Scielo RSS <![CDATA[Engenharia Agrícola]]> vol. 38 num. 3 lang. en <![CDATA[SciELO Logo]]> <![CDATA[SPATIAL VARIABILITY OF THE MICROCLIMATE IN DIFFERENT SMALL RUMINANT HOUSE LOCATED IN THE SEMIARID OF PERNAMBUCO, BRAZIL]]> ABSTRACT The spatial variability in meteorological conditions was evaluated in two small ruminant house with different constructive aspects, based on the variables of dry bulb temperature, relative humidity, wind speed and temperature humidity index (THI), through the generation of maps using the Kriging interpolation method. The experiment was conducted in two seasons, winter and summer, and the small ruminant house were denominated as: FNRG (facility at ground level with no ridge vent) and FWRG (facility at ground level and with ridge vent). The studied parameters were recorded by portable digital sensors, thermo-anemometers and thermo-hygrometers, with data collections at 9 am and 3 pm. With the analysis of the spatial variability of the data, it was observed that the pens positioned in the central region of the two facilities had the least stressful places to animals in two seasons and two times, where the FWRG presented larger areas with lower temperatures, within the comfort zone, compared to the FNRG due to the presence of the ridge vents, were the least stressful places for the animals in the two seasons and at the two data collection times. At 9 am, in the winter and summer, both facilities presented comfortable conditions for the rearing of goats and sheep in the morning that were not observed at 3 pm. <![CDATA[PROTECTED ENVIRONMENTS AND SUBSTRATES FOR ACHACHAIRU SEEDLINGS]]> ABSTRACT The Achachairu (Garcinia humilis) is a Bolivian exotic fruit that has been produced and commercialized a few years in Brazil. Information about the production of high quality seedlings is essential for the implementation and the renewal of orchards. The objective was to evaluate protected environments and substrates for Achachairu seedlings. Two protected environments were evaluated, one covered with aluminized thermal reflector screen of 50% of shading and the other with Sombrite® of 50% of shading. Inside the protected environments were tested substrates derived from combinations of various proportions of cattle manure (CM), ravine soil (RS), medium vermiculite (MV), super fine vermiculite (FV) and sand (S). For each protected environment was adopted a completely randomized design with 5 replications of 5 seedlings. Protected environments were compared by analysis of groups of experiments. All substrates studied formed high quality seedlings for the implementation of Garcinia orchards, with low rates of aerial and root phytomasses, low rates between height and stem diameter, providing higher Dickson quality index. The Aluminet® promoted the best seedlings with larger shoot, root and total dry mass. <![CDATA[LED TUBS ARTIFICIAL LIGHTING SYSTEM IN BROILER PRODUCTION]]> ABSTRACT Light is important for the physiology and zootechnical development of broilers and is characterized by the type of source defined by the spectral emission and geometry of the lamp, as well as the intensity and spatial distribution of the illuminance. The aim of this study was to verify the influence of an artificial lighting system based on tubular Light Emitting Diode (LED) lamps on the productive performance of broilers. The study was carried out in two broiler houses located in Londrina-PR. The lighting system for one of the broiler houses was composed of 52 tubular LED bulbs of 18 W powers, and the control broiler house consisted of 75 incandescent bulbs with 60 W powers. This research was divided into two parts; the first phase was evaluated the environmental similarity (dry bulb temperature, air velocity, and illuminance) between the two broiler houses. The second was based on the zootechnical indexes: average body weight, feed intake, feed conversion and mortality. Only the illuminance variable differed statistically. The lighting system based on the use of a tubular LED lamp, with fewer points of illumination and more distant positioning between lamps and lower power installed, did not compromise the zootechnical performance. <![CDATA[THE TYPOLOGY OF BROILER HOUSE AND THE IMPACT IN THE LOCOMOTION OF BROILERS]]> ABSTRACT The large majority of broiler houses use two types of systems: dark-house system - DHP, and tunnel with curtain system - ATC. The objective of the present study was to evaluate the association and the prevalence of locomotion issues in the broiler commercial farming systems (DHP and ATC). For assessing the thermal environment and the litter quality, a completely random design was adopted using two factors (broiler houses, DHP and ATC) with 12 repetitions. To study the surface temperature of the broiler breast, and the locomotion ability (gait score) a completely randomized design was adopted in a double factorial scheme 2 × 2 (two houses typology vs. sex) with 24 repetitions. To verify whether the type of house and the sex were associated to broiler locomotion problems due to the lack in walking ability, and the presence of medular compression (spondylolisthesis) the logistic regression was applied to the analysis: odds ratio and relative risk. The chance of the poultry to present inability of walking was 3.80 times higher in the male population. The risk factor associated with the lack of walking ability of the poultry was correlated to the tunnel house with curtains, presenting a relative risk 1.58 times higher when compared to the dark-house with walls. There was not the relative risk of medular compression (spondylolisthesis) neither was found an association between the poultry’ sex and the type of house. The reduction in the male broiler locomotion ability might be associated with the rearing in the housing tunnel with curtains. <![CDATA[GREEN ROOF: SIMULATION OF ENERGY BALANCE COMPONENTS IN RECIFE, PERNAMBUCO STATE, BRAZIL]]> ABSTRACT Green roof is a technology that consists of the use of soil and vegetation installed in the roof of buildings, being a great solution to combat heat islands. Thus, this study aimed to compare micrometeorological changes and their effect on the energy balance of non-vegetated (slab) and vegetated building roofs by means of a simulation model calculated as a function of the reference evapotranspiration (ETo), determined by the Penman-Monteith method. This research was developed between February 1 and September 30, 2016, in the Charles Darwin Building's Parking Garage, Rio Ave Empreendimentos, Recife, PE, Brazil. For this, a weather station was installed on the external building slab. On the slab, sensible, latent, and soil heat fluxes corresponded to 75, 22, and 3%, respectively, of the energy balance. In the simulated green roof, these fluxes reached values of 6, 87, and 7%, respectively. The simulation model allowed determining the energy balance for the green roof, indicating a lower sensible heat flux (69%) and a higher latent heat flux (55%) when compared to those found in the slab. <![CDATA[NITROGEN, PHOSPHORUS AND POTASSIUM ACCUMULATION IN WATERMELON CULTIVARS IRRIGATED WITH SALINE WATER]]> ABSTRACT The use of saline water in agriculture has increased in the Brazilian semiarid due to low availability of good quality water for irrigated agriculture, being the selection of salt tolerant hybrids an alternative to reduce the effect of salinity on nutritional status of plants. So, the objective of this work was to evaluate the effect of salinity of irrigation water in the accumulation and partition of nutrients in the vegetable tissue of watermelon cultivars, in the region of Mossoro in the State of Rio Grande do Norte, Brazil. The treatments studied consisted of applying irrigation water with five electrical conductivities (EC1 = 0.57, EC2 = 1.36, EC3 = 2.77, EC4 = 3.86 and EC5 = 4.91 dS m-1), two watermelon cultivars and four samplings times (15; 29; 43 and 60 days after transplanting), arranged in a scheme of split plot(5x2x4) and outlined in complete blocksrandomized with four replications. The accumulated nutrients in plants were influenced by ECw, occurring a loss in comparison with the higher ECw of 24.1 and 36.4% in the accumulationof N and P in the vegetative part of plant and 37.8 and 30.1 % in the accumulation of P and K in the aerial part. The accumulation of N, P and K in the watermelon was influenced by plant age, with reduction at the end of the cycle. <![CDATA[CHEMICAL CHANGES OF SOIL AND WATER IN HILLSIDE AREAS UNDER INTENSIVE HORTICULTURE]]> ABSTRACT Inadequate and intensive management of soils can promote changes in their chemical attributes and impair the quality of surface and groundwater, especially in hillside areas. Therefore, the aim of this study was to identify possible changes in soil and water chemical composition of hillside areas cultivated with horticulture. For this, chemical attributes of three soil depths (0-10, 10-30, and 30-60 cm) were determined in three hillside positions (upper, middle, and lower thirds) of five hillside and adjacent forest areas, as well as water from reservoirs for agricultural use and human consumption. Compared with the forest area, horticultural areas present soil with lower organic matter content and CEC, but higher values of pH, base saturation, and contents of P, Ca, and K. In cultivated areas, CEC decreases from the upper to the lower hillside, without significant changes in other soil fertility parameters. Soil fertility decreases with depth, regardless of soil management and hillside position. Water from reservoirs adjacent to hillside areas with horticulture is more acidic and has a higher nitrate content, especially during rainy periods. <![CDATA[CASTOR BEANS QUALITY SUBJECTED TO DIFFERENT STORAGE TEMPERATURES AND PERIODS]]> ABSTRACT The