Ciencia Ergo Sum ISSN: 1405-0269 [email protected] Universidad Autónoma del Estado de México México

Calderón-Contreras, Rafael Between and Scientific Knowledge: How Might Dryland Environments Challenge Ideas Regarding Ecological Dynamics? Ciencia Ergo Sum, vol. 17, núm. 1, marzo-junio, 2010, pp. 81-87 Universidad Autónoma del Estado de México Toluca, México

Available in: http://www.redalyc.org/articulo.oa?id=10412443011

How to cite Complete issue Scientific Information More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Between Environmental Policy and Scientific Knowledge: How Might Dryland Environments Challenge Ideas Recepción: 23 de abril de 2009 Aceptación: 7 de diciembre de 2009 Regarding Ecological Dynamics? * Postgraduate Researcher at the University of East Anglia, Norwich, United Kingdom. Correo electrónico: Rafael Calderón-Contreras* [email protected] The author wishes to thank Juan Carlos Barron, Citlalli Becerril and Rafael Guerrero from the The desert teaches by taking away School of International Development of the Arab Proverb University of East Anglia for their valuable insights and two anonymous referees for their accurate comments and suggestions on earlier versions of the paper. Special thanks to Tomas Chaigneau for his help on correcting the final version of this paper.

Entre la política ambiental y el conocimiento científico: cómo Abstract: The main objective of this essay is to analyze how the rise of ambientes desérticos y semidesérticos desafían ideas sobre perspectives towards dryland environments challenges traditional ideas dinámicas ecológicas about ecological dynamics. To reach that goal, the essay is divided in three Resumen. El objetivo principal de este trabajo es analizar cómo las sections: the first part analyzes the characteristics of and perspectivas acerca de los ambientes semidesérticos y desérticos desafían the way in which dryland environments challenge the traditional concepts las ideas tradicionales acerca de las dinámicas ecológicas. Para alcanzar of loading capacity, the area- postulate and the biodiversity- este objetivo, el artículo se divide en tres partes: la primera analiza las stability postulate. The second part will analyse the rise of “new ecology” características de la ecología de sistemas y la forma en la que dichos and how concepts from non-equilibrium ecology diverge from those in the ambientes disputan los conceptos tradicionales de capacidad de carga conventional ecology systems. The third part considers some features of y los postulados de área-biodiversidad y estabilidad. La segunda parte dryland environments in which this conceptual shifting has been evident; analiza el resurgimiento de la “nueva ecología” y cómo los conceptos this part highlights the ecological postulates adopted on policy design and de no-equilibrio divergen de aquellos pertenecientes a la corriente implementation regarding management, administration and support for más convencional de ecología de sistemas. Finalmente se consideran dryland environments. algunas características de los ambientes semidesérticos y desérticos que Key words: dryland environments, , area-biodiversity evidencian dicha dicotomía conceptual; esta sección busca acentuar postulate, stability, new ecology. los postulados ecológicos adoptados en el diseño e implementación de políticas en torno al manejo, administración y conservación de ambientes semidesérticos y desérticos. Palabras clave: ambientes desérticos y semidesérticos, capacidad de carga, area-biodiversidad, estabilidad, nueva ecología.

Introduction place, elaborating in the way in which different ecological systems cope with degradation and global environmental In 1987 the United Nations Environmental Programme change. The case of dryland environments is central to the (u n e p ) stated that 27 million hectares of productive study of ecological dynamics; firstly, because the observed were being lost to deforestation each year; according to that trend of desertification has been supported and used as a ge- estimate, all productive land on the planet would disappear neral discourse for diverse International Funding Institutions in 200 years time (Thomas, 1993; Swift, 1994). To reach such (i f i s) and Big Non-Governmental Organizations (bin g o s); a conclusion, an extensive array of academic research took and secondly, because dryland environments degradation

