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Measures to Conserve Biodiversity in Sustainable Forestry:
The Río Cóndor Project

Mary T. Kalin Arroyo
Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile

Introduction.

Forests occupy about 5,000 million hectares (Constanza and others 1997), the equivalent of one-third of all terrestrial ecosystems, and constitute a substantial fraction of Earth's vegetation. Some 60% of forest is at temperate (in a broad sense) latitudes (Constanza and others 1997), and that is where most forests are managed for timber and other commodities. Temperate forest is unequally distributed among the two hemispheres. Less than 10% occurs in the Southern Hemisphere (Arroyo and others 1996), this being concentrated mainly in the widely disparate areas of southern Chile and neighboring Argentina, New Zealand, and Tasmania.

Forests provide a wide range of ecosystem services and goods. The goods are wood, edible plants and fungi, medicinal plants, microorganisms with potential biological activity, ecotourism, and recreation. The services include maintenance of hydrological cycles and air and water quality, regulation of regional climate, nutrient cycling, soil conservation, carbon storage, provision of habitats for wildlife, and contributions to regional and local aesthetics. In a provocative paper attempting to calculate the monetary replacement value of the ecological services provided by Earth's ecosystems, forests were estimated to contribute 38% of total terrestrial ecosystem worth, the equivalent of $4.7 trillion per year, or $969/ha per year (Constanza and others 1997).

Forests, both temperate and tropical, house large amounts of biodiversity (figure 1). Apart from the more visible elements—such as birds, reptiles, mammals,

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Figure 1
Biodiversity on the Río Cóndor property as now known, expressed in terms of species and
generic richness for the main groups of organisms. Data on insects (mostly litter- and
soil-dwelling) are for coastal forest only. Other figures based on sampling of entire property
and nonforested and forested habitats. Amphibians do not occur in Tierra del Fuego.
Data on fungi unavailable. Original data from Arroyo and others 1996.

and vascular plants—forests exhibit strong representation of the less conspicuous and often poorly known groups of organisms, such as bacteria, fungi, lichens, bryophytes, mollusks, and terrestrial arthropods. Some 70,000 species of fungi, well represented in forests, are recognized worldwide, but extrapolations suggest that there could be as many as 1,500,000 species (Hawksworth 1991). Some 2,000 species of ectomycorrhizal fungi are associated with Douglas fir alone in the Pacific Northwest (Marcot 1997). A high proportion of the estimated 16,000 bryophytes (Heywood and Watson 1995) also belong to forests. Some 1,200 species of beetles were collected on a single tree in Panama (Erwin 1982), and 492 species of insects, mostly from litter and surface soil layers, were found in coastal forest in Tierra del Fuego (Arroyo and others 1996). An estimated 7,000 species of arthropods (in comparison with 26 species of mammals, including bats) are found in late successional forests in the Pacific Northwest, containing a handful of trees (Marcot 1997). Tropical forests are evidently richer in tree species than their temperate counterparts, as indicated by a record of 473 tree species in a single hectare in Ecuador (Heywood and Watson 1995). However, the 1,200 tree species in temperate forests worldwide are not to be ignored (Heywood and Watson 1995). Temperate rain-forest trees, moreover, can show high diversity in

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vascular-plant epiphytes, as seen in the finding of 28 species on a single tree in New Zealand (Heywood and Watson 1995).

This essay addresses ecological sustainability and biodiversity conservation in a managed forest landscape. It refers to concrete actions for conserving biodiversity in a private sustainable forestry initiative, the Río Cóndor project in Tierra del Fuego, southern Chile. Less than 10% of the earth's terrestrial surface is protected, and conservation value in the past was more often influenced by scenic beauty and wilderness value than by biodiversity, such that existing protected areas are now often inadequately distributed for the protection of biodiversity (for example, Arroyo and Cavieres 1997). Long before objective assessments of existing protected areas can be realistically completed, very large areas of the world's remaining forests, especially in developing countries, will already have been submitted to some form of resource extraction as a result of economic pressures and social needs. This situation, added to the high biodiversity value of forests, suggests that it is time for scientists to pay greater attention to managed lands and to establish partnerships with sensitive users of the land, without whose collaboration the task of saving forest biodiversity will be very difficult.

