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O Brasil mantém altas produções de diversas culturas, dentre elas o melão na região Nordeste que vem se destacando devido ao grande consumo de agrotóxicos, tornando-se um dos maiores consumidores, com o objetivo de assegurar as altas produções, o que justifica o valor gasto na compra dos produtos fitossanitários, movimentando o mercado brasileiro de defensivos agrícolas no ano de 2021, que foi em torno de R$ 768,4 bilhões. A utilização desses dos agrotóxicos de forma excessiva e o descarte incorreto de suas embalagens pós-uso tem promovido consequências danosas à saúde pública e prejuízos ao meio ambiente. Os comerciantes precisam orientar os agricultores sobre o tratamento e os tipos das embalagens para designar o descarte correto após o uso, como também indicar as centrais de recebimento, conforme indicado pelos comerciantes. Os fabricantes devem receber as embalagens e fazer a destinação de forma apropriada e os órgãos públicos devem fiscalizar o cumprimento da legislação vigente. No entanto, o objetivo do presente trabalho foi avaliar a gestão de descarte de embalagens vazias de agrotóxicos em áreas produtoras de melão. A presente pesquisa foi aplicada de forma descritiva, coletando dados e informações sobre a devolução de embalagens vazias do setor produtivo e a saída de embalagens (encaminhadas para reciclagem ou incineração) fornecidas pela Central de Recebimento de Embalagens Vazias de Agrotóxicos dos municípios produtores de melão no período de 2017 a 2019. A análise dos dados foi realizada no programa Microsoft® EXCEL® 2010. E a avaliação dos dados foram expressos em gráficos dos tipos Linha e Pizza. Ainda que a legislação seja muito bem elaborada, por trás, há uma estrutura de coleta das embalagens instrumentalizada pelo INPEV, o fato é que existe uma falta de estímulo, quer pela inexistência de incentivo nas informações divulgadas, quer pela falta rigorosa da fiscalização por parte do poder público, visto que a logística reversa não é realizada em todas as localidades da cadeia produtiva de melão e nem abrange toda a cadeia produtiva. O INPEV não conseguiu por seus postos de coleta itinerantes e nem atingiu a totalidade dos produtores rurais que detêm embalagens para devolução nos anos de 2017, 2018 e 2019. Entretanto, não havendo fiscalização, esses produtores ficam descompromissados e não se dispõem ao cumprimento da legislação. Acredita-se que a deficiência na Fiscalização, a desinformação a respeito da devolução de embalagens de agrotóxicos para a central de recebimento, proporciona o aumento de lixo tóxico e consequentemente influencia na contaminação do meio ambiente e no bem-estar da saúde populacional. No entanto, espera-se que mais atuação e ações do governo, junto com as instituições como inpEV, têm colaborado para colocar o Brasil na primeira posição em reutilização e destinação correta de embalagens vazias do tipo laváveis e não laváveis de agrotóxicos. Visto que com o aumento da conscientização no manejo dessas embalagens e a sua logística reversa, são imprescindíveis para a redução do impacto ambiental causado pelas atividades agrícolas no cultivo de melão.

O Bioma Caatinga está presente na região Nordeste brasileira, possuindo diversas espécies de plantas endêmicas como a Opuntia fícus-indical, Prosopis juliflora, Calotropis procera e Bromelia laciniosa, sendo a base alternativa da alimentação animal na Caatinga nos períodos de seca, onde a raça Boer vem assumindo importante papel no agronegócio na região Semiárida. Portanto, o objetivo da revisão foi analisar as espécies de plantas cultivadas na Caatinga para alimentação de caprino nos períodos de seca. Pelo fato da escassez da chuva nesse bioma se prolongar por vários meses durante o ano, houve a necessidade de adaptar as plantas que são ricas em proteínas brutas, altas concentrações de nutrientes e amido, que serve para fornecer alimentos dos caprinos, proporcionando aumento do peso e a produção de leite. Dessa forma, tem contribuído para adaptação da raça na Caatinga independente das condições ambientais e garante um excelente manejo alimentar alternativo em todas as épocas do ano.

