Do subtropical seasonal forests in the Gran Chaco, Argentina, have a future?

摘要: While much information is available about tropical and temperate ecosystems, there a remarkably little as to land cover use changes in the subtropical biomes of world. Here, we quantify spatial patterns types at southern edge seasonally dry, Chaco forest South America during second half 20th century using vegetation map printed 1969 Landsat TM based digital produced 30 years later. Results show massive contraction forest; ca. 1.2 million ha original lowland mountain dry forests woodlands, 85% total, have been cleared only years. This loss 2.2% year 1 consistent with or even exceeds, global trends. Forest now persists fragments where was formerly continuous cover. Most undisturbed has converted pasture undergoing secondary succession. Today, these new types, resulting mainly from agricultural expansion, increased 10-fold represent commonest types. The intensity usage, possibly triggered by an increase annual rainfall last decades, accompanied practices relative decline rural population. 2004 Elsevier Ltd. All rights reserved.