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8/4/2019 Eight Issues

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Science

Critical

Issuesfacing

humanity and how

Soil Scientistscan address them



April 2011 CSA News 5

Food: How Can We Feed Billions

More without Harming Our Soils or the

Broader Environment?

By 2050, global population may exceed 9 billion, anincrease o more than 2 billion rom today (United Nations,2008). Daily per capita ood consumption, now

∼12 MJ, may

reach ∼13 MJ (∼3,100 kcal) beore leveling o (FAO, 2006).Furthermore, as incomes grow in developing countries, sodo appetites or animal products, increasing the demand oreed. These actors and others have led some to project thatglobal ood requirements may increase by more than 50%

by 2050 (Glenn et al., 2008; Godray et al., 2010).

One undamental question or soil scientists to ask is:Where should we aim to produce more? Where are poten-tial increases the highest—in developing countries whereneeds are greatest? And where will such increases exert theleast pressure on soils and other resources?

Soil scientists will also want to ask: How should we aim

to produce more? Sometimes the best approach might be tointensiy existing arming systems—with better genotypes;more advanced methods o ertilizing, tilling, and planting;and improved control o weeds and other pests. Elsewhere,pushing current systems harder may unduly damage theland, and we may need to explore undamentally re-arranging systems by asking venturesome questions. Whatis the place o “organic” arming systems or o geneticallyrecongured crops? How can we exploit the innate advan-tage o ruminant livestock while reducing the environmen-tal impact o some intensive eeding practices? Should we

Editor’s note: The ollowing article was originally published inthe Soil Science Society of America Journal (75:1–8) and is

reprinted here in a modifed ormat.

The biosphere, our ragile and exquisite home, ischanging abruptly and irrevocably, largely romhuman intererence. Most or all o the coming

stresses have links to the land, so nding hopeul outcomes

depends on a wide and deep understanding o soils. In thisarticle, we pose eight urgent issues conronting humanityin the coming decades: demands or ood, water, nutrients,and energy; and challenges o climate change, biodiversity,“waste” reuse, and global equity. We then suggest somesteps soil scientists might take to address these questions:a reocusing o research, a broadening o vision, a renewedenticement o emerging scientists, and more lucid telling opast successes and uture prospects. The questions posedand responses posited are incomplete and not yet ully re-ned. But the conversations they elicit may help direct soilscience toward greater relevance in preserving our ragilehome on this changing planet.

The terrestrial landscape—our exquisite, ragile home on

this planet—is acing upheavals perhaps as tumultuous asany in human history (Moore, 2002; Millennium EcosystemAssessment, 2005). These rapid changes, discernible evenin our own brie lie spans, are mostly our own doing—theleavings o our burgeoning billions, squeezed ever tighterinto a nite planet with dwindling resources.

Finding pleasant passage through the coming bottleneck(Wilson, 2002) will be a challenge o scale and gravity notseen beore. And the place to start, we propose, is by know-ing the soil. Although new technology may delay somestresses, the enduring answer will come rom more humbleaims: learning to live on the land. It is the land—oundedon soil but interwoven with lie and processes above and

below it—that ultimately sustains us. Peoples in the past,now gone, did not learn that in time (Diamond, 2005). We,no less than they, are nourished in body and spirit by theecosystems in which we are enmeshed, sometimes oblivi-ously.

In this essay, we explore some urgent questions acinghumanity in the coming decades and ponder how we, whostudy the land, might help resolve those challenges. We aimmerely to ask the questions and proer some initial mus-ings in the hope o spurring conversation in soil science andaliated communities.

by H.H. Janzen, P.E. Fixen, A.J. Franzluebbers, J. Hattey, R.C. Izaurralde,

Q.M. Ketterings, D.A. Lobb, and W.H. Schlesinger

P h o t o

b y M a r c o D o r m i n o ( U n i t e d N a t i o n s )

1



Science

6 CSA News April 2011

aim or more intensive production on smaller areas (landsparing) or more environmentally benign production on ex-panded areas (Balmord et al., 2005; Matson and Vitousek,2006)? What are the prospects or urban arms (Drechseland Dongus, 2010)?

It is not just a question o producing more ood, but alsoo ensuring that we do not impinge on the capacity o oth-ers—notably our descendents—to derive rom the soil theirood and other services. The soil scientist, then, may step

beyond merely measuring how current ways o produc-ing ood aect the soil to exploring new approaches thatincrease ood yield and preserve other ecosystem unctions.

