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Search Results: 1 - 10 of 15060 matches for " soil compaction "
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Soil compaction and arbuscular mycorrhizae affect seedling growth of three grasses  [PDF]
Mark Thorne, Landon Rhodes, John Cardina
Open Journal of Ecology (OJE) , 2013, DOI: 10.4236/oje.2013.37052
Abstract:

Soil compaction is a limitation to establishment of native forest species on reclaimed surfacemined lands in Appalachia. Previously, non-native forage species such as tall fescue (Schedonorus arundinaceus(Schreb.) Dumort., nom. cons.) have been planted because they easily established on reclaimed mine soil. There is now interest in establishing robust native prairie species to enhance biodiversity and provide greater potential for root activity in the compacted soil. We conducted a 10-week glasshouse study comparing growth of “Pete” eastern gamagrass (Tripsacum dactyloidesL.), “Bison” big bluestem (Andropogon gerardiiVitman), and “Jesup MaxQ” tall fescue at soil bulk densities (BD) of 1.0, 1.3, and 1.5 g·cm-3. We also examined effects of arbuscular-mycorrhizal fungi (AMF) on plant growthin relation to compaction. Sources of AMF were a reclaimed surface coal mine soil and a native tallgrass prairie soil. Shoot and root biomass of tall fescue and big bluestem were reduced at 1.5 BD while eastern gamagrass growth was not affected. Growth ofbig bluestem and eastern gamagrass was greaterwith AMF than without, butsimilar between AMF sources. Tall fescue growthwas not enhanced by AMF. Overall, tall fescue biomass was 3 times greater than eastern gamagrass and 6 times greater than big bluestem when comparing only AMF-colonized grasses. Eastern gamagrass and big bluestem are both slower to establish than tall fescue. Eastern gamagrass appears to be more tolerant of compaction, while big bluestem appears somewhat less tolerant.


Energy Analysis for the Compaction of Jerash Cohesive Soil  [PDF]
Talal Masoud, Hesham Alsharie, Ahmad Qasaimeh
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2015, DOI: 10.4236/cweee.2015.41001
Abstract: The aim of this research is to study the effect of compaction energy on Jerash cohesive soil. Qualitative and quantitative analyses of soil compaction energy with relation to unit weight and moisture content are conducted. These analyses spot the light on energy savings performed for soil compaction. The study shows that as the compaction energy increases; the unit weight of the Jerash cohesive soil increases and the optimum water content decreases. Generally, a soil with low moisture content is less vulnerable to compaction than a soil with high moisture content. But when the moisture content is too high, all the soil pores are filled with water, so that the soil becomes less compressible where the unit weight and strength characteristics decrease. The optimum energy value and optimum water content are thus of great concern. The effect of energy on soil unit weight is very large as the energy increases from 400 to 1400 KJ/m3 and after that level; the effect of energy on soil unit weight is very small. Consequently, optimal compaction energy ranges from 1200 up to value 1400 KJ/m3, where 50 to 60 blows can be applied and the optimal correlated water content is between 14% - 15%.
Headwaters Deforestation for Cattle Pastures in the Andes of Colombia and Its Implications for Soils Properties and Hydrological Dynamic  [PDF]
Guillermo Vásquez-Velásquez
Open Journal of Forestry (OJF) , 2016, DOI: 10.4236/ojf.2016.65027
Abstract: Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands have been intended mainly to pasture cattle. Soil compaction, caused by the trampling of cattle, was evaluated in soils derived from volcanic ash (Andisols), with reference to values found for variables in undisturbed natural forests in the same region. The compared parameters were bulk density (Db), total porosity (α), soil resistance to penetration (Rp) and pore size distribution, analyzed by water retention curves (WRC). The grazed soils had significant differences with respect to the natural forest reference values: Db was 53.7% higher, α was reduced by 11.0% and Rp in the first 7.5 cm of the top soil was more than double, with an average increase of 275.2 to 527.2 kPa. The analysis indicated that compacted soils had relatively uniform reduction in distribution of macro, meso and micropores. It was concluded that deforestation followed by pasture land destination in steep headwaters generates significant compaction processes that can affect the infiltration, percolation and soil water storage, which would have important hydrological implications: augmentation of surface runoff and soil erosion, decreased the base flow and increased direct runoff. For this reasons, it is considered that forest restoration of headwaters is important for the maintenance of hydrological functions of large river systems.