CIENCIA ergo sum, Vol. 17-1, marzo-junio 2010. Universidad Autónoma del Estado de México, Toluca, México. Pp. 81-87. 81 Ci e n c i a s So c i a l e s has been considered a global environmental problem as a features of dryland environments in which this conceptual result of mismanagement and human activities that lead to shifting has been evident; this part aims at highlighting the an irreversible ecological change through desertification (Illius perspective of the local population, government and IFIs and O’Connor, 1999; Larsen, 2003). ‘Overgrazing’ as a threat regarding management, administration and support for to global was embedded in the environmental dryland environments. doctrine adopted by different governments decision-makers, development practitioners and institutions to deal with issues 1. Systems Ecology: The Conventional Perspective of desertification (Sullivan, 2000; Sullivan and Rhode, 2002; Warren, 1995). Discourses about encroaching deserts, deser- The main precept of systems ecology is that environments tification, and as means of socio-political tend toward equilibrium state and temporal and spatial and economical struggles became the basis for policy imple- homogeneity characterized by mechanical regularity (Zi- mentation along the late twentieth century (Semple, 1971; mmerer, 1994; Sullivan and Rohde, 2002). Systems eco- Grainger, 1983; u n e p , 1992). logists hold that for each environment there is a process These statements based on traditional ecological postulates of niche specialization, in which every organism plays an fulfilled the interests of colonial and national governments, important and unique ecological role (Zimmerer, 1994; international aid donors, specially United Nations (u n ) Adler, 2000). This idea helped to create a narrative in which agencies; and some scientists that, adopting the ideas of the the modification of the role of ecological components in conventional systems ecology, and have been justifying their dryland environments lead to desertification, and that this interventions and policies by arguing that land degradation modification is encouraged by human activities particularly and desertification have broken the fragile ecological equili- overgrazing in communal forms of land tenure (Sullivan brium of dryland environments (Ellis, Coughenour and Swift, and Rohde, 2002; Blaikie, 2006). 1993; Adger, et al 2001; Sullivan, 1996). Recent research about The ecological theory that supported these mainstream the natural fluctuation in dryland vegetation communities ideas was based on the ‘succession theory’ of Clements and the management of its (Behnke, Scoones, (1916; in Warren 1995), in which vegetation ecologist argue and Kerven 1993; Thomas, 1993; Warren, 1995), added to that each organism reaches a climax that leads to the decline the rising of “new ecology” postulates; which challenges the of the specie (ibid.). Later, in 1930, following the work of traditional ideas about a which tends to equilibrium, Malthus (1798), the population growth models gave origin stability and balance (Botkin, 1990; Zimmerer, 1994). to the concepts of intrinsic growth rate and carrying capa- The main objective of this essay is to analyze how rising city, describing the supposed stable features of ecological of perspectives towards dryland environments can challenge dynamics (Behnke, Scoones, and Kerven 1993; Scoones, traditional ideas about ecological dynamics. By no means 1999:482). By 1950, established the basis does this essay aim at providing new conceptual or meth- of ideas that described natural environments as odological frameworks on ecological studies. Its purpose is complex networks with stable and defined interchange of to highlight the theoretical and conceptual underpinnings and nutrients (ibid.). Finally, conservation , that ecology has brought regarding dryland environments’ based on the principles of island (McArthur management, and the consequent policy implementation. It and Wilson, 1967; in Scoones, 1999) represents another is necessary therefore to analyze to what extent research and tendency of ecological theory in which equilibrium plays a programmes regarding dryland environments have adopted central role. The debate about the role of applied biology the postulates of the new ecology of non-equilibrium and regarding equilibrium in ecological dynamics came to a how this conceptual shift can lead to a better understand- point whereby the scientific rationality was rarely being ing of terms as desertification and dryland degradation. To tested (Margules, Higgs and Rafe 1982; Zimmerman and reach that goal, the essay is divided in three parts: the first Bierregaard 1986). Assumptions about Homogenous one analyzes the characteristics of systems ecology and the (Margules, 1982), unsubstantiated turnover rates way in which dryland environments challenge traditional and extinction rates (Boecklen and Simmberloff, 1987), concepts of carrying capacity, the area-biodiversity postulate bio-geographic corridors (Simberloff and Cox 1987), and the biodiversity-stability postulate. The second part will species reserves (Salwasser, 1986), among others (See analyse the rise of the “new ecology” and how concepts Orians, 1986 and Salwasser, 1986) became the buzzwords of non-equilibrium ecology diverge from the ones in con- in mainstream policy documents, and approaches to eco- ventional systems ecology. The third part considers some logical dynamics.

82 Ca l d e r ó n Co n t r e r a s R. Be t w e e n Environmental Po l i c y a n d Scientific Kn o w l e d g e : Ho w Mi g h t Dr y l a n d ... Ci e n c i a s So c i a l e s

