For some observers, long-term fallows are more than welcome. They are seen as a sign ofand vehicle for the return of wildlife and wildflowers to the countryside.
7 Abandoned Lands and Land Use Conflicts in Southern France M. ETIENNE, J. ARONSON and E. LE FLoc'H
7.1 Introduction Across southern France, and in adjacent countries, large areas of formerly populous, productive agricultural lands are being abandoned (Gonzalez Bernaldez 1989; Baudry & Bunce 1991;Farina 1993). In many of these areas, native mediterranean woodlands are making a dramatic comeback, albeit in modified forms due to faunistic, floristic and ecological changes induced during the multi-millennial history of human occupation, exploitation and resource management. At present, some 1% of the overall area of Languedoc-Roussillon, for example, is "reverting" to woodland each year. For some observers, long-term fallows are more than welcome. They are seen as a sign of and vehicle for the return of wildlife and wildflowers to the countryside. For others, however, it signals a failure to maintain a rural way of life rich in knowhow, traditions and local lore. Comprehensive data are lacking on whether biodiversity is going up or down as a result , but at the landscape level it is certain that a former mosaic or patchwork quality is being lost. No doubt this will favor the return or spread of some (Mediterranean) organisms while limiting others. Finally, the long-term economic potential of the numerous resou rces previously exploited is being neglected and degraded, if not definitively lost. Similarly, options for modified land use in the face of unpredictable changes in regional, national or global realities are being lost . In this paper, we propose some terminology and a general approach for planning, evaluating and, hopefully, reorienting rural and regional planning in southern France. For this task, we combine ecological, historical and socio-economic considerations, and we argue that all three are necessary. Specifically, we argue that it is desirable, not to say necessary, to "pilot" Mediterranean ecosystems and landscapes, even in the absence of a short-term profit motive. Like many ecologists, we reject current market economics to the extent that monetary values are not customarily attached Ecological Studies, Vol. 136 Rund el et al. (eds.) Land scape Degrad ation and Biodiversity in Mediterr an ean- Type Ecosystems © Springer-Verl ag Berlin Heid elberg 1998
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to nonmarketed, but tangible and important, functions of ecosystems, i.e. «free nature services" (Westman 1977). After defining our terms and providing a brief historical overview of ecosystem trajectories in the study area, over the past two millennia, we present four case studies where conflicting interest groups contribute to the difficulty of integrated land use planning. Each current human activity is analysed in terms of its ecological impact, the political force of the social group involved, and its relative spatial and temporal importance. Various scenarios of revised land use are then presented and compared for one study area, prior to offering some recommendations for those among decision-makers seeking a truly integrated land use plan. We conclude with a general discussion of the future of mediterranean ecosystems and landscapes in the wider theatre of southern France.
7.2 General Processes Affecting Landscape Transformation Chorematic models (Brunet 1986) of changes in rural landscape structure are given for four types of land use dynamics typical of current trends in the French Mediterranean region (Fig. 7.1). Two processes correspond to fallow land development: (1) abandonment of marginal crop fields or of agricultural activities on high labour-consuming soils (e.g. terraces in Corsica, the Cevennes or the Pyrenees; wheat fields in the Prealpes): (2) end of forest management, especially in the holm oak coppices, but also in the chestnut groves of Corsica and the Cevennes, and in the maritime pine forests of the Maures and Esterel mountains. Two processes deal with use diversification: (1) the substitution of traditional forest management by new activities linked with the demand for recreation in the coastal forests of Provence and the eastern Pyrenees; (2) the recuperation of rangelands for developing new agricultural or industrial activities, especially in the plains of La Crau or eastern Corsica. These processes are illustrated below by four case studies wherein novel land planning objectives are proposed, taking into account ecological criteria and the functional role of biodiversity.
