Plantation forestry in Misiones Argentina productivity and conservation Fernndez et al 1997 Montagnini et al 1997 1998 2001 Eibl et al 2000 Gobierno de la Provincia de Misiones Argentina 2003 a b

The province of Misiones in northeastern Argentina (25-28 °S, 53-56 °W, 100-800 m elevation), has an area of approximately 30,000 km2, less than 1% of the country total; however, it harbors almost 40% of the biodiversity and produces over 70% of the country's timber. The subtropical forest of Misiones formerly covered more than 100,000 km2 in regions of Argentina, Paraguay, and Brazil, but has been reduced to less than 10% of its original size. The Paranaense forest is one of the most diverse ecosystems of both Argentina and Paraguay. In its mature form, the Misiones forest contains an average of about 100 tree species per hectare. The species composition varies with geographical location: for example, the presence of Araucaria angustifolia (Bert.) O.K. (pino Paraná) in association with tree ferns is restricted in the northeast part of the province (at higher elevations), while Aspidosperma polyneuron Müll. Arg. (palo rosa) in association with palmito (Euterpe edulis) only occurs in the north. The complex forest structure includes trees attaining heights of up to 40 m, with no single species reaching importance values (average of relative abundance and relative frequency) of more than 8%, as well as a dense understory of lianas, tree ferns, palms and bamboos, small shrubs, and herbs.

The extent of subtropical forest in Misiones is currently about 1,800,000 ha, not including plantations. About 200 local producers own forest subjected to National Forest Management Plans, for a total area of forest under management of almost 500,000 ha. Timber extraction is carried out using diameter limits established for each individual species (see Chap. 5).

About one-third of the total area of forest is in national and state parks. There are a total of 53 Protected Areas of different categories, including national parks and reserves, 17 provincial parks, 16 private parks and wildlife refuges, natural monuments, two world heritage sites, one biosphere reserve, and one area of conservation and sustainable development: the Green Biological Corridor (Corredor Verde). In general, in these protected areas all the ecosystems of the Paranaense forest have been preserved.

A forest inventory completed in 1850 revealed by then a total area of natural forests of 2,600,000 ha, but as a result of forest exploitation and clearing for establishing plantations and agriculture, by 1977 this size was reduced to 1,222,000 ha. This was largely a result of government incentives for commercial plantations of pulpwood (principally Pinus elliotii and Pinus taeda), and cash crops such as soybeans, yerba mate (Ilex paraguariensis), and tea. The first tree plantations were established in the 1920s with the native Araucaria angustifolia. Pines were first planted in 1948, and today they dominate the Misiones landscape, mostly to the east of the province on the coast of the Paraná River. The first cellulose and paper plant was installed in the 1950s near the town of Eldorado on the Paraná River. The cellulose and paper industry soon consumed the natural and planted supplies of araucarias, and thus the plantations of pines and eucalypts were started to supply the fiber demand. By the mid-1980s, there were already over 150,000 ha of forest plantations, and as a consequence the forest cover of the province, including plantations, was increased to 67% by 1985. [The coverage was somewhat less (54%) in 2003.]

Due to the relatively low prices paid by the cellulose industries for pulp wood from the plantations, saw mills that cut timber for boards proliferated especially in the northern part of the province and spread later to the rest of the province. Advantages for the development of the pulp and timber industry in Misiones were the high yields and relatively short rotation times of plantation species; availability of high-quality labor; and natural forest resources of high diversity. In recent years, apart from its tradition as a province that supplies timber products for the rest of the country and for exports, Misiones has incorporated the concept of "multiple use" of its forest resources, including the use of non-timber forest products, as well as taking advantage of environmental services and recreational uses of forests.

Today, Misiones contains about 330,000 ha of planted forest. In 2003, Misiones' total production of roundwood from plantations was about 5,000,000 m3, representing about 70% of total production, the rest coming from natural forests. Most plantations consist of exotic species such as Pinus spp. (elliotii, taeda, and others), Melia azederach L. var. gigantea (paraiso), Eucalyptus spp., Paulownia spp., Toona ciliata, Grevillea robusta, and the native Araucaria angustifolia (Bert.) O.K.

The area cultivated with native tree species (Araucaria angustifolia and a few others) constitutes less than 10% of the total. This situation is partially due to insufficient information regarding adequate silvicultural methods for the establishment and management of native species. Yet, alternatives for land use are clearly necessary to support current economic and ecological needs: inappropriate land use and management with the proliferation of shifting agriculture or the use of inadequate soil management strategies in plantation management has often led to soil degradation and to subsequent abandonment of lands in the region.

In 1989, the Yale School of Forestry and Environmental Studies (FES) signed an agreement with the School of Forestry, National University of Misiones (UNAM), to carry out collaborative studies in reforestation and agro-forestry. Experimental pure and mixed plantations with native timber species on degraded land and enrichment experiments in degraded forests were established using native trees of economic value. Additionally, understanding of the use of native tree species in agroforestry combinations with commercial crops and their use in enrichment planting of degraded and secondary forest increased (see next sections in this chapter).

In addition, UNAM has recently started planting native tree species on degraded land in the Arroyo Pomar watershed, a tributary of a lake in the municipality of Eldorado. Local people with limited economic resources help care for and manage these plantations, which are expected to provide forest products and improve the environmental conditions (soil, water quality) of the watershed. The species used were chosen based on results from the Yale FES/UNAM research. The Pomar River restoration project will be extended by collaborating with other municipalities of the province of Misiones, to plant native species in degraded watersheds as part of communal projects to provide tree products and improve local environmental conditions.

Currently the difficult economic and social situation in Argentina (in spite of recent economic development) makes urgent the need for finding practical solutions to increase productivity and decrease negative impacts on existing resources. Local farmers are willing to try new alternatives for ecosystem restoration, some of which may include agroforestry combinations with the most common cash crops, and forest enrichment practices in impoverished secondary forest. Agrosilvopastoral systems with improved cattle breeds are helping many farmers to accelerate returns on plantations, especially pines.

Forestry development in the province of Misiones has contributed to increasing productivity and diversifying of the economy of the province while respecting environmental constraints. For example, plantations for pulp and timber keep expanding; however, they are generally established on relatively flat land. Most of the upper elevations of watersheds and riparian areas in the province are still covered by natural forest (Fig. 6.7). The relatively large proportion of forest in protected status ensures conservation of the diverse ecosystems of the region. Their use in ecotourism also contributes to diversifying the economy of the province. The challenge is to ensure that forest management respects the management plans; to check illegal logging; and to control encroachment of people on the forest, especially from the poorly protected borders with Brazil and Paraguay.

Fig. 6.7. Pine plantations usually occupy lower elevations in Misiones, Argentina, while natural forests are retained in the upper elevations and along rivers. (Photo: F. Montagnini)
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