Search

Soil compaction due to agricultural machinery traffic is a threat to soil productivity and soil ecological functions. The prediction of soil stresses and compaction that soil bear during the harvest and transport are fundamental indications in the prevention strategies and remediation of the soil compaction. The objective of this research was to predict soil compaction caused by harvesters and transport equipment during sugarcane harvest on soft soil. Machinery traffic was simulated using the TASC V3.0 model, Module 1 "Stress Propagation and Soil Damage" was used. The machine system used for harvest sugarcane were formed by harvesters CASE IH 8800, and tipping tows 7CX (SC)-10 pulling by tractors YTO 1608 or XTZ 150K-09. Parameters from machinery and soil are introducing as data. The use of modelling TASC V3.0 permitted to predict soil compaction caused by harvesters and transport equipment during sugarcane harvest on soft soil. More severe soil compaction was obtained during use of tipping tow 7CX (SC)-10 due to high mean contact pressure and high tire load, which caused severe soil compaction until a depth of 0.37 m. Rear tire of tractor YTO 1604 caused severe soil compaction too reaching 0.31 m of depth. In general sense all equipment caused severe soil compaction in tillage layer, therefore must be make decompactions works with the objective to loose soil in depth for a good developed of sugarcane ratoons. [ABSTRACT FROM AUTHOR]

In the present work, the vegetation indices obtained from satellite images are used to monitoring sugarcane crop. The study was carried out in 5,5 ha of sugarcane field, planted with CP 52-43 variety located in Camajuaní Municipality, Cuba. Vegetative evolution of the plantation was monitored by field measurements of leaf width, stem diameter, stem height, soil moisture and vegetal cover, using the diagonal distribution method for samples collection. The services available in Earth Observed System (EOS) were used to obtain images of vegetative index of: NDVI, SAVI, EVI and NDWI. The initial stage of crop was characterized by low values of soil moisture and foliar development of sugarcane plants, EVI and NDVI indices showed results according to the low vegetative development with values between 0,2 and 0,4, while NDWI agreed with dry soil. In the rainy season, after the fourth month of the plantation, an increase in soil moisture to 42,9% took place, the plants' biophysics parameters: stem height, stem diameter and leaf width also increased, EVI index reached between 0,6 and 0,8 in 74,4% crop area and in the same way NDVI index showed values between 0,7 to 0,8. However, NDWI index showed values between -1 and -0.6 belonging to dry soil, no matching with the actual moisture conditions. Through monitoring with Sentinel-2 satellite, a more stable representation of the increase in vegetation was achieved, as well as more adequate values of the initial and final state of the crop were obtained. [ABSTRACT FROM AUTHOR]

The objective of the present work, was to determine the main effects on the soil and in the sugar cane stumps, of mechanized activities in the plantations. It was carried out in the Basic Unit of Cooperative Production (UBPC) Máximo Gómez, belonging to the municipality of Camajuaní, Villa Clara. To carry out the research, a characterization of the study area was made; the variations of the furrow profile were determined; resistance to penetration and soil moisture in the root zone and in the street, also damage to the cane strain was identified. The main results showed agglomerations of residues from the previous harvest and clean spaces without stumps and new sprout. The resistance to soil penetration showed values of 0.8 and 1.2 kPa on surface of the street and the area of the stumps respectively, increasing with the depth of the soil up to 30 cm. Soil moisture in the stumps was higher than in the street up to 25 cm deep, with values of 28.6 and 30% respectively on the surface. For its part, the profile of the furrows showed a considerable variability in regarding the geometry and height of the ridges. Limitations were found in terms of the depth of the main roots, their vitality and quantity, the secondary or capillary roots showed low development. [ABSTRACT FROM AUTHOR]

Discrete Element Method (DEM) was used to simulate the soil-tool interaction. The model is based on the action of normal, shear, cohesion and friction forces into the cohesive granular medium, calculated as a function of micro-mechanical properties. Macro-mechanical properties of soil-soil and soil-metal were used to determining the micro parameters on the model. In order simulate the tillage operations a soil virtual block was generated in hexagonal compacted array using 45 000 spherical particles forming a cohesive block. A soil-bin installation was conditioned to measuring the draft force in hard-dry and soft-wet soil condition to compare the results with simulation tests. The comparison showed a small under predicted behavior of the model for soft-wet soil; however the results become more accurate toward hard-dry soil conditions. The density changes during simulations and pressures distributions below the tillage tool path is showed, given a dynamic representation of soil internal tension and loosening after tillage operation. [ABSTRACT FROM AUTHOR]

Specific information about physical-mechanical properties of soil is a support for simulation by computation techniques as Finite Element and Discrete Element methods to predict the soil behavior during soil tool interaction. Determination of basics mechanical properties needed for mathematical modeling of clay soils on the arable layer were carried out using triaxial compression and modified shear box test. Variations in shear strength, Yong's modulus, internal friction angle, soil-metal friction angle, cohesion and adhesion were determined at different experimental levels of gravimetric water content and soil dry bulk density. Multi-factorial regression analysis to estimate the corresponding values of above properties was performed resulting on statistical prediction equations for all basic mechanical properties under study. [ABSTRACT FROM AUTHOR]

