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Agricultural policies, land-use and waterbird conservation: the case study of a major Mediterranean wetland, the Camargue

Politiques agricoles, occupation du sol et conservation des oiseaux d’eau : le cas d’une importante zone humide méditerranéenne, la Camargue
Raphaël Mathevet, Christophe Tourenq et François Mesléard

Résumés

Cet article explore le rôle des politiques agricoles sur la dynamique des superficies rizicoles en Camargue, une zone humide méditerranéenne d'importance internationale pour la conservation des oiseaux d’eau. Le riz est la culture la plus répandue dans le delta du Rhône et de nombreuses études ont mis en évidence la forte complémentarité des rizières avec les habitats naturels pour les oiseaux d’eau. Les modifications des interactions agriculture environnement sont donc étudiées à travers deux principaux groupes d'oiseaux, à forte valeur patrimoniale, qui utilisent les rizière comme sites d’alimentation : les hérons et les flamants roses. L'étude de l’histoire régionale, concernant l’évolution de l’occupation du sol et les changements de pratiques agricoles, permet de mettre en évidence les transformations des paysages liées au développement des politiques agricoles nationales et supranationales après la seconde guerre mondiale. L'importance de l'augmentation des superficies en riz pour les hérons coloniaux ainsi que le rôle des modifications des structures paysagères des bassins rizicoles quant aux dégâts aux cultures occasionnés par les flamants roses sont examinés. Ils illustrent comment la faune sauvage et l’agriculture interagissent d’une façon complexe qui doit être comprise afin d’une part de développer des pratiques agricoles adaptées à l’environnement, et d’autre part de favoriser des politiques intégrées de conservation. En conclusion, les auteurs soulignent que comprendre le rôle des politiques agricoles dans l'histoire et la géographie du développement de l’espace rural est un élément fondamental de l’analyse de toute politique de conservation.

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Texte intégral

Introduction

1Although agricultural land accounts for up to 30% of terrestrial lands in the world (Fisher et al., 2000 ) and nearly half of the total land surface of the EU, its nature conservation value has only recently been recognized (Pain and Pienkowski, 1997). The Common Agricultural Policy (CAP), international trade agreements (GATT), and local fiscal policies are mostly responsible for changes in land management over the past 40 years. Since World War II, European and French agricultural policies have aimed to increase food production to reach self-sufficiency (Fumey, 1997). The CAP has promoted a restructuring of farming by increasing the average size of farms and encouraging crop specialization. It is now widely recognized that these agricultural policies have not sufficiently considered the relationships between farming and the environment (Pujol and Dron, 1998).

2Rice farms cover more surface area than any other crop in the world and support waterbird populations of international interest (Fasola and Ruiz, 1997). In Europe, rice farming is restricted to the main wetland regions of the Mediterranean (Italy, Spain, France, Portugal, and Greece). Rice fields as temporary aquatic ecosystems are flooded in spring and summer and dry in winter, which is the opposite pattern of natural temporary aquatic ecosystems in Mediterranean wetlands. They may thus play an important role as substitute foraging and breeding wetlands for birds during the spring-summer period. Birds are an important part of biodiversity, and are often used as biological indicators of environmental health (Peakall and Boyd, 1987). They are the most monitored group in the Mediterranean wetlands. Abundant data on population distribution and dynamics is available (Isenmann, 1993; Crivelli et al., 1996).

3The Camargue lies in the delta of the Rhone river in the Mediterranean coast, south-eastern France (43°30'N, 4°30'E, Fig. 1). This deltaic system covers an area of about 145 000 ha and is characterized by a mosaic of fresh, brackish and saline wetlands interspersed with areas of intensive agriculture and industrialization (Lemaire et al., 1987). It is recognized as a wetland of international importance for its diversity of ecosystems and large numbers of breeding and wintering waterbirds (Heath and Evans, 2000). Covering about 16% of the whole Camargue surface, rice farming constitutes the most widespread crop in the delta, either in rotation with wheat or in monoculture, the alternative crops being limited by soil salinity (Barbier and Mouret, 1992) Earlier studies have highlighted the strong complementarity of ricefields with natural habitats for waterbirds (Pirot et al., 1984; Hafner et al., 1986). Among these, two groups of conservation interest can be distinguished, respectively for their frequent use of ricefields and impact on crop production: herons and flamingos. Colonial tree-nesting herons use ricefields as a foraging habitat during all seasons in the Camargue (Lombardini et al., 2001; Tourenq et al., 2001a). Contrary to herons, flamingos use ricefields as foraging habitat during only a short period, which corresponds to the field flooding phase in May-June and have been responsible for widespread crop damage (Tourenq et al., 2001b).