Fresh Water: How Can We

Manage Our Soils to UseDwindling Pools More Wisely?

Our planet is bathed in water. But o all water on earth(∼1.4 billion km3), only ∼3% is “resh,” and most o thatis locked up in polar ice caps, glaciers, or undergroundreservoirs, leaving only a raction available or humans andterrestrial ecosystems (Schlesinger, 1997; Oki and Kanae,2006; Jury and Vauz, 2007).

For a long time, resh water was seen as plentiul onearth—and squandered accordingly. But now, in the 21stcentury, resh water is growing scarce as demands expandand the remaining pools are being drained or ouled.Already, some underground reservoirs are being quickly

depleted, oten to irrigate crops, and ew major rivers arelet to dam (Nilsson et al., 2005). With changing climate andcontinued population growth, these water shortages arelikely to urther intensiy (Vörösmarty et al., 2004; Rosegrantet al., 2009).

How, then, do we manage water in the decades ahead tosatisy human and ecosystem needs on a warming planet?One way is to rely more on vertical fuxes o water (“green”water—precipitation and transpiration) and less on lat-eral fuxes (“blue” water—aquiers, lakes, and reservoirs)(Falkenmark and Rockström, 2006). Can we urther improve

water use eciency on arms by managing soil disturbance,plant populations, and nutrient pools (Hateld et al., 2001;Turner, 2004; Passioura and Angus, 2010)? Can improvedunderstanding o the plant–soil system lead to cultivarswith higher water use eciency (Morison et al., 2008)? Andcan we reduce the polluting eects o agriculture, therebykeeping more water resh?

Averting the threats o widespread water shortages isalready an urgent global objective (Anonymous, 2008), andclimate change may urther exacerbate shortages (Chapinet al., 2008; Schimel, 2007). Much o the actively circulat-ing resh water on our planet percolates through the soil,at one point or another, and soil science is thereore needednot only to understand these fows but also to seek ways omanaging dwindling reserves more eciently.

Nutrients: How Do We Preserve

and Enhance the Fertility o Our

Soils while Exporting Ever Bigger

Harvests?

As yields increase, so do nutrient exports rom soil. Inthe United States, or example, the harvest o major cropsannually removes about 7.8 Tg o N (excluding N2–xingcrops—alala, soybean, and peanut), 2.3 Tg o P, and 6.7Tg o K, with removals increasing by roughly 1% per year(International Plant Nutrition Institute, 2010).

I reserves in soils are to be maintained, exportednutrients need to be replenished. One way to do that—anapproach we rely on ever more as yield demands increase—is to apply commercial ertilizers. As much as 40 to 60% oood produced in the United States and United Kingdomis due to ertilizer use, with even higher proportions in thetropics (Stewart et al., 2005). Erisman et al. (2008) estimatedthat ertilizer N accounted or the ood o 48% o the 2008global population.

We can no longer do without synthetic ertilizers. Buttheir supply depends on nite reserves o energy and ores(Jasinski, 2008; Ober, 2008; Cordell et al., 2009). They are

2 3

P h o t o o n t h e l e f t o r i g i n a l l y s u b m i t t e d w i t h a J o u r n a l o f E n v i r o n m e n t a l Q u a l i t y a r t i c l e b y W e s t o n e t a l . ( 2 0 0 8 ; 3 8 : 2 3 8 - 2 4 7 ) . P h o t o o n t h e r i g h t o r i g i n a l l y s u b m i t t e d w i t h a

n A g r o n o m y J o u r n a l a r t i c l e b y H a n n a e t a l . ( 2 0 0 8 ; 1 0 0 : 1 4 8 8 – 1 4 9 2 ) .




also a major input cost or armers, and i not used judi-ciously, they can contaminate air and water. Consequently,urther eorts are still needed to improve their eciency(Dobermann, 2007). For cereal crops, uptake in the yearapplied is typically <60% or N, P, and K, although suchestimates may not include nutrients retained in the soil(Snyder and Bruulsema, 2007).

Another aim is to recycle more eciently the nutrientsalready in ecosystems, notably those in manure. Globally,the N voided by animals rivals the amount added in ertil-izer, but only about 40 to 50% o excreted N is recoveredand only about hal o that is recycled to cropland (Oenemaand Tamminga, 2005). Nutrients in crop residues can also

be used more eciently, especially those in legume residues,which provide biologically xed N2 (Doran et al., 2007).