Ecological Sustainability in Managed Forests—An Evolving Paradigm

Newly recognized goods and ecosystem services of forests, high biodiversity content, and increasing consciousness of global climatic change have led society to question how forests are being used worldwide. In particular, recreation, scenic, and related amenity values have become central to the public's perception of the role and value of native forests in both developed and developing countries. These societal concerns, in turn, have been paralleled by substantial changes in scientific perception of sustainability as applied to managed forests.

Throughout much of this century, the management of forests focused closely on the extraction of a specific ecosystem good, wood, in keeping with the concept of sustained yield, defined as the management of a resource for maximal continued production consistent with the maintenance of a constantly renewable stock. Such strong emphasis on a particular resource of strictly utilitarian interest, while saving trees of commercial interest, has been less kind to other organisms, as shown, for example, by reduction of the diversity of tree species (Jarvinen and others 1977) and the risk of extinction of as many as 700 species of plants and animals because of past forestry practices (Wright 1995) in Finland. Some 1,487 plants and animals in Sweden associated with forest habitats are considered to have reached threatened status as a result of widespread application of forestry practices (Berg and others 1994). Specialist invertebrates in Fennoscandian boreal forests tend to disappear from local clear cuts while forest generalist species and numerous open-habitat species appear (Niemelä 1997). At the genetic level, selective logging increases inbreeding in tropical dipterocarp forests (Murawski and others 1994).

In the late 1980s and early 1990s, as greater knowledge of ecosystem processes and biodiversity function in forests became available, the idea of ecosystem-based

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forest management began to take hold (Arroyo and others 1996; Franklin 1995). An ecosystem approach to forest management, which will be referred to here as ecological sustainability (Arroyo and others 1996), calls for a shift away from the traditional focus of sustainable yield to one in which all species and ecosystem processes are given consideration and sustainable yield remains an important goal. The recognition that numerous elements of biodiversity in forests are essential for maintaining productive capacity is central to the concept of ecological sustainability. For example, ectomycorrhizal fungi are responsible for aiding nitrogen uptake and fixation by tree species; many lichens fix atmospheric nitrogen; some bryophytes act as sinks for nitrogen leachate; arthropods aid in nutrient cycling of down wood and are major decomposers, chewers, shredders, predators, and food sources in forest streams and rivers; fungi are important decomposers of woody debris; and birds and mammals can be dispersal agents of fruit and seeds (Marcot 1997). Under an ecosystem approach to forest management, moreover, natural forest variability is recognized in developing silvicultural prescriptions, disturbance regimes are mimicked as far as possible in selecting harvesting and regeneration methods, and maintenance of landscape integrity is sought through establishment of protection forest and other types of buffers and the protection of aquatic ecosystems.

The adoption of ecosystem management also brought home the fact that adjacent ecosystems can be interconnected through such processes as nutrient cycling and biotic links, so that effects in any one ecosystem can have eventual repercussions at higher levels in the biodiversity hierarchy (landscape and regional). For example, plant species are sedentary, but their pollen and seeds are often transported by animals that live for part of their annual cycle in adjacent vegetation types. Thus, reduction in the nectar-feeding birds in a managed forest, besides affecting the bird species, will have effects on plant species in an adjacent ecosystem. Reduction of soil microorganisms can slow natural decay and so affect nutrient cycling, but there will also be secondary effects on water quality and aquatic life downstream. Such linkages and feedbacks between different levels of the biological hierarchy oblige consideration at the species, ecosystem, landscape, and regional levels and mean that landowners must be equally concerned with aquatic and other ecosystems, in addition to those under management.