4In this paper, we examine - through a review of the literature and on the basis of our recent works - how local landscape has changed in response to agricultural policy reforms, and how these land-use and agricultural practice changes have affected the population dynamics of herons and the flamingos’ frequentation of ricefields of the Rhone delta. This case study illustrates how wildlife and farming most often interact in a complex manner, which needs to be understood in order to develop agricultural practices adapted to the environment and to promote integrated environmental policies.

Farming evolution: the direct connection with the world agricultural policies

5Because of malaria epidemics, lack of manpower before the 20th century (Barbier and Mouret, 1992) and unfavourable farming conjuncture rice cultivation remained marginal until 1940. Rice development began during World War II. During the war, food shortage and the interruption of trade with the French Asian colonies made it increasingly difficult to supply the country with rice. Thus, rice farming was attempted, covering some 250 ha in 1942. Faced with technical problems (working with wet soils, lack of specialized material, unqualified man-power...) and low yields, the development of rice cultivation should have been stopped at the end of the conflict. However, during the war, the purchase of land in the Rhone delta secured regional and national industrial capital (Béthemont, 1972; Picon, 1988), and allowed the development of a new hydraulic network and the mechanization of rice farming. Consequently, in 1946 after six years of slow expansion due to lack of machines and technical competence, rice surface area was covering 1,000 ha.

6The Monnet Plan (1946) followed by the Marshall Plan (1948) facilitated the implementation of a new agricultural policy of agricultural modernization. The high price support policy of the French government, the protection of the national market and the creation of cooperative for agricultural machinery in 1948 lead to an increase of rice crop surface area by a factor of five in four years. It reached 20 000 ha in 1951, mainly at the expense of halophytic scrubland (Fig. 2). The loss of economic support in 1954 resulted initially in the maintenance of rice farming because of the impossibility for a large number of rice farmers to reconsider their investment projects (Béthemont, 1972). In 1955/56, the creation of subsidies for pulling up the vineyard contributed further to the development of rice crop, this time at the expense of vine growing. These new incentives resulted in a new growth in rice crop surface area, which culminated in 1960 with 32 500 ha.

7In the Sixties, the decrease of customs tariffs, along with a higher Italian rice productivity and the development of the European Common Market, resulted in a rice price decrease. Associated with these economic changes, the development of new farming difficulties (weed resistance to the first weed killers) and a few years of low yields, induced a significant reduction of rice cultivated surface area in the whole delta. Thus, with the rice crisis at the end of the Sixties, the development of durum wheat (in rotation with rice) and to a lesser extent sunflowers replaced rice monoculture. During the same period (at the beginning of the Seventies) a majority of farmers abandoned sheep farming.

8From 1981 to 1987, a French rice crop revival plan resulted in investments of 1.52 million € in the hydraulic system and subsidies of 76 € ha-1 per year to level fields. Ricefield surface area increased from 5 500 ha in 1982 to 22 000 ha in 1992. With the 1992 CAP reform, the decrease in wheat and oil-production crop support prices, as well as the implementation of a system of quotas for the wheat crop and the growth of direct subsidies to farmers for set-aside, resulted in an increase of rice crop surface area from 1992 to 1994 (Fig. 2). However, the last GATT agreements in 1994 generated a more competitive agricultural market (Chataignier, 1995). Several factors influence the international rice market changes as the low volume of its trade (c.5% of the world production), the limit of self-sufficiency of some large producing countries, the fact that rice is a climatic-sensitive crop, the changes of commercial policy in the support of the rice price in the producing countries, or the fluctuation of the exchange rates and price of energy (Chataignier, 1995).

9In the Camargue as well as in other European rice farming regions, rice crop plays a particularly significant role in the local economy. The international economic evolution weakened strongly specialized areas (Navarro Garcia, 1996). In order to avoid the disappearance of European rice farming and its processing industry, a reform of Rice Common Market Organization was established in 1995, involving (i) the fall of the intervention price by 15% in the EU at a rate of 5% per year since September 1997; (ii) the compensation of this price drop by a direct compensatory subsidy to farmers; (iii) the definition of a common maximum guaranteed surface (MGS) for the whole of the EU and a maximum national guarantee surface. The consequences are (i) the presence on the French market of low-price imported rice, (ii) a decrease of the volumes benefiting of export aids, finally (iii) an increase of intervention stocks. Moreover, with the drop of prices (Fig 3), the small competitiveness of French rice within the EU (lowest yield and highest costs in intermediate goods), and the increase of market share by scented rice products (they represent almost 30% of rice sold in France while the Camargue does not produce this kind of rice waiting for an adapted variety), the agreements of Marrakech strongly worried the professionals of the sector. These global economic changes induced a new significant decline in cultivated surfaces to reach less than 18 000 ha in 1999. Globally, the fall of rice crop income is about 30% in spite of the compensatory subsidies (Fig. 3 & 4). Consequently, rice farmers’ strategy concentrated on wheat crop that benefits of the highest income since 1996 according to a high subsidy (Fig. 4). The wheat farming is particularly well adapted to the Mediterranean climate and its production is well mastered at the technical, phytosanitary and agronomic levels (Mouret, 1988). Nevertheless, its development is limited in the Camargue by the soil salinity, rotation with rice (i.e. temporary-flooding) is needed.