7.3 Three Responses to Ecosystem Degradation or Abandonment We have previously presented (Aronson et al. 1993a) a general model describing the degradation of ecosystems in arid and semi-arid lands,
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1990
1790
o H
ivc
Legend
•
•
Relative importance of agglomerations
Forest under exploitation
we
FJ
Forest unexploited
ivc Irrigated vegetable cropping
M
Maquis
V
Vineyards
G
Garrigue
0
Orchards
W
Woodland
H
Hay fields
P
Pasture
f
Fallow fields
I
Industry
F
Wheat cropping
Fig.7.1. Four typical land use dynamics in the French Mediterranean region during the last century
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under the effects of prolonged, anarchic exploitation of resources and, more recently, rapidly growing human and, often, livestock density. In that model, we also distinguished between the three principal responses to degradation: restoration, rehabilitation and reallocation. In the special context of the Mediterranean Basin, we here propose that abandonment of long-standing agro-ecosystems is tatamount to "degradation". In so doing, we also broaden our enquiry to consider landscapes as an equally important hierarchical level as ecosystems. Now, we shall define our terms. Restoration seeks a complete or near-complete return of a site to a preexisting state, by reassembling, insofar as possible, a species inventory corresponding to the fauna and flora presumed to have constituted the preexisting ecosystem. Rehabilitation seeks to repair damaged or blocked ecosystem functions, with the primary goal of raising ecosystem productivity for the benefit of local people . Emphasis is placed on sustainability of all production systems and on functional and structural attributes related to flows and fluxes, nutrient cycles, food webs. Reallocation is a general term describing what happens when part of a landscape, in any state, is assigned a new use that does not necessarily bear any relationship with the structure or functioning of the pre -existing ecosystem. It usually assumes a permanent managerial role for people and normally requires ongoing subsidies in the form of energy, water, and fertilizers. It is often irreversible, at least in the time scales of a human generation or lifetime.
7.4 Historical Overview The specific dynamics of anyone system will be contingent on its history (Pickett and Parker 1994). Moreover, in any region oflong human occupation, certain periods of the near or distant past can have special importance in determining the current appearance of landscapes and, indeed, the trajectory and content of their constituent ecosystems. This is certainly true of mediterranean France, where a few crucial human activities have lastingly marked the landscape over the past two millenia. Four case studies will illustrate this point.
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7.5 Case Studies In analysing the case studies that follow, we employ the terms and concepts laid out above, along with additional multiple criteria of evaluation. Each case study will be briefly introduced with a description of the bio-physical environment, an historical review of the exploitations and "development" undertaken, and of the current conflicts among those involved locally. Current human activities will then be analysed by means of a grid designed to allow a comparison of the ecological impact and spatio-temporal and sociological dimensions of each. The principal ecological criteria employed are as follows: 1) longevity (long) of the human activity; 2) degree of artificialisation (artif) involved, a useful indicator of the transformations imposed upon the indigenous ecosystem (and landscapes) by successive reallocations; 3) the degree of modification of basic structures (mod) at the ecosystem or landscape levels; and 4) reversability (rev), or relative feasability of returning to a preexisting ecosystem trajectory. Each activity is also situated in time, space and social context with the aid of the following three criteria: 1) spatial occupation (space), as the percentage of the landscape concerned by the activity; 2) temporal occupation (time), as the duration of the activity on the scale of one calendar year; 3) social force (soc), which indicates the size and political clout of the social group concerned. 7.5.1 The Terraces of Interior Corsica Bearing testimony to the colossal efforts of a rural society that until recently had to provide all its own food in a steep, mountainous region, the terraces of central Corsica are visable today only after wildfires remove the invading, all-covering maquis. Prato and Piedigriggio provide good examples of picturesque, perched villages floating in a sea of Cistus (rockrose), with here and there a few stands of Quercus ilex (holm oak) on the more inaccessible slopes. A few rare flocks of sheep or cows make a meagre living from these pasture lands continually ravaged by fire. By contrast, 200 years ago a totally different image prevailed, as revealed by the Land Use Map ("Plan terrier") drawn up by Napoleon's geographers between 1770 and 1795 (Albitreccia 1942). At that time, 70% of the land surface in these two townships was devoted to cereal production, while the rest was either reserved for grazing lands or unused maquis (Etienne 1977). In the ensuing century, nearly all agricultural activities disappeared, except for a bit of viticulture on the flattest, most fertile lands .