These ideas and theories furthermore became a guide for environment, and assumes that the higher the specialization the management of diverse environments, and the findings of the organisms, the higher the biological diversity, and as of scientists attached to this epistemological content, gave a consequence, greater environmental stability (ibid.). Mo- raise to policies and practices of conservation based on reover, this reasoning implies that the equilibrium between three main postulates: carrying capacity, area-biodiversity specialization and biodiversity is an evidence of temporal postulate and biodiversity-stability postulate. stability. The influence of this postulate is often related The postulate of generalizing carrying capacity holds that to the implementation of crop varieties and management a given environment exists in equilibrium with a certain systems of semi-arid environments that supposed to ensure population of organisms, and when an environment is stability in the long term; however, according to Zimmerer overpopulated, consequently degradation and collapse are (1994:114): “Niche specialization is not somehow immuta- generated (Zimmerman and Bierregaard, 1986; Zimmerer, ble and given; its must be demonstrated rather 1994). These assumptions are related to an exponential than assumed”. population growth, and assume a temporal and spatial The given assumptions contributed to the perception of heterogeneity. Dryland environments challenge these ideas ecosystems as rigid and isolated structures, which compo- by demonstrating that under unpredictable disturbances as nents tend to equilibrium and internal homogeneity; for a drought, the rate of population growth can be temporally many years this concept constrained ecological studies modified (Thomas 1993; Warren, 1995). For instance, ba- and was characteristic of the plans and programs imple- sed on a study of long-term change in Machakos District, mented for their protection (Sullivan, 1996). However, Kenya, it was shown that degradation is not inevitable in new theoretical approaches are beginning to emphasize African dryland environments (Mortimore and Tiffen, non-equilibrium, instability and fluctuations in biophysical 1994). These kinds of empirical conclusions draw atten- environments rather than focus on their components and tion to ideas of loss, desertification and dryland their protection (ibid.). management as coming from ‘snap-shot’ and short-term landscape observations, and by broader visions of dryland 2. The New Ecology: the Non-Equilibrium environments, without taking into account the interface Concepts between population distribution and ecosystems (Fairhead and Leach 1996; 2000). Since the 1980s, there has been an empirical and theoretical Furthermore, the spatial distribution of the population shift in the concepts of ecology; the traditional ideas wi- in dryland environments is not stable in a single place, the thin systems ecology have been challenged by an emerging nomadic movement of organisms responds as well to the and interdisciplinary term: “new ecology” (Botkin, 1990; variation of geographical features (Warren, 1995). This Behnke, Scoones, and Kerven 1993; Zimmerer, 1994; Sco- characteristic of dryland environments is directly related ones, 1999). According to Borkin (1990:9) “[…] decisions to the second postulate: the area-biodiversity relations, in about managing nature were based on ideas that were clearly which asserts that “…biodiversity is a direct function of contradicted by facts, yet those who continued to advocate area (island size) and of isolation with respect to similar those outdated policies were acquainted with the facts; in my habitats […] area becomes the key predictor of biodiver- own field of ecology, those same ideas dominated, yet the sity: the larger the area the better” (Zimmerer, 1994:113). facts that contradicted them were gathered by ecologists”. Recent studies have shown that environmental conditions The of the new ecology postulates represented in dryland environments are not regular in time and spa- (and still represents) a challenge to not only the scientific ce; variations in factors such as regional biogeography, rationale previously discussed, but also brought light on environmental heterogeneity, migration capacities among policy issues that were based on those aspects of traditional organisms, stational whether conditions, etc. can modify ecological thinking. the relationship biodiversity-area (Botkin, 1990; Warren, For instance, the new ecology proclaims opposition to 1995; Adger, et al., 2001). the idea of stability of ecological systems basing its pre- The third postulate of systems ecology assumes that the cepts in three main concepts: multiple stable states, chaotic relations of biological diversity and stability are inextricable dynamics and non-equilibrium systems (Scoones, 1999). and determinate (Ellis, Coughenour and Swift, 1993; Marga- Thus, these concepts challenge the findings and precepts lef, 1968; In: Zimmerer, 1994). This perspective highlights of systems ecology, and therefore, due to the rising ac- the importance of the role that each organism plays on their ceptance of new ecology terms, the previous studies and

