ABSTRACT
This data article provides high spatial resolution (1 cm) datasets and related figures of the penetrometer resistance (PR) and soil bulk density (BD) data of nine agricultural 50 × 160 cm soil profiles exposed to three tillage treatments and including a wheel track. Soil treatments are moldboard plowing (MP), deep loosening (DL), and minimum tillage (MT). It also provides bulk density data, soil moisture content at various suctions and the parameters of van Genuchten's model for 27 soil cores, and saturated hydraulic conductivity (Ks) of 49 soil cores. Both sample sets were sampled to cover the profile heterogeneity in two agricultural plots subjected to moldboard plowing and minimum tillage. Examples of reuse potential include (i) the use of these spatially explicit data in studies seeking to understand better and integrate the effect of treatment and machine traffic-induced soil structure in soil hydraulic and soil physical quality, and (ii) the development of pedotransfer functions with data incorporating the soil structural heterogeneity. This Data in Brief article complements the companion paper by Alonso et al. (2021) "A hybrid method for characterizing tillage-induced soil physical quality at the profile scale with fine spatial detail" in Soil and Tillage Research[1].
ABSTRACT
Most of the soil quality assessment protocols are focused on crop production and conservation management, while studies on vital soil functions, such as water recharge potential, should be incorporated into the monitoring of impacts on environmental quality. Our objective was to evaluate, through the Nexus approach, how dynamic (land use and management) and inherent (soil type) factors impact soil physical properties and processes that drive water recharge potential, biomass production, and water erosion in the Cantareira System, Brazil. The assessment considered three soils (Typic Hapludult, Typic Dystrudept, and Typic Usthortent) and four land uses (native forest, rotational grazing, extensive grazing, and eucalyptus), which constitute the main soils and land uses in the Cantareira System region. Representative soil samples were collected at 0-5 and 30-35 cm depth and analyzed for several soil physical quality indicators, which were used to calculate a Soil Physical Quality Index based on soil functions. Converting the native forest to eucalyptus and pasture reduced the overall soil physical quality and water recharge potential. The groundwater recharge potential function in the topsoil has the highest score of 0.72 for Typic Dystrudept in native forest contrasting with 0.16 for extensive pasture. Typic Dystrudept obtained the highest value of the SPQI value (0-5 cm: 0.85; 30-35 cm: 0.90) for native forests when compared to Typic Hapludult (0-5 cm: 0.76; 30-35 cm: 0.57) and Typic Usthortent (0-5 cm: 0.75; 30-35 cm: 0.72). Our findings sustain that land use effects on soil functions depends on soil type. Inclusion of soil type into the Nexus approach increases the understanding of natural resources and derived benefits of water, energy and food in the Cantareira System.
ABSTRACT
O aumento da demanda pela avaliação da qualidade da estrutura do solo para o adequado crescimento de plantas tem motivado pesquisadores a desenvolverem técnicas visuais de avaliação, a campo, simples e confiáveis para esse fim. No Brasil, um número reduzido de estudos foi realizado empregando métodos visuais de diagnóstico do estado estrutural de solos no campo. Esse trabalho testou a hipótese de que o método de Avaliação Visual da Qualidade da Estrutura do Solo desenvolvido por BALL et al. (2007) para solos de clima temperado pode ser aplicado na identificação de campo da qualidade estrutural de um Latossolo Vermelho Distroférrico sob diferentes sistemas de uso e manejo. Para isso, foram avaliadas amostras indeformadas coletadas de mata preservada (M), sistema de integração lavoura-pecuária (ILP) e sistema plantio direto (SPD). A avaliação da estrutura apoiou-se na aparência, na resistência e nas características das unidades estruturais de blocos de solo e foi definida por cinco escores visuais de classificação de qualidade. O método empregado permitiu distinguir a qualidade do solo de diferentes sistemas de uso e manejo a partir da avaliação da estrutura da camada estudada.
The increasing demand for assessing soil structure for crop growth has motivated researchers to develop simple and reliable visual indicators to assess soil structure at the field. There are a few records in Brazil indicating the use of visual techniques for assessing soil physical quality. This paper tested the hypothesis that the Visual Soil Structure Quality Assessment methodology developed by BALL et al. (2007) is reliable for identifying the structural quality of tropical and subtropical soils under different soil management systems. Therefore, the overall objective of this paper was to visually identify the structural quality of an Oxisol under forest, crop-livestock rotation and no-till system. The structure evaluation was based on appearance, strength and characteristics of structural units from soil blocks, and was defined by five visual scores from the classification quality. The method allows distinguishing soil quality of the different soil use and management systems from the evaluation of the layer sampled.