A revolução tecnológica vem sendo acompanhada por alterações no estilo de vida, nos modos de produção e consumo da população, como decorrência direta desses processos vem ocorrendo um aumento na produção de resíduos sólidos, tanto em quantidade, quanto em diversidade, principalmente nos grandes centros urbanos. Atualmente passaram a abrigar em sua composição elementos sintéticos e perigosos aos ecossistemas e à saúde humana. Entretanto, as Cooperativas foram originadas pelas necessidades sociais e econômicas, com a finalidade de diminuir os resíduos sólidos urbano, auxiliando na questão ambiental, gerando trabalho e aumento de renda para a população. O objetivo do presente trabalho foi analisar a importância do trabalho das Cooperativas na reciclagem dos resíduos sólidos e a influência na conscientização da prática ambiental. Portanto, conscientizar e sensibilizar as pessoas são atitudes importantes quando se trata sobre às questões ambientais, envolvendo as Cooperativas de reciclagens como alternativa para a reduzir os impactos causados pelo lixo, podendo influenciar em uma sociedade mais justa, igualitária, apresentando maior consciência ambiental e comprometida com a sustentabilidade, protegendo o meio ambiente e garantindo a preservação dos ecossistemas para as futuras gerações.

The present work was aimed in order to evaluate the decomposition process of remaining straw from oat cultivars submitted to different handling during the cultivation of corn for silage intercropped with Urochloa brizantha cv. MG13 Braúna. We considered nine oat cultivars named as follows: "IAPAR 61 IBIPORÃ" oat hay (61F), "IAPAR 61 IBIPORÃ" pasture (61P), "IAPAR 61 IBIPORÃ" cover crop (61SM), "Embrapa 139 (Fog)" oat hay (139F),"Embrapa 139 (Fog)" pasture (139P)," Embrapa 139 (Fog)" cover crop (139SM), "Emerald IPR 126" oat hay (EF), "Emerald IPR 126" grazed (EP) and "Emerald IPR 126" cover crop (ESM) from which we evaluated the decomposition of the remaining straw using the method of litter bags. The evaluations were carried out at 0, 15, 30, 60, 90 and 108 days after sowing corn for silage intercropped with Brizantha brachiaria cv. MG13 Braúna (Urochloa brizantha). Every oat cultivar had three repetitions arranged in a split-plot design. We took into account the quantity of straw, organic matter, carbon, nitrogen, carbon / nitrogen ratio, phosphorus and potassium. The results we got clarify that oat decomposition rate varied with the meteorological factors and initial mass, so that the greater the initial mass is, the longer the straw permanency and mulch effectiveness on the soil. The time the residual oat straw took to be decomposed depended on meteorological factors both during the cover crop developmental stage and the decomposition period itself. The higher the initial mass, the greater the time and effectiveness of mulching.

A soja é uma cultura de destaque e tem grande potencial, mas que pode ser afetada pela toxidez por alumínio presente na maioria dos solos brasileiro. Diante disso, o objetivo do trabalho foi avaliar o efeito de doses elevadas de calcário calcítico sob as características agronômicas da cultura, bem como a influência na absorção dos nutrientes Ca, Mg e K em plantas de soja em duas safras agrícolas no município de Marechal Cândido Rondon. O estudo foi desenvolvido na área experimental da UNIOESTE, campus Marechal Candido Rondon, em um Latossolo Vermelho eutroférrico empregando doses de calcário calcítico (0, 3, 6 e 9 t ha-1) distribuído a lanço sem incorporação. Observou-se efeitos das doses em dois anos agrícolas 2017/2018 e 2018/2019 quando foram avaliados caracteres agronômicos altura de plantas, número de plantas por hectare, diâmetro do caule, número de vagens por planta, número de grãos por planta, massa de mil grãos, produtividade e os teores de nutrientes foliares. Não houve influência das doses de calcário calcítico nas características agronômicas da cultura da soja. Pode ser observado influência das doses de calcário calcítico no acúmulo nutricional de Ca no tecido foliar na dose de 6 t ha-¹. As doses de calcário calcítico proporcionaram redução nos teores de K. O Mg foi influenciado apenas pelo ano agrícola, apresentando maior acúmulo em plantas no segundo ano agrícola.