10Moreover, following the Agenda 2000, the wheat quota system disappeared to the benefit of a MGS and a departmental budget for the subsidies. In this context of low price and poor alternative to wheat cultivation, qualitative research on rice crop associated to the present structures of production should make possible to establish satisfactory incomes. The low volumes of rice production from Camargue allow to find a commercial niche, the new option being the use of the reputation of the Camargue and its protected environments in order to develop their production. This orientation lead to the creation of a label certification in 1998 and a Geographical Ascription.

11In spite of conservation constraints with the creation of a National Reserve in 1927 (ca. 13 000 ha) and the creation of a Regional Natural Park in the seventies (ca. 80 000 ha), agricultural development has expanded in the Rhone river delta (Fig. 5). In 1942, natural areas covered about two thirds (67%) of the Camargue compared to less than half in 1976 (39%, fig. 5). The agricultural area primarily increased during the Fifties and Sixties, but this growth continued until the end of the Seventies to be stabilized at the beginning of the Eighties (Fig. 5). Arable lands increased by some 18 000 ha mainly on higher grounds and at the margins of marshes. Various natural habitats were affected by this evolution, starting with those located on the higher or easily drainable lands, such as temporary marshes and halophytic scrublands, as well as grasslands, and to a lesser extent freshwater marshes and ponds (Tamisier, 1990). The whole delta complex underwent the same evolution, irrespective of the considered geographical unit (Tamisier, 1990). Between 1970 and 1991, the natural area, included on the territory of the Regional Natural Park, decreased by 8,7% (ARPE, 1992). Ricefields are the main land-use which has replaced the natural habitats (1 922 ha) during the last two decades (ARPE, 1992). In 1996, the natural area covered 50% of the territory of the Regional Natural Park compared to 18% for the salinas and 25% for agricultural lands.

Importance of ricefields for tree-nesting herons during breeding season

12Among waterbirds, tree-nesting herons Little Egret (Egretta garzetta) and Cattle Egret (Bubulcus ibis) use ricefields for largely foraging particularly during their reproductive season. Within the Camargue, they nest arboreally in mixed-species colonies and have been the focus of long-term studies for over 30 years. The ecology of both species has been extensively studied (Tourenq et al., 2000). Little and Cattle Egrets are both opportunistic and show great variability in habitat use. However, Little Egrets exploit more aquatic habitats (both fresh and salt, permanent or temporary waters) than do Cattle Egrets which frequent open wet or dry pastures and agricultural lands.

13The number of colonies of both species has increased in the Camargue since the 1960s, although colonies are not mutually exclusive since most colonies were of mixed species composition. From 5 in 1976, the number reached about 15 at the end of the Nineties (Fig. 6). Both the total number of Little Egret and Cattle Egrets nests increased during the period considered. An analysis of the relation of the colonial parameters with environmental and agricultural factors, through a generalized linear model framework, showed a strong correlation between the number of Cattle Egret nests and rice cultivated area (Tourenq et al., 2000). The strongest correlation during later years reflects a change in rice management, i.e. use of laser technology, shallower water levels with reduced fluctuation (Barbier and Mouret, 1992). Katzir et al. (1999) showed that Cattle Egrets were not able to catch prey in deep water as do other herons, including Little Egrets. Thus, the intensification of rice cultivation and the changes in agricultural practices (reduction of the water table during cultivation) should have benefited this species. An effect of the increase of ricefield area on the number of Little Egret colonies in the Camargue was demonstrated thus (Tourenq et al., 2001a). Little Egrets are observed in ricefields especially during the chick-rearing period (Lombardini et al., 2001). The strongest hypothesis is that chicks cannot tolerate food from salt water environments; thus ricefields could be alternative fresh-water habitats for foraging during this period.

