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Editorial

Landscape ecology, cross-disciplinarity, and sustainability science

Landscape ecology has been widely recognized asa highly interdisciplinary science of heterogeneity.In general, heterogeneity refers to a multiscaledstructure composed of intertwining patchiness andgradients in space and time. It is the revelation ofthe importance of heterogeneity that makes thelandscape perspective so pervasively relevant toecology at different organizational levels as well asearth sciences across a broad range of spatialscales. Heterogeneity may be regarded as anessential cause and consequence of diversity andcomplexity in both natural and social systems, andthus plays a key role in dealing with complexity intheory and practice. In a recent review, Turner(2005) concluded that landscape ecology ‘‘is wellintegrated with ecology’’ and ‘‘has matured.’’ Shesuggested that landscape ecology should continueto focus on spatial heterogeneity and the rela-tionships between pattern and process.

Landscape ecology has also been considered as‘‘a holistic and transdisciplinary science of land-scape study, appraisal, history, planning andmanagement, conservation, and restoration’’(Naveh and Lieberman 1994). The heterogeneity-centered view has often been criticized for beingtoo ‘‘analytic’’ or simply inadequate, and someeven call for a paradigm shift ‘‘away from anecological focus for the discipline to a moreanthropocentric one, in which landscapes and theecosystems associated with them are viewed as aresource that provides a range of goods and ser-vices for people’’ (e.g., Potschin and Haines-Young 2005). One may argue, however, it is theecological focus that has driven most of the theo-retical and empirical developments of landscapeecology in the past two decades, which conse-quently has transformed the field from a regionalapplied research area to a globally establishedmainstream science. To many, landscape ecologyis after all still ‘‘ecology’’ no matter how ‘‘land-scape’’ is defined. Evidently, although landscapeecologists seem to converge on the desire for aunified landscape ecology, their ideas still divergesignificantly as to how to achieve this goal. So,

how do we reconcile these seemingly contrastingviews?

Seeking commonalities, not just differences

The different views are rooted in the well-notedEuropean versus North American traditions inlandscape ecology (Wiens 1999; Bastian 2001; Wuand Hobbs 2002, 2006). It is true that the twotraditions differ in some significant ways: the for-mer has been characterized by a society-centeredholistic view that focuses on solution-driven re-search, whereas the latter is dominated by a bioe-cology-centered spatial view that focuses onquestion-driven studies. This dichotomy, however,is an oversimplification of the reality. Indeed, wemay have exaggerated the differences and over-looked underlying commonalities between thesetwo dominant perspectives. For example, hetero-geneity, pattern-process relationships, and scaleissues are essential to all natural and social sci-ences, and they are powerful unifying concepts fordeveloping an integrative science of landscapes.The simplistic dichotomy also obscures the factthat landscape ecologists around the world havelong been cognizant of the importance of humansin influencing landscapes. The differences hingemainly on the ways these anthropogenic influencesare incorporated in research, ranging from treatinghumans as ‘‘one of the factors creating andresponding to spatial heterogeneity’’ (Turner et al.2001) to considering the landscape as a ‘‘totalhuman ecosystem’’ (Naveh and Lieberman 1994).

In addition, it is more than just intriguing tonote that both perspectives can be traced back toCarl Troll’s (1939) original definition of landscapeecology, i.e., ‘‘the study of the main complexcausal relationships between the life communitiesand their environment’’ which ‘‘are expressedregionally in a definite distribution pattern (land-scape mosaic, landscape pattern)’’ (Troll 1971).The North America perspective on the interrela-tionship between pattern and process is not only

Landscape Ecology (2006) 21:1–4 � Springer 2006

DOI 10.1007/s10980-006-7195-2

consistent with Troll’s definition, but also abreakthrough in realizing Troll’s aspiration tointegrate the geographical and structural approachwith the ecological and functional approach. Onthe other hand, landscape research in Europe hasepitomized the idea of landscape as a human-dominated gestalt system, which was evident in thepioneering work by Troll and other holistic land-scape scientists. These two perspectives are notnecessarily contradictory but complementary (Wuand Hobbs 2002, 2006).

A hierarchical and pluralistic view of landscape

ecology

The current discourse seems to have much to dowith how one views cross-disciplinarity (multi-,inter-, and transdisciplinarity) and the relationshipof landscape ecology to the emerging sustainabilityscience. Here I suggest that a hierarchical, plural-istic framework for landscape ecology (Figure 1)may help facilitate the integration between thedifferent perspectives and approaches. A generalassumption used here is that unification is not tomake certain views more prominent by diminish-ing others, but rather to join different perspectivescomplementarily to produce a whole that is largerthan the sum of parts.