This study aimed to evaluate the decomposition and release of nutrients from the remaining straw of two annual forage species conducted in an integrated crop-livestock system (ICLS). The experimental design used was randomized blocks, in split plots, with three replicates. The managements were allocated in the plots (52 m2): without grazing, one grazing, and two grazings. Subplots were defined by material collection times after the forage’s desiccation (0, 30, 60, 90, and 120 days after desiccation). Dry matter yield, amounts of carbon, nitrogen, phosphorus, and potassium, and half-life time were evaluated. Oat cultivar IPR Esmeralda had the highest initial dry matter yield (6,099 kg ha-1) when not grazed, while triticale cultivar IPR 111 showed the highest average values when subjected to grazing (8,088 kg ha-1). The amounts of N, P, and K released from the remaining dry matter, regardless of the management adopted, decreased over time. Potassium was the nutrient that presented the most accelerated release, with an average half-life of 14 days. When subjected to grazing, triticale is more efficient in nutrient cycling, providing 197, 38, and 231 kg ha-1 of N, P, and K, respectively, with a half-life time of 10, 37, and 25 days, respectively. Forage species can improve the cycling of nutrients and make them available to crops in succession in the ICLS.

The main cause of decreased soil fertility and soil organic matter content is intensive crop farming with inadequate management. This study aimed to evaluate soil chemical properties, total organic carbon content, physical granulometric fractions (particulate organic carbon and mineral-associated organic carbon), carbon stocks, and carbon management indices of oxisols in different integrated agricultural production systems (IAPSs) with reference to values in a haymaking area and native forest. The experiments were performed using completely randomized design, considering nine differently managed areas, including seven IAPSs and two reference areas (haymaking area and native forest); four soil samples from the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m layers were randomly collected from each area and the abovementioned variables were evaluated. The results showed no differences in variables between the managed and reference areas, indicating the maintenance of fertility and carbon fractions. Therefore, the tested management strategies promote beneficial modifications of soil properties. Producers should adopt different IAPS management strategies for soil preservation. The main cause of decreased soil fertility and soil organic matter content is intensive crop farming with inadequate management. This study aimed to evaluate soil chemical properties, total organic carbon content, physical granulometric fractions (particulate organic carbon and mineral-associated organic carbon), carbon stocks, and carbon management indices of oxisols in different integrated agricultural production systems (IAPSs) with reference to values in a haymaking area and native forest. The experiments were performed using completely randomized design, considering nine differently managed areas, including seven IAPSs and two reference areas (haymaking area and native forest); four soil samples from the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m layers were randomly collected from each area and the abovementioned variables were evaluated. The results showed no differences in variables between the managed and reference areas, indicating the maintenance of fertility and carbon fractions. Therefore, the tested management strategies promote beneficial modifications of soil properties. Producers should adopt different IAPS management strategies for soil preservation.

The coffee plant can grow together with different plants, but the presence of allelochemicals can affect the crop post-planting. This study aimed to evaluate the early growth of coffee seedlings following treatment with plant extracts from different botanical families. The experimental design used randomized blocks with four trials, in a 7 × 2 factorial scheme; the first factor consisted of aqueous extracts from six species: canola, crotalaria, brachiaria, sunflower, wheat, and lupine; water was used as the control. The second factor comprised of different botanical parts of the aforementioned six species of plant. The extracts were diluted to 5% concentration and were applied at a dose of 20 mL per plant. The agronomic variables analyzed were plant height (PH), stem diameter (SD), leaf area index (LAI), leaf dry matter (LDM), root dry matter (RDM), and root length (RL). Compared to the canola extract, the application of brachiaria extract resulted in the best response in PH, regardless of the botanical part that constituted the extract, leading to an increase in PH by 3.77 cm. The agronomic character most sensitive to the application of aqueous extracts was PH, in which the brachiaria extract was prominent in inducing the greatest growth, whereas the canola extract hindered the initial development of Arabica coffee seedlings. The coffee plant can grow together with different plants, but the presence of allelochemicals can affect the crop post-planting. This study aimed to evaluate the early growth of coffee seedlings following treatment with plant extracts from different botanical families. The experimental design used randomized blocks with four trials, in a 7 × 2 factorial scheme; the first factor consisted of aqueous extracts from six species: canola, crotalaria, brachiaria, sunflower, wheat, and lupine; water was used as the control. The second factor comprised of different botanical parts of the aforementioned six species of plant. The extracts were diluted to 5% concentration and were applied at a dose of 20 mL per plant. The agronomic variables analyzed were plant height (PH), stem diameter (SD), leaf area index (LAI), leaf dry matter (LDM), root dry matter (RDM), and root length (RL). Compared to the canola extract, the application of brachiaria extract resulted in the best response in PH, regardless of the botanical part that constituted the extract, leading to an increase in PH by 3.77 cm. The agronomic character most sensitive to the application of aqueous extracts was PH, in which the brachiaria extract was prominent in inducing the greatest growth, whereas the canola extract hindered the initial development of Arabica coffee seedlings.

