http://localhost:8080/handle/prefix/129 2026-11-09T22:50:26Z http://localhost:8080/handle/prefix/181 Title: Qualidade do solo na cultura do arroz cultivado em várzea roraimense Autor(es): Evald, Ariane Primeiro Orientador: Melo, Valdinar Ferreira Abstract: The search for sustainable agriculture has promoted the development of research in the soil field aimed at understanding the behavior that soil presents in response to different managements and crops. A large number of researchers has focused its efforts on identifying soil properties that are more efficient in inferring soil quality due to soil changing as result from use and management. The aim presented in this study was to evaluate the soil quality by chemical properties, soil microbiological and biochemical in an area with waterlogged rice cultivation under different years of cropping. The areas have the following rice cultivation times (1, 3, 8, 13 and 25 years) compared to a nature area (reference). Composite samples with four replications were collected at 0-10 cm depth. They were separated into two sub-samples, one for chemical analysis and one for microbiological and biochemical analysis, which were stored under cooling. In the laboratory the chemical attributes evaluated were: soil organic carbon (SOC), total nitrogen (TN), P available, K+, Ca2+, Mg2+ exchanges, Al3++H+ exchanges and pH, and calculated the CEC, and C/N ratio. The microbiological attributes were: microbial biomass carbon (MBC), microbial respiration (MR), calculated the CO2 coefficient (qCO2) and microbial coefficient (qMIC). The enzymes activities of acid phosphatase and urease were evaluated. The different years of rice cultivation were significantly different from the nature area in most of the soil indicators assessed, with higher expressivity, especially to SOC, NT, P, CBM and acid phosphatase variables. In the principal component analysis was observed the formation of two main groups of components (CP). SOC, C-BMS and NT were the main variables of the CP1, the acid phosphatase indicators, Mg2+ and P were the variables of greater expressiveness in CP2. The abrupt shift in soil quality from nature area converted to rice cultivation decreased the soil quality, but after 8 years of rice cropping the soil presented an improvement in soil quality. Publisher: Universidade Federal de Roraima Tipo: Dissertação 2016-04-29T00:00:00Z http://localhost:8080/handle/prefix/180 Title: Atributos químicos e matéria orgânica do solo sob diferentes sistemas de uso e manejo em ambientes de floresta de Roraima Autor(es): Espinoza Guardiola, Marden Daniel Primeiro Orientador: Vale Júnior, José Frutuoso do Abstract: The crop-livestock integration systems (cLI) crop-livestock integration forest (cLIF) and pasture have emerged as strong alternative to carbon incorporation and consequently improvement in physical and chemical characteristics of the soil. The objective of this work to evaluate the chemical attributes, organic matter in soils under Natural forest undertaken in different use systems and soil management: pasture (PAST), crop-livestock Integration (cLI) crop-livestock Integration forest (cLIF) and a Natural forest (NF) as a witness. The experimental design was completely randomized in plots scheme subdivided, with 24 treatments from the association between four systems and six different depths (0-10, 10-20, 20-40, 40-60, 60-80 and 80-100 cm), with four repetitions. The data subjected to analysis of variance, and significance through "F", the averages compared by Tukey test at 5% probability of error. cLI systems and PAST showed similarities in chemical attributes such as pH, Ca2+, Mg2+ and K+. pH showed no difference between the studied systems. For potential acidity (H + Al) the highest value for this variable was found in the cLIF area at a depth of 0-10 cm and the smallest in the pasture. Aluminum (Al3+) was superior in the NF. The sum of the bases (SB) presented the highest value in the PAST system. The saturation by bases (V %) was higher in the PAST in all the depths evaluated, and lower in the NF. The total cation exchange capacity (TCC), showed the highest value in the area of cLI in the depths 0-10 and 10-20 cm and the smallest values in the cLIF area at the depth of 20-40 cm. The chemical fractionation of soil organic matter (SOM) revealed that the cLIF area had the major value for Humina (HUM) and humic Acid (HA). The FN presented greater value for Fulvic acid (FA). The NF presented the largest value for Fulvic acid (FA). The particulate organic carbon (Cop) was greater at all depths in the PAST area. The organic carbon associated with minerals (Coam) presented the highest value for all systems in general in the 0-10 cm depth. The total organic carbon (TOC) was greater among the systems assessed in relation with the NF. Oxidizable fractions showed similar values in the lighter fractions (F1) and (F2), however, regardless of the evaluated area, it observed a predominance of the most recalcitrant fractions of MOS (F3) and (F4). The analysis of carbon stocks showed no significant difference but presented best values between systems in relation to FN. After this results, its concluded that management systems deployed showed higher values of Ca2+, Mg2+, Na+, and P in the surface layer (0-10 cm) of soil in relation to the NF. Humic substances (HA), (HUM) and the physical fractions (Coam) showed greater stability in management systems. The ratio AH/AF was greater in