CIENCIA ergo sum, Vol. 17-1, marzo-junio 2010. 83 Ci e n c i a s So c i a l e s environmental assessments may be discussed. According policies and programmes directed to protect and manage to Thomas (1993:318), “[due to the introduction of this dryland environments must recognize its instability and new paradigm,] natural fluctuations in dryland vegetation leaving behind the neo-Malthusian discourse communities caused by inherent environmental instability and the precepts that consider the environment as an equi- need to be distinguished from degradation of the librated and stable system (Adger, et al, 2001). Studies in caused by human activities”, and also suggest that pre- African settings show that dryland environments are able vious assessments of desertification in the world may have to recover quickly from drought once the or overestimated by a factor of three (ibid.). The implication pressures return to more normal levels (Bie, 1992). “Many of these assumptions could lead to a new understanding development efforts disregard this resilience. Large-scale of dryland environments and the problems that are facing, tree planting projects, restocking schemes, develo- such land degradation and desertification. pment of energy sources alternative to firewood/charcoal, The new ecology concepts also involve a new notion of or the construction of road networks to facilitate delivery time; while systems ecology takes into account cyclical en- of relief supplies, may therefore be founded on erroneous vironmental variations, the new ecology takes as reference assumptions” (ibid.: 5). Furthermore, the resilience of historical time, making emphasis on irregular periodicity of dryland environments has demonstrated a central role in process that modify the regular features of the ecological understanding global environmental change. Recent studies dynamics (Christensen, 1989; Swift, 1994). The frequency have shown that policies regarding the struggle of human and spatial magnitude of natural disturbances have been settlements in dryland environments have not taken into seen as an important part of ecological dynamics more account the resilience of these systems, leading to inaccurate often than before; therefore, terms as land degradation and empirical evidence (Ramsey, West and Norton, 2008). This desertification began to be reassessed. For instance, after problem has created policies with questionable outcomes an exceptionally high rainfall period in the 1950s, the term and secondary consequences related to natural ‘desertification’ arose importantly due to the droughts in management and poverty reduction (ibid.). the 1970s and 1980s, becoming a priority problem for many Despite the arising of the concepts mentioned above, the international aid donors and governments (Adger, et al, 2001). majority of international donors, funding institution, gover- More recently, and based on the parameters of the new eco- nments and n g o s, continue using the concepts and precepts logy studies suggests that these periods of variability indicate of the old paradigm; as a consequence, the policies and that dryland environments have dynamic processes tending programmes are often based in overestimated information to the non-equilibrium (Sullivan, 1996). Natural fluctuations (Ellis, Coughenour and Swift, 1993; Thomas, 1993; Warren, as droughts and rainy periods indicate the normal variability 1995). The results of this erroneous information repeatedly of these environments, rather than the exclusive result of follow the interests of these decision makers, while pasto- human activities (ibid.). Empirical evidence about these ralists, small holders and subsistence farmers do not receive natural fluctuations and their role on interpreting landscape benefits from those actions (Adger, et al. 2001). dynamics and the policies to cope with it are growing in importance and recognition (See Fairhead and Leach, 1990; 3. Shifting the Paradigm: the Relevance of Drylands 2000 and Illius and O’Connor, 1999). The consequences of this shift in ecological dynamics conceptualization have origi- The assumptions of new ecology that highlight natural nated a deep reassessment of past estimates of the extent of variability in ecological dynamics, also take into account desertification that assert that between two thirds and three the human presence as a modifying agent of the environ- quarters of the dryland environments of the world had been ment (Adger, 2000). The relationship between social and decertified u( n e p , 1992). , moreover, have deep impacts on the Another term often used to describe some properties of conservation or degradation of any ecosystems under the new ecology perception is resilience. (ibid.). Furthermore, the new paradigm implies that protec- Resilience is the capacity of a system to absorb internal tion and management strategies must be carefully adapted and external perturbations and recover itself; is the ability to the permanent disequilibrium characteristics of dryland to maintain a steady ecological state (Pimm, 1991; Behnke, environments (Bie, 1992; Behnke, Scoones, and Kerven Scoones, and Kerven 1993; Holling, et al 1989; in: Adger, 1993; Warren, 1995). Nevertheless, the implementation 2000). The variability of dryland environments represent an of these strategies based on the old paradigm of systems example of the resilience of ecosystems; therefore, studies, ecology have found support in three main bodies:

