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Onshore oil well drill cuttings and sunflower cake from biodiesel production require an appropriate destination to reduce the risks of environmental contamination. The aim of this study was to evaluate the potential use of the combination of different doses of these wastes on the growth of sunflower plants (Helianthus annus L.) and on soil chemical attributes after cultivation, making it possible to recommend safe application doses. Sunflower plants, cultivar Neon, were cultivated in a greenhouse for 80 days in Planossolo Háplico (Ultisol) as the main substrate. The design used was completely randomized, in a 6 × 6 factorial arrangement, composed of five doses of sunflower cake (2, 4, 8, 16 and 32 Mg ha-1) and five doses of drill cuttings (5, 15, 30, 45 and 60 Mg ha-1) and an experimental control using only Ultisol After cultivation, soil chemical attributes and the parameters height (H), stem diameter (D), and dry mass (DMAP) and nutrient contents in the aerial part of the plants were analyzed. Sunflower cake dose of 32 Mg ha-1 limited the germination of sunflower plants. In sunflower plants, the highest contents of calcium (Ca), magnesium (Mg), phosphorus (P) and potassium (K) were verified when the sunflower cake doses were associated with drill cuttings doses >45 Mg ha-1. The mixture between sunflower cake and drill cuttings in the proportion of 16:45 Mg ha-1, respectively, promoted higher H, D and DMAP of sunflower plants, as well as a considerable improvement in soil fertility, without causing significant increments in sodium content in the soil after cultivation.HighlightsInadequate disposal of agro-industrial wastes represents loss of raw material and energy.Drill cuttings and sunflower cake wastes enable improvements in soil fertility attributes.The combination of sunflower cake and drill cuttings contributed to sunflower growth and nutrient contents.The mixture of drill cuttings and sunflower cake has potential for use as agricultural input.

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Increasing the diversity of plant species in agricultural production areas favors the maintenance or improvement of soil quality, particularly for soils with a sandy texture. This beneficial effect is related to the formation of aggregates of different origins. This study aimed to (i) verify whether soil use and management affect the proportion of biogenic (Bio) and physicogenic (Phy) aggregates and (ii) verify whether biogenic aggregation is more likely to lead to soil improvement than physicogenic aggregation. Three management systems were evaluated (permanent pasture, PP; no-tillage system, NT; and no-tillage + Brachiaria system, NT + B) as well as a reference area (Atlantic Forest biome vegetation, NF). According to their origin or formation pathway, the aggregates were separated, identified, and classified as Bio (formed by biological processes) and Phy (resulting from chemical and physical actions). The differentiation between Bio and Phy aggregates was performed based on the visualization of morphological features, such as shape, size, presence of roots, porosity, and subunit arrangements, and junctions. Only the PP area was able to promote greater aggregate formation of biological origin, with greater amounts of Bio aggregates. The highest total organic carbon (TOC) contents and the least negative δ13C values were also quantified in the aggregates of the PP area. The NT + B system provided an increase in the TOC content of its aggregates in comparison with aggregates in the NT and NF areas. Among the formation pathways, the Bio aggregates had the highest TOC and soil organic matter fractions contents and the most negative δ13C values. Perennial forage grasses vegetation was more important than the plant species diversity in favoring Bio aggregate formation. The beneficial effect of Brachiaria can be observed when incorporated as part of intercropping with corn in grain production systems. The biogenic aggregates favored the concentration of more labile soil organic matter fractions. The results of this study can provide important theoretical information for future studies focused on the combination of different plant species in agricultural food production areas on sandy-textured soils.

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Fruticulture in the Amazonian Rainforest is one of the main causes of deforestation, biodiversity loss, and soil erosion. Fruticulture plays a key role in the soil traits and soil organic matter (SOM) compartments by altering the soil ecosystem. Our aim was to assess the influence of Forest-Fruticulture conversion on soil traits, and SOM fractions in Brazil's Legal Amazon. The experiment was carried out in field conditions using four land uses as main treatments: Bixa orellana, Theobroma grandiflorum, Paullinia cupana, and the Amazon Rainforest. The soil physicochemical traits were analyzed using samples that were collected from 0-5, 5-10, and 10-20 cm soil depth by using grids (10 × 10 m) with 36 sampling points. Our results showed that the Fruticulture promoted an increase in bulk density, GMD, aggregate diameter, soil porosity, gravimetric moisture, sand, clay, carbon associated with humic acid, and, the sum of bases (K+, Ca2+, and Mg2+), while the Amazon Rainforest showed the highest values of silt, soil P content, SOC, p-SOC, m-SOC, carbon associated with fulvic acid, humine, and soil C stock. Overall, the fruticulture farming systems have negative effects on SOM compartments. The results of our study highlight the importance of considering fruticulture with endemic plant species by promoting soil fertility and soil aggregation.

