The 1995-96 wildfire season in Patagonia, Argentina (September – April) was the worst in nine years. A total of 120,000 ha of forest, wildland and steppe were affected by approximately 500 fires (Tab.1).
The reason for this dramatic development was the extended drought period with extremely high drought codes. Over five months, there was nearly no rainfall, e.g. the area around Esquel (Province of Chubut) had only five rain days with 28 mm precipitation from 24 October until 13 March. An extreme situation arose especially in the second half of January with multiple fire occurrences and large fires.
The forest area (native forest and reforestation) in the Patagonia region of Argentina forms a 70 km wide and 2200 km long strip, in places interrupted, along the Andes. The northern part, the provinces of Neuquén, Río Negro and Chubut, have a continental climate, and the southern part, Santa Cruz and Tierra del Fuego, a maritime one, with rains evenly distributed over the year. The distribution of forests under different climatic conditions is reflected in Table 1, column “native forest”. 95 percent of the wildland fires occurred in the three northern provinces and only 5 percent in the two southern provinces.
Tab.1. Wildfire statistics for September 1995 to April 1996 for the Patagonia Region of Argentina
* arranged from N to S ** 8 National Parks are distributed over all the are
82 percent of the affected surface corresponded to grasslands (steppe) especially in the northern province Neuqén. Within this vegetation type, the burned area per fire was the largest with more than 1,400 ha. In second position in terms of burned area are fires in native forest with about 20.000 ha in total.
It is noticeable is that the fires occurred more often in areas that were burned already before, about 40 years ago.
At present the succession vegetation reached a high development stage of shrubs, the prevailing species being Nothofagus antarctica. For these reasons fires unfortunately affect in increasing numbers old native forest or patches of old trees and leave behind larger and larger disturbed areas, which are the potential risk areas for future wildfires.
Only a few areas with shrubby vegetation and reforested areas were affected by fires.
The distribution of wildfire causes shows the dominating role of man made sources (more than 90 percent of all fires registered in Patagonia). But the origins of the fires varied strongly by regions. While almost all fires in the Río Negro area in the south were caused my men, climatic reasons (lightning) accounted for 46 percent of the fires in Neuquén province.
Tab.2. Causes of Wildfires in Patagonia
The largest wildfires happened in mountain native forests in remote areas with difficult access, but the more dangerous fires happened in the area of S.C. Bariloche (Rio Negro) due to arson. By 19 January 1996 problem fires were being reported from all three northern Patagonian provinces. Wildfires concentrated around the area of S.C. de Bariloche city, the main tourist resort in Andean Patagonia which called the attention and concern of the national government in Buenos Aires. The impromptu reaction of the central government and the lack of cooperation between local organizations and other national institutions (National Parks, military forces, etc.) led to poor and ineffective firefighting. Extreme fire conditions in neighbouring provinces Chubut and Neuquén restricted the availability of regional resources and mutual assistance.
A positive attitude of the national government towards the reorganisation of administrative responsibility for wildfires has been the corollary of this season’s fires. The responsibility will be allocated at the national level to enable a better response to wildfires in future.
From: Paul Cwielong
Centro de Investigación y Extensión
Forestal Andino Patagonico (CIEFAP)
Casilla de Correo 238
ARG – 9200 Esquel / Chubut