The objective of this study was to evaluate the effect of two sowing densities of oat crop, managed in an integrated crop-livestock system (ICLS), or the use of fallow during the winter period, on the soil physical properties, total carbon and soil carbon stock, in two years. A split-plot in a randomized block design, with additional treatment was used. It was found that the number of grazing in the year 2014 adversely affected the values of macroporosity and microporosity in the layer 0-0.05 m, besides the microporosity in the 0.1-0.2 m layer. The total porosity in the 0.1-0.2 m layer was positively influenced by the sowing density of oats only in the year 2014. The soil penetrometer resistance (SPR) had changes after winter 2015, at 0-0.05 m due to the number of grazing. During 2014, there were no changes in the total carbon and carbon storage of the soil. In 2015, the amount of grazing used, negatively affected the total carbon in layers 0-0.05 and 0.1-0.2 m. However, it positively affected the storage of carbon in soil in the layer 0.05-0.1 m. The adoption of the lower density of the oat crop with realization of a grazing tends to improve the physical properties, total carbon and soil carbon stocks.

Distribution of organic matter fractions of an Oxisol under different integrated agricultural production systems. AUTHORS Juan López-Herrera, Augusto Rocha de Moraes Rego, Paulo Sergio Rabello de Oliveira, Eloisa Mattei, Antonio Saa-Requejo.E-mail: juan.lz.herrera@upm.es, cassielcarlos@hotmail.com, rabelo.oliveira@hotmail.com, eloisa-mattei@hotmail.com, antonio.saa@upm.esAbstractThe declining organic matter content (OM) in agricultural soils is due mainly to poor agricultural management as soil fertility is closely related to OM. This work studies the variation in the different fractions of the OM in 7 plots with different agronomic management following integrated agricultural production system (IAPS) with different type of management. Six plots presented two crops per year, one of oats grown in autumn-winter and then soybeans grown in spring-summer. Seed doses per hectare and the management of livestock grazing were different among them. The seventh plot had a natural resection of rye and forage turnip during the winter, with succession of soybeans in spring-summer. Two reference plots were selected with hay and native forest production. These IAPS were compared at two areas, haymaking area and native forest, classified as Oxisols.In each plot, random samples were analyzed at three different soil horizons, between 0.00-0.05, 0.05-0.10 and 0.10-0.20 m. Based on the soil samples the following parameters were measured: Total Organic Carbon (TOC), Particulate Organic Carbon (POC) associated with sand fraction, carbon stock (TOCst), mineral-associated organic carbon (MOC) associated with silt and clay, and humic substances (Fulvic Acids FA, Humic Acids HA and humin HUM). The relationship between these seven carbon indices and the seven IAPS were statistically analyzed using Tocher's multivariate non-hierarchical grouping methods.The results pointed out that the different fractions of MO minus AH have a positive correlation in the three layers studied compared to the native forest. Therefore, IAPS management strategies promote beneficial modifications to soil properties and are beneficial for soil preservation. The management systems studied can serve as options for producers who wish to replace exclusive hay production with integration between crops and livestock in an Oxisol area similar to this one. Finally, the adoption of these management systems can lead to better soil preservation and increased economic benefits. Keywords: integrated crop-livestock system, soil management, fractions of soil organic matter. ReferenceREGO, C. A. R. M.; OLIVEIRA, P. S. R.; PIANO, J. T.; ROSSET, J.S.; EGEWARTH, J. F.; MATTEI, E.; SAMPAIO, M. C.; LOPEZ-HERRERA, J.; GONÇALVES JUNIOR, A. C. (2020). Chemical properties and physical fractions of organic matter in oxisols under integrated agricultural production systems. Revista de Agricultura. Neotropical, Cassilândia-MS, v. 7, n. 3, p. 81-89, jul./set. 2020. ISSN 2358-6303. REGO, C. A. R. M.; OLIVEIRA, P. S. R.; PIANO, J. T.; EGEWARTH, J. F.; EGEWARTH, V. A.; LOPEZ-HERRERA, J. (2020). Organic Matter Fractions and Carbon Management Index in Oxisol Under Integrated Agricultural Production Systems. Journal of Agricultural Studies, 2020, Vol. 8, No. 3 ISSN 2166-0379 https://doi.org/10.5296/jas.v8i3.16325