14The impacts on herons of the practice changes are complex and difficult to appreciate globally. For example, the observed decrease of breeding parameters of Little Egret during the last decades is partially attributed to the inter-specific competition in breeding sites with Cattle Egret (Tourenq et al., 2000). Thus, while benefiting Cattle Egret expansion, rice cultivation changes could have indirectly had a negative influence on some aspects of Little Egret reproduction.

Controversy over conservation: the problem of ricefield frequentation by flamingos

15Some bird species, such as flamingo Phoenicopterus ruber roseus P., are known to cause problems to rice farming in Europe and in the Camargue, in particular (Johnson and Mesléard, 1997). The flamingo forages in ricefields during the seeding phase when fields start to be flooded in May-June. Flamingo is a case in point: (i) it is a strictly protected species, the Camargue being the unique breeding site in France, (ii) it is a flagship species, being one of the symbols of the "wild" Camargue and (iii) it is not dependent on rice for its survival. Therefore, flamingo damage constitutes a potential conflict between nature conservation, tourism, and agricultural production.

16Incursions of flamingos in ricefields were first noticed in the Camargue in 1978. Since then, the presence of flamingos in ricefields has been reported every year (Tourenq et al., 2001b). In the Camargue, around 1 000 ha of ricefields - about 5% of the total rice surface area- need to be partially or totally resown annually. Damage to rice crops was estimated at approximately 215 000 € in 1997 (Johnson and Mesléard, 1997).

17The flamingo is strictly protected in Europe. With about 20 000 breeding pairs at present, the Camargue colony is the most important in the Western Palearctic (Johnson, 1997). Dispersed over some 85 000 ha of wetlands in the Camargue, flamingos usually feed on aquatic invertebrates in brackish or saline lagoons but are also able to forage in freshwater marshes (24). Flamingos visit ricefields mostly between sunset and sunrise, soon after sowing (ca. mid April) and until the rice germination period (in early June). With their large webbed feet, they trample the grain into the earth preventing germination. Seeds may also be uprooted and consumed; flamingos are also known to feed on vegetation, including seeds (Del Hoyo et al., 1992).

18Among the main environmental variables that influenced the presence of flamingos in ricefields, two are directly linked with change in rice farming practices: the surface area of ricefields, and the presence of hedges (Tourenq et al., 2001b). Larger fields may be preferred by flamingos because they allow birds to detect predators at greater distances and the absence of hedges increases all-round visibility, reduces the risk of surprise attacks from predators and facilitates take off (Barnard and Stephens, 1981; Whitehead et al., 1995). Between 1968 and 1992 the mean surface of rice plots was multiplied by four in particular due to the destruction of the hedges network (Durieux, 1998).

19We saw previously how rice cultivation dynamics could have on the one hand indirect incidences on some waterbirds’ populations in the Camargue such as egrets. On the other hand, the example of the Greater Flamingo illustrates how some birds species may cause problems to rice farming benefiting from changes in landscape structure and composition, through the expansion of rice surface areas and changes in rice cultivation practices. Because agricultural policies are the driving forces of land use and management (Winter, 2000), the challenge is how to conciliate farming and nature conservation through government intervention.

Rice farming and Nature Conservation: underlying ecology and rural geography relationships

20Camargue rice farming is currently divided between productivism and sustainable development. Two distinct types of rice farms can be identified from our field survey (Mathevet, 2000). The first category of farm (52%) relies on production subsidies to increase its competitiveness, as well as trying to reduce production costs, by exploiting its technical potential and by decreasing fertilizer use. This orientation could certainly result in a reduction of negative externalities on the environment, although it may also promote the use of banned pesticides, as was recently noticed (Vaudoit, 2001). The second type is a rice farm (48%) oriented towards mixed-farming, tourism and commercial hunting for financial reasons (debt), physical reasons (land availability) or because farmers believe that income sustainability can only come through diversification. Agro-environmental policy measures (AEM) are a significant element of this strategy as they avoid the dependence on one single source of income and increase benefits (tourism, agricultural output) to farmers. The impact of this agricultural management strategy could be positive for landscape and waterbird diversity. However, the last CAP reform could lead some farmers to change from rice crop to other dry cash crops such as wheat, oil-production crops or to develop hunting marshes in natural habitats and in former ricefields as has been observed in the recent past (Mathevet and Tamisier, 2001). This could have as we have seen earlier, an important impact on aquatic avifauna diversity, breeding herons, and incursions of flamingos.