Comparison of Five Tillage Systems in Coastal Plain Soils for Cotton Production  [PDF]
Ahmad Khalilian, Michael A. Jones, Philip J. Bauer, Michael W. Marshall
Open Journal of Soil Science (OJSS) , 2017, DOI: 10.4236/ojss.2017.710018
Abstract: Soil compaction management in the southeastern USA typically relies heavily on the practice of annual deep tillage. Strip tillage systems have shown considerable promise for reducing energy and labor requirements, equipment costs, soil erosion, and cotton plant damage from blowing sand. Replicated field trials were conducted for three years in South Carolina, to compare the performance of three different strip tillage systems to conventional tillage and no-till methods. A second objective was to investigate whether the frequency of deep tillage can be reduced by planting cotton directly using controlled wheel traffic into the previous year’s subsoiler furrow. Tillage treatments included: conventional tillage (disk-subsoil-bed), straight shank strip-till, bent-leg shank strip-till (Paratill), bent-leg shank strip till (Terra Max), and no-till. Deep tillage was performed in all plots the first year. In years two and three, the plots were split and half received annual deep tillage and the other half were not deep tilled either year. Tillage methods were compared side by side with and without irrigation. Deep tillage reduced soil compaction and increased taproot length and cotton yields than the no-till system. There was no difference in cotton lint yield between the strip-till systems and conventional tillage in either dry land or irrigated plots. Deep tillage increased cotton lint yields compared to no-till. There was no difference in lint yield between plots which were deep-tilled in all three years with those which had tillage operation only in first year of the test. Dry matter partitioning at first bloom was reduced in plant height, total dry weight, and leaf area in strip-till and no-till production systems compared to the conventional tillage system. The results suggest that all three strip tillage systems are equally effective for cotton production and that annual deep tillage is not necessary if controlled traffic is employed.
Growth and Development Responses of Tobacco (Nicotiana tabacum L.) to Changes in Physical and Hydrological Soil Properties Due to Minimum Tillage  [PDF]
Francesca Orlando, Marco Napoli, Anna Dalla Marta, Francesca Natali, Marco Mancini, Camillo Zanchi, Simone Orlandini
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.23038
Abstract: Minimum tillage is a soil conservation practice involving a reduction in soil disturbance and topsoil compaction, which could minimize environmental impact of the tobacco cultivation system. The objectives of this study were to evaluate the development and growth responses of Nicotiana tabacum and the changes in the physical and hydrological soil properties after the application of two different treatments: minimum tillage (MT) and conventional tillage (CT). MT did not cause any pronounced differences in the crop yield compared to CT, instead it positively affected the physical and hydrological soil properties and the plants’ vegetative growth. Under MT, the soil showed a higher structural stability than CT with significantly lower compaction values. With MT the soil showed a higher capacity to maintain and store water during the drought periods, evidenced by soil moisture values significantly higher than CT. Tobacco on MT showed a good response, significantly prolonging the vegetative growth stage which at harvest determined a higher stem height, greater number of leaves and longer internodes.
Effect of Compaction on Physical and Micromorphological Properties of Forest Soils  [PDF]
Iraj Bagheri, Samira Bahram Kalhori, Mehdi Akef, Farhad Khormali
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.31018
Abstract: The objective of this research was to assess the effect of skidding machinery on soil physical and micromorphological properties. The different positions (control or non-traffic areas, left wheel track, right wheel track and log track) and two soil depths (0 - 10 and 10 - 20 cm) in three repetitions were investigated. The results showed that average soil dry bulk density in four positions and two soil depths were significantly different. Comparison of average total porosity percentage and soil saturated hydraulic conductivity revealed that there were significant differences in four positions and two soil depths. Soil thin section studies using Image Tool software showed that in compacted samples there was an increase in the number of vughs voids and channels voids were in low occurrence. Micromorphological studies showed that soil compaction caused void size to decrease. In compacted samples voids bigger than 10 μm were very rare and dominant voids size was 2 μm. In compacted samples soil structure were damaged and aggregates were compressed. Also soil matrix was compressed and microstructure was massive. Results from this study confirmed that skidding machinery had a significant effect on soil physical and morphological properties. These changes causes soil and environmental degradation due to reduction in water infiltration increasing soil erosion risk.