Nutrients, like soil, water, and biological resources, arelimited and need to be stewarded. For all sources, importedor recycled, the basic strategy is simple in concept—ensur-

ing that the nutrient supply is tightly tuned to plant needs,thereby aording adequate nutrition while minimizingleaks. But with the vicissitudes o nature—capriciousweather and variable soils, or example—we have not yet

been able to precisely synchronize nutrient availability withcrop needs.

Stewardship o nutrients can oten be improved byretuning existing practices: improved placement, timing,and orms o ertilizer, or example. But some inecienciesarise rom undamental ecological disconnects—the sureito manure nutrients ar rom their source, or example. Insuch cases, systems with entirely recongured nutrientfows may be needed. Always, the best approaches can

be ound by ollowing nutrients over the long term andthrough their lie cycle, rom initial entry to nal ate.

Energy: How Can We Manage

Our Lands to Accommodate

Increasing Demands?

Plant-based biouels have surged to prominence, as away o mitigating climate change while seeking energy

Climate Change: How Will It

Aect the Productivity and

Resilience o Our Soils?

Concentrations o greenhouse gases in the atmosphereare rising rapidly. Carbon dioxide concentration, once

security. The dominant processed biouel now is ethanol,mostly rom grain corn or sugarcane. In the United States,or example, more than 20% o corn yield is used orethanol (Tolleson, 2008). Producing grain-derived biou-els, however, is relatively inecient and could increaseCO2 emissions rom land use change (Fargione et al., 2008;Searchinger et al., 2008) or N2O emissions rom growing thecrops (Crutzen et al., 2008). Cellulose-based ethanol couldyield higher energy eciency, but technologies are not yetmature.

The growing demand to urnish eedstocks or biouelemphasizes the importance o careully evaluating ecologi-cal tradeos. I more C is removed or biouel, that leavesless or use as ood, uel, or soil C replenishment (Lal, 2009).Many other questions remain. How do biouel crops orplantations aect water use (Tricker et al., 2009; Karp andShield, 2008) or biodiversity (Wilcove and Koh, 2010)? Canthe greenhouse gas emissions rom growing these crops

be reduced (Crutzen et al., 2008)? What are the long-termeects o energy crops on salinity (Bartle et al., 2007) andother soil properties? Can the byproducts o bioenergy (e.g.,

biochar) be applied to improve soil quality and productivity(Gaunt and Lehmann, 2008)?

The dwindling reserves o cheap and relatively cleanenergy sources will aect ecosystems worldwide, both

by making energy more expensive and by expanding theharvest o biomass or energy use. Soil scientists will needto be alert and ar-sighted to ensure that these changes donot compromise the long-term health o ecosystems and tosee that gains in one acet o the environment (e.g., climatechange mitigation) do not induce losses elsewhere (e.g., soil

quality or biodiversity loss).

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about 280 μL L−1, now exceeds 380 μL L−1, and is increasing by almost 2 μL L−1 yr−1, mostly rom ossil uel combustion but also rom land use change (Canadell et al., 2007). Thisabrupt increase is projected to have long-lived eects on theglobal climate and biogeochemistry, aecting ecosystemsin many ways, both direct and indirect (IntergovernmentalPanel on Climate Change, 2007). For example: higher CO2 concentrations aect the photosynthetic rate; changes tolocal climates aect the adaptivity o plants, animals, andtheir pests; warming accelerates organic matter decay;altered precipitation patterns cause droughts or fooding;changes in weather intensity aect soil erosion; rising sealevels alter coastal ecosystems; thawing o northern soilsmay induce CH4 bursts; and shits in arable lands may posenew threats on newly cultivated soils as arming systemsmove or adapt. In short, projected changes will stressecosystems worldwide, sometimes leading to dysunctionand even positive eedback on climate changes (Ojima and

Corell, 2009).Because many o the threats rom climate change aect

the land, soil scientists will need to be at the oreront o cli-mate change research. First, we need to better predict, basedon a deeper understanding, how coming changes will aect

ecosystem unctioning. What will happen to the massivereserves o C stored in soils, wetlands, and tundra (David-son and Janssens, 2006; Schuur et al., 2009)? Or how willchanging climates alter N mineralization or corn in Iowa,soil organic matter in German orests, soil sediment load inthe Amazon estuary, and pest outbreaks in the Serengeti?

