5 results

Temporal Variation of Soil Physical Quality under Conventional and No-Till Systems

Carlos Germán Soracco, Luis Alberto Lozano, Rafael Villarreal, Esteban Melani, Guillermo Oliverio Sarli

04/Apr/2018

ABSTRACT: Determination of soil physical quality (SPQ) is very important because it is related to many important soil processes. However, it is not clear which indicators should be considered in this evaluation, and information about temporal variation of SPQ under different soil tillage systems is scarce. The aim of this study was to determine the effects of no tillage (NT) and conventional tillage (CT) on temporal variation of capacity SPQ indicators [bulk density (BD), macroporosity (Pmac), air capacity (AC), plant […]

Quantitative Assessment of Soil Physical Quality in Northern China Based on S-theory

Dejun Yang, Zhengfu Bian, Kefeng Zhang, Jibing Xiong, Shaogang Lei

01/Sep/2015

ABSTRACT Quantitative assessment of soil physical quality is of great importance for eco-environmental pollution and soil quality studies. In this paper, based on the S-theory, data from 16 collection sites in the Haihe River Basin in northern China were used, and the effects of soil particle size distribution and bulk density on three important indices of the S-theory were investigated on a regional scale. The relationships between unsaturated hydraulic conductivity Ki at the inflection point and S values (S/hi) were […]

Soil functioning in a toposequence under rainforest in São Paulo, Brazil

Miguel Cooper, João Carlos Medeiros, Jaqueline Dalla Rosa, José Eduardo Soria, Raul Shiso Toma

01/Apr/2013

Studies of soil-water dynamics using toposequences are essential to improve the understanding of soil-water-vegetation relationships. This study assessed the hydro-physical and morphological characteristics of soils of Atlantic Rainforest in the Parque Estadual de Carlos Botelho, state of São Paulo, Brazil. The study area of 10.24 ha (320 x 320 m) was covered by dense tropical rainforest (Atlantic Rainforest). Based on soil maps and topographic maps of the area, a representative transect of the soil in this plot was chosen and […]

Pedotransfer functions to estimate water retention parameters of soils in northeastern Brazil

Alexandre Hugo Cezar Barros, Quirijn de Jong van Lier, Aline de Holanda Nunes Maia, Fábio Vale Scarpare

01/Apr/2013

Pedotransfer functions (PTF) were developed to estimate the parameters (α, n, θr and θs) of the van Genuchten model (1980) to describe soil water retention curves. The data came from various sources, mainly from studies conducted by universities in Northeast Brazil, by the Brazilian Agricultural Research Corporation (Embrapa) and by a corporation for the development of the São Francisco and Parnaíba river basins (Codevasf), totaling 786 retention curves, which were divided into two data sets: 85 % for the development […]

Pedotransfer functions for the soil water retention and soil resistance to penetration curves

Álvaro Pires da Silva, Cássio Antonio Tormena, Jonez Fidalski, Silvia Imhoff

01/Feb/2008

Pedotransfer functions (PTFs) are useful tools to obtain estimates of soil physical properties such as the soil water retention curve (SWRC) and the soil resistance to penetration curve (SRPC), which are important inherent soil properties and difficult to measure. Most of the studies in the literature report PTFs only in relation to SWRC estimates. An important and necessary advance in this research area would be the development of PTFs for a simultaneous estimation of the SWRC and SRPC, which is […]