The objective of this work was to evaluate the carbon content of the physical, chemical and oxidizable fractions of soil organic matter (SOM) and to calculate the carbon management index (CMI) in an area managed under an integrated crop-livestock system (ICLS) in the western region of Paraná - Brazil. The experiment was carried out at the experimental farm, belonging to the Universidade Estadual do Oeste do Paraná. Seventeen areas, which are managed in different ways, fifteen in ICLS and two areas of controls (Forest and Haymaking), using the design divided with two nested controls, with three replications were evaluated. Deformed and undisturbed soil samples were collected from all the areas to determine the total organic carbon (TOC), carbon stock, the physical, chemical and oxidizable fractions of SOM and the CMI in the layers of 0-0.05, 0.05-0.1 and 0.1-0.2 m. Little significant changes in the fractions were found for the management of the ICLS area in relation to the Forest and the area of Haymaking, although the Forest presented the best values for most of the studied fractions. It is recommended to adopt sustainable practices, such as ICLS, even though the average fractions tend to take time to match reference areas. O objetivo desse trabalho foi avaliar os teores de carbono das frações física, química e oxidável da matéria orgânica do solo (MOS) e calcular o índice de manejo de carbono (IMC) em uma área manejada em sistema de integração lavoura pecuária (ILP) na região Oeste do Paraná - Brasil. O experimento foi realizado na fazenda experimental, pertencente à Universidade Estadual do Oeste do Paraná. Foram avaliadas dezessete áreas, que foram manejadas de diferentes formas, quinze em ILP e duas testemunhas (Mata e Fenação), sendo empregado o delineamento subsubsubdividido com duas testemunhas aninhadas, com três repetições. Em todas as áreas foram coletadas amostras deformadas e indeformadas de solo para serem determinados o carbono orgânico total, estoque de carbono e as frações físicas granulométricas, oxidáveis e químicas da MOS e o IMC nas camadas de 0-0,05, 0,05-0,1 e 0,1-0,2 m. Alterações pouco significativas das frações foram encontradas para os manejos da área em ILP em relação a mata e a área de fenação, entretanto a mata apresentou os melhores valores para a maioria das frações estudadas. Recomenda-se a adoção de práticas sustentáveis, como a ILP, mesmo que os teores médios das frações tendem a demorar tempo para igualar-se a áreas de referência.

The objective of this study is to identify and quantify the floristic composition of the weed community in the rice crop waterlogged in the municipality of Arari-MA. The botanical material was obtained in three areas by randomly a hollow rectangle of 0.50 m × 0.30 m by forty five times in each plot. The aerial parts of weeds were harvested, identified, counted and oven dried with forced air ventilation at 333.15 K to 343.15 K. These data were used to determine the phytosociological parameters and the Shannon-Wiener diversity index was also calculated. A total of 6607 plants were collected, being 4115 (62.28%) in the vegetative phase and 2492 (37.72%) in the reproductive phase. The monocotyledonous group obtained the largest number of plants, 2882 in the vegetative phase and 1535 in the reproductive phase. The Cyperaceae family recorded nine species and four genera and the Poaceae, seven and four species in the vegetative and reproductive phases, respectively. The species of higher IVI in the vegetative phase was E. sellowiana in the area A1 with 82.86%, and in the reproductive F. dichotoma with IVI of 90.49% in the area A3. The individuals density and species richness were higher in the vegetative phase of the culture and the monocotyledonous group predominated with the Cyperaceae and Poaceae families, and the weed diversity among the areas was low.

