SSSAJ: Volume 75: Number 6 ? November?December 2011 2079 Soil Sci. Soc. Am. J. 75:2079?2084 Posted online 27 Sept. 2011 doi:10.2136/sssaj2011.0124 Received 4 April 2011. *Corresponding author (drichter@duke.edu). ? Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher. Human?Soil Relations are Changing Rapidly: Proposals from SSSA?s Cross-Divisional Soil Change Working Group Soil Science Issues Daniel deB. Richter* Allan R. Bacon Megan L. Mobley Curtis J. Richardson Nicholas School of the Environment Duke Univ. Durham, NC 27708 Susan S. Andrews Larry West Skye Wills USDA-NRCS National Soil Survey Center Lincoln, NE 68508 Sharon Billings Dep. of Ecology and Evolutionary Biology Kansas Biological Survey Univ. of Kansas Lawrence, KS 66047 Cynthia A. Cambardella USDA-ARS National Lab. for Agriculture and Environment Ames, IA 50011 Nancy Cavallaro USDA National Institute of Food and Agriculture Washington, DC 20024 Julie E. DeMeester Arlington, VA 22209 Alan J. Franzluebbers USDA-ARS J. Phil Campbell Sr. Natural Resource Conservation Center Watkinsville, GA 30677 A. Stuart Grandy Dep. of Natural Resources and Environment Univ. of New Hampshire Durham, NH 03824 Sabine Grunwald Soil and Water Science Dep. Univ. of Florida Gainesville, FL 32611 Joel Gruver School of Agriculture Western Illinois Univ. Macomb, IL 61455 Anthony S. Hartshorn Dep. of Geology and Environmental Science James Madison Univ. Harrisonburg, VA 22807 Henry Janzen Agriculture and Agri-Food Canada Lethbridge Research Centre Lethbridge, AB, T1J 4B1 Canada Marc G. Kramer USDA Forest Service Portland, OR 97204 Jagdish K. Ladha IRRI New Delhi 110012, India Kate Lajtha Dep. of Crop and Soil Science Oregon State Univ. Corvallis, OR 97331 Garrett C. Liles Dep. of Land, Air, and Water Resources Univ. of California Davis, CA 95616 Daniel Markewitz Warnell School of Forestry and Natural Resources Univ. of Georgia Athens, GA 30602 Patrick J. Megonigal Smithsonian Environmental Research Center Smithsonian Institution Washington, DC 20013 Ahmet R. Mermut Dep. of Soil Science Univ. of Saskatchewan Saskatoon, SK, S7N 5A2 Canada Craig Rasmussen Dep. of Soil, Water, and Environmental Science Univ. of Arizona Tucson, AZ 85721 David A. Robinson Centre for Ecology and Hydrology Environmental Centre Wales Bangor, Gwynedd, LL57 2UW UK Pete Smith School of Biological Sciences Univ. of Aberdeen Aberdeen AB24 3UU UK Cynthia A. Stiles USDA-NRCS Pacifi c Islands Area State Offi ce Honolulu, HI 96850 Robert L. Tate III Dep. of Environmental Sciences Rutgers Univ. New Brunswick, NJ 08901 Aaron Thompson Dep. of Crop and Soil Sciences Univ. of Georgia Athens, GA 30602 Arlene J. Tugel USDA-NRCS Las Cruces, NM 88003 Harold van Es Dep. of Crop and Soil Sciences Cornell Univ. Ithaca, NY 14853 Dan Yaalon Inst. of Earth Sciences Hebrew Univ. Jerusalem, Israel 91904 Ted M. Zobeck USDA-ARS Cropping Systems Research Lab. Lubbock, TX 79415 A number of scientists have named our age the Anthropocene because humanity is globally aff ecting 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 fl edged soil-forming factor and to understand how soil change aff ects human well being. Th e development and maturation of anthropedol- ogy is critical to achieving land-use sustainability and needs to be nurtured by all soil disciplines, with inputs from allied sciences and the humanities,. Th e 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 fi eld 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. 2080 SSSAJ: Volume 75: Number 6 ? November?December 2011 Soil science and pedology are sciences of change. In the past, pe-dologists focused mainly on natural soil-forming factors and pro- cesses, i.e., on soil changes that take place on the natural pedogenic clock, spanning centuries to thousands and millions of years (Jenny, 1941; Simonson, 1959; Cline, 1961; Buol et al., 2003; Schaetzl and Anderson, 2005). Th e venerable soil scientist E.W. Hilgard (1860), when asked the question ?What is soil??, stated clearly his abiding interest in ?the virgin soil?, soil not infl uenced by humanity. Th e natural-body orientation of soil science and pedology has recently motivated Dudal et al. (2002) to critique our science by asking simply, ?Are we a soil-forming factor short?? Indeed, many soil and environmental scientists now recognize the extent, complexity, and intensity of human infl uences on soil (Richter and Markewitz, 2001; Galbraith, 2006; Dazzi et al., 2009). Some strive to understand human alterations of soil not only as a soil disturbance but as an integral part of soil genesis. Human forc- ings, both planned and capricious, are redirecting the course of the natural forces that have long driven natural soil genesis. Th ere is great need for a science of anthropedology to more fully un- derstand humanity as a soil-forming factor. Here we use broad defi nitions of soil, ecosystems, pedology, and soil science to consider how humanity is changing the soil