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Animal husbandry influenced the landscape only by means of the periodic fires set by the shepherds to renew shoot growth in the low shrub and herbaceous strata. Table 7.1 shows the principal activities which still remain, hunting and extensive sheep rearing being the two major land uses and shrubland maquis the major landscape feature. The only potential conflict is related to the shepherd pratice of setting fire to open the maquis vegetation. 7.5.2 The Township of Puechabon The township of Puechabon, 30kmNW of Montpellier, occupies 2270ha, mostly in holm oak garrigues, and a grand total of274 residents. For at least 5000 years, fire has been an important land management "tool" in this region. By the end of the 10th century, however, important settlements began to arise , under the aegis of the abbeys of Aniane and St. Guilhem-leDesert, both of which were created around the beginning of the 9th century (Bougette 1950). As a result, clearing and planting, as well as forestry activities, accelerated greatly during this period. Moreover, throughout the late Middle Ages, glassworks and charcoal manufactures consumed huge quantities of wood over vast areas (Saint-Quirin 1904). By the middle of the 17th century, woodcutting had become so important that governmental ordinances requiring reforestation were established in 1669 by Colbert, minister of Louis XIV. In the 1790s, there were some 650 inhabitants at Puechabon (Lalanne 1989). From that time, and up to the first third of the 20th century, there was a highly varied land use occupation including cereals, vineyards, olive Table 7.1. Evaluation' of human activities in interior Corsica according to multiple criteria date"
Activity
long
artif
ca.1600 ca.1600 ca.1800 1970
Hunting Wood-cutting Livestock rearing Viticulture
+ + +
0
0
+
' +,
mod
0
+
rev
space
+ +
+ +
time
soc
+ + +
0 0
0 or - indicates an intensity gradient for the ecological criteria (longevity, artificialization, structure modification, reversability) as well as the ratio of space and time concerned or the social pressure of human activities, i.e. for time + = 12 months, 0 = 6 months and - = 1-2 months per year. "Dates correspond to the first appe arance of each activ ity in the region but the evaluation is based on the current situation.
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Table 7.2. Evaluation" of human activities in the township of Puechabon according to multiple criteria Date"
Activity
long
artif
SOOOOB.P. SOOOB.P.
Hunting Sheep rearing Cerealiculture Woodcutting Viticulture Ecotourism
+ +
0
ca. ca. ca. ca.
1100 1100 1800 1980
+
+ + + +
0
0
+ + +
mod
rev
space
time
soc
+ + +
0
0
0
+ +
+
+ +
"see comments at the bottom of Table 7.1.
groves, grazing lands and, above all, intense forestry activities. Several light industries, including distilleries, tanneries, cotton and silk manufacturers, co-existed with and depended on agriculture, animal husbandry and forest activities in a more or less integrated fashion. Table 7.2 shows the principal activities which have transformed the township, with approximate dates of their initiation. Certain activities, e.g. animal husbandry, have been completely abandoned. Others, such as hunting and woodcutting, continue, but in an entirely new socio-economic context. Hunting for small game is a very popular weekend activity in winter, while collective hunts for wild boars are organized to reduce the number of these unruly predators on vineyards. The woodcutting responds to an increasing demand for chimney firewood in the bedroom communities of Montpellier. Fully one third of the township's revenues derive from the annual sale of woodlots. 7.5.3 The La Crau Plain Near the Camargue, the Plain of La Crau is a site of great biological and ecological interest. A former delta of the Durance River, this is the last surviving large example in France of a steppe formation (Devaux et al. 1983) and associated avifauna (BlondeI1970). This steppe, locally known as "coussoul", is the result of a dry, windy climate and low relief of rounded silicaceous rocks overlying an alluvial water table lying at a depth between 2 and Sm. A zone of intensive sheep rearing from very ancient times (Darluc 1783), the La Crau plain has been host to a range of cereal and animal feed cropping systems since the construction of the Craponne canal in the late 16th century. The installation of a dense network of irrigation canals and the concomitant influx of silt have led to a system of high quality feedproduction with itinerant animal husbandry based on seasonally variable
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forage resources. This combination was furt her enhanced by the possibility of early-season feed production and the exceptional phytosanitary conditions. Starting in the 1950s,direct pumping from the water table permitted the development of early-season melon production, later replaced by fruit orchards. Huge amounts of capital in lan d clearing and levelling are now being invested in efforts to expand fruit production to all areas with shallow water tables. However, wildlife conservation and ecotourism have started to develop. In particular, Tetrax tetrax, the "canepetiere", a protected bird species, provides a rallying point for environmentalists. The history of land use and resource exploitation in La Crau is not limited to agriculture. This large, flat and largely unoccupied space near the sea attracts the attention of industrial and military concerns, including the iron and steel industr y of Fos-sur-Mer and the air base at Istres. Finally, the innumerable round stones, lying in places in layers several dozen meters thick, have kept a number of quarry companies busy since the end of the second World War. This rap id overview and the qualitative analysis of the different activities presen ted in Table 7.3 indicate a rat her sharp rupture around 1945- 1950, between an earlier phase of diverse agricultural activities leading to a diversified landscape organised in bands or zones and a second phase of proliferation and intensification of activities. This latter phase has brought about a near-total restructuring of the plain, which now resembles a sort of archipelago (Fig. 7.2). Severe fragmentation of a formerly homogenous region is taking place, with little or no consideration being given to the interactions among the different "islands" of the archipelago. Based on the data presented in Table 7.3 and Fig. 7.2, three more or less realistic scenarios can be constructed, as shown in Fig. 7.3. These indicate the varying trends of land use occupation that could evolve if restoration, rehabilitation, or continued reallocation were most favored in the coming years. Broadscale restoration of the original steppic vegetation and ecosysTable 7.3. Evaluation' of human activities in the Crau plain according to multiple criteria Date '
Activity
long
artif
mod
ca. 1200 ca. 1800 1950 1950 1970 1980 1990
Sheep rearing Hay making Melons Quarries Steel industry Ecotourism Orchards
+ +
+
0
+
space
time
+
0
0
+ + + +
+
0
+
rev
0
+ +
+ +
0
0
+
+ +
' see comments at the bottom of Table 7.1.
