Land Use Dynamics and Landscape Change Pattern in a Mountain Watershed in Nepal 4.5 Study of landscape change pattern The number of land use plots under each land use class, their areas and perimeters in 1976, 1989, and 2000 were determined using information contained in the land use maps developed for respective periods. To study patchiness and degree of irregularity of different land use plots, a Shape Complexity Index (SCI; Kammerbauer and Ardon, 1999) was then calculated by dividing the average perimeter of land use plots by the average area. Higher SCI indicated more irregular patch forms. Change in the complexity of forest patches was further investigated at polygon level by comparing SCI of existing forest polygons with the SCI of “optimum” polygon shape (i.e. circle) of the same area. The polygon level investigation was necessary to avoid wrong interpretation of patchiness and complexity of forest patches arising from the assumption of normal distribution of polygon sizes across space (e.g. Kammerbauer and Ardon, 1999), which is not always true. 5. Results and Discussion 5.1 Changes in land use The land use maps for 1976, 1989, and 2000 are presented in Figure 2 and the area under the six land use classes during the three periods is shown in Table 3. Results show that broadleaf forest and conifer forest area increased while upland agriculture and grasslands declined continuously over the study period. Shrublands decreased during the first (1976-89) period but increased during the second (1989-00) period, while lowland agricultural area was expanded during the first period but the trend was reversed during the second period. A detail of losses and gains among the six land use classes over the study period is included in Table 4.  Figure 2: Land use in Upper Roshi Watershed in 1976 (top), 1989 (middle) and 2000 (bottom) Table 3: Comparison of areas under different land uses during the three periods
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