and soil?environment interactions and how soil change is impact- ing humanity. For good reason, some geologists have suggested naming our epoch the Anthropocene (Crutzen, 2002; Zalasiewicz et al., 2011, Anonymous, 2011), an idea whose roots originated in the 19th and 20th centuries (Marsh, 1874; Vernadsky, 1945; Osborn, 1948). Humanity has rapidly become Earth?s chief agent of soil change and we are substantially altering the soil with well- documented eff ects on erosion and sedimentation (Hooke, 2000; Wilkinson, 2005), the C cycle (Houghton, 2007), the N cycle ( Johnson and Lindberg, 1992; Vitousek et al., 1997), the P cycle (Filippelli, 2008; Richardson, 2008), climate systems (Robertson et al., 2000), and hydrology, salinity, and water quality (Postel et al., 1996; Pitman and L?uchli, 2002). Although we are greatly con- cerned about human-forced soil change as a degradation of natural capital (Palm et al., 2007; Robinson et al., 2009), humans also alter soils in ways that are benefi cial to humanity and the environment. Excellent examples include ecosystem restoration (Craft et al., 2003) and soil amendments such as liming (Farina et al., 2000). In fact, if humanity is to improve environmental management in the coming few decades, we must manage a great diversity of soils much more positively (Buol et al., 2003; Schaetzl and Anderson, 2005; Johnson, 2005; Palm et al., 2007; Dominati et al., 2010). Soils have long memories; they quietly record the history of natural and human impacts, with new changes laid down on those from the past (Targulian and Goryachkin, 2004). To predict how human forcings infl uence soils locally or globally, we need a much better understanding of the legacies of human impacts on soils and of soil infl uences on humanity (Showers, 2006; Ramankutty et al., 2008). In particular, we know far too little about the rates of soil change in response to land management, about soil resilience to historic and contemporary management, and about soil response rates to improved land management and changes in climates. Today, more than half of the Earth?s soils are cultivated for food crops, grazed or managed for domesticated animals, or pe- riodically logged for wood (Ellis, 2011). In addition, soils are manipulated for residential, industrial, transportation, and recre- ational development; exposed to many and various disturbances that alter their hydrology, plant community composition, and nu- trient cycling; chemically contaminated; used for waste disposal; and subject to climate change. Each of these alterations of soils has reciprocal infl uences on humanity that are too rarely explored. Two dramatic examples in the United States of recipro- cal impacts of large-scale anthropogenic soil transformations and human well-being are the Dust Bowl of the 1930s and wetland drainage. Th e Dust Bowl resulted from a combination of problems including large-scale misuse of land and decadal climate shift s. It displaced more than 2.5 million people from their homes and farms. A full understanding of this land and soil crisis includes not only scientifi c investigations such as the new geospatial historical assessment ?Scaling the Dust Bowl? by Geoff Cunfer (2008), but also the novel Grapes of Wrath by John Steinbeck (1940), and even the controversial environmental history Dust Bowl by Donald Worster (2004; see also Trimble, 2010). Th e reciprocal eff ects of large-scale land transformations and humanity are also seen in our second example of wetland drainage. In the United States, about 45 million ha of hydric wetland soils have been drained and converted to agricultural and residential uses (Dahl, 2006). Like nearly everywhere land is drained, agricultural and forestry productivity have been im- pressive, and the historian Fernand Braudel (1974) has described well the far-reaching eff ects of drainage on landscapes, econom- ics, and culture. But as demonstrated by the recent Mississippi River fl oods of 2011, drainage alters the hydrology at a range of spatial and temporal scales, and even drained land is periodically at odds with larger scale Earth processes such as fl ooding. Such interactions of humanity and soil change are part of the process of soil and landscape domestication (Hole, 1974) and the creation of anthropogenic biomes (Ellis and Ramankutty, 2008). To better understand this process of global soil change (Arnold et al., 1990), soil scientists need broad ties across the sciences and the humanities. Specifi cally, soil scientists need new alliances with anthropologists, historians, philosophers, economists, engineers, archaeologists, social scientists, geographers, and psychologists to more fully understand human?soil interactions. WHY IS SOIL CHANGE IMPORTANT TO SSSA AND TO SOCIETY AT LARGE? Th e history of agricultural management during the past 50 yr illustrates well the vast productivity of soils worldwide, as ag- ricultural outputs grew to feed