In the early 1990s, as a result of increasing CO2 in the atmosphere because of the burning of fossil fuels and deforestation, the role of forests in maintenance of global carbon balance came into discussion, further modifying the expectations of ecological sustainability in managed forests. The conversion of forests to agricultural lands through burning releases carbon into the atmosphere; conversely, regenerating forests on managed or abandoned lands withdraw carbon. Although young and middle-aged forests accumulate more carbon than standing old-growth forests, the overall carbon balance in a harvested-forest landscape depends on the fate of wood harvested from old-growth forests (Houghton and others 1996). For example, mass-balance calculations for Pacific Northwest forests show that conversion of five million hectares of old-growth forest to younger plantations in Oregon and Washington in the last 100 years has produced a negative carbon balance because of the burning of slash and wood for fuel and the conversion of

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sawdust to paper with a short turnaround time for carbon release back into the atmosphere (Harmon and others 1990). Nevertheless, over broader areas of the Northern Hemisphere, the net effect of forest harvest and regrowth in temperate forests is considered to be zero to slightly positive (Houghton and others 1996). However, as projected from current land-use tendencies, the biomass and carbon stock in the equilibrium landscape that replaces Brazil's Amazonian forest after deforestation can be expected to have decreased by about 35% in relation to 1990 levels (Fearnside 1996). Under those conditions, collaboration in the regeneration and restoration of forests on managed lands in temperate areas and emphasis on wood products that permit carbon fixation for very long periods and conservation per se become important goals of sustainability in a managed-forest landscape.

As a result of rapid changes in the perception of the value of forests and equally rapid evolution of scientific ideas as to how forests should be managed, sustainable forestry has been steered in the direction of integrated resource management, or management that takes into account the multiple values of forests. Some aspects of those changes need to be kept squarely in perspective. Although many new measures are now being introduced into sustainable forestry for the protection of biodiversity and ecosystem processes, it has to be admitted that their effectiveness is largely unknown. The long-term studies required to test such effectiveness, which often must be on a spatial scale beyond the domain in which ecology is normally practiced, have not been undertaken to any great extent. It should be borne in mind that we have gone from an era of being concerned about a few tree species in the forest to one involving hundreds of species with different life-history properties, many different habitat requirements, and a demonstrated diversity of responses to harvesting at the population to regional levels (Arroyo and others 1996; Berg and others 1994; Jarvinen and others 1977; Murawski 1994; Niemelä 1997; Wright 1995). The task is not at all simple. One of the main problems is that describing the effects of forest harvesting on biodiversity has been the main focus until now, with far less emphasis on the more relevant manipulative research designed to find novel solutions to mitigate such effects. The most worthwhile studies clearly will be experiments conducted on managed lands themselves with untouched lands as controls. With those caveats in mind, an objective like biodiversity conservation with forest harvesting should be considered at the level of a working hypothesis. Until we know where the line is to be drawn—how much extraction of a commodity, such as wood, is possible while ecological and economic sustainability is maintained into perpetuity—the course of action must be to refine hypotheses by further observation and experiment, with the recognition that ecological sustainability is a long-range target.

One of the most urgent needs in the scientific domain is to develop predictive models for integrating various spatial scales to ascertain whether forests harvested on an ecosystem basis will recuperate to near their original ecological dynamics and biological content and aesthetic value and thereby be available for alternative uses—the ultimate aim of a dynamic interpretation of ecological sustainability. Knowledge of the limits that guarantee those last three conditions is important for developing countries, where the extraction of natural forest resources, even though undesired by large sectors of society, will often precede other, less

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resource-intensive uses, such as ecotourism and recreation (which, in requiring infrastructure and substantial new capital, are not always viable options at any given time). Determining these limits is particularly important in the Southern Hemisphere, where temperate forest is scarcer than in the Northern Hemisphere and thus not only is far more sensitive as a biome to inadequate management, but also, hectare for hectare, is under far greater demand for nonextractive uses. With respect to ecological sustainability, it is thus essential, first, to recognize that there are many scientific uncertainties and, second, to leave other options open, given that social perceptions of forest use will undoubtedly continue to change. A range of management strategies—from conservative levels of harvesting to the establishment of conservation safety networks, including permanent reserves, commitment to restoration and regeneration, long-term monitoring, and continued appraisal of results in the context of adaptive management—is essential to accommodate all the various situations. Application of the precautionary principle in combination with a multiple-use strategy has the advantage of allowing a landowner to switch to some alternative land use in the near future, if desired or if scientific findings suggest it to be the most appropriate pathway. The principles outlined here have been borne in mind by the group of Chilean scientists responsible for developing actions to conserve biodiversity in the Río Cóndor project, discussed below.