control of the temperature of the storage air have the ability to improve a better preservation of some types of agricultural products. However, the most effective temperature for storage as well as the duration of storage varies between products. Therefore, special attention should be concentrated on the storage temperature and its effects on the integrity and longevity of the produce. The objective of the present study was to evaluate the effects of storage temperature and storage period on the quality of castor beans. Castor seeds with a water content of approximately 6.1% (w.b.) were stored for 180 days at temperatures of 15, 25 and 35 °C. The quality of the seeds was evaluated every 45 days throughout the study period by measuring dry matter loss, electrical conductivity, color, and the free fatty acid and peroxide content of the crude oil extracted. Our results indicated that: a) higher storage temperature negatively affect the quality of the seeds and the extracted oil; b) the negative effect of temperature increase with longer storage period; c) the storage temperature of 15 °C least affect the quality of castor bean and the extracted oil. <![CDATA[THERMODYNAMIC PROPERTIES OF SORPTION OF RICE IN THE HUSK]]> ABSTRACT This study aimed to determine the thermodynamic properties of sorption processes (desorption and adsorption) of rice in the husk, cv. Urucuia. A static-gravimetric method was used to reach equilibrium moisture content at different temperatures (10, 20, 30, 40, and 50 °C ± 1°C) and relative humidity levels (10, 30, 50, 70, and 90 % ± 2%). A decrease in moisture content led to an increment of the integral isosteric heat of sorption, indicating a higher demand for energy to remove moisture from the product. Differential entropy of sorption decreased along with a moisture content increment, with higher values for desorption. This indicates a higher mobility of water molecules during desorption if compared to adsorption. Gibbs free energy decreased with increasing temperature in both processes, with positive values for desorption (endothermic process), and negative for adsorption (exothermic process). The enthalpy-entropy compensation theory is valid for both sorption phenomena (desorption and adsorption) of rice in the husk, being both processes enthalpy controlled. <![CDATA[CLIMATOLOGICAL WATER BALANCE WITH DATA ESTIMATED BY TROPICAL RAINFALL MEASURING MISSION FOR THE DOCE RIVER BASIN]]> ABSTRACT The Climatic Water Balance (CLIMWB) is very used in the climatic characterization and can also offer important contribution in the identification of the water demand for irrigation of a region. For this, reliable precipitation data with good spatial coverage is required. The Tropical Rainfall Measuring Mission satellite -TRMM-3B43-v7 is a partnership between NASA (National Aeronautics and Space Administration) and Japan's Aerospace Exploration Agency (JAXA), which estimates rainfall data for the tropics region. The aim of this study is to evaluate the CLIMWB obtained by the Thornthwaite &amp; Mather method (1955), with estimated rainfall data with the 3B43 product versus those generated with rainfall data and to map pixel-by-pixel water availability with good spatial coverage for the Doce River basin, located in the Atlantic Hydrographic Region, Southeastern Brazil, between the states of Minas Gerais and Espírito Santo. The CLIMWB variables generated with 3B43, together with the precipitation, showed a good correlation with those fed with surface rainfall data. The largest differences between the two datasets were found in some stations in the southeast and northeast of the basin. The CLIMWB variables presented a good correlation, with the best water excess (0.94), followed by water deficit (0.88), water availability (0.84) and real evapotranspiration (0.82). With TRMM - 3B43, we can characterize the CLIMWB in a similar way to that obtained with data observed by the gauges, providing much more extensive coverage. The use of the TRMM - 3B43 precipitation data allows a consistent characterization of the regional water availability, contributing to the agricultural planning and management, mainly to fill the gaps left due to the absence of rain gauges and to possible failures in the rain gauges' data series. <![CDATA[RELATIONSHIP BETWEEN COFFEE CROP PRODUCTIVITY AND VEGETATION INDEXES DERIVED FROM OLI / LANDSAT-8 SENSOR DATA WITH AND WITHOUT TOPOGRAPHIC CORRECTION]]> ABSTRACT The reflectance values of a coffee crop are influenced by several factors such as planting direction, crop spacing, time of the year, plant age and topography which reduces the accuracy of the estimates derived from remote sensing data. In this context were evaluated the relationships between coffee productivity and values of NDVI, SAVI and NDWI vegetation indexes with and without topographic reflectance correction for different coffee phenological phases