Muitos produtores resistem em adotar a presença dos animais nas lavouras, pois acreditam que possa compactar o solo e causar redução na produtividade da cultura em sucessão. Diante disso, objetivou-se avaliar os atributos químicos e físicos do solo após o cultivo de forrageiras invernais sob manejos de pastejo e soja em sucessão em sistema de integração lavoura-pecuária. O experimento foi conduzido em um LATOSSOLO VERMELHO sob o delineamento de blocos ao acaso, em esquema de faixas, com três repetições. Foram testados diferentes forrageiras invernais (aveia BRS 139, aveia preta IPR 61, aveia branca IPR Esmeralda, Triticale 111 Tpolo e o consórcio de Triticale 111 TPolo e aveia IPR Esmeralda), manejos de pastejo (sem pastejo, um pastejo e dois pastejos) e profundidades do solo (0-0,05, 0,05-0,10 e 0,10-0,20 m). Foram determinados os seguintes atributos: nitrogênio total (NT), carbono orgânico total (COT), relação carbono e nitrogênio (C/N), matéria orgânica do solo (MOS), porosidade total (Pt), macroporosidade (Mac), microporosidade (Mic) e densidade aparente (Ds). As forrageiras utilizadas para pastejo no período de inverno resultaram em diferentes teores de MOS, NT e Mac. O cultivo do Triticale 111 TPolo resultou em menor Mic e Pt quando manejado sob dois pastejos nas camadas de 0,05-0,10 e 0,10-0,20 m e a maior Ds foi encontrada na camada superficial, independentemente da forrageira e manejo. As forrageiras invernais quando submetidas a pressões de pastejo não modificaram os atributos do solo entre as profundidades avaliadas.

This work aimed to evaluate the oxidizable and chemical fractions of organic matter and the carbon management index in different integrated agricultural production systems, hay production and native forest areas in an Oxisol. Nine areas with different management systems were evaluated being six managements of the combination between different oat density (40 and 60 kg ha-1) and grazing frequencies (0, 1 and 2) in autumn-winter and soybean succession in spring-summer, one with natural reseeding ryegrass and forage turnip in autumn-winter and soybean succession in spring-summer and two reference areas. In each soil management systems were collected soil samples composite in the 0-5, 5-10 and 10-20 cm layers and determined the Total Organic Carbon (TOC), humic substances (Fulvic Acids - FA, Humic Acids - HA and humin - HUM), the carbon in the oxidizable fractions (F1, F2, F3 and F4) and Carbon Management Index (CMI). Were observed that chemical, oxidizable fractions and CMI, do not have significant differences between with the various managements each other. For TOC, HA, HUM, F1, F3, F4 and CMI, the managements did not differ from the reference areas indicating maintenance of soil carbon.

The objective of this work was to evaluate the production components, grain yield and safflower character correlations as a function of two sowing seasons (autumn and winter). Safflower culture was implanted in 2014 in a randomized complete block design with three replicates. The evaluation of safflower crop occurred in two seasons of the year, with the first growing season being characterized by sowing on April 30, 2014 (autumn), and the second growing season on July 30, 2014 (winter). The evaluations occur when the plants showed a 50% flowering and the following determination: plant height, number of branches per plant and chapters, stem diameter, dry weight of the stalk, dry mass of the branches dry mass of chapters and mass dry roots, grain yield, oil content and oil productivity. Growth stations were compared at 5% probability of error by the Student t test. For the study of correlations, Pearson’s linear correlation coefficient matrix (r) was estimated between the characters by means of the Student’s t-test, with a 5% probability of error. Except for the oil content and number of branches, safflower characters were benefited by early sowing in autumn. Safflower cultivated in autumn produced 3,820 kg ha-1 and in winter yielded 2,068 kg ha-1. For the early cultivation of autumn, the characters have greater correlation, favored by the climatic conditions. Grain and oil productivity obtained correlation higher than 97% in both seasons.