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The structure of humic substances (HSs) and the humification process are critical topics for understanding the dynamics of carbon on the planet. This study aimed to assess the structural patterns of 80 humic acid (HA) samples isolated from different soils, namely, Histosols, Ferralsols, Cambisols, Mollisols, Planosols and vermicompost, by spectroscopic characterization using solid-state 13C nuclear magnetic resonance cross-polarization/magic angle spinning combined with chemometric techniques. All 80 HAs had a similar structural pattern, regardless of their source of origin, but they had different relative quantities of organic C species. The different structural amounts of the various organic C fractions generated different properties in each of the HAs. This explains why there were similarities in the HS functions but why the intensities of these functions varied among the samples from the different soil types and environments, confirming that HSs are a group of compounds with a structural identity distinct from the molecules that give rise to them. There appears to be no single definition for the humification process; therefore, for the soils from each source of origin, a specific humification process occurs that depends on the characteristics of the local environment. Humification can be understood as a process that is similar to a chemical reaction, where the key factor that determines the formation of the products is the structural characteristics of the reactants (organic substrates deposited in the soil). The degree to which the reaction progresses is governed by the reaction conditions (chemical, physical, and biological properties of the soil). The structural patterns for HSs obtained in this study justify the existence of HSs structured as self-assembled, hydrophilic and hydrophobic domains that, under certain conditions, can undergo transformations, altering the balance of organic carbon in the environment.

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The productive potential of the rubber tree (Hevea brasiliensis) is dependent on its genetic composition, in addition to edaphoclimatic factors and management practices. However, as soil properties are not homogenous, knowing the spatial variability of soil attributes would be important to increase productivity and reduce production costs. In this context, the objective of this study was to determine the spatial variability of chemical attributes of the soil and its influence on the nutritional status and growth of rubber tree clones. Clones FX 3864, FDR 5788, CDC 312, and RRIM 600 were planted at Jaturnaíba Farm, in the municipality of Silva Jardim, Rio de Janeiro State, Brazil. The sampling sites were distributed at a spacing of 20 × 20 m on the northern and southern sides of the relief. The chemical attributes of the soil (pH, Ca2+, Mg2+, K+, P, Al3+, H+Al, sum of bases, cation exchange capacity, and base saturation) were evaluated at a depth of 0­20 cm in the different clone plantations. Additionally, the N, P, K, Ca, and Mg content as well as trunk circumference and total plant height, were also evaluated. Geostatistics was used to determine the spatial variability of the soil and clone attributes, while Ordinary Kriging was used to draw variability maps of the variables. A difference in the distribution of the variables, which was dependent on the slope of the relief, was detected through the maps. The southern side presented better conditions as some degradation was observed on the northern side. Certain soil characteristics influenced the distribution of the attributes of the planted clones; for example, the low concentration of Ca2+ in the soil caused Ca deficiency in the FX clone on the southern slope, indicating that liming did not supply enough nutrients for this clone. Our results showed that the variability in soil attributes influenced the nutritional status and growth of the rubber tree clones, indicating that variability maps can guide the planting and management of the rubber tree, providing more efficient management.

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Reducing soil degradation and its impacts on the environment have been one of the main challenges of the 21st century, exacerbated by a direct link between increases in the human population and soil degradation that raises current and future food security concerns. Despite this, experiences worldwide reveal that degraded land restoration projects have either achieved little success or failed. Thus, understanding the underlying causes and devising appropriate restoration mechanisms is crucial. Soil amelioration using beneficial microorganisms, particularly arbuscular mycorrhizal fungi (AMF), is essential and pragmatic. Glomalin, a type of glycoprotein produced by arbuscular mycorrhizal fungi in the phylum Glomeromycota, contributes to the mitigation of soil degradation. Moreover, AMF and glomalin are highly correlated with other soil physico-chemical parameters and are sensitive to changes in the environment. As a result of this, they have been recommended for monitoring the recovery of degraded soil or stages of soil degradation. In this review, we discuss the role of AMF and glomalin in the restoration of degraded soils, including improvements to the soil structure and soil organic matter (SOM), microbial activity, reduction of fertility loss, bioremediation, and mitigation of the effects of drought and saline stress. We highlight the research gaps and discuss the prospects. This knowledge will improve our understanding of the ecological conduct of glomalin and AMF, stimulate future research, and be useful to sustainable restoration of degraded lands. Furthermore, we discussed the challenges and obstacles in the legislation and future perspectives on the production of inoculants based on AMF in Brazil.

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Forest canopies have an important influence on the global climate balance. Through the analysis of the temperature of the canopy, it is possible to infer about the physiological aspects of the plants, helping to understand the behavior of the vegetation and, consequently, in the environmental monitoring and management of green areas. This study aims to validate the MOD11A2 V006 product from canopy surface temperature data obtained by an infrared radiation sensor. For the validation of the MOD11A2 product, a comparative analysis was performed between the land surface temperature (LST) data, obtained by the MODIS sensor, and the canopy temperature data, obtained by the SI-111 infrared radiation sensor coupled to the Itatiaia National Park (PNI) micrometeorological tower. Meteorological variables and land surface temperature collected from January to December 2018 in the PNI were also analyzed. The results reveal that the MOD11A2 product overestimates the canopy temperature in the daytime (MB ranging from 1.56 to 3.57 °C) and underestimates in the night time (MB ranging from - 0.18 to - 4.22 °C). During daytime, the months corresponding to the dry season presented a very high correlation (r = 0.74 and 0.86) and the highest values for the Willmott index (d = 0.70 and 0.64). At nighttime, the MOD11A2 product did not present a good performance for the LST estimation, especially in the rainy season. Therefore, we observed that the MOD11A2 product has limitations to estimate the land surface temperature and that possible changes in the algorithm of this product can be performed for high atmospheric humidity conditions.