Terms related to cross-disciplinarity arenumerous, and their definitions are diverse andoften confusing if not contradictory. A lucid dis-cussion of these terms, however, is found in Tressand Tress (2005): multidisciplinary research in-volves multiple disciplines that interact onlyloosely with a shared goal but parallel disciplinaryobjectives; interdisciplinary research involves mul-tiple disciplines that interact closely to achieve acommon goal based on a concerted framework;and transdisciplinary research has both close cross-disciplinary interactions and participation fromnon-academic stakeholders and governmentalagencies guided by a common goal. I suggest thatcross-disciplinarity may be discussed in differentdomains, such as within biological sciences, amongnatural sciences, or across natural and social sci-ences. In any case, landscape ecology is both inter-disciplinary and transdisciplinary. Furthermore,the interdisciplinarity and transdisciplinarity oflandscape ecology may be interpreted in a hierar-chical and pluralistic way. ‘‘Hierarchical’’ here

emphasizes the varying degrees of cross-disciplinaryinteractions and the relativity of the definition ofdiscipline, while ‘‘pluralistic’’ refers to the necessityto involve different disciplines and perspectives.

In this hierarchical and pluralistic framework,various perspectives and approaches correspondto, or span across, different levels in the hierarchyof cross-disciplinary integration (Figure 1). Land-scape ecological studies exhibit varying degrees ofcross-disciplinarity that are commensurate withspecific research questions and goals. In general,moving from the interdisciplinary base towardsthe transdisciplinary top of the pyramid, the de-gree of integration among disciplines, prominenceon humanistic and holistic perspectives, and directrelevance to societal issues all increase. Note thatthis does not suggest that we move ‘‘away from anecological focus,’’ but rather increasingly integrateit with the social and economic fabrics of thelandscape to meet the needs for understanding andresolving landscape management and planningproblems. Consequently, the dominant researchmode is gradually shifting from plot-based andquestion-driven studies to place-based and solu-tion-driven investigations, with increasing subjec-tivity and uncertainty in system description andprediction. Research findings tend to be moreidiosyncratic as they are closely tied to the envi-ronmental, economic, and socio-cultural particu-lars of the landscape or region. Researchmethodology also shifts its emphasis along thespectrum. While falsificationistic and hypothetico-deductive methods, rooted in the Poperian phi-losophy of science, are powerful and preferable forproblems that are amiable, alternative scientificmethodologies (see Pickett et al. 1994) thatemphasize the value of confirmation and inductivereasoning are increasingly needed as we move to-wards the transdisciplinary end.

Landscape ecology and sustainability

Sustainability science is a new kind of science thatfocuses explicitly on the dynamic interactions be-tween nature and society (National ResearchCouncil 1999; Kates et al. 2001; Clark and Dick-son 2003; Reitan 2005). It involves ‘‘the cultiva-tion, integration, and application of knowledgeabout Earth systems gained especially from theholistic and historical sciences (such as geology,

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ecology, climatology, oceanography) coordinatedwith knowledge about human interrelationshipsgained from the social sciences and humanities’’(Reitan 2005). It is fundamentally important torealize that ‘‘successfully sustainable human soci-eties must… be as attuned as possible to their localand regional environments, their geoecologicalsupport systems; lifestyles must be adapted to theecosystems in which societies live…, and governingpolicies each adjusted to fit their area, not a singledominant culture or way of living spread acrossthe globe’’ (Reitan 2005). Sustainability scienceaddresses issues such as self-organizing complex-ity, vulnerability and resilience, inertia, thresholds,complex responses to multiple interacting stresses,adaptive management, and social learning, and iscommitted to place-based and solution-driven re-search encompassing local, regional, and globalscales (Kates et al. 2001; Clark and Dickson 2003).

Of particular relevance to landscape ecology is theemerging ‘‘land-change science’’ (sensu Rindfusset al. 2005), a critical component of sustainabilityscience which focuses on observing and monitor-ing land use and land cover change (LUCC),assessing the impacts of LUCC on ecosystemprocesses, goods and services, and understandingthe biophysical and socioeconomic mechanisms ofLUCC.

As shown in Figure 1, towards the transdisci-plinary end of the spectrum landscape ecology isincreasingly related to sustainability science intheory and practice. Overall, landscape ecologycan contribute significantly to the development ofsustainability science on several grounds. First ofall, the human landscape (or region) may be con-sidered as a basic spatial unit for studying andmaintaining sustainability because it represents thesmallest scale above which nature-society interac-

Figure 1. A hierarchical and pluralistic view of landscape ecology and its relationship to sustainability science.