The Río Condór Sustainable-Forestry Project

The Río Cóndor sustainable-forestry project entails land holdings comprising 273,000 hectares, at 54°S in Tierra del Fuego, Chile, of which 54% is forested (figure 2). It is the first forestry project in Chile in which the principles of modern ecological sustainability have been assumed. It is perhaps one of the more advanced anywhere, in terms of the diversity of strategies implemented to protect biodiversity well before commencement of harvesting and the commitment to long-term monitoring and research to test the effectiveness of such strategies (Arroyo and others 1995; Arroyo and others 1996; Pickett 1996). The Río Cóndor project, owned by the Trillium Corporation, Bellingham, USA, and registered through Forestal Trillium Ltd. in Chile, has committed, through voluntary stewardship principles, to a sustainable project based on production of quality wood and other forestry products of added value, protection of biodiversity and ecosystem processes, recognition of potential forest values, and creation of employment and other social benefits for people in the area. Wood chips, a primary forest product, will not be produced, and exotic tree species will not be planted for commercial purposes.

In the absence of scientific information, measures will be taken to generate data and postpone any action that would lead to environmental degradation until such data are available. A comprehensive monitoring program—embracing regeneration levels, soil conditions, water quality, rare and endangered species, indicator exotic species, and guanaco and beaver populations—will be carried out by specialists hired specifically for that purpose. In accordance with a commitment to incorporate scientific knowledge and ensure environmental compliance, the Río Cóndor project established an independent scientific commission (ISC) of

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Figure 2
Location of four permanent reserves (dark shaded areas: Río Caleta, Canal Whiteside,
Lago Escondido, Lago Blanco-Kami reserves) on the Río Cóndor property, Tierra del Fuego.
Also shown (light shaded) are the two blocks of the Río Cóndor property (West
and East blocks). Contours are isohyets (lines joining points that receive equal amounts of
precipitation). Reserve boundaries were drawn on 25 March, 1999, by mutual agreement
between Chilean scientists and the owners of the Rio Condor property.

botanists, zoologists, and forest ecologist through contact with the Chilean Academy of Sciences and retains a land steward (Arroyo and others 1996). The ISC functioned under a protocol signed by David Syre, owner of the Río Cóndor holdings, which guaranteed its rights and independence. The ISC effected extensive baseline studies and participated actively in designing the conservation strategy and monitoring program. Species and generic richness in several groups of organisms for the entire Río Cóndor property is shown in figure 1.

The Río Cóndor Forests and Landscape

Forests on the Río Cóndor property belong to the circumantarctic biome and include deciduous types (pure Nothofagus pumilio, pure N. antarctica, and N. pumilio-N. antarctica), a mixed evergreen-deciduous type (N. betuloides-N. pumilio), a pure evergreen type (pure N. betuloides N. pumilio), and a mixed evergreen type (N. betuloides-Drimys winteri-Maytenus magellanica). Although Nothofagus as a genus dates back to pre-Cretaceous times, recent molecular work (Manos 1997)

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shows that the three subantarctic species in Tierra del Fuego evolved recently. The Río Cóndor forests were consolidated since 5,000 years ago as climate became wetter in the Holocene and allowed replacement of drier steppe vegetation with forests (Heusser 1993). According to criteria given by Spies (1997), most of the inland forests on the Río Cóndor property would be classified as old-growth. However, coastal forests have been heavily affected in the past by selective logging, burning, and grazing; cattle grazing is still practiced in many inland valleys today. Many watersheds in the Río Cóndor forests have been heavily affected by the American beaver, Castor canadensis, liberated in Tierra del Fuego in 1946.