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This study assessed the effect of cover crop biomass on the epigeal fauna of an organic eggplant (Solanum melongena L.) cropping system. A randomized block design was used, with four cover crop treatments: brachiaria, crotalaria, millet, and cocktail (brachiaria, crotalaria and millet). The epigeal faunal indices were determined at each plot. The epigeal fauna of a secondary forest site was also assessed for comparison. Epigeal individuals were collected using pitfall traps at two sampling periods (110 and 180 days after mowing cover crops). Soil samples were collected for determination of physical and chemic properties. 2032 individuals were captured in the first sampling and 3806 individuals in the second. The highest values of wealth in the first collection were observed in the millet and cocktail areas. Cluster analysis showed similarity of epigeal faunal groups between millet and brachiaria plots at the first sampling and between cocktail and crotalaria sites at the second sampling. Co-inertia analysis showed a significant covariance between epigeal fauna at the second sampling and soil properties. The cover crops management had a beneficial influence on the activity, wealth and ecological indexes, in both sampling periods. The positive association observed between epigeal faunal groups and soil physical and chemical properties demonstrates the efficiency of cover crops in improving soil quality in organic cropping systems.(AU)

O objetivo deste estudo foi avaliar o efeito da fitomassa de diferentes plantas de cobertura no desenvolvimento da comunidade da fauna epígea em área de cultivo orgânico de berinjela (Solanum melongena, L.). Foi adotado delineamento em blocos ao acaso, com quatro tratamentos de plantas de cobertura: braquiária, crotalária, milheto e coquetel (crotalária, braquiária e milheto), além de uma área de floresta secundária (FR). A fauna epígea avaliada por meio de armadilhas do tipo "pitfall traps" em dois períodos de coletas, aos 110 dias e aos 180 dias, após o corte das plantas de coberturas. Foram coletadas amostras de solo para análise de atributos físicos e químicos. Foram capturados 2032 indivíduos na primeira coleta e 3806 indivíduos na segunda coleta. Os maiores valores de riqueza na primeira coleta foram observados nas áreas milheto e coquetel. A análise de agrupamento mostrou similaridade dos grupos da fauna epígea entre o milheto e braquiária na primeira amostragem e entre o coquetel e crotalária na segunda amostragem. A co-inércia evidenciou covariância significativa entre a fauna epígea da segunda coleta e os atributos do solo. O manejo com plantas de coberturas influenciou de forma benéfica a atividade, riqueza e índices ecológicos, em ambos os períodos de amostragens. A associação positiva entre grupos da fauna e os atributos físicos e químicos mostram a eficiência das plantas de coberturas em cultivo orgânico na promoção de melhorias da qualidade do solo.(AU)

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This study assessed the effect of cover crop biomass on the epigeal fauna of an organic eggplant (Solanum melongena L.) cropping system. A randomized block design was used, with four cover crop treatments: brachiaria, crotalaria, millet, and cocktail (brachiaria, crotalaria and millet). The epigeal faunal indices were determined at each plot. The epigeal fauna of a secondary forest site was also assessed for comparison. Epigeal individuals were collected using pitfall traps at two sampling periods (110 and 180 days after mowing cover crops). Soil samples were collected for determination of physical and chemic properties. 2032 individuals were captured in the first sampling and 3806 individuals in the second. The highest values of wealth in the first collection were observed in the millet and cocktail areas. Cluster analysis showed similarity of epigeal faunal groups between millet and brachiaria plots at the first sampling and between cocktail and crotalaria sites at the second sampling. Co-inertia analysis showed a significant covariance between epigeal fauna at the second sampling and soil properties. The cover crops management had a beneficial influence on the activity, wealth and ecological indexes, in both sampling periods. The positive association observed between epigeal faunal groups and soil physical and chemical properties demonstrates the efficiency of cover crops in improving soil quality in organic cropping systems.

O objetivo deste estudo foi avaliar o efeito da fitomassa de diferentes plantas de cobertura no desenvolvimento da comunidade da fauna epígea em área de cultivo orgânico de berinjela (Solanum melongena, L.). Foi adotado delineamento em blocos ao acaso, com quatro tratamentos de plantas de cobertura: braquiária, crotalária, milheto e coquetel (crotalária, braquiária e milheto), além de uma área de floresta secundária (FR). A fauna epígea avaliada por meio de armadilhas do tipo "pitfall traps" em dois períodos de coletas, aos 110 dias e aos 180 dias, após o corte das plantas de coberturas. Foram coletadas amostras de solo para análise de atributos físicos e químicos. Foram capturados 2032 indivíduos na primeira coleta e 3806 indivíduos na segunda coleta. Os maiores valores de riqueza na primeira coleta foram observados nas áreas milheto e coquetel. A análise de agrupamento mostrou similaridade dos grupos da fauna epígea entre o milheto e braquiária na primeira amostragem e entre o coquetel e crotalária na segunda amostragem. A co-inércia evidenciou covariância significativa entre a fauna epígea da segunda coleta e os atributos do solo. O manejo com plantas de coberturas influenciou de forma benéfica a atividade, riqueza e índices ecológicos, em ambos os períodos de amostragens. A associação positiva entre grupos da fauna e os atributos físicos e químicos mostram a eficiência das plantas de coberturas em cultivo orgânico na promoção de melhorias da qualidade do solo.