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tions can be meaningfully addressed. Second,landscape ecology provides a hierarchical andintegrative ecological basis for dealing with issuesof biodiversity and ecosystem functioning at mul-tiple scales. Third, landscape ecology has alreadydeveloped a number of holistic and humanisticapproaches to studying nature-society interac-tions, which are quite relevant to sustainabilityscience. Fourth, landscape ecology offers theoryand methods for studying the effects of spatialheterogeneity or biophysical and socioeconomicconfigurations on sustainability. Fifth, to developa rigorous science of sustainability, it must bequantified whatever sustainability means, and asuite of methods and metrics in landscape ecologycan be used for this purpose. Finally, landscapeecology provides both theoretical and methodo-logical tools for dealing with scaling and uncer-tainty issues that are fundamental to most nature-society interactions (Wu et al. 2006).

There is little doubt that landscape ecologyshould and will make significant contributions tosustainability science. It seems not only appropri-ate but also necessary to consider landscape ecol-ogy part of the scientific core of sustainabilityscience. However, the success and credibility of aninterdisciplinary or transdisciplinary science arenot likely to be achieved without solid disciplinarybases. An ecological focus has been and will con-tinue to be essential for the development of land-scape ecology which, indeed, is a heterogeneousscience of heterogeneity.

References

Bastian O. 2001. Landscape Ecology: Towards a unified disci-

pline? Landscape Ecol. 16: 757–766.

Clark W.C. and Dickson N.M. 2003. Sustainability science:

The emerging research program. Proc. Nat. Acad. Sci. (USA)

100: 8059–8061.

Kates R.W., Clark W.C., Corell R., Hall J.M., Jaeger C.C.,

Lowe I., McCarthy J.J., Schellnhuber H.J., Bolin B., Dickson

N.M., Faucheux S., Gallopin, G.C., Grubler A., Huntley B.,

Jager J., Jodha N.S., Kasperson R.E., Mabogunje A., Mat-

son P., Mooney H., Moore B.III, O’Riordan T. and Svedin

U. 2001. Sustainability Science. Science 292: 641–642.

National Research Council. 1999. Our Common Journey: A

Transition Toward Sustainability. National Academy Press,

Washington D.C.

Naveh Z. and Lieberman A.S. 1994. Landscape Ecology:

Theory and Application. Springer-Verlag, New York.

Pickett S.T.A., Kolasa J. and Jones C.G. 1994. Ecological

Understanding: The Nature of Theory and the Theory of

Nature. Academic Press, San Diego.

Potschin M. and Haines-Young R. 2005. Rio+10, sustain-

ability science and Landscape Ecology. Landscape Urban

Plan. doi:10.1016.

Reitan P.H. 2005. Sustainability science – and what’s needed

beyond science. Sustainability: Science, Practice, & Policy 1:

77–80.

Rindfuss R.R., Walsh S.J., II B.L.T., Fox J. and Mishra V.

2005. Developing a science of land change: Challenges and

methodological issues. Proc. Nat. Acad. Sci. 101: 13976–

13981.

Tress G., Tress B. and Fry G. 2005. Clarifying integrative re-

search concepts in landscape ecology. Landscape Ecol. 20:

479–493.

Troll C. 1939. Luftbildplan and okologische bodenforschung.

Zeitschraft der Gesellschaft fur Erdkunde Zu Berlin: 241–

298.

Troll C. 1971. Landscape Ecology (Geoecology) and Bioge-

ocenology–A Terminology Study. Geoforum 8/71: 43–46.

Turner M.G. 2005. Landscape ecology: What is the state of the

science? Ann. Rev. Ecol. Syst. 36: 319–344.

Turner M.G., Gardner R.H., and O’Neill R.V. 2001. Land-

scape Ecology in Theory and Practice: Pattern and Process.

Springer-Verlag, New York.

Wiens J.A. 1999. Toward a unified landscape ecology Issues in

Landscape Ecology. In: Wiens J.A. and Moss M.R. (eds),

International Association for Landscape Ecology. Snowmass

Village, USA, pp.148–151.

Wu J. and Hobbs R. 2002. Key issues and research priorities in

landscape ecology: An idiosyncratic synthesis. Landscape

Ecol. 17: 355–365.

Wu J. and Hobbs R. (Eds.) 2006. Key Topics in Landscape

Ecology. Cambridge University Press, Cambridge. UK.(in

press)

Wu J., Jones K.B., Li H. and Loucks O.L. (Eds.) 2006. Scaling

and Uncertainty Analysis in Ecology: Methods and Appli-

cations. Springer, Dordrecht, The Netherlands.

JIANGUO (JINGLE) WU

School of Life Sciences and Global Institute ofSustainability

Arizona State UniversityTempe, AZ 85287

(E-mail: Jingle.Wu@asu.edu)

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