0
+
soc
+ + + + 0
.... .... ... . : ........: ... .. ...... .. '
1850
1700
1990
1950
Fig. 7.2. Schema of evolving land use occupation in the plain of La Crau in the 20th century
a
Foc us on
restoration
b
Focu s on
rehabilitat ion
~ . ~
Coussoul
Hay
fields
Melon
fields
Quarries
~ Orchard s
~
c
foc us on
reallocation
M ilitaryindustrial co mp lex
Fig.7.3a-c. Three scenarios for La Crau based on the notions of restoration, rehabilitation and reallocation
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M. Etienne et al.
tern (Fig. 7.3a) is perhaps not a serious possibility today, given the heavy socio-economic pressures in La Crau. Nevertheless, it is presented here for purposes of contrast and in view of the fact that social priorities might conceivably change in the coming decades. Representing an extreme conservationist position, this scenario would logically call for the elimination of many existing activities considered incompatible with the goals of restoration. In contrast, a rehabilitation program (Fig. 7.3b) would seek a compromise between conservation and development; certain areas of coussoul would be reserved for wildlife, particularly migratory birds. Industrial or military activities would be restricted to areas already so degraded as to appear to have crossed one or more thresholds of irreversibility and, therefore, to have become more or less incompatible with agriculture or nature conservation. Agricultural activities would be encouraged, but would be reorganised, and relegislated. New extractive activities would be discouraged or prohibited altogether. Finally, a reallocation scenario (Fig. 7.3c) would encourage diversification of agricultural production and all other short-term economic activities. Ideally, however, a search for complementarity and peaceful cohabitation among different social groups could be built into regional land use planning and legislation.
7.5.4 Coastal Forest Remnants in Provence (the Colle du Rouet) The coastal forests of the Maures and Esteral massifs provide another case of a rural space with diverse historical and contemporary uses . We take the forest remnant of the Colle du Rouet as an example. The ecosystem of reference is a typical pine-oak forest of Provence. In prehistoric times, such forests occupied virtually all the coastal hills and plains of Provence-Cote d' Azur. This forest remnant (1600ha) occupies most of the Argens River Plain, about 20kmNW of Frejus, on skeletic soils derived from Permian sandstone. There occur several species considered rare or endangered in the French Mediterranean region : quillwort (Isoetes), several orchids and Herman's turtle (Testudo hermanni). From royal hunting dominions, to ecclesiastic possessions in the High Middle Ages, the Colle du Rouet became public land following the French Revolution . From the late 18th century, these woods came under the pressure of woodcutters and cork-takers. Hunting and the occasional installation of beehives were also practised (Table 7.4). During the 19th century however vineyards came to occupy most of the area except 1600 hectares remaining for the time being in the public domain.
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Table 7.4. Evaluation' of human activities in coastal forests according to multiple criteria Date '
Activity
long
ca. 1600 1800 1800 1800 1950 1970 1980 1980 1990
Hunting Woodcutting Bee-keeping Plant collecting Walking Shrub mowing Plant harvesting Sheep rearing Hiking
+ + + + + 0 0
artif
mod
0
rev
space
+ + + + +
+ 0
time
soc
+
+ +
0 0
0
0
0 0
- /0
+
0
0
+
0
0
+ + +
0
' see comments at the bottom of Table 7.1.