for the crop years 2013/2014 (low productivity) and 2014/2015 (high productivity). The evaluations were made through the standard deviation of vegetation indices (VIs), linear relationship between the cosine factor and the VIs and between VIs and coffee productivity. The best phenological phases of coffee to determine productivity from spectral indexes were the stages of dormancy and flowering. The results indicated that the NDVI was the best index to estimate the productivity of coffee trees with coefficient of determination (R2) that ranged from 0.58 to 0.90. There was an increase in R2 between productivity and NDVI with topographic correction in the dormancy phase in the year of low productivity; between productivity and NDVI with topographic correction in the flowering phase in the year of high productivity; and between productivity and SAVI and NDWI with topographic corrections in the flowering phase in the year of high productivity. <![CDATA[ANALYSIS OF SPATIAL AUTOCORRELATION OF GRAIN PRODUCTION AND AGRICULTURAL STORAGE IN PARANÁ]]> ABSTRACT This work aimed to study the spatial autocorrelation of the total static capacity storage, the total number of warehouses in 2013/2014 (CONAB) and the average of the total grain production (soybean, corn 1st and 2nd crops and wheat) in the harvest years 2008/2009 to 2013/2014 (SEAB) in Paraná State, Brazil. The study was based on Moran's global autocorrelation index, Moran's local and Moran's bivariate correlation. It was possible to identify regions with low and high total grain production. There was positive spatial autocorrelation for the Total Static Storage Capacity (TSSC) and Total Quantity of Warehouses (TQW). For the total grain production, significant spatial autocorrelation were found. The total static storage capacity showed similarity between the studied regions. When evaluating the bivariate spatial correlation between Total Production of Harvested Grains (TPHG) in relation to the total static storage capacity and total quantity of warehouses, the presence of positive spatial correlation was observed. The results indicated that Moran's global autocorrelation and local indexes showed significant patterns of spatial autocorrelation, as well as the bivariate spatial correlation indexes in the studied variables. <![CDATA[IMPACT OF THE HYDRAULIC LOADING RATE ON THE HYDRODYNAMIC CHARACTERISTICS OF AN ANAEROBIC FIXED BED REACTOR TREATING CATTLE SLAUGHTERHOUSE WASTEWATER]]> ABSTRACT The hydrodynamic behavior of an anaerobic fixed bed reactor (AFBR) was evaluated in the treatment of cattle slaughterhouse wastewater. The AFBR was operated at hydraulic retention time (HRT) of 14, 11 and 8 h. Stimulus-response assays were carried out with Eosin Y and the experimental data were adjusted to the single-parameter theoretical models of dispersion and N-continuous stirred tank reactors in series (N-CSTR). The experimental results of the residence time distribution curves showed that at lower flow rate, the reactor showed plug flow behavior with correlation coefficient (r) of 0.88 and number of dispersion of 0.2 for high dispersion (HD). However, at higher and intermediate flow rates, the AFBR behave as a complete mixture flow, (r) of 0.94 and 0.96, respectively. Residence time distribution curves in the AFBR showed a good approximation of the complete mixing model at hydraulic residence time of 11 and 8 h, with 5 and 2 N-CSTR reactors in series, respectively. The volume of dead zones corresponding to 43.0, 37.4 and 11.2% of the volume of the reactor for HRT of 14, 11 and 8 h, respectively, was noted, and hydraulic short circuiting were not confirmed. <![CDATA[NUTRIENT REMOVAL FROM SWINE WASTEWATER IN A COMBINED VERTICAL AND HORIZONTAL FLOW CONSTRUCTED WETLAND SYSTEM]]> ABSTRACT This study aimed to assess the performance of a combined vertical flow (VFCW) and horizontal subsurface-flow (HFCW) constructed wetland systems built on a pilot scale and submitted to different configurations and organic load application rates of pre-treated swine wastewater (SWW) in anaerobic systems on the nitrogen and phosphorus removal. The average values of redox potential in the systems were between anoxic and aerobic conditions, favoring an increased nitrate concentration in VFCW. Nitrogen removal by VFCW–HFCW system can be considered as satisfactory, reaching removal values of 75%. VFCW and HFCW proved to be limited in phosphorus removal, reaching values of 48%. <![CDATA[INFLUENCE OF SUBSTRATE AND SPECIES ARRANGEMENT OF CULTIVATED GRASSES ON THE EFFICIENCY OF HORIZONTAL SUBSURFACE FLOW CONSTRUCTED WETLANDS]]> ABSTRACT We aimed to evaluate the efficiency of six different horizontal subsurface flow constructed wetlands (HSSF-CWs), with different substrates (gravel and crushed PET bottles), which also varied in relation to the presence and arrangement of plant species (elephant grass and Tifton 85 bermudagrass) in