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ABSTRACT: This study assessed the effect of cover crop biomass on the epigeal fauna of an organic eggplant (Solanum melongena L.) cropping system. A randomized block design was used, with four cover crop treatments: brachiaria, crotalaria, millet, and cocktail (brachiaria, crotalaria and millet). The epigeal faunal indices were determined at each plot. The epigeal fauna of a secondary forest site was also assessed for comparison. Epigeal individuals were collected using pitfall traps at two sampling periods (110 and 180 days after mowing cover crops). Soil samples were collected for determination of physical and chemic properties. 2032 individuals were captured in the first sampling and 3806 individuals in the second. The highest values of wealth in the first collection were observed in the millet and cocktail areas. Cluster analysis showed similarity of epigeal faunal groups between millet and brachiaria plots at the first sampling and between cocktail and crotalaria sites at the second sampling. Co-inertia analysis showed a significant covariance between epigeal fauna at the second sampling and soil properties. The cover crops management had a beneficial influence on the activity, wealth and ecological indexes, in both sampling periods. The positive association observed between epigeal faunal groups and soil physical and chemical properties demonstrates the efficiency of cover crops in improving soil quality in organic cropping systems.

RESUMO: O objetivo deste estudo foi avaliar o efeito da fitomassa de diferentes plantas de cobertura no desenvolvimento da comunidade da fauna epígea em área de cultivo orgânico de berinjela (Solanum melongena, L.). Foi adotado delineamento em blocos ao acaso, com quatro tratamentos de plantas de cobertura: braquiária, crotalária, milheto e coquetel (crotalária, braquiária e milheto), além de uma área de floresta secundária (FR). A fauna epígea avaliada por meio de armadilhas do tipo "pitfall traps" em dois períodos de coletas, aos 110 dias e aos 180 dias, após o corte das plantas de coberturas. Foram coletadas amostras de solo para análise de atributos físicos e químicos. Foram capturados 2032 indivíduos na primeira coleta e 3806 indivíduos na segunda coleta. Os maiores valores de riqueza na primeira coleta foram observados nas áreas milheto e coquetel. A análise de agrupamento mostrou similaridade dos grupos da fauna epígea entre o milheto e braquiária na primeira amostragem e entre o coquetel e crotalária na segunda amostragem. A co-inércia evidenciou covariância significativa entre a fauna epígea da segunda coleta e os atributos do solo. O manejo com plantas de coberturas influenciou de forma benéfica a atividade, riqueza e índices ecológicos, em ambos os períodos de amostragens. A associação positiva entre grupos da fauna e os atributos físicos e químicos mostram a eficiência das plantas de coberturas em cultivo orgânico na promoção de melhorias da qualidade do solo.

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Sugarcane burning has been widely practiced in Brazil and worldwide. In the long term, this farming practice can cause soil erosion, reduction in organic carbon (OC) and consequently, changes in the structure of soil organic matter (SOM). Such changes may be difficult to reverse. This study aimed to assess the medium- and long-term effects of sugarcane burning on SOM characteristics, both in terms of quantity and structural quality and evaluate the application of vinasse as a strategy to attenuate fire-induced changes in burned soil. The experiment was conducted in a 50-year-old sugarcane field on soils classed as Cambissolo Háplico (Inceptisol). Four plots were sampled: a) burning of sugarcane for harvest for 37 years (SCB37); b) renewal of the sugarcane field and burning for harvest for 3 years (SCB3); c) renewal of the sugarcane field without burning for harvest for 3 years (SCWB), and d) renewal of the sugarcane field and burning for harvest with the application of vinasse for 3 years (SCV). Chemical and physical characterization of SOM was performed by solid-state spectroscopy (UV-vis, ATR-FTIR e 13C NMR CP/MAS) and chemometric techniques. The results showed that sugarcane burning drastically impacts SOM content and its chemical structure, however, the application of vinasse preserves and restores the soil from the fire effects. Content of soil OC, particulate OC, mineral-associated OC, humic acid, humin and light fraction OM that were affected by fire, had an increase and recovery of contents by the vinasse application. Solid state spectroscopy showed that labile structures were lost in humic acids (HA) by fire and recalcitrant structures were preserved. The application of vinasse incorporated fragments of lipids and carbohydrates in HA structure. Burning sugar cane straw affects the integrity of soil organic matter but can be restored by applying vinasse.

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Agro-Forestry Systems (AFS), in addition to being a means of providing income, can be considered an alternative way of helping conserve biodiversity, both above and below ground. The aim of this study was to evaluate the accumulation of tree leaf litter and its nutrient content as well as the composition of fauna in the soil-litter layer in two Agro-Forestry Systems (AFS-1 and AFS-2), using as reference an area of secondary Forest (SF), in the Quilombola do Campinho da Independência community, Paraty, in the state of Rio de Janeiro (RJ), Brazil. The collection of accumulated leaf litter and soil-litter fauna was carried out from four sample points in each area and at two different seasons of the year, the rainy and the dry season. The leaf litter stock and its nutrient content (Ca, Mg, P, K and N) were measured. The extraction of fauna was carried out according to Tüllgren's method, modifying the Berlese funnel. The stock of accumulated leaf litter differed between the two areas only in the rainy season; the amounts were smaller in AFS-2. In general, the Agro-Forestry Systems were very similar to the secondary forest in terms of levels and/or stock of nutrients in the majority of cases, at least in one of the seasons studied. The composition of the soil fauna groups in the Agro-Forestry System (AFS-1 and AFS-2) had a high degree of similarity to that found in the forest, and these systems mainly favour the populations of groups like Collembola and Formicidae.

