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Information on the quantitative tillage effects on pore space and near‐saturated hydraulic characteristics is important to improve decision support systems for soil and environmental management. The purpose of this study was to determine the effect of conventional (CT) and reduced tillage (RT) on water retention and infiltration properties of an Agrudalf sandy loam surface soil under long‐term winter wheat (Triticum aestivum L.) cropping. Using tension disk infiltrometry, with supply pressure heads (h) from −15 to −120 mm, the steady‐state infiltration rate [i(h)] and hydraulic conductivity [K(h)] were highest shortly after tillage in October, followed by a steep decrease to minimum values in winter and a recovery to intermediate values during spring and early summer. The range in the temporal variation in saturated K was about 65 to 5 and 52 to 8 mm h−1 under CT and RT, respectively. Compared with CT, K(h) under RT was slightly lower shortly after tillage, similar during winter, and considerably higher during early summer. Changes in K were accompanied by temporal variations in pore space characteristics, indicating structural collapse during late autumn and early winter followed by structural recovery with aggregation during spring and summer. The air‐entry pressure head was highest under RT. The effective porosities were found to be smaller, by two to three orders of magnitude, than the equivalent fractional pore volumes estimated from the water retention curves determined on soil cores in the laboratory. Wheel traffic was found to obliterate any differences in hydraulic properties between the tillage treatments. Therefore, compared with CT, RT is likely to improve water availability and soil resilience but offers no comparative advantage for controlling wheel‐traffic‐induced topsoil compaction.

Soil structure and structural stability are key parameters in sustainable soil management and optimum cropping practices. This study aimed to improve the knowledge of potential precision tillage practices by characterizing the effect of varied tillage intensities on structural properties of a clay loam soil. An experiment with seedbed preparation was conducted using a power take-off-driven rotovator equipped to measure torque and angular velocity and with operational speed (OS) and rotational speed (RS) as main factors. Effects of soil coverage prior to tillage and wheeling directly after tillage were measured at one combination of OS and RS. The soil was sampled at 0-80 mm depth. Under slow OS (2.9 km hr −1 ) compared with fast OS (6.3 km hr −1 ), specific energy input was greater (116 and 52 J kg −1 on average, respectively), and it increased with RS. Wheeling resulted in larger aggregate diameter right after tillage (at T1; 56 mm as geometric mean compared with 9 mm), with 42 times smaller geometric mean of air permeability 45 days after tillage (at T2) and with greater soil dispersibility at T2. Highly significant correlations were observed between soil dispersibility and energy input, specific surface area of aggregates, fractions of small (<4 mm) and medium (8-16 mm) aggregates, and geometric mean diameter. Slow OS combined with fast RS showed significantly greater air permeability than all other treatments. The results suggest that there is a potential for controlling soil structure in seedbed preparation by minimizing compaction from traffic and adapting site-specific control of rotovation intensity. K E Y W O R D Sair permeability, specific energy input, structural stability, tillage intensity control

Compaction of agricultural topsoil in wheel tracks has negative impacts on structure, structural stability and permeability of the uppermost soil layers (Daraghmeh et al., 2019). Soil compaction decreases total pore space and hence the total water capacity of soil. For a wide range of tensions, unsaturated water content at hydraulic equilibrium is typically larger in compacted soil than in non-compacted soil (Reicosky, Voorhees, & Radke, 1981). This further reduces air capacity and hence the space remaining to absorb rainwater and retain it under tension. Increased pore tortuosity and decreased volume of large and air-filled pores in compacted soil may also severely reduce the soil's infiltrability (Ankeny, Kaspar, & Horton, 1990). The effect is reported to be most pronounced on tilled and structurally unstable soil, which may partly be

Medical image segmentation and classification algorithms are commonly used in clinical applications. Several automatic and semiautomatic segmentation methods were used for extracting veins and arteries on transverse and longitudinal medical images. Recently, the use of medical image processing and analysis tools improved giant cell arteries (GCA) detection and diagnosis using patient specific medical imaging. In this chapter, we proposed several image processing and analysis algorithms for detecting and quantifying the GCA from patient medical images. The chapter introduced the connected threshold and region growing segmentation approaches on two case studies with temporal arteritis using ultrasound (US) and magnetic resonance imaging (MRI) imaging modalities extracted from the Radiopedia Dataset. The GCA detection procedure was developed using the 3D Slicer Medical Imaging Interaction software as a fast prototyping open-source framework. GCA detection passes through two main procedures: The pre-processing phase, in which we improve and enhances the quality of an image after removing the noise, irrelevant and unwanted parts of the scanned image by the use of filtering techniques, and contrast enhancement methods; and the processing phase which includes all the steps of processing, which are used for identification, segmentation, measurement, and quantification of GCA. The semi-automatic interaction is involved in the entire segmentation process for finding the segmentation parameters. The results of the two case studies show that the proposed approach managed to detect and quantify the GCA region of interest. Hence, the proposed algorithm is efficient to perform complete, and accurate extraction of temporal arteries. The proposed semi-automatic segmentation method can be used for studies focusing on three-dimensional visualization and volumetric quantification of Giant Cell Arteritis.