21In this context, the CAP support for the environmental and rural roles of agriculture is insufficient (Desquilbet et al., 1999; Gohin et al., 1998). However, the new French Law of Agricultural Orientation (approved LAO on May 26, 1999) takes into account economic, environmental and social functions of agriculture and its contribution to the regional planning for a sustainable development (Mahé and Ortalo-Magné, 2001). Territorial Contracts of Exploitation (TCE) constitute the contractual instrument of the new LAO. In the long term, TCEs should integrate the majority of agro-environmental schemes resulting from the 1992-CAP. The future implementation of the TCE should become tangible with a re-evaluation of the model, and support for a new landscape management approach.

22Recent studies indicated substantially higher use of natural marshes by waterbirds in the Camargue (Tourenq et al., 2001a). The disparity between uses of these habitats might be reduced if management of ricefields takes into account use by waterbirds. Elphick (2000) recently suggested that, if managed appropriately, ricefields might provide valuable foraging habitats for waterbirds, replacing the function of natural wetlands on which ricefields were cultivated. During the winter, ricefields may be extensively used by waterbirds for foraging on rice grains left over from the harvest, and on aquatic vegetation and/or invertebrates that would otherwise be absent (Beck et al., 1999; Elphick, 2000). In the Camargue, only about 10% of ricefields are managed for game hunting. However, this agro-ecosystem might be less interesting for some species (e.g. Little Egrets) than others (e.g. Cattle Egrets).

23Incursions of flamingos could be prevented by surrounding ricefields with hedgerows. In addition, hedgerows are likely to enhance local biodiversity in agro-ecosystems and offer agronomic advantages as a physical buffer against wind mechanic and thermal stress (Barbier and Mouret, 1992; Baudry, 1988; Sotherton et al., 1998). Nevertheless, most rice farmers do not perceive their positive value, as they make aerial spraying, other wise easier and quicker to realize than grounded operations, more difficult. Restoration of hedges could limit flamingo incursions in the more threatened ricefields. This is one of the prescriptions of agro-environment schemes promoted by the European Community (Ovenden et al., 1998) and the new TCEs.

24As a symbol of the "wild" Camargue for thousands of tourists, the emblematic Flamingo is used in promoting regional products, including rice. Therefore, flamingo damage constitutes a potential conflict between nature conservation, tourism, and agricultural production. In Europe, and in the Camargue in particular, the conflict is likely to intensify with an increasing population of flamingos (less than 10 000 breeding pairs in 1980 and about 25 000 in 1995) and increasing economic pressures on rice farming. The invasion of ricefields by flamingos may appear to be a trivial problem at an international or national scale, but at a regional or local scale, the situation is critical.

25Thus, it is necessary to integrate the dynamics of landscapes in the management of waterbird populations. In the Camargue, the agro-environment schemes concerned primarily natural habitats used for bull grazing. Due to the support price policies of the 1992 CAP, AEM had limited impacts on arable lands. The compensatory subsidies of about 500 € ha-1 for oil-production crops and durum wheat, with suitable reference yields and the maintenance of world levels higher than the forecasts, increased the income of intensive farming. Obviously, this productivist logic did not encourage farmers to support the establishment of protection measures for wetlands. However, the new national agricultural policy opens prospects for a new ecological inflection, which should benefit natural habitats.

26Conservation interests, because of functional interdependencies, rely on management decisions in private land. While management of private marshes for hunting, associated with rice farming, involves positive externalities for ducks and a number of fresh water birds, it has a negative impact on other species, such as saltwater plants species and other species typical of Mediterranean ecosystems (Tamisier and Grillas, 1994). The analysis of agricultural regulations consequences underlined the need for modifying the rules in order to develop a global strategy for the conservation of wetlands. Existing regulations must be adapted, recognizing that economic incentives have a fundamental role to play.

27Agro-environmental schemes involve a new structuring of the territory, at the level of the field (evolution of agricultural practices), of the farm (diversity of production systems) and of the landscape (dynamics between agricultural and rural uses, new landscape mosaic and its impact on birds communities). However, until now ecological and socio-economic evaluations have not taken into account these three levels simultaneously. Thus, there is a need in the future to study the coherence of AEM and TCEs, and their effects on the unit at these three levels. The successful implementation of future agro-environmental measures and TCEs depend on the inciting character of the subsidies but also on farmers’ willingness and ability to change farm management (Beedell and Rehman, 2000).

28The idea of wetland conservation is an unstable point of balance between contrary forces. The main gap is the understanding of the dynamic relations between human activities and the functioning of ecosystems (Pinchemel, 1988; Bertrand, 1992). It is a question of giving more importance to the knowledge of individuals and involved social groups, and to integrate the multidimensional character of individual and collective interests (Jollivet, 1997; Roberts, 2001). However, the demonstration and the study of the causal relations influencing the loss of biodiversity remain difficult (Forester and Machlis, 1996; Cortner, 2000).

