inglês:

Abstract Soil health has been used worldwide for soil monitoring in different soil use and management. The objective of the study was to evaluate, in a Subtropical Oxisol of the Campos Gerais region in Paraná state, if the Visual Evaluation of Soil structure (VESS) and Soil Management Assessment Framework (SMAF) approaches allow evaluate soil response to various land uses or soil tillage used in the region. The land use and tillage practices consist of conventional tillage, minimum tillage, no-tillage, and secondary forest. The SMAF was used as a tool to evaluate the soil health using five indicators: pH, phosphorus, potassium, bulk density, and soil organic carbon. The VESS was used to determine the soil structural quality. The secondary forest showed the best soil structure and tillage practices declined soil structure quality. Similarly, the soil health index was higher in secondary forest compared to tillage practices, and the tillage had little effect on soil health. The SMAF showed differences between land use and tillage practices. The VESS method could be used as a complementary tool for monitoring the soil health.

Resumo em Inglês:

Abstract This study aims to show the efficacy of the pedagogy of alternation in soil practices. A compilation of 1200 alternation notebooks of students from 2022 to 2023 was analyzed. The documentary analysis was based on the qualitative meta-synthesis. It was observed that the vast majority of techniques reported in the notebooks matched the reality of the students' properties. The pedagogy of alternation involving soil management and conservation practices has a positive environmental impact on students' rural properties, which supports the practice of sustainable management, contributing to pedagogical instrument development and in the teaching-learning process. Labor is related to social movements and the education of students. Within this framework, it is important to state that this pedagogical system allows students to be free, autonomous, and emancipated in the relationship between agricultural labor and school education.

Resumo em Inglês:

Abstract The terracing is important for erosion processes control in agricultural areas. However, agricultural terraces are being removed from the production areas under no-tillage systems. There are still uncertainties about the terracing effects on the soil saturated hydraulic conductivity (Ks) and macroporosity (Macro), which represent the functionality of the system. We aimed to evaluate the magnitude and spatial distribution of Ks and Macro and the correlation between these soil properties in two paired megaplots, of 1.923 ha, one with terraces (T) and another without terraces (WT). Ks and Macro were determined at 0.00-0.10 m, 0.10-0.20 m, 0.20-0.30 m, and 0.30-0.40 m soil layers and submitted to descriptive statistical, geostatistics, and Spearman correlation analysis. Ks was highest in the 0.00-0.20 m and lowest in the 0.20-0.40 m layers in T. In WT, Ks was highest in the 0.00-0.10 m and lowest in the 0.10-0.40 m layers. However, the Macro was highest in the 0.00-0.10 m and lowest in the 0.10-0.40 m layers in both megaplots. Ks and Macro had a positive correlation in both megaplots. The spatial distribution of Ks and Macro had a positive correlation, with regions with higher Ks coinciding with regions with higher Macro in both megaplots. The spatial distribution of Ks and Macro in WT did not have a clear trend, while in T there was a slight stratification in strips interspersed with higher and lower Ks and Macro. These initial trends are not conclusive considering the short term between terraces removal and Ks and Macro evaluation.

Resumo em Inglês:

Abstract in Brazil, the development of a strong technical foundation for soil and water conservation has made no-tillage (NT) the leading method for preparing land for temporary crops. Despite this, there's insufficient information regarding the extent to which farmers have adopted NT and conservation agriculture (CA) and the distribution and evolution of these practices within Paraná-a state at the forefront of NT and CA implementation. This study investigates the adoption rates of NT and CA among Paraná's farmers, focusing on temporary crops. It utilizes specialized data from the Brazilian Institute of Geography and Statistics' agricultural censuses of 2006 and 2017. Adoption rates for NT and CA were determined by comparing their proportions in both the number of farming properties and the overall land area devoted to temporary crops across various microregions. Findings indicate a rise in the adoption of NT from 68.5% to 78.9% and CA from 14.6% to 27.7% over the 2006 to 2017 period. Moreover, adoption rates varied across the 39 microregions, with the highest rates in regions dominated by temporary crops, particularly soybeans, maize, and wheat. Conversely, the lowest adoption rates were found in microregions where permanent crops and pastures prevailed, and sugarcane, cassava, and rice were the primary temporary crops.

Resumo em Inglês:

Abstract Conservation soil management systems can promote beneficial changes in the edaphic fauna, which is important in improving and maintaining soil quality. Hence, this study aimed to evaluate the edaphic fauna in two areas with soils managed under no-till with and without terraces for four years. The edaphic fauna was evaluated by installing 32 pitfall trapsin each experimental plot. After seven days, the traps were removed, and the sampled individuals were classified at the level of major taxonomic groups. Collembola, Acari, Formicidae, Coleoptera, and Araneae were the most abundant in both study areas. The mean abundance of the order Coleoptera stood out in the no-till system with terraces in 2021, while the orders Collembola and Acari were more abundant without terraces in 2019 and 2021, and 2021 and 2022, respectively. There was a greater abundance of organisms for both areas in 2021, with significant equitability in the no-till system with terraces. Thus, the results showed that only some groups are positively affected by mechanical erosion control.

Resumo em Inglês:

Abstract The use of conservation practices for sustainable agriculture production has grown in the last decades, mainly due to the no-tillage and the cover crops. The aim was to evaluate the productive performance of phytomass in three crop years with the effect of different winter cover crops and nitrogen (N) rates in succession maize. The study was carried out at the Federal Technological University of Paraná, in Dois Vizinhos, between 2020 and 2023, in a long-term experiment (2010). The treatments were a combination of three N rates applied to maize and eight winter cover crops. The annual cropping systems were buckwheat-winter cover crops-maize. The dry phytomass of buckwheat showed a significant difference between the residual N rates, but no difference to the cover crops. For the winter cover crops, mix and single oats showed a higher phytomass production, especially oats+vetch+radish, while common vetch had a lower production. Phytomass of maize was responsive to N addition, regardless of crop year; however, in a dry weather year, the cover crops showed no difference. Cumulative annual phytomass ranged from 10 to 28.6 Mg ha¯1 and was related to the N rate and the winter crop. Maize grain yield was higher after vetch and lupine and with N fertilization. Therefore, winter cover crops and N fertilization can contribute to the productive development of all the crops in the cropping system.

Resumo em Inglês:

Abstract Phytoliths are plant micro-remains found in soils and sediments. Their durability, abundance and diagnostic morphologies make them reliable environmental proxies, especially when associated with other biological, chemical, or physical indicators. However, in some cases, phytoliths are the only biological proxy available on the soil for paleoenvironmental studies, therefore, it requires extra attention to taphonomic processes affecting these silica bodies’ assemblage. The preservation and conservation of this markers in the soil is directly linked to the edaphic conditions to which it is subjected over time. Hence, the application of this proxy requires care in order to avoid misinterpretations, since phytoliths are subject to degradation and movement within the soil due to soil-plant-water interactions, soil hydrological processes a/nd bioturbation. In this article we examine the diversity and taphonomic evidence found in an Oxisol’s phytolith assemblage in search to better our understanding of this silica bodies preservation in tropical soils. The result shows that the assembly found is very resistant to tropical edaphic conditions, displaying taphonomic signs such as breakage and corrosion across the profile, with significant increase with depth, pointing to the phytolith’s early deposition. Also, results suggest that Grass Silica Short Cell Phytolith tend to present more breakage than corrosion due to its smaller size when compared to bigger morphotypes, which have corrosion features more often.