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Land management practices that overlook soil limitations and potential have led to varying degrees of degradation. This study evaluates the carbon content in chemical and oxidisable soil fractions across different pasture recovery periods, comparing them to secondary forests. The management practices assessed include the following: secondary forest (SF), perennial pasture (PP), perennial pasture recovered five years ago (P5), and perennial pasture recovered eight years ago (P8), all on Plinthosols. We analysed carbon levels in oxidisable fractions and humic substances at depths of 0–0.10 m, 0.10–0.20 m, 0.20–0.30 m, and 0.30–0.40 m. The SF and P8 areas showed the highest organic matter content within the humic fractions, compared to the PP and P5 areas. Additionally, the P8 area demonstrated an increase in the labile and moderately recalcitrant fractions of organic matter, standing out among the different fractions evaluated. The multivariate principal component analysis indicated that P8 has the greatest impact on soil quality, followed by FS, P5, and PP. The pasture recovery over the past eight years has significantly improved soil carbon accumulation, highlighting the benefits of land restoration.

In Maranhão State, Brazil, soils are naturally acidic, nutrient-deficient, and prone to cohesion and erosion. Removing the natural cover to establish pastures causes physical, chemical, and biological changes in the soil. Therefore, this study aimed to evaluate the contents and stocks of carbon (C), nitrogen (N), and particle-size fractions of soil organic matter (SOM) in pastures with different years of recovery, and compare them with a secondary forest in the Legal Amazon. Four treatments were evaluated: secondary forest, perennial pasture, and perennial pastures recovered for five years and eight years, both of the latter through corn + brachiaria intercropping. The contents and stocks of total organic carbon, total nitrogen, C, and N from the soil organic matter particle-size fractions, as well as the carbon management indexes (CMI) of the 0.00–0.10, 0.10–0.20, 0.20–0.30, and 0.30–0.40 m layers were evaluated. The perennial pasture environment presented the highest total soil C and N contents; however, when observing the granulometric fractions and CMI, these increases were qualitative in relation to the secondary forest. Pasture recovery over eight years contributed to an improvement of soil quality similar to secondary forest, indicating that an increase in SOM quality, quantity, and recovery time related to increased pasture capacity to accumulate C and N in the soil.

ABSTRACT Soil quality can be understood as its capacity to provide several essential services within the ecosystem and has been used to understand the impact of different managements, providing information that proves the benefits and your maintenance of the agroecosystem. To understand the impact of different managements, this study aimed to compare the chemical, physical, and biological soil properties in pasture areas managed with different recovery times in an integrated crop-livestock system about perennial pastures and secondary forest. The following management systems were evaluated: Secondary Forest (SF), Perennial Pasture (PP), pasture recovered to five years through the intercropping corn + Brachiaria brizantha (Palisade grass) (ICL5), and pasture recovered to eight years through the intercropping corn + Brachiaria brizantha (Palisade grass) (ICL8). Different soil properties were evaluated, namely: Chemical: pH, H+Al, Al 3+ , P, K + , Ca 2+ , Mg 2+ , TOC, SB, CEC, V, and m; Physical: soil bulk density (Bd), total porosity (Tp), macroporosity (Ma), microporosity (Mi), soil resistance to penetration (Pr), and gravimetric soil water content (GWc); and biological: soil microbial biomass carbon (SMB-C), basal soil respiration (BSR), metabolic quotient (qCO 2 ), and microbial quotient (qMic). Perennial pasture and ICL8 areas were the ones that most contributed to the increase in nutrients (Ca 2+ , Mg 2+ , and K + ), TOC and sorption complex. The ICL8 area showed the best results in soil physical variables Ma, Tp, Pr, and GWc were the best results for the ICL8 area. Secondary forest and ICL8 areas presented the best results from SMB-C and qMic. Between periods of pasture recovery through the integration of crops and livestock, the longer the recovery time, the greater its beneficial effects on the different chemical, physical and biological soil properties, overcoming secondary forest and perennial pasture.

This study aimed to evaluate the effect of the integrated crop-livestock system on the contents and stocks of total organic carbon, total nitrogen, and soil organic matter. The experiment was carried out between April 2016 and February 2017, in a randomized block design in a strip-block scheme, with additional control treatment (fallow) and four repetitions. The treatments consisted of two densities of oat sowing (40 and 60 kg ha-1) in strips A and different grazing frequencies (without grazing - WG, one grazing - 1G, and two grazing - 2G) in strips B, besides fallow as a control treatment. The determinations of the contents of total organic carbon (TOC), total nitrogen (TN), and organic matter (SOM) were carried out in the soil layers of 0-5, 5-10, and 10-20 cm. Samplings were carried out after oat management, in the winter, and after soybean harvest, in the summer. The sowing density of black oats and the grazing frequencies were not able to promote changes in the total organic carbon and in the TOC stock, regardless of the time of evaluation. The use of 40 kg ha-1 of oat seeds would be recommended, as it does not promote changes in the increase in MOS, thus generating savings in the acquisition of seeds. The use of the lowest density of oat without grazing and one grazing promoted changes on the total nitrogen in the 5-10 cm layer after the removal of oats, when compared to the fallow, and it presented content similar to the management with two grazings.

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 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 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.