29There is scope for a positive integration of environmental issues into CAP and establishing linkages with local environmental heterogeneity and specificity of wetlands. The European Union regional programmes attempt to move towards a rural policy rather than a CAP and it is likely that in the future better emphasis will be placed on the environmental and social dimensions of rural development (Mahé and Ortalo-Magné, 2001; Roberts, 2001).

Conclusion

30Like in other worldwide wetlands, the Camargue agriculture has been transformed in the space of fifty years through several and spectacularly rapid, processes of intensification and crop specialization. It is difficult to underestimate the CAP and GATT impacts on agricultural land and birds throughout the Rhone delta. Rice farming was a determining element in the development of the Camargue, promoting the desalinisation of uncultivated lands and contributing largely to the improvement and development of the hydraulic network. Supranational and national agricultural policies affected significantly rice farming evolution.

31The 1992 and 2000 CAP measures are insufficiently focused on environmental improvement. Consequently, the discussion on the need to reform the CAP remains a hot topic. The relationships between agricultural policies, land-use changes, and heron population patterns remain highly complex, non univocal and specific to wetlands. Our results concerning flamingos’ ricefield damages can already be used to suggest appropriate planting of hedgerows and to avoid woodcutting in high-risk areas. However, in the Camargue, environmental management increasingly relies on the use of environmental management instruments such as incentive-based mechanisms. The latter offer a great opportunity to solve agriculture-related environmental problems, but the relationship between scientists, conservationists, and rural communities has become a critical issue. Our study suggests that understanding more about the role agricultural policies play on land-use and waterbird dynamics is fundamental to any conservation policy analysis. Of particular importance is the conclusion that we can’t understand the ecological processes operating in an agro-ecosystem without knowing as much about the agriculture system history and geography as conservationists do about the biological system. There is an obvious need to link the approaches to integrate system dynamics, scale and cross-scale interactions in both human and natural systems. With a better understanding of the implications of agricultural policy in wetlands, we will be able to begin to address the conservation policy questions concerning how agricultural management might affect the overall waterbird dynamic and how choices based upon ecological and socio-economic heterogeneity and wetland specificity might be made. Rural geography appears to be at the crux of a powerful trans-disciplinary framework that combines the concerns of the conservation biology, the landscape ecology and the political ecology at scales from the micro-level to the macro-level. As sustainable development still raises more questions than it has been solving until now, it is necessary to develop this kind of trans-disciplinary approach on human-environment interactions, that embraces more holistic and integrated fields to rethink the efficiency of agricultural policy towards sustainable development.

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Bibliographie

Barbier J.M., Mouret J.C., 1992, "The rice crop and the Camargue. History and Research". (in French). INRA mensuel 64/65, 39-51.

Barnard C.J., Stephens H., 1981, "Costs and benefits of single and mixed species flocking in fieldfares (Turdus pilaris) and redwings (Turdus iliacus)". Behaviour 84, 91-123.

Baudry J., 1988, "Hedgerows and hedgerow networks as wildlife habitat in agricultural landscape". In: Environmental management in agriculture: European perspectives. Park, J.R. (ed.), Belhaven Press, London, 11-124.

Beck,N., Mesléard F., Mondain-Monval J-Y., 1999, "Impact de la gestion hivernale des rizières de Camargue sur les macro-invertébrés aquatiques et sur la bécassine des marais (Gallinago gallinago)". Gibier Faune Sauvage Vol. 16 (2), 123-141.

Beedell J., Rehman T., 2000, "Using social-psychology models to understand farmers’conservation behaviour" Journal of Rural Studies, 16, 117-127.

Bertrand C., Bertrand G., 1992, "Territorialiser l’environnement un objectif pour la géographie", G.A., 10, 63-74.

Bethemont J., 1972, Le thème de l'eau dans la vallée du Rhône : Essai sur la génèse d'une espace hydraulique, State PhD dissertation, University of St Etienne.

Chataignier J., 1995, Perspectives de la consommation du riz dans les pays européens et méditerranéens. Cahiers Options Méditerranéennes, Vol. 15, 1, 87-93.

Cortner H.J., 2000, "Making science relevant to environmental policy", Environmental Science and Policy, 3, 21-30.

Crivelli A.J., Hafner H., Fasola M., Erwin, R.M., McCrimmon D.A. Jr. (eds)., 1996, "Ecology, conservation, and management of colonial waterbirds in the Mediterranean" region, Colonial Waterbirds, 19 (special publication 1).

