Search

The objective of this work was to evaluate the effects of different types of soil use, on organic carbon reserves, in a Chromic Vertisol. At a Permanent Observation Point, located in the town of Guaro, Mayarí municipality, Holguín province. Soil samples were taken at the depth of 0-20 cm, in three Land Use Types (LUT), Neem Forest, Natural Pasture and Sugarcane. Total organic carbon and its organic fractions, coarse and fine particulate carbon and that associated with minerals were determined after the granulometric physical fractionation of the samples. The highest carbon reserves were found in the Neem Forest and Natural Pasture LUT in a period of 12 years after the reconversion, of 67,60 and 80,20%, respectively, with respect to the Sugar Cane LUT. The organic fractions were significantly favored in the Neem Forest and Natural Pasture LUTs with respect to the Sugar Cane LUT. [ABSTRACT FROM AUTHOR]

The study was carried out in the soil physics laboratory of the Agricultural Engineering Research Institute (IAgric) with the purpose of knowing how the hydro physical properties of a compacted Red Ferralitic soil vary in the presence of different doses of super absorbent polymers. Soil from the IAgric Experimental Station and water from the well located in that station were used. Doses of 20, 30 and 40 g of polymer per kilogram of soil were tested for the tests which were compared with a control without polymers. The tests performed were: obtaining the tension-humidity curve by the sandbox method, determination of humidity by the gravimetric method and texture by the Boyucos method. In all samples, the water storage capacity of the soil was evaluated, the behavior of the tension-humidity curve and the texture of the soil once the polymer was applied were evaluated. The results obtained show that the water retention capacity of the soil increased with the increase in the doses of hydrogel applied with respect to the soil without this polymer; increasing retention capacity up to 96,6% with the highest polymer dose. The soil moisture test was effective since for each gram of polymer added, 0,013g of water was obtained in the soil. The results obtained allow us to conclude that the application of the polymer is effective in influencing the increase in the water storage capacity in the soil. [ABSTRACT FROM AUTHOR]

The main objective of this work is to model the effect of the change of the physical properties and hydric behavior in a clay soil and the available water for plants using a simulation tool validated for these conditions. The soil and climate reference data were generated in previous studies in the Experimental Station of the Institute of Agricultural Engineering (IAgric), located in Alquízar, in Artemisa province, where soil is classified as Red Ferralitic and the climatic characterization used was from 1985 to 2010. It was used the MACRO model that constitute a mechanistic model of water and solute transport previously validated for this soil and climatic conditions. It was used the model option for estimate hydraulic properties of the soil using pedotransfer functions to estimate variations in these properties starting from variations in bulk density in upper soil layers (0-40 cm). The results show the decrease of bulk density in 0,1 g.cm-3 in studied soil layers may produce an increase in water retention capacity until 15% and can produce a decrease in water needs between 30 to 20% for dry period and between 90 to 35 % in wet period, increasing soil infiltration capacity about 30% with a more slow redistribution process. [ABSTRACT FROM AUTHOR]

The use of conservationist technologies is an alternative to mitigate the problems related to the degradation of soils, caused by the intensive use of agricultural machinery. Based on this principle, in the present work an investigation of two systems of soil tillage (traditional and conservationist) is carried out in order to determine the influence of these on some physical properties of soils. The research was carried out in a compacted red ferralitic soil from the experimental area of t he Institute of Agricultural Engineering located in the Alquizar municipality in bean, corn and sweet potato crops. An experimental design was used in a simple plot for the evaluation of the variables apparent density, gravimetric humidity and resistance to penetration in the studied crops. As a result, it was obtained that in traditional and conservation tillage systems the apparent density, at the beginning and end of the research period, decreased by 0.33 and 29%, the resistance to penetration increased by 9.67 kg / cm2 with respect to the initial value obtained, while in conservation tillage the decrease was 13.26 kg / cm². All these results demonstrate the favorable effect of conservation tillage on the soil compared to traditional tillage technology. [ABSTRACT FROM AUTHOR]

Soil tillage induced soil´s compactation, reduce soil porosity, increase bulk density and as consequences, reduced soil´s infiltration capacity. In order to study the effect of two soil´s tillage methods in soil´s infiltration capacity, was carry out this work in a ferralitic red soil on the Agricultural Engineering Research Institute Experimental Station where there is under trials two tillage system; soil tillage using arrow plow and tiller (PM) and conventional tillage with mouldboard and disc ploughs (PC); in both plot were determined the soil infiltration using infiltrometers rings (three repetitions in each plot), soil water content was determined before the infiltration test and immediately and 24 hours after the test, were it was determined also soil bulk density, infiltration equations for each ring were determined using Kostiakov´s equation.Until 30 cm soil depth, soil bulk density (Bd) in treatment PM was lower than in PC, but at 40 cm soil Bd values were similar, in both cases the Bd values obtained were higher than typical values reported for this soils; Kostiakov´s equation parameters K and n from accumulated soil infiltration in PM (K =8,54, n= 0,788) and PC (K =7.49, n= 0,644) were significatively different (pË‚ 0.05), basic infiltration values were 0.56 and 0.43 mm min-1 for PM and PC respectively. The results showing the posibilities for increase water use efficiencies through the increase in soil infiltration changing the traditional soil´s working system to less soil´s intervention system. [ABSTRACT FROM AUTHOR]

The research was carried out during sugar cane harvest season 2014 to 2015 in the Basic Unit of Cooperative Production (UBPC) Carlos Perera, of the UEB Héctor Rodríguez, Villa Clara province, Cuba, with the objective of determining the compaction and variation of the bank profile caused by the harvester's traffic CASE IH A8800 on wet soils. It was determined penetration resistance, bulk density and variation of bank profile, before and after of harvester traffic, on soils with 60.8% of moisture content. The harvester caused an increment of the penetration resistance of 12.5% and a maximum increment of bulk density of 8.9%. The bulk density of ≈ 1 g/cm3 after the harvester traffic, it was far from of the value of 1.15 g/cm3 considered as soil compaction threshold starting from which the plants growth is affected, in the type of researched soil. The variation of bank profile was only of about 5 cm in the ends proving that tracked machines are appropriate for harvest in wet soils. The scarce soil affectation provoked by this machine make it appropriate for its use during harvest in wet soil (≥ 50%). [ABSTRACT FROM AUTHOR]