the removal of pollutants from a bulk milk cooling tank (MTWW). Each bed was fed at a flow rate of 0.18 m3 d-1 and average organic load rate (OLR) of 318 kg ha-1 d-1 of BOD5, with hydraulic detention time (HRT) of 1.84 days in the gravel-filled HSSF-CWs (CWS-G) and 2.97 days in the PET-filled HSSF-CWs (CWs-P). The CWs-P were as efficient as the CWs-G in the removal of BOD5, COD, Total-P, and K-Total, being in some cases even more effective (turbidity, TS, TSS and Na). The gravel, on the other hand, provided greater removals of Total-N from the MTWW. In the non-cultivated CWs and those cultivated with elephant grass, in its first half and Tifton 85 grass in its second half, there were higher average efficiencies in COD and TSS removal sand, in the latter, the highest average removal of Total-N. <![CDATA[As, Cu AND Zn CONCENTRATION IN SANITARY SEWAGE SLUDGE FERTILIZED SOIL AND IN CRAMBE AND CORN GRAINS]]> ABSTRACT This study aimed to evaluate the total contents of As, Cu and Zn in the profile of a Haplic Cambisol cultivated with crambe and corn and fertilized with sanitary sewage sludge and to compare them with those obtained in other forms of fertilization, as well as the content of metals in the grain of these crops. Two experiments were carried out in the field, one with maize cultivation and another with crambe, both were delineated as randomized blocks with four treatments and six replicates, which were: without fertilization, fertilization with sewage sludge dewatered and dried in the sun, with dry sewage sludge and with mineral fertilizers. At the end of the experiments soil samples were collected at 15, 50, 100, 150 and 200 cm depth for analysis of the total contents of As, Cu and Zn, as well as the grain of the crops. No differences were observed among the treatments. The total contents of As, Cu and Zn in the soil in both experiments and in the corn grains are below the limits of prevention and the maximum limit in grains established by the Brazilian resolutions. In relation to depth, the metal contents in the samples collected from the soil submitted to the fertilization treatments were similar to those quantified in the plots that did not received fertilization, but there was accumulation of Cu and Zn in the upper layers of the soil that received fertilization. <![CDATA[DEFORMATION OF PEACHES SUBMITTED TO CYCLIC LOADING USING THE DISCRETE ELEMENT METHOD]]> ABSTRACT This study aimed to use and validate a simple contact force model that describes the behavior of peaches stored in a wooden box, loaded cyclically, by using the discrete element method. The Kelvin-Voigt contact force model was used and the cyclic loading in the simulation was performed with an amplitude of 1 mm and frequency of 12 Hz for time intervals of 3600, 5400, and 7200 s. The laboratory test was performed with a peach box attached to a vibrating table by applying the same excitation conditions used in the simulation. For validation, model results were compared with those from the laboratory test by using deformation values of fruits in the contact regions. To measure this deformation, we adapted the methodology for determining the radius of curvature. The Kelvin-Voigt linear contact model, despite its simplicity in representing the viscoelastic behavior, adequately estimated the final deformation in peaches submitted to cyclic loading. <![CDATA[TIME AVAILABLE FOR SPRAYING AND MECHANIZED SOWING IN THE NORTHEAST OF THE STATE OF MATO GROSSO DO SUL AND SOUTH OF GOIÁS]]> ABSTRACT The sizing of mechanized agricultural systems depends on the soil and climatic conditions, the crop and the work regime. The aim of this study was to determine the probabilities of time available during an agricultural year for mechanized spraying and sowing in the northeast region of the State of Mato Grosso do Sul and south of Goiás. The meteorological restrictions imposed as unfavorable hours were: ambient temperature above 32°C, relative air humidity below 50%, wind velocity above 15 km h-1 and soil volumetric moisture above 39% (humidity equivalent to 90% of the available water capacity for the studied soil). The mathematical models were elaborated for eight years, based on the historical data of the automatic station of the National Institute of Meteorology installed in the region. It was possible to determine the time available for mechanized sowing and agricultural spraying operations. The available times for every ten days of the agricultural year for mechanized spraying and sowing in the study region were determined. The hourly water balance is used for the restrictive study of soil moisture in determining the time available for mechanized operations. A single self-propelled sprayer (30 m bar) and a single seed drill (48 rows) are not sufficient to meet the operational rate in an area of 3,000 ha in the northeast of the state of Mato Grosso do Sul and south of Goiás.