a doubling of the human popula- tion. Th is period of the Green Revolution witnessed a tripling in global crop production and the most rapid improvement in the average human diet in history (Richter et al., 2007). Even still, many of society?s most important scientifi c ques- tions concern the immediate future of Earth?s changing soils, and these questions need to be articulated clearly and forcefully by soil SSSAJ: Volume 75: Number 6 ? November?December 2011 2081 scientists. For example, how can we further expand crop produc- tion in the coming decades, keeping pace with human needs and demands for food and other products while improving environ- mental quality? Land management is already pressing hard on soils, freshwater and marine resources, the atmosphere, and ecosys- tem services. Many scientists and managers are deeply concerned about the future functioning and health of soils and ecosystems, including in the context of climate change (National Research Council, 2010). Today we face larger challenges than those faced by the Green Revolutionaries of the mid-20th century, for our chal- lenges are both quantitative and qualitative. Th e question of how we can manage more production from soils and ecosystems but at the same time improve soil and ecosystem services can hardly be answered by soil science alone (Daily, 1997). Th is question demonstrates why contemporary soil science needs to work closely with allied sciences and the humanities. Th ere are many important soil frontiers for young scientists to explore and a most important measure of SSSA?s success must be based on its attraction of the best scientists to quantify how and why soils are changing in local and global systems and in re- lation to the wider environment. Understanding soil?s resistance and resilience (Greenland and Szablocs, 1994; Holling, 1996; Seybold et al., 1999), thresholds (Chadwick and Chorover, 2001; Bestelmeyer, 2006), early warning indicators, and hystereses are all critical to predicting soil change. Soil?s vulnerability (and resis- tance) to change forced by land use, pollution, climate, or natural vegetation succession must be quantifi ed and predictable. Th e SSSA has a special responsibility not only to attract high quality students, but to promote high-quality research opportuni- ties and help integrate scientifi c results in policy analysis and deci- sion making. Specifi c issues that require soil expertise can hardly be more compelling. Included are questions about: sustaining and improving food, fi ber, and bioenergy production systems; mini- mizing greenhouse gas emissions; maintaining more balanced soil C cycles, diminishing wind and water erosion and sedimentation, cycling nutrients and water more effi ciently, improving water qual- ity, preserving biodiversity and soil organic matter, and preventing or mitigating natural catastrophes such as fl ooding and landslides ( Janzen et al., 2011). Given the acceleration of global soil change, the SSSA must continually address these soil issues with vigor and persuasive communication with scientists and non-scientists alike, describing the inseparable coupling of soil with water, air, climate, and the fate of civilization itself. PROPOSALS FOR A CROSS-DIVISIONAL SSSA AGENDA Although soil science is interdisciplinary (Cline, 1961), an- thropedology must cast an especially wide net to address basic and applied objectives and interact extensively with the environ- mental, ecological, and earth sciences, social sciences (Tugel et al., 2005; Wilding and Lin, 2006), and the humanities (Showers, 2006; McNeill and Winiwarter, 2006). New synergies can derive from projects that span the disciplines and divisions of SSSA and that involve members of other professional societies (Wilding and Lin, 2006). Contemporary soil science must embrace all human relations with soils, a breadth that can help us articulate more fully how soils are the basis for sustaining civilization. To stimulate greater SSSA discussion across divisions about the challenges faced by contemporary soil science, a cross-divi- sional Soil Change Working Group was formally launched within SSSA in 2009. Th is working group fosters interdisciplinary col- laboration on soil issues aff ected by human forcings. Documents describing the mission, suggested activities, functions, and work- ing group by-laws were prepared for the group?s fi rst meeting in Pittsburgh, PA, led by Arlene Tugel and Susan Andrews. In 2010, at SSSA?s Long Beach meetings, the working group sponsored a symposium entitled ?Soil Change: Management Practices and Policy,? featuring invited presentations by Henry Janzen and Karl Glasener on the science and policy of soil change, followed by a panel discussion with Julie DeMeester, Daniel Richter, Robert L. Tate III, and Harold van Es. Th e S1 Soil Physics and S5 Pedology divisions organized symposia entitled, ?Soil Change: Characterization and Modeling Across