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Wind erosion refers to the detachment, transport, and deposition of sediment by wind. It is a dynamic, physical process where loose, dry, bare soils are transported by strong winds. Geomorphologists and other earth scientists usually consider wind erosion as a specific subdiscipline of a more broad study of aeolian (also spelled eolian) processes. The term aeolian is derived from the Greek god Aeolus, the keeper of the winds, so aeolian processes refer to effects produced by the force of the wind interacting with surface features. Although aeolian research spans a wide range of topics, which may even include research on other planets, in this chapter we will limit our focus to erosion of soils by the wind on the Earth’s surface, and more specifically on crop land and range land. The movement of sediment by wind has been occurring for many eons, as demonstrated by aeolian cross-bedding seen in wind-blown sands of ancient sandstone bedrock. Loess deposits are ubiquitous accumulations of aeolian sediments of silt, and smaller amounts of clay and sand, derived from wind-blown glacial outwash deposits or from deserts or playa lakes. Large dune fields and sand seas around the world provide further evidence of current and past aeolian environments (Fig. 14|1). Fixed or stable dunes are no longer active in the current climate but were active sand seas or dune fields in the past. Scientists have long been interested in the direct and indirect effects of wind erosion. The earliest publication relating to aeolian processes was written by a Flemish astronomer, Godefroy Wendelin, in 1646 (Stout et al., 2009). Wendelin’s paper (Wendelin, 1646) described the purple rain of Brussels that we now recognize as wet deposition of African windblown dust. Charles Darwin collected dust over the Atlantic Ocean that had fallen during his voyages on the HMS Beagle (Darwin, 1845). Recent analysis of this dust indicated it originated from the Western Sahara and molecular-microbiological methods

A number of scientists have named our age the Anthropocene because humanity is globally affecting Earth systems, including the soil. Global soil change raises important questions about the future of soil, the environment, and human society. Although many soil scientists strive to understand human forcings as integral to soil genesis, there remains an explicit need for a science of anthropedology to detail how humanity is a fully fledged soil-forming factor and to understand how soil change affects human well being. The development and maturation of anthropedology is critical to achieving land-use sustainability and needs to be nurtured by all soil disciplines, with inputs from allied sciences and the humanities,. The Soil Science Society of America (SSSA) has recently approved a cross-divisional Working Group on Soil Change, which aims to advance the basic and applied science of anthropedology, to facilitate networks of scientists, long-term soil field studies, and regional databases and modeling, and to engage in new modes of communications about human–soil relations. We challenge all interested parties, especially young scientists and students, to contribute to these activities and help grow soil science in the Anthropocene.

Global efforts to identify and develop soil quality indices that can accurately and efficiently quantify effects of soil and crop management began to emerge around the world during the latter portion of the 20th century. This occurred as people became more aware that soil is a unique, nonrenewable resource that nurtures and sustains human civilizations (McNeill and Winiwater, 2004). These efforts have been further encouraged by a growing awareness of the multiple ecosystem services that soil resources provide to sustain food security, environmental quality, ecological functions, and most recently feedstock production for biofuels (Doran et al., 1996; Bouma, 2005; Lal, 2007). In addition to serving as assessment tools, soil quality indices also provide land managers with a better understanding of how their short-term, economically driven management decisions are affecting soil properties and processes over time.

Soil quality assessment may be one of the most contentious topics ever debated by the soil science community. Our objective is to examine the history, present status, and potential for using soil quality assessment as a tool to monitor soil physical, chemical, and biological effects of management decisions that may affect soil and water resources. Differences between inherent and dynamic soil quality and various approaches for assessment are identified and discussed. Four assessment indices, the Agroecosystem Performance Assessment Tool (AEPAT), Soil Conditioning Index (SCI), Cornell Soil Health Test, and Soil Management Assessment Framework (SMAF) are examined. The SCI predicts changes in soil organic matter (SOM) and is a good first step toward more comprehensive assessment, but it focuses only on a single indicator. The AEPAT, Cornell Soil Health Assessment, and SMAF offer a more comprehensive soil quality assessment by including biological, chemical, and physical indicators. One SMAF study showed that including at least three years of forage resulted in higher index values than growing continuous corn (Zea mays L.) because the latter had lower soil pH, decreased macro-aggregate stability, and lower microbial biomass carbon. Another study within the Iowa River South Fork watershed showed that overall, soils were functioning at 87% of their full potential. The lowest indicator score was associated with SOM (0.60) because the average value was only 28.4 g kg-1. A third study showed that the SMAF could separate cropping groups not recognized by the SCI. Opportunities for collaboration to further improve the SMAF are discussed with the long-term goal being to provide tools to help guide soil management and use decisions and thus ensure longterm sustainability of our soil, air and water resources.