Os sistemas agroflorestais (SAFs) além de proporcionarem geração de renda, podem ser considerados como uma alternativa para conservação da biodiversidade, tanto acima quanto abaixo da superfície do solo. O objetivo desse estudo foi avaliar o estoque de serapilheira acumulada e seus estoques de nutrientes, bem como, a composição da fauna do conjunto solo-serapilheira, em dois sistemas agroflorestais (SAF-1 e SAF-2), utilizando como referência uma área de floresta secundária (FS), na comunidade Quilombola do Campinho da Independência, Paraty - RJ. A coleta da serapilheira acumulada e da fauna do sistema solo-serapilheira foi realizada a partir de quatro pontos amostrais em cada área, em duas épocas do ano, seca e chuvosa. Foi quantificado o estoque de serapilheira foliar, e seus estoques e teores de nutrientes (Ca, Mg, P, K e N). A extração da fauna foi realizada a partir do método modificado de Tüllgren, baseado no funil de Berlese. O estoque de serapilheira foliar acumulada só variou entre as áreas na estação chuvosa, sendo os menores valores quantificados no SAF-2. De maneira geral, os sistemas agroflorestais apresentaram semelhanças em comparação com a floresta para a maioria dos teores e/ou estoques de nutrientes, em pelo menos uma das épocas de avaliação. A composição dos grupos da fauna do solo dos sistemas agroflorestais (SAF-1 e SAF-2) apresentou um elevado grau de similaridade com a floresta, e estes sistemas favoreceram principalmente as populações de grupos como os Collembola e Formicidae.

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Several environmental impacts are resulting from the process of anthropization and climate variability that have caused degradation of biomes and humid environments. Thus, the objective of this study was to evaluate the effect of the anthropic process and the variation of climatic conditions on the dynamics of the marsh vegetation in the Pandeiros River preservation area in the north of Minas Gerais, Brazil. The Enhanced Vegetation Index (EVI) of product MOD13Q1 and the gross primary productivity (GPP) of product MOD17A2 of the Moderate Resolution Imaging Spectroradiometer (MODIS) were used for the period from 2001 to 2017 were used in this process. Rain and air temperature data were obtained from the Conventional Weather Station of Januária-MG. The time series were submitted to the nonparametric statistical test of Mann-Kendall. The process of anthropization of the swamp area in the environmental protection area of the Pandeiros River/MG (EPA) showed a pattern of expansion of vegetation cover associated with the reduction of the water table, a phenomenon resulting from the silting process and reduction of the incidence of rain in this region, which contributes to the reduction of ecosystem services. Thus, understanding the influence of climatic variables on the dynamics of vegetation in humid environments, such as the EPA swamp area on the Pandeiros River, is essential for the preservation and recovery of these ecosystems and for the implementation of public policies for preservation and conservation.

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The objective of this study was to evaluate the influence of agroforestry systems of different ages (AFS1: one-year old; AFS5: five-years old) on the biological attributes of soil; the following systems were used for comparison: a slash-and-burn (SBF) farming area, Caatinga which has been undergoing regeneration for 6 years (CaR6), and native Caatinga (NCa) in Brazil. Enzyme activity, abundance and composition of arbuscular mycorrhizal fungi (AMF), and production of glomalin-related soil proteins (GRSP) were evaluated at soil depths of 0­0.05 m. AMF species composition in the AFS was more similar to that in the NCa than in the SBF and CaR6 systems. In the rainy season, sporulation was most abundant in the AFS-1, CaR6, and SBF systems, whereas GRSP concentrations were highest in the AFS5 during the dry season. Acid phosphatase and arylsulfatase enzyme activity was lower in the AFS1 soils than in the NCa and SBF soils (rainy period), and levels of ß-glucosidase and fluorescein diacetate hydrolysis in the AFS were equal to or higher than those in the NCa in the dry season but lower in the rainy season. AFS thus appear to promote the maintenance of soil biological quality, and may be more sustainable than SBF farming systems in the Brazilian Caatinga over the long term.

O objetivo do estudo foi avaliar a influência de sistemas agroflorestais (AFS1: um ano de idade; AFS5: cinco anos de idade), nos atributos biológicos do solo usando como referência, uma área de agricultura de corte e queima (SBF), Caatinga em regeneração há 6 anos (CaR6), e Caatinga nativa (NCa), in Brasil. A atividade enzimática, a abundância e composição dos fungos micorrízicos arbusculares (AMF), e a produção de proteína do solo relacionada à glomalina (GRSP) foram avaliados, na profundidade de 0-5 cm do solo. A composição das espécies de AMF nos AFS foi mais semelhante a observada na NCa, do que os sistemas SBF e CaR6. Na estação chuvosa, a esporulação foi mais abundante em AFS-1, CaR6 and SBF quando comparada as outras áreas, enquanto a GRSP apresentou maiores teores no AFS5 no período seco. AFS1 apresentou atividade da fosfatase ácida e arilsulfatase inferiores tanto a NCa quanto a SBF, no período chuvoso. No período seco, a atividade de ß-glicosidase e a hidrólise do diacetato de fluoresceína (FDA) na AFS foram iguais ou superiores a Nca, mas menor no período chuvoso. Verifica-se que os AFS são potenciais para a manutenção da qualidade biológica do solo, podendo, em longo prazo, serem mais sustentáveis que a SBF, em ambiente de Caatinga.