The work was carried out in the Valle del Yabú Agricultural Company located in the municipality of Santa Clara, Villa Clara province with the objective of determining the efficiency in the use of irrigation water, in the aforementioned company, through the calculation of the productivity of the water applied to some crops of economic importance. The productivity of the water applied by irrigation, the productivity of the total water, and the total water applied (T), in the corn, potato, dasheen, beans and sweet potato crops were calculated. In the sweet potato the productivity of water applied by irrigation, 20 kg / m3, was higher than that of the rest of the crops. In the potato the average was 7.74 kg / m3, in the bean it reached values of 4.74 kg / m3, in the case of the dasheen it was 3.92 kg / m3 and the corn was 10.66 kg / m3 The results showed a low productivity and inefficiency in the use of water for potato, bean and corn crops, not the case of dasheen and sweet potato where water productivity values were obtained that show an efficient use of water in these crops. [ABSTRACT FROM AUTHOR]

The unavailability of chemical fertilizers to obtain high yields in Cuban agriculture has led to the development of other organ-mineral fertilizers, such as Agromena - G, produced by the Empresa Geominera del Centro in Villa Clara. The objective of this work was to characterize the organ-mineral fertilizer Agromena - G, based on the determination of the main physical and chemical properties of the fertilizer for its mechanized application in the improvement of soils and the increasing of crops yield. The methodology included the determination of physical properties as granulometry, apparent density and humidity of the organ-mineral fertilizer. In addition, chemical properties such as pH, electrical conductivity, available phosphorus and organic matter were determined. The physical properties of the organ-mineral fertilizer Agromena - G, show that its granulometry (approximately 50% of the grains smaller than 1 mm) favors its use since it facilitates its acquisition by the plants. The other determined properties behave within acceptable values for the most common granular fertilizers. The physical properties of this fertilizer favor its mechanized application both by broadcast fertilizing machines and with machines for localized fertilization. The chemical properties of this organ-mineral fertilizer demonstrated its potential use as an alternative for managing plant nutrition although it is recommended the surveillance of indicators as electrical conductivity and cations concentrations, especially Na+, in clayed soils susceptible to salinity problems. [ABSTRACT FROM AUTHOR]

The unavailability of chemical fertilizers to obtain high yields in Cuban agriculture has led to the development of other organic mineral fertilizers, such as Agromena - G, produced by Empresa Geominera del Centro in Villa Clara. The objective of this work was to characterize the ID-David fertilizer for the mechanized application of the Agromena - G organic mineral fertilizer produced by Empresa Geominera del Centro. The methodology included the determination of the uniformity of the transverse distribution of the fertilizer and the general characterization of the work of the fertilizer spreader. The characterization of the ID-David fertilizer spreader, fertilizer locator trailer, during the application of the Agromena - G organic mineral fertilizer showed that this machine performs reliable and stable work. The uniformity of the fertilizer application had a coefficient of variation of 15.29%, which is considered adequate for the distribution of fertilizers with high delivery doses. [ABSTRACT FROM AUTHOR]

Pruning is a very important practice to get good yields from guava tree. The present paper had as objective to examine researches accomplished on the pruning of guava tree and its influence in the yield of this fruit tree. A review was made from the available information on the topic in Cuba and abroad. Previous research evidence increments of guava production with the pruning. However, there is not a clear increasing tendency in the intensity of this practice, because the obtained results were different in terms of the cultivar investigated, plantation density, season and climate. Several authors proposed monthly pruning all the year, as well as, pruning at least three times a year. Regarding the pruning intensity, several authors agree that pruning the end of the branch can be beneficial in terms of fruit production and quality, since severe pruning reduces fruit production. However, other authors recommend the use of severe pruning for obtain higher yield. [ABSTRACT FROM AUTHOR]

The development of agricultural production requires the use of machinery to increase productivity and quality of work, a problem that is becoming more pressing in short-cycle crops (corn and beans), creating two possible scenarios, the acquisition of machinery or the improvement of the existing ones. On this last scenario, in recent years, the Ministry of Agriculture of Cuba (MINAG) has been projecting. For this reason the present work has as objective to redesign the grain seeder "Guajiro AM 2010-1-5T"for its improvement. To fulfill this objective, the machine was redesigned fundamentally for grain transmission and distribution systems, for which the resistance analysis by the finite element method (MEF) and its operation were made, through the help of the specialized softwaresMechanical Desktop 2008 and SolidWorks 2010. Later, a prototype was built which was tested in static and working conditions during the planting of corn and beans. Finally, the cost sheet was prepared and the economic feasibility of its development was determined. The main results showed that the design variant developed is capable of meeting the requirements of resistance, performance and safety necessary for these machines, in addition to meeting the quality requirements during the planting of beans and corn. The economic analysis showed the feasibility of its improvement, with an economic effectiveness of $14,340.25 (Cuban peso). [ABSTRACT FROM AUTHOR]