Scales? and ?Anthropogenic Soil Change: A New Frontier for Pedologists.? Since the meetings, the Soil Change Working Group has created a web site (www.soils.org/about-society/soil-change; verifi ed 22 Aug. 2011) and draft ed this narrative to help advance their agenda. Th e Soil Change Working Group challenges all interested parties to participate as it initiates three activities to advance: (i) a more explicit science of human?soil relations, i.e., anthrope- dology; (ii) greater networking of researchers, research sites, landscape-scale data sets, and models to quantify global soil change; and (iii) new forms of communication that articulate the importance of soil, soils research, and human?soil relations. To accomplish these tasks, the SSSA Soil Change Working Group will work jointly with the International Union of Soil Sciences (IUSS) Working Group on Global Soil Change and with individuals and groups from other professional societies, e.g., the American Association for the Advancement of Science, the American Geophysical Union, the National Cooperative Soil Survey, and the Ecological Society of America. Th e joint SSSA?IUSS activities in the history, philosophy, and sociology of soil science serve as a model for cooperation (www.iuss.org/ Newsletter_%20Number%2018.pdf; verifi ed 22 Aug. 2011). Some detail describing these three agenda activities follow: Anthropedology Th e SSSA working group will draw on expertise from across SSSA divisions to help advance the science of anthropedology, the basic and applied science of how humans change soils and soil interactions with the wider environment and how soil changes impact humanity. With natural soil bodies becoming the parent material for human-altered soil systems (Yaalon and Yaron, 1966), all soil disciplines need to more fully integrate humanity within the concept of soil and soil change (Bidwell and Hole, 1965; Amundson and Jenny, 1991; Dudal et al., 2002; Richter, 2007). 2082 SSSAJ: Volume 75: Number 6 ? November?December 2011 A more explicit understanding of anthropedology serves sev- eral aims: (i) ensuring the sustainability of soil outputs of food, fi ber, bioenergy, and all vital ecosystem services that support the well-being of humanity; (ii) minimizing adverse impacts of soil management on the environment, especially its biodiversity and the functioning of the atmosphere, hydrosphere, and biosphere; (iii) conserving and restoring high-quality examples of natural soil bodies that are other- wise at risk of extinction (Amundson et al., 2003); and (iv) fostering new unifying theories and understanding of anthropedology and human?soil relations. All divisions of SSSA can contribute to and gain from anthropedology because humanity signifi cantly infl uenc- es soil physical, chemical, and biological features and functions; soil fertility and plant nutrition; pedogenesis; soil-water management and conservation; forest, range, and wildland soils; nutrient man- agement and cycles; soil mineralogy; wetland soils; and interactions between soils and environmental quality. Networking Th e new science of anthropedology requires the networking of researchers with varied expertise and a networking of long- term, local fi eld research sites, extensive databases, and modeling. At the local scale of individual management units, i.e., farm- ers? fi elds and foresters? stands, hundreds of fi eld experiments, known as long-term soil experiments (LTSEs), attempt to dem- onstrate directly and precisely how soil properties and functions respond to management regimes across annual to decadal time scales (Debreczeni and K?rschens, 2003; Richter et al., 2007; Janzen, 2009; Schillinger, 2011). Th e Soil Change Working Group will promote the research of these long-running fi eld studies by encouraging and coordinating: (i) meta-analyses of soil-change data from across LTSEs to address critical manage- ment and scientifi c questions about sustainable soil management (e.g., about production trends, C and nutrient cycling, and phys- ical, chemical, and biological processes contributing to on- and off -site eff ects of management); (ii) new hypothesis-driven re- search about soil sustainability, including new sampling, analyses of soil archives, and modeling and decision-tool development for explanatory and predictive purposes (Smith et al., 1997, 2000); and (iii) establishment of new LTSEs to respond to emerging is- sues in land management and soil and environmental science. At larger spatial scales of landscapes, regions, and the globe, opportunities for estimating and predicting soil change are many and diverse. Assessments of landscape-scale soil change include data set assembly, meta-analyses, and large-scale soil-change mod- eling. A number of eff orts to harmonize and assess soil proper- ties using digital soil mapping techniques are well underway. Th e NRCS is using new geospatial methods to better analyze its ex- tensive soil survey