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The objective of this study was to evaluate the space-time dynamics of the soil use and occupation of the Rio Roncador river basin between 1985 and 2010. The scenes were classified by two methods (partially unsupervised - K-Means and supervised - Maximum likelihood), the Thematic Mapper sensor products on the LANDSAT 5 orbital platform were used for both images of a 25-year time series (1985 to 2000). In order to measure the accuracy of the field the computer application Google Earth was used, in which nine classes (urban area, agricultural area, pasture, exposed soil, native forest, secondary vegetation, mangrove, altitude field and water) were collected. A multiple linear regression was performed, correlating the Normalized Difference Vegetation Index - mean NDVI (dependent variable) with the independent climatic variables (global solar radiation - MJm-2day-1, average air temperature - °C, relative humidity -%, evapotranspiration - mm d-1, and rain - mm). According to the general classification by Kappa parameter of the images for 2005 and 2010, they were identified as very good (68% and 74%). These results confirm that the Roncador River Basin is undergoing transformation in its landscape, with an average reduction of -49% in native vegetation areas due to the increase in urban areas (25%) and agriculture (31%). The statistical analysis showed that rainfall and air temperature were the only variables that presented significant sigma (0.04) and (0.02). The obtained coefficient of determination indicated that 47% of the variations of the "vegetation index" are explained by the environmental variables.

O objetivo deste estudo foi de analisar espaço-temporalmente a dinâmica do uso e ocupação do solo da bacia hidrográfica do Rio Roncador, localizada no município de Magé no Estado do Rio de Janeiro, entre os anos de 1985 a 2010. As cenas foram classificadas por dois métodos (parcialmente nãosupervisionada ­ K-Means e supervisionada ­ Máxima Verossimilhança), para ambos foram utilizados os produtos abordo da plataforma orbital LANDSAT 5 do sensor Thematic Mapper, para as imagens de uma sérietemporal de 25 anos (1985 a 2000). Para a aferição como verdade de campo utilizou-se se o aplicativo computacional Google Earth, no qual foram coletadas nove classes (área urbana, área agrícola, pastagem, solo exposto, floresta nativa, vegetação secundária, manguezal, campo de altitude e água). Foi feita uma regressão linear múltipla, correlacionando o Índice de Vegetação da Diferença Normalizada - NDVI médio (variável dependente) com as variáveis climáticas independentes (radiação solar global - MJm-2dia-1, temperatura média do ar - °C, umidade relativa do ar - %, evapotranspiração ­ mm d-1, e chuva - mm). Segundo a classificação geral pelo parâmetro Kappa das imagens para os anos de 2005 e 2010 estas foram identificadas como muito bom (68% e 74%). Estes resultados comprovam que a Bacia Hidrográfica do Rio Roncador está passando por transformação em sua paisagem, com redução média de (-49%) das áreas de vegetação nativa por aumento de áreas como urbana (25%) e agricultura (31%). A análise estatística evidenciou que a variável climática chuva e temperatura do ar foram às únicas que apresentaram sigma significativo (0.04) e (0.02), a regressão múltipla com R2 de 0.47, que significa que 47% das variações do "índice de vegetação" são explicados pelas variáveis ambientais.

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RESUMO

Agriculture can considerably change the composition and richness of the edaphic macrofauna, affecting the ecological and biological functions exerted by the fauna. This study was carried out in commercial production systems in the municipality of Guaíra, state of Paraná, Brazil. The objective of this study was to evaluate the effect of no-tillage systems (NTS) and seasonality on the diversity, richness, and composition of the edaphic macrofauna. Three areas managed under NTS for different periods 7 years (NTS-7), 14 years (NTS-14), and 23 years (NTS-23) under crop succession with soybean (summer) (aNTS7) and maize/wheat (winter) (NTS14 and NTS23) were evaluated, in addition to a native Atlantic Forest segment, which was used as a reference. Faunal samples were collected in the dry season (September 2013) and rainy season (February 2014). The edaphic macrofauna was evaluated using the method proposed by the Tropical Soil Biology and Fertility Program. Parametric statistics were applied, and the results were compared using Tukeys test at a level of significance of 5%. Species density and total richness were usually higher in the NTS14 and NTS23 in the dry season. However, higher indexes of equability were not detected because of the dominance of groups Formicidae and Isoptera. The areas with the highest equability were the reference area in the dry season and NTS23 in the rainy...(AU)

O uso agrícola pode alterar consideravelmente a composição e riqueza da fauna edáfica, influenciando nas funções ecológicas e biológicas desenvolvidas por estes organismos. O estudo foi realizado em sistemas agrícolas explorados comercialmente, no município de Guaíra - PR. O objetivo foi avaliar o efeito do tempo de implantação do SPD e da sazonalidade na diversidade, riqueza e composição da macrofauna edáfica. Foram avaliadas três áreas com diferentes tempos de adoção de plantio direto (PD), por 7, 14 e 23 anos, sob sucessão das culturas soja (verão) e milho/trigo (inverno) (PD7, PD14 e PD23 respectivamente), além de área de Floresta Atlântica como referência. As amostras de fauna foram coletadas nas épocas seca (setembro/2013) e chuvosa (fevereiro/2014). Para avaliação da macrofauna edáfica foi utilizado o método recomendado pelo Programa Tropical Soil Biology and Fertility. Foi aplicada estatística paramétrica e os resultados foram comparados pelo teste de Tukey, a 5% de probabilidade. De maneira geral, a maior densidade e riqueza total de indivíduos da macrofauna foram encontradas nas áreas PD14 e PD23 na época seca. Porém, maiores índices de equabilidade não foram observados devido à dominância dos grupos Formicidae e Isoptera. As áreas com maiores valores de equabilidade foram a área de referência na época seca e a área PD23 na época chuvosa, com valores de 0,87 e 0,61...(AU)