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...a) ecologists who believed in Clement’s (1916) model of suc- 5. Drylands environments and the ‘fight’ against cession and ; b) economists who believed in desertification Hardin’s (1968) concepts of the ‘tragedy of the ’; and c) authoritarian administrations which saw pastoralist as backward With the main purpose of estimating the extent of land and destructive” (Adger, 2000; Sullivan and Rohde, 2002). degradation, in 1978 emerge the Global Assessment of Soil Degradation (u n e p , 2003). Based on traditional ecology pos- Consequently, there are two main concerns about dryland tulates, the information obtained represented the basis of environments that challenge ideas about their management national policies against desertification and the parameters and protection: the of dryland environments to apply new management systems to dryland environments. and the official fight against desertification. The reformulation of the theoretical approaches regarding dryland environments, originated a new mainstream that 4. The Productivity of Drylands Environments include natural variations and chaotic fluctuations; thus, dryland environments changed form barren wastelands, to Dryland environments cover 41% of the terrestrial surfa- vital ecosystems capable to support human activities (Adger, ce and support more than 36% of the world’s, population et al, 2001; Thomas, 1993; u n e p , 2005). (Ramsey, West and Norton, 2008). The pressure on dryland The -based management in dryland environ- environments productivity is enormous, taking into account ments also challenges the old paradigm that the human the growing population stress and the perceived threat of land activities are the main cause of degradation by overgrazing degradation and desertification. Some definitions of deserti- and overstocking. Traditional practices may provide lessons fication are based on a reduction in productivity; or as United about how to live in these environments without destroying Nations Conference on Desertification u( n c o d ) stated in 1992: them (Bie, 1992; Blaikie, 2006); and represent a lesson for “desertification is a reduction or destruction of the biological the international donors, funding institutions and gover- potential” (u n c c d , 1994). These definitions influence the way nments that have been “… imposing interventions aimed in which dryland degradation was acknowledged. Therefore, at restoring equilibrium onto a non-equilibrium system” dryland environments have been seen as infertile with (Sullivan, 1996:4). low potential to meet the basic requirements of the population that inhabits them (u n e p , 1992). Nonetheless, studies about Conclusions pastoralists in Africa and Latin America reveal that communi- ties also interact within such environments, contributing to the The rise of new theories and ideas regarding ecological general resilience of them (Bie, 1992; Scoones, 1994; Warren, dynamics presents radical changes in the conception of 1995). The production strategies that some communities apply ecosystems and their problems. Dryland environments may to cope with the variable conditions of dryland environments, play an important part of the new efforts for understan- confront the wide spread ideas based on the tragedy of the ding environmental change as well as the role of humans commons in which human activities induce degradation. in protecting and managing natural resources. Therefore, Nowadays there is a growing evidence that shows that the discussion about how dryland environments engage the imminent collapse of the traditional pastoral sector in with the new ecology postulates shows that environmental dryland environments predicted by the old paradigm, can policies and paradigms are intimately interlinked (Warren, be reverted (u n e p , 2005); the effective survival strategies 1995). However, many of the assertions highlighted in the that this evidence reveals (including nomads’ activities, the new ecology are partially determined and thus, other points careful choice of herd species, intimate knowledge of the of view related to the old paradigm remain feasible (Ellis, environment and many others) has now challenge the older Coughenour and Swift, 1993; Swift, 1994; Zimmerer, 1994; points of view (Thomas, 1993; Zimmerer, 1994; Warren, Scoones, 1999). In any case, it is necessary to develop a 1995). The new perspectives about the production of better understanding of how dryland environments work to dryland environments and the beneficial effects of the com- avoid misleading projections about the future of these en- munal good management support that within the dryland vironments, and especially to improve the use of resources context the concept of equilibrium and niche specialization available in these arid systems (Ellis, Coughenour and Swift, is inapplicable. Moreover, “Communities owe their resi- 1993; Swift, 1994; Pimm, 1991; In: Sullivan, 1996). lience to their ability to exploit the very opportunities that Environmental scientists currently recognize the im- system instability offers” (Thomas, 1993:323). portance of natural processes that characterize dryland

CIENCIA ergo sum, Vol. 17-1, marzo-junio 2010. 85 Ci e n c i a s So c i a l e s environments; the relevance of this shift is that ecological However, the shift in ecological paradigms and the chan- thinking is adopting new processes in its effort to un- ges brought by it are subjugated to political interactions. derstand the complex environmental dynamics (Warren, That is the main importance of the change in ecological 1995). Therefore, this new conceptualization of ecological thinking, and the central position taken by this academic dynamics might lead to: a) the development of theoretical effort. Just as Botkin (1990:16) affirms: “The potential for frameworks that demythologize dryland environments as us to make progress with environmental issues is limited ‘extreme’ environments (Sullivan, 1996), and b) the im- by the basic assumptions that we make about nature, the plementation of policies and programmes that bring real unspoken, often unrecognized perspective from which we benefits to these ecosystems and the population that habits view our environment. […] In order to gain a new view, we them, respecting their natural fluctuations and variability must break free from old assumptions and old myths about (Zimmerer, 1994).The narratives provided by empirical nature and ourselves, while building on the scientific and cases in which desertification and dryland environments technical advances of the past”. Hence, nature has provided degradation seem evident challenge not only the very the very means by which it is possible to challenge our own scientific roots of policies and issues of environmental understanding of the world; consequently, the adaptation change, but also highlight the role of social, political and and improvement of the different political approaches in financial institutions on building up a global vision of which not only dryland environments but also the rest of environmental degradation. The evidence provided by ecological endowments are inserted need to be contested, this essay conveys the various reasons by which ecologi- adapted and adopted in political and social spheres in order cal thinking has evolved along the time, creating global to achieve more efficient and equitable management and discourses that influence scientists and donor agencies. conservation processes.

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