Matéria orgânica e propriedades físicas de um Argissolo Amarelo Coeso sob sistemas de manejo com cana-de-açúcar

Abstract

RESUMOO cultivo contínuo da cana-de-açúcar por longo tempo sob diferentes manejos em solos de tabuleiros costeiros pode causar alterações na matéria orgânica e nas propriedades físicas do solo. Estudaram-se os efeitos de diferentes sistemas de manejo com cana-de-açúcar nas propriedades de um Argissolo Amarelo Coeso, na usina Triunfo, Estado de Alagoas. Os sistemas de manejo consistiram de uma área não irrigada, uma área irrigada, uma com aplicação de vinhaça e outra sob floresta nativa, sob condição original. Amostras foram retiradas de cada área a 0-0,2, 0,2-0,4 e 0,4-0,8 m de profundidade para determinar as alterações nos limites de consistência, parâmetros de compactação, estabilidade de agregados e frações físicas da matéria orgânica do solo. O cultivo da cana-de-açúcar sob os sistemas sequeiro e irrigado promoveu redução mais expressiva no limite de plasticidade, umidade ótima de compactação e diâmetro médio ponderado dos agregados, em relação ao solo sob mata nativa, devido à maior redução nos teores de carbono orgânico total e matéria orgânica particulada do solo. O sistema de manejo com aplicação de vinhaça promoveu menor degradação nas propriedades físicas e químicas do solo, em relação ao solo sob mata nativa.Palavras-chave: matéria orgânica particulada, compactação do solo, ensaio Proctor normal, tabuleiros costeiros Organic matter and physical properties of a Cohesive Yellow Argisol under different management systems with sugar cane ABSTRACTThe continuous cultivation of the sugar cane for long-term under different management systems in soils of Coastal Tablelands can cause alterations in the organic matter and in the physical properties of the soil. The effects of different management systems with sugar cane on the properties of a Cohesive Yellow Argisol, in the Triunfo Sugar Cane Mill, in the State of Alagoas, Brazil, were studied. The management systems consisted of an irrigated area, an area not irrigated, an area with vinasse application and an area under native forest in original condition. Samples were collected from each area at 0-0.2, 0.2-0.4 and 0.4-0.8 m depths to determine the modification in the consistence limits, compaction parameters, stability of aggregates and physical fractions of the organic matter of the soil. The results indicated that the cultivation of sugar cane under not irrigated and irrigated systems promoted a more expressive reduction in the plasticity limit, optimum moisture for compaction and aggregate mean weight diameter, in relation to soil under native forest, due to reduction in the contents of total organic carbon and of particulate organic matter. The management system with vinasse application promoted smaller degradation in physical and chemical properties of the soil in relation to soil under native forest.

Carbon fractions and soil fertility affected by tillage and sugarcane residue management an Xanthic Udult

“…These findings are completely contrary to those reported by Silva et al (2006) in an Argissolo Amarelo coeso, a common soil in coastal tableland environment. The authors reported that 25 years of cultivation with soil tillage, using disking operations in the renovation of cane fields and burning sugarcane before harvesting, caused reduction in the carbon content of POM and MOM in the layer of 0-0.2 m. These negatives effects indicate the importance of residue retention and reduction of tillage for soil carbon storage, and reinforce the importance of fractions of the organic matter to assess soil management practices.…”

Physical attributes of ultisol of Brazil's northeastern semiarid under organic farming of wine grapes

“…By comparing this value with the MWD obtained in the second evaluation, it was possible to verify that Ultisol showed values higher than 0.5mm for both cultivated and fallow areas, which makes the latter be considered relatively resistant to crumbling and dispersion. Silva et al (2006) evaluated the distribution of classes of aggregates obtained by a wet processing of cohesive Ultisol cultivated with sugarcane and observed the decrease of aggregates larger diameter (> 2.00 mm and 2-1 mm) in the 0.00 to 0.20m and 0.20 to 0.40m layers. The GMD showed the highest values for fallow area, although did not differ significantly when only the soil sample depth was considered, and there was no significant interaction between sampling sites and depths (Table IV).…”

Soil attributes under agroecosystems and forest vegetation in the coastal tablelands of northestern Brazil

“…Those contents are common for coastal tableland soils, and may vary upwards in soils under forest (SILVA et al, 2006b) and downwards in soils under agricultural use (FERNANDES et al, 2011;PACHECO;CANTALICE, 2011). The V values in the 0-20 cm layer presented an overall average of 62%, with only the RF group presenting low content (33%).…”

“…The POM and DOC content also contributed to this, but to a lesser degree. In other words, if WSA variations are sensitive to use and management (VASCONCELOS et al, 2010) and they present significant and positive correlation with OC (SILVA et al, 2006b), its extreme dependence on the texture hinders the comparison of data for coastal tableland soils, so varied in texture. …”

“…The decrease of the coastal tableland soil quality after the substitution of the forest by agricultural use, considering quantifications of its superficial and subsuperficial horizons, has been reported in specific studies, with obvious effects on the organic matter pools and associated variables (cation exchange capacity, water stable aggregates and average aggregate diameter) (SILVA et al, 2006a;SILVA et al, 2006b;COSTA et al, 2009;SANT'ANNA et al, 2009;FERNANDES et al, 2011;PACHECO;CANTALICE, 2011), however there is a lack of studies including a wider geographical sampling.…”