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RESUMO

Carbon (C) stabilization and the quality of soil organic matter (SOM) in a tropical climate are key aspects regulating carbon dioxide emissions and maintaining the C cycle. Soil management influences the accumulation of C, regulating the balance between mineralization and/or the humification of SOM. This study aimed to quantify inputs of different chemical forms of C into soil and to evaluate the structural chemical characteristics of humified SOM. Four management systems were established: Forest (F), Pasture (P), Conventional tillage (T), and No-tillage (NT). Total organic carbon (TOC) and nitrogen (TN) by depth, chemical forms of organic matter input, and spectroscopic characterization of SOM in the form of humic acids (HA) were analyzed. The results obtaining by PCA-13C NMR show that the forest accumulated a high amount of C on the surface (surpassing 20 Mg ha-1), favoring the formation of aliphatic HA (CAlkyl-H,R; CAlkyl-O,N; CAlkyl-O). In the NT management that increases biomass in the soil (14 Mg ha-1), the mineralization process occurred to a greater extent, allowing HA to form with a predominance of aromatic structures (CArm-H,R and CArm-O,N). The PCA-FTIR analysis showed that the P system contributed to the formation of similar HA to those under F management. The T management system incorporated the least TOC and TN, with different HA types being formed in these soils than what was found in other managements. Thus, minimally managed and more stabilized systems in tropical climates form HA of structural and compositional similarity, regardless of the nature of C (C3 or C4). In contrast, soils subjected to agricultural uses that promote higher or lower C inputs, form HA that are structurally different from P and F. This study demonstrates the need for developing experiments for model building to elucidate the relationships among C input, management type, and the formation of humic substances.

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Understanding the dynamics of the organic matter and nutrients in pig manure submitted to anaerobic digestion is important to assist in decision-making regarding the use of anaerobic biofertilizer in agriculture. Accordingly, this study was carried out with the objective of evaluating the changes in organic matter, quantified as the content of carbon in the humic and oxidizable fractions, and in the content of the organic and inorganic forms of phosphorus in the solid fraction of the manure, as a function of digestion time in anaerobic reactors. Evaluations were carried out after 7, 14, 21, 28, 35, 42, and 49 days of digestion, and the results were compared to the raw manure. Changes in organic matter occurred mostly in the labile fractions (fulvic acid and the F1 fraction), the content of which underwent a reduction, favoring the accumulation of more recalcitrant fractions in the final biofertilizer (humic acid and the F2, F3, and F4 fractions). Total P content did not change throughout the digestion process. However, the size of inorganic fraction of water-extractable P decreased by 16.7% after 49 days of digestion, as it was consumed by the decomposing microbiota to form stabilized organic matter, which accumulated along with the more recalcitrant fractions of P in the final biofertilizer. Therefore, the use of swine manure-derived anaerobic biofertilizer has less risk of environmental contamination with excessive P than the direct application of raw manure to the soil.(AU)

O entendimento da dinâmica da matéria orgânica e dos nutrientes no dejeto suíno submetido à biodegradação anaeróbia é importante por auxiliar nas tomadas de decisão para a utilização do biofertilizante anaeróbio como fertilizante agrícola. Nesse sentido, desenvolveu-se um estudo, utilizando reatores anaeróbios de bancada, com o objetivo de avaliar as mudanças na matéria orgânica, através da quantificação do carbono nas frações húmicas e oxidáveis, e nas formas orgânicas e inorgânicas de fósforo da fração sólida do dejeto suíno, em função do tempo de biodegradação. Realizaram-se avaliações nos seguintes tempos de retenção hidráulica: 7, 14, 21, 28, 35, 42 e 49 dias de biodegradação e os resultados comparados com o dejeto não degradado. As mudanças na matéria orgânica ocorreram em suas frações mais lábeis (C-ácido fúlvico e fração F1) com redução dos seus conteúdos, favorecendo o acúmulo de frações mais recalcitrantes no biofertilizante final (C-ácido húmico e frações F2, F3 e F4). O conteúdo total de P não sofreu mudanças ao longo do processo. No entanto, a fração inorgânica de P extraível em água reduziu em 16,7 % após 49 dias de biodegradação, sendo consumida pela microbiota decompositora para a formação de matéria orgânica estabilizada, que se acumula, juntamente com as frações mais recalcitrantes de P no biofertilizante final. O uso do biofertilizante anaeróbio suíno possui, portanto, menor risco de contaminação ambiental pelo excesso de P do que a aplicação direta do dejeto in natura no solo.(AU)