Influence of Tillage and Deep Rooted Cool Season Cover Crops on Soil Properties, Pests, and Yield Responses in Cotton  [PDF]
Michael W. Marshall, Phillip Williams, Ali Mirzakhani Nafchi, Joe Mario Maja, Jose Payero, John Mueller, Ahmad Khalilian
Open Journal of Soil Science (OJSS) , 2016, DOI: 10.4236/ojss.2016.610015
Abstract: Soil compaction is a significant problem in the Southeastern USA. This compacted zone or hardpan limits root penetration below this layer and reduces potential yield and makes plants more susceptible to drought induced stresses. Soil compaction in this region is managed using costly annual deep tillage at or before planting and there is a great interest in reducing and/or eliminating annual tillage operations to lower production costs. Deep rooted cool season cover crops can penetrate this compacted soil zone and create channels, which cash crop roots, such as cotton, could follow to capture moisture and nutrients stored in the subsoil. The cool season cover crop roots would reduce the need for annual deep tillage prior to planting, increases soil organic matter, which provides greater water infiltration and available water holding capacity. Field studies were conducted for two years with three different soil series to determine the effects of tillage systems and cool season cover crops on the soil chemical and physical properties, yield responses, and pest pressure. Results showed that cool season cover crops significantly reduced soil compaction, increased cotton lint yield and soil moisture content, reduced nematode population densities, and increased soil available P, K, Mn, and organic matter content compared to the conventional no-cover crop.
Resistência mecanica do solo e for?a de tra??o em hastes sulcadoras de semeadoras-adubadoras em sistema de integra??o lavoura-pecuária
Conte, Osmar;Levien, Renato;Trein, Carlor R.;Mazurana, Michael;Debiasi, Henrique;
Engenharia Agrícola , 2008, DOI: 10.1590/S0100-69162008000400013
Abstract: the use of crop-livestock integration systems, with forage implantation during winter and corn or soybean sown during summer, has become an alternative to activity diversification while magnifying profits. cattle grazing, mainly in agricultural areas under no-tillage, can result in additional soil compaction, which can usually be diagnosed by increases in soil resistance to penetration (rp). aiming to evaluate the correlation between rp and traction force (ft) measured with cutting shafts, in the years of 2004 and 2005, an experiment was conducted in s?o miguel das miss?es - rs, brazil, in an oxisoil (0.540 kg kg-1 clay content). treatments consisted of four grazing intensities, which resulted in pasture heights of 10; 20; 30 and 40 cm, and a no-grazed area used as blank, designed in randomized blocks with three replicates. after the grazing period and during soybean sowing, rp was evaluated; also, required power to openers chisel type coulter was measured. both parameters increased with increments in grazing intensity. there was correlation between both parameters, showing that it is possible to evaluate the condition of soil′s compaction by measuring draft requirement by fertilizer furrow openers.
Uso do penetr?metro eletr?nico na avalia??o da resistência do solo cultivado com cana-de-a?ucar
Iaia, Antonio M.;Maia, Jo?o C. S.;Kim, Michely E.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2006, DOI: 10.1590/S1415-43662006000200038
Abstract: this work aimed to evaluate soil resistance to penetration by means of a constant-speed electronic penetrograph, in two soils: a clay-textured rhodic haplustox and a loamy-textured typic haplustox, under mechanization and transportation processes in a sugarcane crop as a function of different numbers of cuts and different working depths. the data were statistically analyzed under two formats: (a) by means of conventional statistics, in which the treatment means were compared by tukey test at 5% probability level, and (b) by geostatistical analysis, in which semivariance was used to produce models that would represent the spatial dependence of the data. the resistance to penetration results showed distinct behaviors for the studied depths, indicating that the weight of vehicles and machinery and the rotating wheel pressure caused alterations in the soil profile.
Compacta??o de um latossolo vermelho causada pelo tráfego do "forwarder"
Fernandes, Haroldo Carlos;Souza, Amaury Paulo de;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000300002
Abstract: mechanization is a powerful tool in the agro-forest industry, today, playing an important role in the processes of forest production, exploration and transportation. however, this intensive machinery utilization can cause severe damages to the soil, especially compaction, which can have a negative reflection on productivity. the main objective of this research was to evaluate the effects of soil compaction caused by forwarder traffic. the soil physical parameters analyzed were: soil density and soil penetration resistance, with the soil samples being taken at five sampling points, equally spaced along the exploration track, at three depth levels (0-15 cm, 1530 cm and 30-50 cm). each variable was analyzed by variance analysis, applied in split plots with the following effects being evaluated: machine, depth, and machine-depth interaction. the result analysis showed that the forwarder caused a small soil compaction i.e., an average increase close to 0.06 g/cm3 in soil density and 1.00 mpa in soil penetration resistance. the maximum values of soil density and penetration resistance after machine traffic were, respectively, 1,12 g/cm3 and 2,87 mpa.
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