A second aim is to help design systems on managedlands that mitigate the threat o climate change by seques-

tering C in elds and orests, by curtailing emissions o CH4 and N2O rom armlands, and by providing eedstocks or

bioenergy. Soil scientists should ensure not only that thesepractices are eective in the short term, but also that theydo not jeopardize long-term ecosystem perormance.

Third, soil scientists will need to help prepare orchange. Many impending changes already have enoughinertia that some impact is inevitable. Perhaps the best wayo bracing or change (sometimes even beneting rom it)is to bolster the resilience o ecosystems, especially thosedominated by humans. This means identiying and protect-

ing the most ragile systems and envisioning new ones thatmight withstand and fourish in decades ahead.

Biodiversity: How Can We Better

Understand and Enhance the

Biotic Communities within and on

the Soil to Create More Resilient

and Fructuous Ecosystems?

Lie on earth occurs in a dazzling array, entwined byfows o nutrients and energy. Through the long eons, thesemyriad biota gradually evolve, some species being lost,others emerging. Recently, however, rates o extinction haveaccelerated (Scholes and Biggs, 2005) so that conserving bio-

diversity is now a priority (Cabrera et al., 2008).Soils are the oundations or the ecosystems that house

terrestrial biota, so preserving soils is oten a rst stepin preserving biodiversity (Lal, 2007). Furthermore, soilsthemselves hold an astounding abundance and variety oorganisms, many o which remain unidentied and unstud-ied (Giller, 1996; Wole, 2001; Barrios, 2007). Indeed, “soilsare one o the last great rontiers or biodiversity research”(Fitter et al., 2005).

Why is preserving biodiversity so important? First, ter-restrial biota drive many o the vital unctions perormed

by ecosystems, rom urnishing ood to ltering water todelivering pharmaceuticals (Daily, 1997; Hooper et al., 2005;

Fischer et al., 2006). The soils’ microbial and aunal commu-nities, although hidden and ill understood, quietly mediatecountless essential processes (Coleman et al., 2004; Wardleet al., 2004). Indeed, our eeble grasp o their services may

be the best reason or preserving them; without knowingexactly what they do, we cannot even be sure what we havelost when they vanish. Second, preserving biodiversityconers resilience and stability to ecosystems (Brussaard etal., 2007; Naeem et al., 2009). Although organisms perormoverlapping unctions, this redundancy provides stabilityand contingencies during disturbances and upheavals.

Because many of the threats

from climate change affect the

land, soil scientists will need to

be at the forefront of climate

change research.

6




I maintaining biodiversity is imperative, how does itaect the research we do? A rst aim, clearly, is to use newmethods (e.g., Zhang and Xu, 2008) to measure diversitywithin and on the soil. Ideally, measurements should beconducted at a continuum o scales, rom soil aggregateto the entire planet (Loreau et al., 2001; Brooks et al., 2006;Scholes et al., 2008), and also across time, rom days to de-cades. Broader scales also allow us to probe questions abouttradeos; or example, is more intensive cropland monocul-ture (sparse diversity) justied to spare uncultivated lands(rich diversity) elsewhere (Green et al., 2005)?

A second aim is to understand more clearly the links be-tween diversity and ecosystem perormance and resilience.We know enough to presume that biodiversity is critical butnot enough to explain the mechanisms and complex interac-tions by which these benets are conerred (Andrén andBalendreau, 1999; Wardle et al., 2004).

Third, we need to understand better how humans threat-

en (or enhance) biodiversity within and on the soil. Whicharming practices enhance diversity; which ones destroy it?What will be the infuence o proposed orestry practices onthe long-term soil biology? And how will impending globalchanges aect the countless communities o organisms thaturnish the ecosystem unctions on which we will dependinto the uture (Araújo and Rahbek, 2006)?

Recycling “Wastes”: How Can We

Better Use Soils as Biogeochemical

Reactors, Thereby AvoidingContamination and Maintaining Soil

Productivity?

Wherever we go and whatever we do, we leave behindwastes—rom households and cities, rom amily dinnersand amily arms. As our numbers grow and our consump-tion intensies, the volume o our reuse increases, and wiseuse o wastes becomes a bigger challenge.

Many problems o “waste” arise rom a linear viewo industrial processes: raw materials enter at one end,and products and wastes emerge at the other. This linearsequence creates two problems: depleted raw resources atone end; excess wastes at the other. What is needed, then,is a regenerative cycle (Pearson, 2007), where the “waste”

becomes input, a cycle that, mimicking nature, can continuewithout end.