The forests, dominated primarily by one or two tree species, often lack a shrub stratum; biodiversity is moderate; and there is a conspicuous absence of sensitive groups, such as amphibians, salamanders, and very large mammals that are wholly dependent on the forest habitat. The Río Cóndor forests are thus appropriate for putting the principles of ecological sustainability into practice with a broad and precautionary management strategy and with an acceptable risk at baseline conditions. The relative simplicity of the forests, moreover, makes future monitoring realistic for landowners with respect to cost and effort. There are other positive aspects for organizing a sustainable landscape. Forests are interspersed with substantial extensions of subantarctic peat bogs, alpine, and lakes; the landscape is diverse and scenically beautiful. Those last elements have been used to maximal advantage, as will be seen below.

Building a conservation network to protect biodiversity. In accordance with ecological baseline studies carried out by 17 research teams, facilitative reserves in harvested forest, core reserves, and an extensive buffer system have been established on the Río Cóndor property (Arroyo and others 1995, 1996).

Measures to maintain biodiversity in situ in productive areas. One of the most challenging tasks in sustainable forestry is designing a set of measures to maintain viable populations of organisms in the productive forest matrix itself. No matter how simple the forest and how benign the harvesting method, organisms will be affected during silvicultural intervention, either temporarily because of physical elimination of populations or for very long periods because of elimination of specialized habitats in old trees that characterize old-growth forest or changes in microclimate.

To maintain ecosystem productivity, measures to conserve microorganisms, fungi, lichens, and soil arthropods involved in decomposition are particularly important. That objective has been sought in the Río Cóndor project by modifying the traditional shelterwood harvesting method used in Nothofagus forests in Chile. In harvested stands, aggregates (Franklin and others 1997) (facilitative reserves—see Arroyo and others 1996 for this concept) of mature trees will be retained permanently throughout the rotation cycle in addition to the 30–50% tree cover retained initially. Such aggregates, which maintain the original soil conditions and a more natural microclimate, are expected to be important for conserving of epiphytic lichens and mosses, such birds as the magellanic woodpecker that depends on old trees, and microorganisms that depend on woody debris in an advanced

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stage of decomposition. Many shade-loving herbaceous vascular plants, lichens, and mosses and the five small mammal species in the forest habitat are expected to survive temporarily in these aggregates and then be dispersed back into forest after harvesting. Extensive studies in the Río Cóndor forests have revealed that a high proportion of vascular plant species are abiotically dispersed and genetically self-compatible and thus are well adapted for rapid recolonization of the harvested forest matrix, as are the 68 species of mosses and over 200 species of lichens that disperse via spores or asexual propagules. Comparisons of virgin, 1-year harvested, and 8-year harvested forest showed that, although abundance differences arose, many native species either survived in or were able to return to the shelterwood matrix even without the aid of aggregates. Aggregates will be distributed across the entire harvested-forest landscape and are expected to greatly ease connectivity between harvested forest and other components of the conservation network, such as stream buffers and core reserves. That last point is very important in the Río Cóndor landscape, where spatial differentiation of habitats and species turnover along elevational gradients is low, differentiation of a true riparian zone is lacking, and species richness can be higher in the more open and warmer ecotonal habitats than in forest. Bearing in mind that core reserves established in forestry projects will never be large enough to account for the minimal viable population size of all organisms, the inclusion of aggregates in the harvested matrix should extend the effective safety net of reserves. Dispersing facilitative reserves across the productive landscape, of course, places limitations on their size and on the types of organisms that they will protect. Where the tradeoff lies between number (determining coverage) and size (determining structure and microclimate) is a matter for further research.