Os sistemas integrados de produção lavoura-pecuária (SIPAs) em associação ao sistema de semeadura direta, sofrem ação do pisoteio animal ou do tráfego intenso de máquinas agrícolas, podendo resultar em alterações nas propriedades físicas do solo. O objetivo deste trabalho foi avaliar o efeito da adubação nitrogenada e manejos das forrageiras tropicais nas propriedades físicas do solo. O experimento foi realizado entre outubro de 2017 e janeiro de 2020, em Marechal Cândido Rondon – PR, em blocos ao acaso, com parcelas sub-subdivididas com uma testemunha adicional e quatro repetições. As parcelas foram constituídas por duas espécies forrageiras consorciadas com o milho: Urochloa brizantha e Magathyrsus maximum, mais a testemunha adicional (milho solteiro). As subparcelas consistiram nos manejos das forrageiras: fenação e pastejo; e nas sub-subparcelas, a presença ou ausência de adubação nitrogenada. Foram determinadas: densidade do solo (Ds), porosidade total (Pt), macro (Ma) e microporosidade (Mi), além da resistência do solo à penetração (Rp). A utilização de nitrogênio (N) em cobertura nas forrageiras após os manejos, aumentou a quantidade de Ma na camada de 0-0,05 m para o primeiro ano. Os valores de Ds estão acima do limite considerado crítico para o desenvolvimento das plantas, porém, com tendência à redução. A adoção do SIPA, independente da espécie forrageira utilizada e manejo adotado, seja fenação ou pastejo, não comprometeu a qualidade física do solo, sendo assim, uma ótima alternativa para a diversificação da produção na propriedade.

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.

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.

This study aimed to evaluate the decomposition and nutrient release from residues of the culture of oats and fallow in crop-livestock integration system. The experimental design was a randomized complete block design with two replications, as parcels being formed by four managements (fallow, oats without grazing, oats grazed once and twice), and the subplots for evaluation periods along the soybean crop in succession (0, 10, 20, 30, 50, 100 and 120 days after sowing). The residual amounts of dry matter and the contents of Carbon (C), Nitrogen (N), Phosphorus (P) and Potassium (K) were determined. Oats without grazing and fallow with natural reappearance of turnip + ryegrass were the treatments that presented the highest amount of dry matter remaining, reaching 5,219 and 6,781 kg ha-1, respectively. The amount of nutrients, N, P and K released from the residues, were similar independent from the management adopted, with exponential reduction proportional to the reduction of the remaining dry matter. K was the nutrient released faster from the residues and should be considered at the time of fertilization calculation of the culture to be implanted. The integrated crop-livestock system in which takes place one and two grazing oats, even reducing soil cover, enables high nutrient cycling.

This study aimed to evaluate the decomposition and nutrient release from residues of the culture of oats and fallow in crop-livestock integration system. The experimental design was a randomized complete block design with two replications, as parcels being formed by four managements (fallow, oats without grazing, oats grazed once and twice), and the subplots for evaluation periods along the soybean crop in succession (0, 10, 20, 30, 50, 100 and 120 days after sowing). The residual amounts of dry matter and the contents of Carbon (C), Nitrogen (N), Phosphorus (P) and Potassium (K) were determined. Oats without grazing and fallow with natural reappearance of turnip + ryegrass were the treatments that presented the highest amount of dry matter remaining, reaching 5,219 and 6,781 kg ha-1, respectively. The amount of nutrients, N, P and K released from the residues, were similar independent from the management adopted, with exponential reduction proportional to the reduction of the remaining dry matter. K was the nutrient released faster from the residues and should be considered at the time of fertilization calculation of the culture to be implanted. The integrated crop-livestock system in which takes place one and two grazing oats, even reducing soil cover, enables high nutrient cycling.

The ethnobotany looks at how different human groups interact with the vegetation. The aim of the job was to conduct a study of traditional community and the relationship of use of plant species in Settlement Pedra Suada, Cachoeira Grande, Maranhão, Brazil. The methodology used was the application of semi-structured questionnaires. Women accounted for 58% of the public identified as having knowledge about use of plants in the settlement. The main activity carried out among respondents was farmer (a), with 64% of the total described occupation. 81 species were recorded, which were identified 42 plant families and one has not been identified. Lamiaceae family is the most represented species, 10 (12,35%), followed by Fabaceae 6 (7,41%), Rubiaceae 5 (6, 18 %), Apocynaceae, Anacardiaceae 4 (4,94%), Arecaceae, Amaranthaceae, Malvaceae, Euphorbiaceae and Bignoniaceae 3 (3,7%), and another 32 families with 37 species (45,68%). Among the species reported 55,6% had the use described as exclusively medical and 43,2% for multiple use. Among the diseases mentioned by the respondents of the digestive tract are the most cited with treatment using plants, associated with local knowledge, representing 18,6%. The form of manipulation of medicinal most used among respondents was in the form of tea (56,9%). The record local knowledge about the uses of native plants in the region will allow the rescue and dissemination of that knowledge.

Many producers resist adopting the presence of animals on farms, as they believe that it can compact the soil and cause reduction in crop productivity in succession. Thus, it was aimed to assess the chemical and physical soil properties after cultivation of winter forage under different managements grazing and soybean crop in integrated crop-livestock system. The experiment was carried out in a Red Latosol on a randomized block design, in strip plots and three replications. Were tested different winter forages (oat BRS 139, black oat IPR 61, white oat IPR Esmeralda, Triticale 111 Tpolo and the consortium of Triticale 111 TPolo and oat IPR Emerald), grazing managements (without grazing, one grazing and two grazing) and soil layers (0-0.05, 0.05-0.10, and 0.10-0.20 m). Total nitrogen (NT), total organic carbon (TOC), carbon and nitrogen ratio (C/N), soil organic matter (MOS), total porosity (Pt), macroporosity (Mac), microporosity (Mic) and apparent density (Ds) were determined. The forage plants used for grazing in the winter period resulted in different levels of MOS, NT and Mac. The cultivation of Triticale 111 TPolo resulted in lower Mic and Pt when managed under two grazing in the 0.05-0.10 and 0.10-0.20 m layers and the highest Ds was found in the surface layer, regardless of the forage and management. The winter forages when submitted to different grazing pressures did not change the soil attributes between the evaluated layers.