Several examples may illustrate the opportunities. One isto nd ways o reusing byproducts o industrial processes—the excreta o ood and ber actories, the debris o sheriesand orestry, or example. A second challenge is to use morewisely the growing stockpiles o animal manure (Russelleet al., 2007). And a third is to learn how to recycle also ourown biological wastes, rerouting them back to the land romwhich they came.

Soils, the site o decay, are central to any regenerativesystem, and soil scientists will need to address some criticalquestions. What is the capacity o various soils to processwastes without harm to themselves or the water or air theyeed into? What is the ate in soils o toxins and biohazardsthat are applied with organic amendments (Alexander,1994)? Can we design systems that emphasize local recy-cling o byproducts, even in cities, avoiding long-distancetransport? In probing these and other questions, soilscientists may help redesign our arming, orestry, urban,and industrial systems to better convert “wastes” into

“resources.”Soils are not only agents o recycling, they themselves

benet rom the recycling. Decomposition in soil canimprove the soil physical structure, supply the soil andplants with nutrients, and oster an energy- and substrate-rich environment to host a diversity o biota (Barrios, 2007;Abiven et al., 2009). In the long term, however, inputs owastes need to be balanced by the soils’ capacity to recyclethem (Edmeades, 2003).

7

What is needed ... is a

regenerative cycle, where the

“waste” becomes input, a cycle

that, mimicking nature, can

continue without end.... Soils,

the site of decay, are central to

any regenerative system...

PhotobyPegg

yGreb(USDAARS)



Science


Our earth is one cohesively connected entity, yet woundsare inficted on the landscape locally: a armer’s eld, astand o orest, and a trickling stream. And healing o theearth also happens locally. The best way to manage the landvaries rom place to place, rom year to year. Because o themany local actors—physical, social, and ecological—thereare ew universal “best management practices.”

What is the way out o this dilemma—the need or a

global perspective, while tuning practices to local peculiari-ties? The solution may lie in crating a seamless under-standing across scales o space rom a soil aggregate tothe planet. With careul weaving, such a continuum acrossscales allows insights and ndings to be extrapolatedupward, rom the local to the global, and also downward,rom the planet to the neighborhood. Soil scientists areuniquely endowed to orge such a continuum because theobject o their study, soil, is itsel an unbroken skin stretch-ing across all terrestrial landscapes (and i we allow “soil”to include sediment, then, in act, it wraps the entire suraceo the planet).

This new way o looking at the world, in eect, al-lows a shiting o the boundaries o an ecosystem—rom a

handul o earth to the entire planet. A starting point may be to maintain and expand evolving global databases osoil, vegetation, and research ndings (Hartemink, 2008),making them accessible to all potential users, rom armer-villagers to scientists. And to see changes in soils, we alsoneed networks o long-term sites (Robertson, 2008; Richteret al., 2009)—numerous ecological sites, across biomes andland uses, sampled repeatedly to monitor how lands andtheir inhabitants change across decades. Although suchnetworks are already underway, many gaps remain, notablyin developing countries.

Ways to ease the pressures awaiting human society,we claim, are ounded in a better understanding o soils

(Fig. 1 ). How then do we, who claim to know the soil best,expand and apply our expertise? We oer here some initialthoughts, as seeds to urther ruitul conversations.

Reocus and Redouble Our Research Eorts

on the Questions Identifed

A rst aim is to intensiy our eorts to understand our biosphere, probing its unctioning with the intent o build-ing and preserving robust ecosystems, resilient enoughto fourish in the coming tempests. In some areas, such as

boreal orests and polar regions still relatively unscathed by direct human infuence, that means learning how the

systems behave in the hope o minimizing uture stresses.In others—intensively managed armlands, or example—itmeans looking or ways to reduce harm and imbue resil-ience while meeting the growing demands expected othem.

Such research should be directed, not rom the vantageo today, but rom that o our successors. I earth’s systemsare changing and much o our research will reach ruitiononly ater long years, we might best design our experimentswith an eye to how our landscapes will be when the nd-

Fig. 1. Some ways in which soils support societal aims,now and into the uture. The eight pillars correspondroughly to the issues addressed here.

Global Perspective: How Can We

Develop a Seamless Perspective

that Still Allows Us to Optimize

Management Practices or Local

Places, Wherever They May Be?8




ings emerge. This will demand all our oresight, to envisionour earth as it will be and steer our work accordingly.