Del Hoyo J., Elliot A., Sargatal J. (eds), 1992, Handbook of the Birds of the World, Vol. 1, Ostrich to Ducks. Lynx Edicions, Barcelona.

Desquilbet M., Gohin A., Guyomard H., 1999, "La réforme Agenda 2000 de la politique agricole commune : une perspective internationale", Economie et Statistique, 329-330, septembre-octobre 1999, 18-20.

Durieux L., 1998. Etude de la dynamique paysagère du milieu rizicole de l'île de Camargue. McS, University Aix-Marseille, France.

Elphick C. S., 2000, Functional equivalency between ricefields and semi-natural wetland habitats. Conservation Biology, 14, 181-191.

Fasola M., Ruiz X., 1997, "Rice farming and waterbirds: integrated management in an artificial landscape", In: Farming and Birds in Europe. Pain D., Pienckowski M.W., (eds), Academic Press, London, 210-235.

Fisher G., Van Velthuizen H., Nachtergaele F., Meadow S., 2000, Global agro-ecological zones. FAO-IIAS, Rome.

Forester D.J., Machlis G.E., 1996, Modeling Human Factors That Affect the Loss of Biodiversity. Conservation Biology, Vol 10, 4, 1253-1263.

Fumey G., 1997, L’agriculture dans la nouvelle économie mondiale, PUF, Paris.

Gohin A., Gorin O., Guyomard H., Le Mouël C., 1998, Les propositions Agenda 2000 de réforme de la politique agricole commune et le projet de loi d'orientation agricole en France : quel modèle agricole pour demain ? INRA Mensuel n° 99, octobre-novembre 1998, 32-38.

Hafner H., Fasola M., 1992, The relationship between feeding habitat and colonial nesting Ardeidae. In: Managing Mediterranean wetlands and their birds Proceedings of the Symposium of Grado, Italy. Finlayson C.M., Hollis G.E., Davis T.J. (eds.). IWRB Special Publication 20, Slimbridge, U.K., 194-201

Hafner H., Dugan P.J., Boy V. 1986, "Use of artificial and natural wetlands as feeding sites by Little Egrets (Egretta garzetta L.) in the Camargue, southern France" Colonial Waterbirds 9, 149-154.

Heath M.F., Evans M.I., 2000, (eds.) Important Bird Areas In Europe: Priority Sites for Conservation. Vol. 2: Southern Europe. BirdLife International Conservation Series N°8. Cambridge, UK.

Isenmann P., 1993, Birds of the Camargue. SEO - Muséum National d’Histoire Naturelle, Paris.

Johnson A.R., 1997, Long-term studies and conservation of Greater Flamingos in the Camargue and Mediterranean. Colonial Waterbirds, 20, 306-315.

Johnson A.R., Mesléard F., 1997. Les flamants et la riziculture. In : (Clergeau, P., ed.), Oiseaux à risques en ville et à la campagne, INRA Editions, Paris, 53-60.

Jollivet M., 1997, Vers un rural post-industriel. Paris, L’Harmattan.

Katzir G., Strod T., Schechtman E., Harelis S.and Arad Z., 1999, "Cattle Egrets are less able to cope with light refraction than are other herons", Animal Behaviour 57, 687-694.

Kushlam J.A., Hafner H., 2000. (eds). Heron Conservation. London, Academic Press.

Lemaire S., Tamisier A., Ganier F., 1987, Surface, distribution et diversité des principaux milieux de Camargue, leur évolution de 1943 à 1984. Revue Ecologie, Terre et Vie, 4, 47-56.

Lombardini K., Bennetts R. E., Tourenq C., 2001, "Does foraging success explain habitat use by Cattle Egrets and Little Egrets in Camargue, South France?" Condor, 103, 38-44.

Mahé L.P., Ortalo-Magné F., 2001, Politique agricole, un modèle européen. Paris, Presses de Sciences Politiques.

Mathevet R., 2000, Usages des zones humides camarguaises: enjeux et dynamique des interactions Environnement/Usagers/Territoire. PhD dissertation, Lyon 3 University.

Mathevet R., Tamisier A., 2001, Creation of a nature reserve, its effects on hunting management and waterfowl distribution in the Camargue (southern France). Biodiversity and Conservation. (in press).

Mouret J.C., 1988, Etude de l’agrosystème rizicole en Camargue dans ses relations avec le milieu et le système cultural : aspects particuliers de la fertilité. PhD dissertation, Languedoc University, LECSA, INRA.

