Qualidade física de solos sob pastagens submetidas a reflorestamentos em épocas distintas: Pinheiral-RJ

• Autor(a) principal: Rodrigues, Rulian Pessoa
• Data de Publicação: 2021
• Outros Autores: [e-mail]
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/17367
• topic: Land degradation; Soil physical properties; Reforestation; Degradação das terras; Propriedades físicas dos solos; Reflorestamento – Rio de Janeiro (Estado); Geografia humana – Solos – Rio de Janeiro (RJ); Solos – Propriedades físicas – Pinheiral (RJ); Solos – Degradação – Pinheiral (RJ); Degradação ambiental – Aspectos socioeconômicos; Pastagens – Manejo; CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOGRAFIA FISICA::GEOECOLOGIA

The land degradation of a given geographical space is related to the history of its human occupation and the forms of use to which it is and has been subjected. In the region of the middle valley of the Paraíba do Sul River, the way coffee plantations were introduced resulted in the destruction of much of the Atlantic Forest. The "uphill" plantations and the lack of conservation practices accelerated the process of physical-chemical degradation of the soils, causing coffee producers to deforest even more areas in search of expanding the planting areas and maintaining profits. This work aimed to contribute to the understanding of the influence of different forms of land use and occupation in this region, such as pastures and areas submitted to reforestation at different times, on the physical quality of the soils, using the area of the land as a spatial cutout. Pinheiral Campus of the Federal Institute of Rio de Janeiro - IFRJ. Soil morphological aspects were identified in different sub-areas at two depths, with particle size analysis, particle density, soil density total porosity, organic matter content, carbon stocks and aggregate stability. Degraded pastures, despite representing an unsustainable environment, showed soils with good physical quality, although showing some signs of compaction, and this was evidenced by the high levels of organic matter, showing that the pastures have high biomass production, enabling the formation of aggregates with greater weighted and geometric mean diameters. In the burnt pastures there was a reduction in the contents of organic matter and in the values of aggregation indexes. 5-year reforestations showed intermediate-quality soils considering pasture areas and the oldest reforestations. The reforestation of 20 years showed soils with better physical quality, with a morphology, characterized by structure in subangular to lumpy blocks and favored by high levels of organic matter, which provided lower values of apparent density and higher rates of aggregation. Statistical analyzes through the Tukey test showed that the values of organic matter contents, especially at depths of 0-10 cm, were higher in reforestation for 20 years, although there is no difference in relation to aggregation rates. The results of the dissertation allowed to conclude that: the reforestation evaluated in its most advanced stages had a positive influence on the physical quality of the soils, providing soils with high levels of organic matter and aggregation indexes; such practices, since they reflect on the control of erosion, on the return of the original ecosystems and environmental services linked to previously degraded areas.