In the 1960s, immense stands of maritime pine, Pinus pinaster, were decimated by the cochineal Matsuccocus feytaudi. At the same time, the international market for natural cork experienced a price collapse. As a result, forestry activities declined sharply. Independently, the Cote d' Azur became rapidly overdeveloped creating the demand for green belts near the beaches; where tourists could engage in mushroom or dried flowers harvesting, and hiking. These new forest "users" and the growing problem of human-caused summer fires, during the 1970s and 1980s, led forest managers to set up a network of firebreaks that now occupies some 20% of the surface area of the forest (Etienne et al. 1989). Initially, these firebreaks were created and maintained by foresters with the aid of heavy machinery. Since 1981, the maintenance task has been partially conferred to a shepherd, the Forest Service imposing some management rules but also providing subsidies according to the area grazed by the flock. Additional operations like oversowings or perennial fodder crops have been simultaneously developed to promote an emerging sylvo-pastoral system. The evolution of coastal forests is exactly the reverse of the far more extensive areas of holm oak-dominated garrigues. Here, the top public priority has become the prevention of forest fires, but it is still possible to propose contrasting scenarios.
7.6 Discussion In the simulated example, the restoration and rehabilitation scenarios proposed permit maintenance of a traditional Mediterranean "moving
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mosaic" landscape (Blondel and Aronson 1995), wherein mosaic units correspond to, and are affected primarily by, only one or two principal economic activities. In two case studies, increasing redistribution of land for disparate economic and recreational uses underlies the need for achieving widely-based social consensus on fundamental issues relating to ecosystem "health" and landscape integrity. In practice, the problem will be to reconcile nature conservation with sustainable development and to assure ecological and socio-economic compatibility of unrelated activities in a shared "commons" (sensu Hardin 1968). It also raises crucial issues related to the social and economic means available, and the scientific and managerial tools needed to achieve skillful piloting of ecosystems. More challenging still will be the reintegration (or even redesigning) of landscapes to meet new needs and realities in an increasingly crowded region. In the two other case studies, by contrast, land abandonment and the narrowing of economic activities over a relatively short period have favored relatively homogeneous areas and lead to a dangerous situation of high fire risk, among other things. It is, however, possible to imagine different strategies for reintegrating these Mediterranean landscapes by a co-ordinated series of restoration, rehabilitation and reallocation operations. Different portions of each landscape would be preferentially reserved for one of these, based on preliminary studies in situ, and an analysis of the probable modes and pathways of connectivity between and among ecosystems. As mentioned above, we envision such a reintegration as being a collective enterprise. In general terms, restoration should be attempted for those sites of particular importance for conservation of threatened species, e.g., marshes and other wetlands, as well as for maintaining high beta and gamma diversity. Moreover, some ecotones, movement corridors, and other natural areas should be candidates for restoration, as might sites of particular cultural significance or historical importance, such as springs, pre-historic villages and burial sites, medieval abbeys, etc. Secondly, rehabilitation should be given priority for those degraded areas where agricultural, pastoral or sylvo-pastoral productivity can conceivably be profitable, in selected portions of the area, long-, mid-, or shortterm. Additionally, in some areas of no interest to farmers or animal breeders, rehabilitation could be favored as a means to assuring long-term productivity, and flexibility in the face of an unpredictable future. This assumes that maintaining high biodiversity and "healthy", resilient ecosystems is the best guarantee of long-term productivity. We do not pretend to have a recipe for managing all the varied land, water and bio-resources in the area. Our goal is merely to suggest the need for applying multiple criteria (ecological, economical and sociological) in
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rural planning, and to favor ecological ones when planning activities of widescale, long -lasting consequences for ecosystems and landscapes. We maintain that it is essential to collectively direct the trajectories of ecosystems and landscapes so as to maintain high biodiversity, ecosystem resilience and flexibility, and high quality of life. When using the terms "restoration of ecosystems" or "reintegration oflandscapes", moreover, we do not seek a blind, or emotional adherence to past patterns and uses. This would be foolhardy and doomed in advance, except in the dubious context of "living museums". We seek an approach to land use planning and resource development that is more audacious and effective than anything currently practised under existing French law and custom. We see it also as being more conservative of biodiversity, or ecodiversity, i.e. biological, ecological and cultural diversity (Naveh , Chap. 2 this vol.), while at the same time profoundly subversive, to the extent that current economic "rules" are not respected. In so saying, we follow Garret Hardin (1985) in calling ecology itself a "conservative, subversive science" . Many, if not most, of the ecological problems of modern society simply cannot be solved by technical solutions alone. Acknowledgements. We thank the draw ing studio of the CEFE-CNRS of Montpellier for the figures .
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