Navarro Garcia L., 1996, "Economias dependientes del arroz producido en las marismas del Guadalquivir", Cahiers Options Méditerranéennes, Vol. 15, 2, 133-142.

Ovenden, G.N., Swarh, G.M., and Smallshire, D. 1998. "Agri-environment schemes and their contribution in the conservation of biodiversity in England", Journal of Applied Ecology 35, 955-960.

Pain D., Pienkowski M.W. (eds), 1997, Farming and Birds in Europe. London, Academic Press.

Peakall D.B., Boyd, H., 1987, Birds as bio-indicators of environmental conditions. In: The value of birds. Diamond, A.W., Filion, F.L., (eds.). International Council for Bird Preservation, Technical Publication 6, Cambridge, 113-118.

Picon B., 1988, L’espace et le temps en Camargue. Arles , Ed. Actes Sud.

Pinchemel P., Pinchemel G., 1988, La face de la terre. Paris, Armand Colin.

Pirot J.Y., Chessel D., Tamisier A. 1984. "Exploitation alimentaire des zones humides de Camargue par cinq espèces de canards de surface en hivernage et en transit. Modélisation spatio-temporelle". Revue d’ Ecologie. (Terre et Vie) 39, 167-192.

Pujol J.L., Dron D., 1998. Agriculture, monde rural et environnement: qualité oblige. Rapport à la Ministre de l’Aménagement du Territoire et de l’Environnement. Paris, La documentation Française, Collection des rapports officiels.

Roberts P., 2001, "Incorporating the environment into structural funds regional programmes: evolution, current developments and future prospects", European Environment, Vol. 11, 2, 64-74.

Sotherton N. W., Granval P., Havet P., Aebischer N.J., 1998, Special workshop: field margin strips - Proceedings of the 23th Congress of the International Union of Game Biologists, Lyon, France, September 1997. Gibier Faune Sauvage - Game Wildlife, 15 (Special Publication 1), 11-173.

Tamisier A., Grillas P., 1994, "A review of habitat changes in the Camargue : an assessment of the effect of the loss of biological diversity on the wintering waterfowl community". Biological Conservation 70, 39-47.

Tamisier A., 1990, Camargue : Milieux et Paysages - Evolution de 1942 à 1984. Montpellier, arcane-sretie-cnrs-ad’hoc informatique.

Tourenq C., Aulagnier S., Durieux L., Lek S., Mesléard F., Johnson A.R., Martin J.-L., 2001, "Identifying ricefields at risk from damage by the greater flamingo" Journal of Applied Ecology 38, 170-179.

Tourenq C., Bennetts R. E., Sadoul N., Mesleard F., Kayser Y., Hafner H., 2000, "Long-term Population and Colony Patterns of Four Species of Tree-nesting Herons in the Camargue, South France", Waterbirds, 23, 236-245.

Tourenq C., Bennetts R.E., Kowalski H., Vialet E., Lucchesi J.-L., Isenmann P., 2001, "Are ricefields a good alternative to natural marshes for waterbirds communities in the Camargue, southern France?" Biological Conservation, 100, 335-343.

Vaudoit H., 2001, "Des riziculteurs pollueurs épinglés: ces producteurs camarguais ont utilisé des pesticides interdits", Journal Libération du jeudi 8 février 2001.

Whitehead S.C., Wright J., Cotton P.A., 1995, "Winter field use by the European Starling Sturnus vulgaris: habitat preferences and the availability of prey." Journal of Avian Biology 26, 193-202.

Winter M., 2000, "Strong policy or weak policy? The environmental impact of the 1992 reforms to the CAP arable regime in Great Britain", Journal of Rural Studies, Vol. 16, 1, 47-60.

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Raphaël Mathevet, Christophe Tourenq et François Mesléard, « Agricultural policies, land-use and waterbird conservation: the case study of a major Mediterranean wetland, the Camargue », Cybergeo : European Journal of Geography [En ligne], Environnement, Nature, Paysage, document 221, mis en ligne le 24 février 2002, consulté le 21 novembre 2019. URL : http://journals.openedition.org/cybergeo/3755 ; DOI : 10.4000/cybergeo.3755

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Raphaël Mathevet

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mathevet@tour-du-valat.com Station Biologique de la Tour du Valat, Le Sambuc, F-13200 Arles, France

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Christophe Tourenq

chercheur en ornithologie, Station Biologique de la Tour du Valat, Le Sambuc, F-13200 Arles, France

François Mesléard

chercheur en écologie végétale, Station Biologique de la Tour du Valat, Le Sambuc, F-13200 Arles, France

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