data, including historic soil data (the National Cooperative Soil Characterization Database). Th e NRCS has also launched the ?Rapid Assessment of U.S. Soil Carbon for Climate Change and Conservation Planning? to be based on 35,000 new sampling sites and has created a new Soil Ecology Branch at the National Soil Survey Center focused on soil-change issues. Th e National Ecological Observatory Network, Critical Zone Exploratory Network and Critical Zone Observatories (CZEN and CZO), and SoilTrec programs each represent ambitious new eff orts to research and reconceptualize the Earth?s surfi cial systems, eff orts supported both in the United States and abroad (Wilding and Lin, 2006). Th e NRCS, National Park Service, ARS, and other federal agencies are documenting land management eff ects on dynamic soil properties (Tugel et al., 2008), and the USGS continues to build its large, geographically explicit geochemistry databases (minerals.cr.usgs.gov/projects/geochem_database/; ver- ifi ed 22 Aug. 2011). In the United Kingdom and Belgium, large- scale and policy-relevant soil sampling has been conducted for several decades (Emmett et al., 2010; Goidts and van Wesemael, 2007); these approaches aim to detect regional changes in acid- ity, C content, heavy metals, and metal chemistry. In the United States, research-driven projects are assessing soil C changes across large landscapes (Sabine Grunwald, personal communication, 2010) and across research sites (National Soil Carbon Network). Th e Soil Change Working Group can serve as a forum for how to better combine disparate data sets in meta-analyses and re- gional assessments of changes in soil properties and processes (e.g., Franzluebbers and Follett, 2005). Integration of large-scale data sets and modeling (e.g., using spatiotemporal soil data, remote- sensing-derived environmental data, digital soil mapping, soil sen- sor data, and environmental geographic information system data) can benefi t both soil science and land management decision mak- ing (Grunwald, 2006, 2009). Such data-rich projects are develop- ing quickly, driven in part by technological advances. Technological advances also impact operational applica- tions of soil management. Various tools have been developed to assess changes in soil quality and function, for example, the Soil Management Assessment Framework (Andrews et al., 2004) and the Cornell Soil Health Test program (Idowu et al., 2009); many more are being developed. Regional data and information can now be effi ciently delivered by iPhone and other mobile devices that can circulate large and complex geospatial data to land man- agers, scientists, and the public (Beaudette and O?Geen, 2010). Increasingly sophisticated tools that are useable on all continents may greatly improve soil?s ability to produce recurring streams of food, fi ber, bioenergy, and ecosystem services. Communication Th e cross-divisional working group will use a variety of communication and education tools to articulate how soils are central to human well-being and the environment. Th e working group can be a test bed for exploring new ways of communicating this urgent message, e.g., by promoting campaigns to write opin- ion?editorials, commentaries, and blogs (Yaalon, 2000, 2007; Robertson, 2008; Richter et al., 2009; Richter and Mobley, 2009; Grandy et al., 2010; Billings et al., 2010; Robinson and Lebron, 2010). Th ese eff orts can draw from the breadth of SSSA membership, articulating clear text, stories, and visual images for the public and for society?s leaders, policymakers and analysts. Increasing the infl uence of soil scientists will happen only if more of us take defi nitive steps to eff ectively communicate the impor- SSSAJ: Volume 75: Number 6 ? November?December 2011 2083 tance of soils and soils research, the many important opportu- nities available for students and young scientists, and the need for policy-instructive recommendations on issues related to soil resources. Th is means motivating greater communication from more individuals across the SSSA and requires more coordina- tion among the divisions of SSSA and between SSSA and other major organizations in environmental science and policy. IMPORTANT CHALLENGES AHEAD In 1937, the geographer Carl Sauer sharply questioned hu- manity?s future and observed that humanity had ?not yet learned the diff erence between yield and loot? (Sauer, 1937). Whether we can signifi cantly move human?soil relations from exploita- tion and loot toward sustainability is a more urgent question now than ever before and can resonate widely with soil scientists, land managers, and the general public. Given the rushing pace of soil change in the Anthropocene, we must learn the diff er- ence between yield and loot in the coming decades and adjust our uses of soils accordingly. Th e stakes are high, for soil and the biosphere and for humanity. 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