Abstract Knowledge of plant root responses to both favorable and unfavorable soil conditions is fundamental our understanding the complex interface. One greatest hindrances frequent measurements morphological physiological roots environmental has been absence an inexpensive method for quantitatively separating from other biological materials. The objectives this study were develop quantitative soils field greenhouse experiments determine influence type, pretreatment type on efficiency...

Pore network geometries of intra‐aggregate pore spaces are great importance for water and ion flux rates controlling C sequestration bioremediation. Advances in non‐invasive three‐dimensional imaging techniques such as synchrotron‐radiation‐based x‐ray microtomography (SR‐μCT), offer excellent opportunities to study the interrelationships between geometry physical processes at spatial resolutions a few micrometers. In this paper we present quantitative pore‐space analyses small scale (∼5 mm...

Cycles of wetting and drying (WD) occur naturally in soils affect the pore structure through altered hydraulic stresses. Two organic‐rich soils, a Eutric Histosol Histic Gleysol, two inorganic Calcic Gleysol Dystric ranging texture microstructure, were investigated. Undisturbed soil samples predried to either −100 kPa water potential by using ceramic plate or 30°C an oven then resaturated for one three WD cycles. In addition, different combinations defined intensity, frequency, sequence...

Recent advances in computed tomography provide measurement tools to study internal structures of soil aggregates at micrometer resolutions and improve our understanding specific mechanisms various processes. Fractal analysis is one the data that can be helpful evaluating heterogeneity intra-aggregate structures. The goal this was examine how long-term tillage land use differences affect pore heterogeneity. objectives were: (i) develop an approach enhance utility box-counting fractal...

New evidence confirms earlier postulates that root signals to shoots, including abscisic acid, nitrate flux, and cytokinins, modify whole plant growth processes leaf expansion, stomatal behavior, biosynthesis of photosynthetic enzymes. Root are thought reflect soil water, nutrient, mechanical attributes, as sensed by roots. Meristematic activities in tips initiate changes architecture, modifying the volume subject uptake, may provide multiple sensory signaling capabilities. Knowledge...

Although alfalfa ( Medicago sativa L.) stands have been reported to improve soil physical properties, little is known about the specific influences of above‐ and belowground components on properties. A 2‐yr study was conducted investigate root shoot mulch modifications properties water movement in zone a Kalamazoo loam (fine‐loamy, mixed, mesic Typic Hapludalf) southwest Michigan. Four treatments were considered: bare fallow (BF), with (BFSM), shoots removed roots remaining (AR), (ASM)....

Soil biophysical transport mechanisms promoting biogeochemical sorption of soluble organic carbon (SOC) compounds within macroaggregates control the retention and release most soil nutrients, C‐ N‐based polysaccharides, contaminants. Ecosystems containing continuous supplies root exudates particulate matter (POM) provide a constant supply mobile SOC to surfaces internal pore networks aggregates. Intra‐aggregate pores, especially ultrafine appear be developed, interconnected, blocked or...

Intra-aggregate pores play an important role in controlling soil processes on a micro-scale. Differences parent materials, pedogenic processes, land use, and management practices can have substantial effect their characteristics. The goal of this study is to examine intra-aggregate pore characteristics using X-ray computed microtomography (μCT) images soils two contrasting materials use management. In addition, quantify aggregate exterior interior layers we developed approach for boundary...

Beneficial microbes in the microbiome of plant roots improve health. Induced systemic resistance (ISR) emerged as an important mechanism by which selected growth–promoting bacteria and fungi rhizosphere prime whole body for ...Read More

Abstract Soil compaction and the incipient aeration mechanical impedance stresses are known to reduce root growth function. Little is known, however, regarding influence of accumulations adjacent a compacted area upon status soil profile below mass. This study was designed measure plant interactions with compaction. A clay bulk densities in 1.1, 1.4 1.7 Mg m −3 columns planted dry edible bean ( Phaseolus vulgaris L.). Mechanical resistances these treatments were 0.43, 2.14, 5.50 MPa,...

Greater knowledge of intraaggregate porosity modifications by tillage conveys new information for identifying additional hydrologic, ion retention, and aggregate stability responses to specific management practices. Macroaggregates, 2 4, 4 6.3, 6.3 9.5 mm across, were separated into multiple concentric layers their porosities determined. Saturated hydraulic conductivity (Ks) fractions from two soil types subjected conventional (CT), no (NT), native forest (NF) soils measured individually...

The concentration and δ15N of NO3− in leachate from two undisturbed unfertilized soil lysimeters, one conventionally tilled with no tillage, was determined on a bi-weekly basis March through November, 1993 to assess the origins transformations leaching an agricultural soil. Concentrations lysimeter were approximately twice those non-tilled throughout year are consistent observations that tilling favors mineralization process soils. Although difference between lysimeters evident, both...

Water absorption is influenced by the geometric distribution of viable roots and availability water at root surfaces. Utilization additional plant energy for extensive localized development systems a high risk investment carbon plant, especially during short-term deficits. Nonuniform distribution, resulting from growth within networks continuous soil macropores, reduces efficiency minimizing contact between increasing mean pathway bulk to root. Root clustering in these niches causes greater...