Tree and woodland near the forest steppe ecotone of northern Patagonia near Confluencia, Argentina [Renzo Motta, Syn: Libocedrus chilensis D. Don Endlicher Silba ; Thuja chilensis D. Don; Thuja andina Poepp. Dioecious trees Castor et al.
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Tree and woodland near the forest steppe ecotone of northern Patagonia near Confluencia, Argentina [Renzo Motta, Syn: Libocedrus chilensis D. Don Endlicher Silba ; Thuja chilensis D. Don; Thuja andina Poepp. Dioecious trees Castor et al. Bark red-brown, peeling in threads. Shoots dense, flat. Leaves scale-like, lateral leaves much longer than facial ones, thick, curving inwards at the pointed apex, facial leaves blunt, with an indistinct gland on the upper surface and whitish bands on the lower surface.
Cones solitary, with 2 pairs of scales, the lower ones small and reflexed. Seeds small, unequally 2-winged, usually 4 to a cone Vidakovic Native to the mountains of S Chile and S Argentina. It occupies an exceptionally broad soil moisture gradient and, like many conifers, is exceptionally nitrogen-conservative Buamscha et al.
Forest structure has been strongly influenced by changing fire frequency and severity, with much more open stand structures during periods before European occupancy and during the early settlement period, followed by a coalescence of forest patches and increasing stand densities during the period of fire suppression most of the 20th Century.
Both fire and grazing by introduced large herbivores deer and cattle are affecting current stand recruitment Relva and Veblen , Kitzberger and Veblen , Veblen et al.
The northernmost populations of this species also occur, at the highest elevations reached by this species, in the Andes. These populations of Austrocedrus are growing under severe stress in low density, sparsely distributed stands Lequesne et al. Hardy to Zone 8 cold hardiness limit between Austrocedrus chilensis stands are in decline throughout the species' natural distribution, particularly among stands in poorly drained soils.
Affected trees may die rapidly but mortality is commonly preceded by several decades of severely restricted radial stem growth. Roots are often affected by one or more types of decay Filip and Rosso The problem was noted several decades ago but has only recently been found to be due to the introduced pathogen Phythophthora austrocedrae. There are said to be living trees more than 1, years old Lequesne et al.
Valmore C. LaMarche in It has been used in a variety of studies since the early s. Recently, old chronologies were used to develop a long reconstruction of drought severity in central Chile Lequesne et al.
Buamscha, G. Gobbi, M. Mazzarino, and F. Indicators of nitrogen conservation in Austrocedrus chilensis forests along a moisture gradient in Argentina. Forest Ecology and Management 3 : Castor, C. Cuevas, M. Arroyo, Z.
Rafii, R. Dodd and A. Austrocedrus chilensis D. Revista Chilena de Historia Natural 69 1 : Greslebin, A. Phytophthora austrocedrae. Forest Phytophthoras 1 1. Kitzberger, T. Fire-induced changes in northern Patagonian landscapes.
Landscape Ecology 14 1 : ABSTRACT: In northern Patagonia, Argentina we quantify changes in fire frequency along a gradient from mesic Nothofagus dombeyi forest to xeric woodlands of Austrocedrus chilensis at the steppe ecotone, and we examine patterns of vegetation change coincident with the changes in fire regimes across a range of spatial scales.
At a regional scale changes in land cover types are documented by comparing scale cover type maps from and Changes in landscape structure are analyzed by comparing vegetation patterns on scale aerial photographs taken in and Fire frequency peaked in the late nineteenth-century due to widespread burning and clearing of forests by European settlers late in the century.
Subsequently, fire frequency declined dramatically about due to the cessation of intentional fires and has remained low due to increasingly effective fire exclusion.
At a regional scale there has been a dramatic increase during the twentieth century in the proportion of forest cover relative to areas mapped as recent burns or shrublands in Remnant forest patches that survived the widespread late-nineteenth century burning have coalesced to form more continuous forest covers, and formerly continuous areas of shrublands have become dissected by forest.
Under reduced fire frequency there has been a shift in dominance from short-lived resprouting species mostly shrubs towards longer-lived species and obligate seed-dispersers such as Austrocedrus chilensis and Nothofagus dombeyi. Due to limited seed dispersal of these tree species, the spatial configuration of remnant forest patches plays a key role in subsequent changes in landscape pattern.
