Landscapes Forest and Global Change - ESA - Escola Superior ...

R.S. Moro & C.H Rocha 2010. A methodological proposal for restoration of forests in southern Brazil
275
2. Base for the proposal
Surveys were carried out in 0.01-ha plots laid out in a 30-yr-old 400 ha planted Araucaria
stand and a natural 320 ha Araucaria forest at Açungui National Forest in Campo Largo, State
of Paraná, Southern Brazil (25 o 10'41"S - 25 o 14'18"W). The dominant soil types in the region are
Inceptisol and Ultisol. The climate is classified as Cfb (under Koeppen’s climate classification
system), at elevations between 640 m and 905 m above sea level. Species composition and
several forest structure parameters are summarized in Table 1.
More than a half of the species found in both planted and natural Araucaria stands were
represented by Flacourtiaceae, Lauraceae and Myrtaceae. Sapindaceae and Euphorbiaceae were
found only in the natural Araucaria stand. The most abundant species found under the planted
Araucaria canopy were of Agavaceae, Flacourtiaceae, Sapindaceae, and Cyatheaceae families.
Under the natural Araucaria canopy, the most abundant families were Sapindaceae, Myrtaceae,
Canellaceae, and Euphorbiaceae. In terms of the Importance Value Index (IVI), the
Flacourtiaceae, Agavaceae, Cyatheaceae, Sapindaceae, and Fabaceae were the most important
families found under planted Araucaria stands while Sapindaceae, Myrtaceae, Flacourtiaceae,
and Araucariaceae were the most important families found under the natural forest canopy.
Araucaria trees produced similar height and crown width in both planted and natural
stands. The species with the highest relative density under the planted Araucaria stand were
Casearia sylvestris, Allophyllus edulis, Clethra scabra, Dalbergia brasiliensis, and Matayba
elaeagnoides (see figure 1). At shrub level, the stand was dominated by species such as
Cordyline dracaenoides, Cyathea corcovadensis, and Cyathea schanschin. The most frequent
species were Cordyline dracaenoides, Cyathea corcovadensis, Matayba elaeagnoides, Casearia
sylvestris, Casearia lasiophylla, Dalbergia brasiliensis, Clethra scabra, Cupania vernalis,
Casearia obliqua, Cedrella fissilis, Allophyllus edulis, Cyathea schanschin, Guatteria australis,
Casearia inaequilatera, Vitex megapotamica, Cabralea canjerana, and Myrcia rostrata.
In the natural stand (see figure 2), only Araucaria angustifolia and Matayba
elaeagnoides stood out over the canopy. The main species present in the stand were Matayba
elaeagnoides, Casearia sylvestris, Allophyllus edulis, Capsicodendron dinisii, Araucaria
angustifolia, and Eugenia uniflora. Among shrubs, the most frequent species were Mollinedia
clavigera, Sebastiania brasiliensis, and Myrcia hatschbachii.
Natural and planted Araucaria stands were similar in regard to both Shannon index and
evenness. Simpson index indicated that there is no dominance of a few species over the others
in either stand.
3. Benefits
Both natural and planted Araucaria stands showed similar phytosociological parameters.
Therefore, our suggestion is that planted Araucaria stands are suitable to be used in place of
Eucalyptus for conservation purposes.
Although Araucaria is highly site demanding, when planted on good quality sites, it can
produce as much as 50 m 3 /ha.yr. Commercial Araucaria timber volume production was higher
in the planted stand.
Eighteen-year-old planted Araucaria stands have shown high efficiency in conserving
soil organic carbon (Guedes 2005). Thus, wood stock was maintained in levels equivalent to
those in natural forests on good sites. Soil organic carbon was maintained on the site at rates
ranging from 23 to 56 g/kg, mostly as litter. In a 15-yr-old planted Araucaria stand, annual dry
matter accumulation in the litter varied from 5.0 to 6.4 Mg/ha (Koehler et al. 1987) while, in
natural forests, it could reach 5.9 to 8.3 Mg/ha (Fernandes and Backes 1998; Floss et al. 1999;
Figueiredo Filho et al. 2003).
The presence of endangered species in both types of Araucaria forests indicated the
ecological importance of the low density stand as a suitable alternative for the purpose of
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.