Woody debris and residual wood from harvesting will be left on the forest floor after harvesting, and the litter layer will be disturbed as little as possible. Debris and residual wood are important not only for their nutrient content, but also as habitat for small mammals, the endangered red fox, and several species of habitat-sensitive ground birds. These components also provide anchorage for incoming seeds and spores and the shaded conditions preferred by native herbaceous species. Opening of the Tierra del Fuego forests through harvesting was seen to be accompanied by an increase in exotic plants, including such aggressive species as Taraxacum officinale; dealing with exotic plants will probably constitute one of the more difficult problems. Hundreds of species of arthropods were found in the litter layer in the Río Cóndor forests. The success of these measures for conserving biodiversity in productive areas in the Río Cóndor landscape should be enhanced by the rotation cycle of around 90–110 years, the fact that there are no intermediate successional trees in these simple forests, and the shelterwood harvesting method itself, which is far more benign than clear-cutting. The fairly long rotation cycle in relation to maximal tree age in mature stands on good sites (about 150–250 years), made possible on the Río Cóndor property because it is very large, is expected to facilitate the return to near old-growth conditions and enable repeated dispersal events back into harvested forest. The use of the shelterwood harvesting method to retain 30–50% of tree cover until regeneration is fully established will further ease connectivity between individual aggregates.

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Establishment of a system of permanent core reserves. Core reserves are a central part of the conservation strategy in the Río Cóndor project. These will perform multiple functions, including preservation of a representative sample of the main vegetation types on a regional scale; protection of specialist, rare, and endangered species; conservation of forest genetic material; protection of cultural values; provision of a resource for ecotourism and future research; and contribution to the aesthetic value of the Río Cóndor holdings. Core reserves will also act as facilitative reserves to replenish altered plant and animal populations in harvested forest in their own right, but this is expected to be more at the level of larger and more mobile organisms, such as mammals and birds, and a few bird-dispersed plant species.

Some 68,000 hectares—around 25% of the present holdings—has been assigned to preservation by the owners of the Río Cóndor property. The preserved land comprises four blocks (figure 2) that vary from an estimated 43,000-2,200 hectares. Reserves were selected through a process involving the participation of the ISC, an archaeologist, the present land steward of the Río Cóndor project, and Forestal Trillium Ltd. personnel (Arroyo and others 1996), after issue of a public statement on September 13, 1995, by the owners of the Río Cóndor property to create them. The reserves, established through a coarse-filter mode, include all five forest types on the Río Cóndor property and other nonforested vegetation types (matorral, subantarctic peat bogs, and high alpine) and span the east-west precipitation gradient across the Río Cóndor property. Together, the preserved areas contain 10,000 hectares of prime commercial-grade forest, and 17,000 hectares of unharvestable forest on steep slopes and of tree species not appropriate for harvesting. In establishing the Río Cóndor reserves, special attention was given to areas of high archaeological sensitivity along coastal areas and in the vicinity of the major lakes, in view of the 77 archaeological sites of Selk'nam affinity registered during baseline work. Additional considerations were continuity with other protected areas in the general region, such as Parque Nacional Tierra del Fuego, Argentina, boarding on the Lago Blanco-Kami Reserve; enhancement of areas of high aesthetic value, such as Fjord Almirantazgo (Canal Whiteside reserve); representation of altitudinal gradients; inclusion of parts of Atlantic- and Pacific-drained rivers (Lago Escondido reserve); and inclusion of watersheds ideal for long-term research on nutrient cycling (Lago Blanco-Kami reserve).

The reserves are expected to play an important role in protecting species in the face of regional conservation problems on the Río Cóndor property, such as Pseudalopex culpaeus (red fox, the largest mammal on the Río Cóndor property restricted to forest), Maytenus disticha and M. magellanica (two plant species with conservation problems), Campephilus magellanicus (magellanic woodpecker), several ground birds that require dark forest conditions, and a small number of vascular plants and small mammals endemic to Tierra del Fuego. The inclusion of important lakes, such as Lago Escondido, and part of Lago Blanco in the reserves places them well for the recreational activities and ecotourism contemplated in the Río Cóndor project.

Although 17% of 3.4 million hectares of Nothofagus pumilio forest in Chile is found in the National Protected Area System (CONAF 1997), the private Río

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Cóndor reserves constitute the only preserved areas of this forest type in the far southern extreme of its distribution in Chile. Río Cóndor reserves also capture one of the richest alpine areas in Tierra del Fuego (Arroyo and others 1996) and a wide range of subantarctic peat bogs with a rich flora including rare and marginally distributed species. In equaling in size Parque Nacional Tierra del Fuego in adjacent Argentina, the Río Cóndor reserves constitute an important contribution to regional conservation in southern South America and the largest private conservation effort in a managed landscape in Chile. Apart from their in situ sustainability benefits, establishment of the Río Cóndor reserves constitutes a good example of collaboration by private landowners to complement inadequate spatial coverage of protected areas in a state-protected area system.

