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The NRI is important in the development of conservation policy and programs and is a nationally consistent source of data for the public and researchers in many fields. In 1995, [...]

Land managers and policymakers need information about soil change caused by anthropogenic and non-anthropogenic factors to predict the effects of management on soil function, compare alternatives, and make decisions. Current knowledge of how soils change is not well synthesized and existing soil surveys include only limited information on the dynamic nature of soils. Providing information about causes and attributes of soil change and the effects of soil change on soil function over the human time scale (centuries, decades, or less) should be a primary objective of 21st century soil survey. Soil change is temporal variation in soil across various time scales at a specific location. Attributes of change include state variables (dynamic soil properties), reversibility, drivers, trends, rates, and pathways and functional interpretations include resistance, resilience, and early warning indicators. Iterative elements of the blueprint for action described in this article are: (i) identify user needs; (it) conduct interdisciplinary research and long-term studies; (iii) develop an organizing framework that relates data, processes, and soil function; (iv) select and prioritize soil change data and information requirements; (v) develop procedures for data collection and interpretation; and (vi) design an integrated soil-ecosystem-management information system. Selection of dynamic soil properties, soil change attributes, and functional interpretations to be included in future soil surveys should be based on analyses comparing the benefits of meeting user needs to the costs of data acquisition and delivery. Implementation of the blueprint requires increased collaboration among National Cooperative Soil Survey partners and other research disciplines.

Shrub-dominated communities have replaced native grasslands throughout much of the arid Southwest during the past 120 years. Most currently available remediation technologies are uneconomical due to large inputs of energy, [...]

ABSTRACT: The estimated properties for soil survey map units typically are only for major soil use. Users are provided only one set of soil properties. We consider the combination of [...]

Abstract: We compared short-term effects of lug-soled boot trampling disturbance on water infiltration and soil erodibility on coarse-textured soils covered by a mixture of fine gravel and coarse sand over weak cyanobacterially-dominated biological soil crusts. Trampling significantly reduced final infiltration rate and total infiltration and increased sediment generation from small (0.5m2) rainfall simulation plots (p <0.01). Trampling had no effect on time to runoff or time to peak runoff. Trampling had similar effects at sites with both low and very low levels of cyanobacterial biomass, as indicated by chlorophyll a concentrations. We concluded that trampling effects are relatively independent of differences in the relatively low levels of cyanobacterial biomass in this environment. Instead, trampling appears to reduce infiltration by significantly reducing the cover of gravel and coarse sand on the soil surface, facilitating the development of a physical crust during rainfall events. The results of this study underscore the importance of carefully characterizing both soil physical and biological properties to understand how disturbance affects ecosystem processes. [Copyright &y& Elsevier]

Ultra-high-resolution digital aerial imagery has great potential to complement or replace ground measurements of vegetation cover for rangeland monitoring and assessment. This research investigated object-based image analysis (OBIA) techniques for classifying vegetation in southwestern USA arid rangelands with 4 cm resolution digital aerial imagery. We obtained high r-square values for the regressions relating ground- to image-based measures of percent cover (r-square values: 0.82-0.92). OBIA enabled us to automate the classification process and demonstrated potential for quantifying fine-scale land cover attributes with ultra-high-resolution imagery. This approach exhibits promise for nationwide application for monitoring grazing lands. [ABSTRACT FROM AUTHOR]

Traditional methods of reseeding degraded arid and semi-arid rangeland are expensive and frequently unsuccessful due to high rates of seed predation and seedling mortality. A runoff-based method is described that protects seeds from predation and degradation until soil moisture is available, then deposits them in favorable microsites for germination and establishment. Seeds are placed in three, 2 cm-diameter x 8 cm PVC tubes. The small tubes are capped with crepe paper and glued inside of a 7.5 cm-diameter × 15 cm-long tube which is capped with hardware cloth. The tubes are placed in small rills, gullies, arroyos or riparian areas and the seeds are released sequentially from the 3 tubes as flow depth increases. Seeds are deposited beneath piles of litter where soil moisture and temperature are more favorable for seedling establishment. [ABSTRACT FROM AUTHOR]