In the face of the traditional model of succession of native environments in pastures or agricultural areas, followed by superpastejo and the concern with emissions of greenhouse gases in the Brazilian Amazon region, this work aims to determine the influence of different land uses on carbon sequestration and soil organic matter changes in the municipality of Pindaré-Mirim, in state of Maranhão. This study evaluated different uses of the soil: native forest; secondary vegetation (capoeira); degraded pasture and CLFI (Crop-Livestock-Forest Integration) system. The deformed and undisturbed samples were collected at depths: 0.00-0.10, 0.10-0.20, 0.20-0.30, 0.30-0.40, 0.40-0.60, 0.60-0.80 and 0.80-1.00 m. Soil densities were determined by the volumetric ring method, the carbon stocks by the carbon content in the soil evaluating the dry combustion, and the accumulated carbon stocks were calculated in 1.00 m. The physical fractions of the organic matter were determined by means of the granulometric method. At depth 0.0-0.10 m, the soil density in the native forest (1.17 g cm-3) was lower than the average of degraded pasture (1.40 g cm-3). There was no difference in the carbon content between all the land uses up to 0.40 m depth. The accumulated carbon stocks up to 1.00 m ranged from 49.52 Mg ha-1 to 64.41 Mg ha-1 and were higher in the native forest compared to capoeira and the ICLF system. In relation to the accumulated carbon stock, the native forest and degraded pasture were the ones that obtained the highest levels, followed by the capoeira and the CLFI system.

The sustainability of ecosystems is closely linked with the assessment of soil properties that estimate their quality. This work proposes to evaluate soil chemical attributes as a function of the implantation of a crop-livestock-forest integration system (ICLF) in the region of Mata dos Cocais in the state of Maranhão, Northeast Brazil. The four different land uses evaluated were native vegetation with babassu, capoeira vegetation, degraded pasture and area under ICLF system (with marandu grass, maize and eucalyptus consortium). The samples were collected up to one meter deep, comprising seven layers: 0.00-0.10, 0.10-0.20, 0.20-0.30, 0.30-0.40, 0.40-0.60, 0.60-0.80 and 0.80-1.0 m. The chemical attributes evaluated were pH, Ca, Mg, Al, P, K and Na, potential acidity, base sum, base saturation and soil cation exchange capacity (CEC). The levels of P, in the 0.00-0.10 m layer, were higher in the ICLF system than those of the native forest with babassu. The levels of K in the ICLF system and degraded pasture were higher than the other land uses up to a depth of 0.40 m, ranging from 0.92 cmolc dm-3 to 0.62 cmolc dm-3 and 1.04 cmolc dm-3 and 0.67 cmolc dm-3, respectively. Base saturation was higher in soils under ICLF system and degraded pasture than those observed in native forest and capoeira vegetation. There was an effect in chemical attributes of the soil such as a function of land use and, in general, the highest values were found in areas with degraded pasture and ICLF.

Soil organic matter is degraded and easily altered by the type of management. The objective of this work is to determine the total organic carbon and humic substance fractions in the organic matter of the soil with different management types and depths in the western region of Paraná, Brazil. The work was carried out in the Experimental Farm “Professor Antônio Carlos dos Santos Pessoa”, belonging to the State University of the West of Paraná. Five soil management systems were evaluated: one area with corn cultivation for silage (CS); other area with succession of crops, with soybean in summer and corn in winter (SC); the next area also with succession of crops, with soy in the summer and oat in the winter (SO); the following area with permanent pasture with Tifton (PP); and the last area with crop-livestock integration (ILC). For each management system, four plots were randomly selected, in each plot three simple samples were collected in a diagonal direction to form a composite sample for the depth of 0.00-0.05 m, 0.05-0.10 m and 0.10-0.15 m. Total organic carbon, fractionation of the humic substances and the AH/AF and EA/HUM ratios were calculated. For most of the analyzed variables, it was verified that there were significant differences (P < 0.05) between the systems evaluated in the studied depths. In the evaluated areas, the PP, SO and ILC systems presented the highest carbon content for all attributes analyzed.