Using splines in the application of the instantaneous profile method for the hydrodynamic characterization of a tropical agricultural Vertisol
06/abr/2022
ABSTRACT An important aspect in the study and understanding of the physical phenomena involved in water movement in the soil-plant system is the need to carry out the hydrodynamic characterization (HC) of non-saturated field soils. Studies of this type have been widely developed in soils of temperate climates, but they are infrequent in the tropics, hence there is a need for further research in tropical Vertisols under field conditions. Hydrodynamic characterization consists of finding the functional relationship between soil hydraulic […]
Estimation of the Retention and Availability of Water in Soils of the State of Santa Catarina
02/nov/2018
ABSTRACT: Soil water retention and availability are important properties for agricultural production, which can be measured directly or estimated by pedotransfer functions. Some studies on this topic were carried out in Santa Catarina, Brazil. To improve the estimates, it is necessary to evaluate other properties, to analyze more soil types, as well as to use other analysis techniques such as artificial neural networks and regression trees. Thus, the objective of the study was to estimate the field capacity (FC), permanent […]
Bulk Density Prediction for Histosols and Soil Horizons with High Organic Matter Content
09/mar/2017
ABSTRACT Bulk density (Bd) can easily be predicted from other data using pedotransfer functions (PTF). The present study developed two PTFs (PTF1 and PTF2) for Bd prediction in Brazilian organic soils and horizons and compared their performance with nine previously published equations. Samples of 280 organic soil horizons used to develop PTFs and containing at least 80 g kg-1 total carbon content (TOC) were obtained from different regions of Brazil. The multiple linear stepwise regression technique was applied to validate […]
Intervalo hídrico ótimo na avaliação de sistemas de pastejo contínuo e rotacionado
01/jun/2004
A qualidade física do solo sob sistemas de pastejo contínuo e rotacionado foi avaliada pelo Intervalo Hídrico Ótimo (IHO). A amostragem foi realizada na área experimental da Embrapa Gado de Corte. Foi estudado um Latossolo Vermelho distrófico. Foram avaliados quatro piquetes, sendo dois no sistema de pastejo contínuo e dois no sistema de pastejo rotacionado. No sistema de pastejo contínuo, implementado com a espécie Brachiaria decumbens cv. Basilisk, foram retiradas 30 amostras por piquete, não tendo um dos piquetes recebido […]
Incorporação da densidade no ajuste de dois modelos à curva de retenção de água no solo
01/jun/2002
A curva de retenção de água no solo é fundamental para o desenvolvimento de estudos relacionados com a dinâmica da água, com a modelagem de processos físicos do solo e crescimento das plantas. Normalmente, a curva de retenção é obtida por meio de medidas simultâneas do conteúdo de água (θ) e do potencial mátrico da água no solo (ψ) numa única amostra. Um procedimento alternativo consiste em utilizar várias amostras por ψ para descrever a curva de retenção. A utilização […]