the PAST area and a reduced amount of in the cLI indicating that organic matter from ecosystems presents greater stability on the ground. The (HUM) showed higher levels, regardless of the area studied and analyzed depths. Therefore, the management systems evaluated positively influenced in the dynamics of the MOS when compared with NF. Publisher: Universidade Federal de Roraima Tipo: Dissertação 2016-03-09T00:00:00Z http://localhost:8080/handle/prefix/178 Title: Qualidade do solo em sistema de pastagem convertida ao cultivo de dendê (Elaeis guineenses Jacq.) Autor(es): Maldonado, Selvin Antonio Saravia Primeiro Orientador: Cordeiro, Antonio Carlos Centeno Abstract: The oil palm is a crop that has great economic potential, since its producti ve potential is extremely high, being culti vated in several countries of Asia, Africa and America. In Brazil, its culti vation is concentrated in only a few regions, distributed mai nly in the Northeast and North of the country. However, in spite of the few areas with commercial culti vation, the oil palm presents potential of planting due to the advantage of being able to intercalate different species, with emphasis on the recovery of altered areas and forest fragments. The objecti ve of this work was to study the soil quality in a pasture system converted to palm oil (Elaeis guineenses Jacq.), Under i ntercropping, established in an experimental area of Embrapa, i n the municipality of São João da Baliza, Boa Vista - RR, vicinal 26, Km 12, with geographic reference coordi nates 00º 51' 13,3''N and 60º 00' 19,8''W and an altitude of 100 m, i nstalled on a Red-Yellow Argisol. The planting systems had dimensions of 36 mx 39 m, formi ng a total area of 1,404 m². The experimental design was completely randomi zed, in a subdi vided plots scheme with 4 replicates for the chemical and physical analyzes, and completely randomi zed with 4 replicates for the microbiological and biochemical analyzes. The treatments consisted of 5 systems intercalated with palm, being: 1) i ntercalated with grass, Brachiaria h umidicola (DP); 2) pineapple, C v. Victory (DA); 3) Cowpea, Cv. Guariba (DF); 3) banana, Cv. Japira (DB); 4) cassava, C v. Amazonas (DM) and 5) grass, Brachiaria humidicola (PS). The physical and chemical attributes were evaluated in the layers 0-0.10 ; 0.10-0.30 and 0.30-0.50 m and i n the 0-0.10 m layer for the microbiological and biochemical attributes. It was found a heavier granulometry for the DM, DB and P systems which in turn presented higher formation and stabilization of aggregates denoted by high DMG, DMP and IS i ndexes, covering all this, under balanced macro and micropore conditions, i ncreases in total porosity and decrease of soil density. The highest values of pH, exchangeable Ca2+, Mg2+, K+ and the decrease of Al3+ i n the DM e DF intercalations s ystems were observed for all the layers evaluated, with high levels in the sorption complex, SB, C TCt and V. The area PS presented low ferti lity, originating from its natural conditions. Meanwhile, the systems that showed the best results and that contributed most to improve the soil microbiological and biochemical conditions were PS, DP and DM, positi vely influencing variables C-BMS, qCmic and the enzymatic activities of β-glucosidase, urease and acid phosphatase. Publisher: Universidade Federal de Roraima Tipo: Dissertação 2017-07-14T00:00:00Z http://localhost:8080/handle/prefix/177 Title: Influência de sistemas integrados de produção nas características físicas e químicas de um argissolo Autor(es): Cruz, Diego Lima de Souza Primeiro Orientador: Vale Júnior, José Frutuoso do Abstract: The Crop-Livestock-Forest Integration System (ILPF) is considered one of the most suitable conservationist systems for the recovery of degraded pastures, because it increases the efficiency of the area utilization. In this context, the present work was elaborated with the objective of comparing the management systems with a natural forest with the physical and chemical characteristics of Ultisol in the state of Roraima. The study was carried out in a private property with ILPF experiment installed in partnership with Embrapa-RR. There were 4 main treatments (Areas): T1 = Rotated Pasture; T2 = Natural Forest (NF); T3 = Crop-Livestock Integration (CLI); T4 = Livestock-Forest Integration (LFI); The secondary treatments were 6 depths: P1 = 0 to 10 cm; P2 = 10 to 20 cm; P3 = 20 to 40 cm; P4 = 40 to 60 cm; P5 = 60 to 80 cm; P6 = 80 to 100 cm in a completely randomized design in the spli-plot scheme. The evaluated properties were: Soil Penetration Resistance (PR), Texture, Soil Density (SD) and Soil Particle Density (PD), Total Porosity (TOP), Dispersed Clay in Water (DCW), Clay Flocculation Degree (CFD) , Soil Organic Matter (SOM), Soil Carbon Stock (SCS) and Soil Physic Quality Index (SPQI). Analyzing the set of all the properties and comparing the managed environments with the natural forest, considered as a parameter of physical soil quality, it was verified that there is no physical degradation of the soil in the management systems studied, being able to be indicated to be used as a recovery system for degraded areas. The high SD values in the CLI and LFI was a signal to the importance of implementing a physical soil quality monitoring program in the property, besides the control in the activities of machines and animals in those systems. Publisher: Universidade Federal de Roraima Tipo: Tese 2017-09-01T00:00:00Z