Pattern and Change of a Boreal Forest Landscape in Northeastern China

Abstract

We have studied the spatial and temporal patterns of a boreal forest landscape in northeastern China using aerial photographs from 1955 (before logging) through 1980. The primary forest landscape is a complex mosaic of four tree species, and three age classes for each tree species, for a total of eighteen patch types. In addition, the complexity of the primary forest landscape shows great variation in the number, size and areal composition of patches. The forest landscape has been fragmented obviously by deforestation. There is an average increase in patch number from 291.6 to 438.0 patches per 10 000 ha, and an average decrease in patch size from 34.3 to 22.8 ha. Most of the logged areas are small in size, an average of 10.9 ha. The areal composition of different patch types has been changed greatly since the 1950s. The hardwood forest areas (especially) have increased significantly (p = 0.05); coniferous Larix gmelinii decreased significantly (p = 0.05), and Pinus sylvestris var. mongolica remained about the same. The area of old-age class in the dominant species, Larix gmelinii, has decreased significantly (p = 0.05). In addition, young and middle age classes of all tree species occupy a larger proportion of the area in 1980 than in 1955. Due to deforestation and recovery, therefore, many of these ecosystems are in early succession stages.