More than one civilization has allen ater ailing tonurture soils and their unctions (Hillel, 1991). Soil erosionlikely hastened the decline o the Greek empire more than2,000 years ago because people did not understand the ir-reversibility o soil loss. Similarly, limited understanding osoil–water relations let lands in the Tigris and Euphratesvalleys saline and barren. More recently, huge amounts o Nwere lost rom Great Plains soils beore their native stockshad even been measured. Our task is to ensure that our ownunolding society, and that o our successors, does not alteror want o understanding its oundation—the soil.

Broaden Our Vision and Scope

To address the global issues conronting us, we willneed to broaden our purview. First, we will want to look

beyond soils to ecosystems, encompassing all living thingsand their physical environment and all the fows o energyand elements that connect them (Tansley, 1935). Second, wewill need to look beyond deliberately managed lands to all

biomes, emerging rom the agricultural sector, our comort-able cocoon, to oer expertise to other scientic disciplinesand to policymakers. Furthermore, soil scientists shouldlook beyond well-unded regions to encompass especiallypoorly studied areas (Huntingord and Gash, 2005); or

example, i uture environmental stresses will weigh mostheavily in developing countries (Millennium EcosystemAssessment, 2005), can we apply more o our expertisethere? Finally, we should see beyond the biophysical sci-ences to enold also the humanities—economics, sociology,philosophy, political science—even the arts. The biophysicalsciences alone will not resolve the awaiting stresses; i our

behavior, in the end, is the most critical threat and hope orplanetary health, then we may not make much headway inour science without also studying ourselves and reshapingour behavior (Lal, 2007; Jasano, 2007).

The real questions acing soil science—no less urgentthan merely producing more—have to do with soteninghuman impacts on the environment. Such eorts will de-mand new alliances, new synergies with diverse disciplines.But soil scientists have historical advantages here; the soilswe study already connect societies across geography andacross time. Have we exploited that integrative advantageenough?

Our ecosystems urnish or us countless services (Daily,1997). Many are tangible and sel-evident: ood, uel, andber; shelter or wildlie (and people); livelihood and placesto play. But others happen quietly, in the background, andalthough they may be invisible, such services are as essen-tial as the obvious ones. Can we, in the uture, study alsothese other services by linking our work with that o otherdisciplines?

Entice New ScientistsFor any species to survive and prosper, it must replenish

itsel. That applies also to soil scientists; and now, to ourperplexity, the prospects or numerical renewal sometimesseem a little gloomy. Most soil scientists today are “mature”(Collins, 2008) and, in many places, student enrollment insoil science courses has allen (Baveye et al., 2006; Har-temink, 2006; Hopmans, 2007). The mention o excitemento soil science to an undergraduate student may elicit a

blank stare.

One way to advance a “renaissance” (Hartemink andMcBratney, 2008) may be to redene what a soil scientist isand does. Where once soil scientists probed the soil seekingto elucidate processes there, now they study soil’s place in

the broader biosphere. Where once we retted about erodingsoil quality, now we ponder bigger questions o ecosys-tem resilience. Where once we congregated mostly amongourselves, now we mingle with others in diverse orums,disciplines, and issues (Bouma, 2009). In short, where oncewe looked downward onto and into the soil, now we lookupward and outward rom the soil, pondering the bio-sphere rom its oundation.

Another way to attract more students may be to illumi-nate and articulate, with greater passion, the grandeur oour questions. When listing the challenges with which we

In short, where once we lookeddownward onto and into the soil,

now we look upward and out-

ward from the soil, pondering the

biosphere from its foundation.

P h o t o c o u r t e s y o f J . K e l l e y , h t t p : / / S o i l S c i e n c e . i n f o



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wrestle, we might ourselves be surprised at their magni-tude, their urgency, the wild sense o curiosity they engen-der. The greatest enticement to emerging scientists may

be the chance to explore questions o our natural world,intensely ascinating, deeply relevant, and critical to soci-ety’s uture. Young students o chemistry and microbiologymight be surprised to nd that the most enticing researchtopics reside, not in the pure and tidy tubes and cultures othe laboratory, but in messy, mysterious soils.

Communicate Better

Soil science has an image problem, in part perhaps because ew outside our discipline appreciate the essentialplace o soil and the way it is enmeshed in the past anduture o society. Few link the abundance o vegetables intheir local grocery to healthy soils in Caliornia. Few stopto ponder that what they choose to eat might aect soil in a

distant landscape. And ewer still see that maintaining soilsis not just a question o ood but also o broader societalaims: security, justice, and peace (Lal, 2008).