Ecological buffers. In addition to more conventional buffers (10-m strips around peat bogs, 50-m strips along the Río Cóndor and other streams, a 100-m coastal buffer, and restriction of harvesting on most slopes of over 45% and above 450 m in elevation), all Nothofagus antarctica forest and 60,000 hectares of subantarctic peat bogs on the Río Cóndor property have been considered in a buffer mode. N. antarctica forest is a natural buffer because of its occurrence in a wide range of ecologically marginal and ecotonal conditions, such as between the 450- to 700-m-elevation tree limit and forests of commercial interest; at the edges of peat bogs, streams, and lakes; and between N. pumilio forest and wet steppe. Sharing many species found in harvestible forests and being scattered widely throughout the Río Cóndor landscape, preserved N. antarctica forest will greatly increase coverage of the facilitative matrix. Such habitat similarity highlights a trend in the Tierra del Fuego forests for wide habitat tolerances. Indeed, many forest-dwelling species can also be found in wet steppe, in the alpine, and in disturbed secondary habitats, which, by agreement, will not be disturbed to any extent and thus will also play a facilitative role. Such low habitat specificity reflects a distinctive colonizing character in the postglacial biota of Tierra del Fuego. This feature is very favorable for the conservation of biodiversity in a managed-forest landscape in that other nonexploited vegetation types will contribute directly to the sustainability of the targeted forests.

The mostly Sphagnum-dominated, rain-fed peat bogs on the Río Cóndor property cover 22% of the landscape and are found in a wide variety of physiographic situations, from valley bottoms to slopes of over 30%. They contain some 107 vascular plant species, including rare species like Tapeinia obscura (Iridaceae); a high cover of fleshy fruited, bird-consumed species; many nitrogen-fixing lichens; 10 species of birds; and nesting sites for native geese—but no native mammals. The rationale for keeping peat bogs out of the productive universe is compelling. They play a key role in hydrology and nutrient cycling by providing continuous water supply to the forests in a landscape that has very few free-flowing streams. Peat bogs are recognized carbon sinks, containing (in the boreal forest zone) 108 times as much carbon per hectare as a forest (Gorham 1991). The subantarctic peat bogs of Tierra del Fuego have accumulated carbon over the same general period as their Northern Hemisphere counterparts and to similar depths (Heusser 1993) and thus can be assumed, in the absence of more detailed information, to

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be important carbon sinks. Because of the magnitude of stored carbon in peat bogs, their potential for contributing to global warming through CO2 release by draining and harvesting is huge. It is probably not an exaggeration to state that the Río Cóndor property is centered on one of the largest carbon sinks in the Southern Hemisphere! The ISC submitted that the owners of the Río Cóndor property should seriously consider the possibility of placing these important subantarctic wetlands under RAMSAR in consideration of their regional hydrological significance and their role in maintaining global carbon balance.

Overview

In the Río Cóndor project, the scientific goal has been to combine protection with production in such a way as to ensure multiple sustainability benefits for a managed forested landscape at the stand, property, and regional levels and thus open the door to an integrated forestry project without foreclosing future options. The success of the series of actions that have been set into motion with the decided collaboration of the landowners at this remote location in the far southern temperate forests of South America depends heavily on maintaining the objectives of monitoring and future research. Such studies will have practical significance only if the knowledge generated is used to alter and implement management practices over time (Franklin 1995).

Acknowledgments

Original baseline research was financed by Forestal Trillium Ltd., Chile, to which gratitude is expressed. The willingness of David Syre, President, Trillium Corporation, USA, to engage in ecologically sustainable forestry and forest preservation is acknowledged. This manuscript was written during the tenure of an Endowed Chilean Presidential Science Chair.

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