Lequesne, Carlos, J. Aravena, A. Lara and J. Central Chile drought reconstruction using tree-ring chronologies: A preliminary report. Relva, M. Impacts of introduced large herbivores on Austrocedrus chilensis forests in northern Patagonia, Argentina. Forest Ecology and Management : Don et Boutleje Cupressaceae is an endemic conifer of northern Patagonia, Argentina and south-central Chile, which has been affected by browsing by livestock and introduced deer especially red deer.
In northern Patagonia, we studied the effects of livestock and deer on the densities and heights of Austrocedrus saplings and on the structure and floristic composition of the vegetation in which this species occurs under a variety of different browsing regimes. Twenty-seven stands were sampled within the 'Compact' forest type i.
Principal components analysis PCA indicates that greater abundance of Austrocedrus saplings is associated with lower stand basal areas as expected for this relatively shade-intolerant species. Although browsing does not directly reduce the abundance of saplings, it has an important influence in terms of reducing height growth and producing deformed stems. Multiple correspondence analysis MCA indicates that saplings between 0.
Saplings of intermediate heights 0. High browsing indexes occur beneath canopy gaps, which are also sites of higher sapling densities. In the present study, sites characterized by heavy browsing also have a high cover of spiny shrubs Berberis spp. Where the preferred browse species, Schinus patagonicus , is abundant, Austrocedrus is less influenced by browsing. However, as browsing reduces the abundance of S. Austrocedrus stands that are in a phase of fine-scale gap-phase regeneration are the most susceptible to inhibition of tree regeneration by livestock and deer browsing.
In such stands, long-term persistence of a forest cover requires protection from large browsing animals. Urrutia, R. Lara, R. Villalba, L. Pezoa, C. Lequesne, E. Cuq and A. Streamflow reconstruction from tree-ring chronologies of Austrocedrus chilensis and Pilgerodendron uviferum in the Xth Region, Chile. Veblen, T. Kitzberger, R. Villalba, and J. Fire history in northern Patagonia: The roles of humans and climatic variation.
Ecological Monographs 69 1 : ABSTRACT: The effects of humans and climatic variation on fire history in northern Patagonia, Argentina, were examined by dating fire scars on trees at 21 sites in rain forests of Fitzroya cupressoides and xeric woodlands of Austrocedrus chilensis from 39 degrees to 43 degrees S latitude. Climatic variation associated with fires was analyzed on the basis of 20th-century observational records and tree ring proxy records of climatic variation since approximately AD In the Austrocedrus woodlands, fire frequency increases after about , coincident with greater use of the area by Native American hunters.
Increased burning, particularly in the zone of more mesic forests, is also strongly associated with forest clearing by European settlers from about to the early s. The marked decline in fire frequency during the 20th century coincides with both the demise of Native American hunters in the s and increasingly effective fire exclusion.
Tree ring reconstructions of regional precipitation and temperature show a steeply declining influence of climatic variability on fire occurrence from annual to multidecadal scales. It is the interannual variability in climate, rather than variations in average climatic conditions over longer periods, that strongly influences fire regimes in northern Patagonia.
Although climatic variability overrides human influences on fire regimes at an interannual scale, human activity is an equally important determinant of fire frequency at multidecadal scales. Years in which the southeast Pacific subtropical anticyclone is intense and located farther south than normal are years of enhanced drought and fire.
Similarly, years of widespread fire in northern Patagonia are associated with variations in mean sea level atmospheric pressure at about 50 degrees degrees S latitude in the South American-Antarctic Peninsula sector of the Southern Ocean, as reconstructed from tree rings for AD Precipitation and, hence, fire regimes in northern Patagonia are significantly influenced by high-latitude blocking events, which drive westerly cyclonic storms northward.
Variations at decadal to centennial time scales in major circulation features, such as ENSO activity and the meridionality of regional air flow at high latitudes, as well as changes in the degree of coupling of these features, influence climate and fire regimes of northern Patagonia. This series of volumes, privately printed, provides some of the most engaging descriptions of conifers ever published. Although they only treat species cultivated in the U.
Image of Austrocedrus chilensis. New Forum opened! Ask questions about this plant! Don Pic-Serm. About 3 Cupressaceae in Chile and 3 in our data base. Here you can buy the seeds of this species.