Can we talk to others about soil science with morepassion and clarity? We might start by celebrating morevigorously our past achievements. We have already madesubstantive gains in many o the questions enumeratedabove. For example, global land productivity has more thandoubled in the past hal century (Alston et al., 2009), in partthrough better management o soils. Although poverty andhunger persist, more people are now better ed than ever

beore. Freed rom scrabbling daily or ood, most peopleacross the planet can enjoy social, emotional, intellectual,and economic pursuits that are the hallmarks o a civilizedworld. Another example: we have learned ways o conserv-ing soils in the ace o winds and water that once eroded thelands; one such practice—no-till—is now used eectivelyon arms worldwide (Hobbs et al., 2008). How many knowo these achievements?

We are a lucky lot, we who scratch about in the earth,trying to uncover its mysteries, searching or new hope inthe ace o ominous threats. Our good ortune and our sim-mering excitement, sadly, may not always erupt spontane-ously rom the papers we write and the text we fash onscreens. Our highest aim, then, may be to let our audiencesin on the joys o our exploring. Our noblest task, and themost rewarding, may be to nd better ways o express-

ing our delight and wonder in the secrets we are slowlyunearthing, and o how our renewed acquaintance with theland can oer hope or coming generations.

Acknowledgments

This review was conceived and submitted as an activityo the Emerging Issues in Soil Science Committee (2008) oSSSA. We acknowledge the creativity o Sheila Torgunrudin drating Fig. 1.

Soil Science Society of America

Celebrates 75th AnniversaryThe Soil Science Society o America (SSSA) is

celebrating its 75th Anniversary in 2011, and also the

75th anniversary o its peer-reviewed journal, the Soil

Science Society of America Journal (SSSAJ).

Founded in 1936, SSSA supports peer-reviewed

publications, an Annual Meeting, science policy

activities, and the Certifed

Proessional Soil Scientist

Program. Today, SSSA

continues to help its

members advance the feld o

soil science through outreach

to teachers, undergraduateand graduate students, and

members around the world.

“During our 75-year history, the Soil Science

Society o America has had many accomplishments.

From our peer-reviewed journals, Annual Meeting,

and educational outreach, we have much to

celebrate,” says SSSA President Charles W. Rice,

Kansas State University. “We look orward to the next

75 years in SSSA history, as the importance o the

soil ecosystem moves to the oreront o discussions

about climate change, ood security, water quantity

and quality, contamination, and human health.”

SSSA recently completed its assessment o thegrand challenges acing the soil science discipline,

identiying the most critical uture research needs

in soil science: climate change; ood and energy

security; waste treatment and water quality; and

human and ecosystem health. For more inormation

on the grand challenges in soil science, including the

ull list o short-, medium-, and long-term research

goals, visit: www.soils.org/about-society/grand-

challenges.

SSSA is planning several anniversary activities

throughout 2011. A national outreach plan is being

launched to increase awareness o the importance o

soils and the soil science proession and will continue

throughout 2011. A renewed and expanded eortto educate K-12 students about soil science is also

being launched in 2011. Anniversary celebrations will

culminate at the 2011 Annual Meetings, 16–19 Oct.

2011 in San Antonio, TX. For more inormation on

the Annual Meetings, visit www.acsmeetings.org. To

celebrate its anniversary, SSSAJ will publish historical

perspectives throughout 2011. For more inormation

on the journal, visit www.soils.org/publications/sssaj.




H. H. Janzen, Agriculture and Agri-Food Canada, LethbridgeResearch Centre, Lethbridge, AB, Canada; P.E. Fixen, Interna-

tional Plant Nutrition Institute, Brookings, SD; A.J. Franzlueb- bers, USDA-ARS, Natural Resource Conservation Center,

Watkinsville GA; J. Hattey, Plant and Soil Science Department,

Oklahoma State University, Stillwater; R.C. Izaurralde, JointGlobal Change Research Institute, Pacifc Northwest National

Laboratory, and, University o Maryland, College Park; Q.M.Ketterings, Department o Animal Science, Cornell University,

Ithaca, NY; D.A. Lobb, Department o Soil Science, University o Manitoba, Winnipeg, MB, Canada; and W.H. Schlesinger,

Cary Institute o Ecosystem Studies, Millbrook NY.

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