Assuntos

RESUMO

Agriculture can considerably change the composition and richness of the edaphic macrofauna, affecting the ecological and biological functions exerted by the fauna. This study was carried out in commercial production systems in the municipality of Guaíra, state of Paraná, Brazil. The objective of this study was to evaluate the effect of no-tillage systems (NTS) and seasonality on the diversity, richness, and composition of the edaphic macrofauna. Three areas managed under NTS for different periods 7 years (NTS-7), 14 years (NTS-14), and 23 years (NTS-23) under crop succession with soybean (summer) (aNTS7) and maize/wheat (winter) (NTS14 and NTS23) were evaluated, in addition to a native Atlantic Forest segment, which was used as a reference. Faunal samples were collected in the dry season (September 2013) and rainy season (February 2014). The edaphic macrofauna was evaluated using the method proposed by the Tropical Soil Biology and Fertility Program. Parametric statistics were applied, and the results were compared using Tukeys test at a level of significance of 5%. Species density and total richness were usually higher in the NTS14 and NTS23 in the dry season. However, higher indexes of equability were not detected because of the dominance of groups Formicidae and Isoptera. The areas with the highest equability were the reference area in the dry season and NTS23 in the rainy...

O uso agrícola pode alterar consideravelmente a composição e riqueza da fauna edáfica, influenciando nas funções ecológicas e biológicas desenvolvidas por estes organismos. O estudo foi realizado em sistemas agrícolas explorados comercialmente, no município de Guaíra - PR. O objetivo foi avaliar o efeito do tempo de implantação do SPD e da sazonalidade na diversidade, riqueza e composição da macrofauna edáfica. Foram avaliadas três áreas com diferentes tempos de adoção de plantio direto (PD), por 7, 14 e 23 anos, sob sucessão das culturas soja (verão) e milho/trigo (inverno) (PD7, PD14 e PD23 respectivamente), além de área de Floresta Atlântica como referência. As amostras de fauna foram coletadas nas épocas seca (setembro/2013) e chuvosa (fevereiro/2014). Para avaliação da macrofauna edáfica foi utilizado o método recomendado pelo Programa Tropical Soil Biology and Fertility. Foi aplicada estatística paramétrica e os resultados foram comparados pelo teste de Tukey, a 5% de probabilidade. De maneira geral, a maior densidade e riqueza total de indivíduos da macrofauna foram encontradas nas áreas PD14 e PD23 na época seca. Porém, maiores índices de equabilidade não foram observados devido à dominância dos grupos Formicidae e Isoptera. As áreas com maiores valores de equabilidade foram a área de referência na época seca e a área PD23 na época chuvosa, com valores de 0,87 e 0,61...

Assuntos

RESUMO

Understanding the dynamics of the organic matter and nutrients in pig manure submitted to anaerobic digestion is important to assist in decision-making regarding the use of anaerobic biofertilizer in agriculture. Accordingly, this study was carried out with the objective of evaluating the changes in organic matter, quantified as the content of carbon in the humic and oxidizable fractions, and in the content of the organic and inorganic forms of phosphorus in the solid fraction of the manure, as a function of digestion time in anaerobic reactors. Evaluations were carried out after 7, 14, 21, 28, 35, 42, and 49 days of digestion, and the results were compared to the raw manure. Changes in organic matter occurred mostly in the labile fractions (fulvic acid and the F1 fraction), the content of which underwent a reduction, favoring the accumulation of more recalcitrant fractions in the final biofertilizer (humic acid and the F2, F3, and F4 fractions). Total P content did not change throughout the digestion process. However, the size of inorganic fraction of water-extractable P decreased by 16.7% after 49 days of digestion, as it was consumed by the decomposing microbiota to form stabilized organic matter, which accumulated along with the more recalcitrant fractions of P in the final biofertilizer. Therefore, the use of swine manure-derived anaerobic biofertilizer has less risk of environmental contamination with excessive P than the direct application of raw manure to the soil.

O entendimento da dinâmica da matéria orgânica e dos nutrientes no dejeto suíno submetido à biodegradação anaeróbia é importante por auxiliar nas tomadas de decisão para a utilização do biofertilizante anaeróbio como fertilizante agrícola. Nesse sentido, desenvolveu-se um estudo, utilizando reatores anaeróbios de bancada, com o objetivo de avaliar as mudanças na matéria orgânica, através da quantificação do carbono nas frações húmicas e oxidáveis, e nas formas orgânicas e inorgânicas de fósforo da fração sólida do dejeto suíno, em função do tempo de biodegradação. Realizaram-se avaliações nos seguintes tempos de retenção hidráulica: 7, 14, 21, 28, 35, 42 e 49 dias de biodegradação e os resultados comparados com o dejeto não degradado. As mudanças na matéria orgânica ocorreram em suas frações mais lábeis (C-ácido fúlvico e fração F1) com redução dos seus conteúdos, favorecendo o acúmulo de frações mais recalcitrantes no biofertilizante final (C-ácido húmico e frações F2, F3 e F4). O conteúdo total de P não sofreu mudanças ao longo do processo. No entanto, a fração inorgânica de P extraível em água reduziu em 16,7 % após 49 dias de biodegradação, sendo consumida pela microbiota decompositora para a formação de matéria orgânica estabilizada, que se acumula, juntamente com as frações mais recalcitrantes de P no biofertilizante final. O uso do biofertilizante anaeróbio suíno possui, portanto, menor risco de contaminação ambiental pelo excesso de P do que a aplicação direta do dejeto in natura no solo.

Assuntos