This study aims to evaluate the effects of topographical factors on tree height growth and to classify stands of sugi (Cryptomeria japonica D.DON) into different site classes with Geographic Information System (GIS) analysis. To evaluate these effects, seventy-four plots (10 by 10m) were established in the study area. Calculations for all plots showed that the mean site index for northerly aspects is greater than for westerly and easterly aspects, and the lowest is for southerly aspects. Also, mean site indices are lower the closer the stand locations are to ridges. The lowest mean site indices are those of stands located within 10m of ridges. Next we classified sugi stands into three classes according to slope aspect and location on slope respectively. Integrating the two topographical factors with the growth data, sugi plantations were classified into four site classes: Class I , Class II, Class III and Class IV. GIS technology was used as an efficient means of performing geographical analysis, classifying sugi stands on the basis of topographical factors, and displaying the results.

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This paper features the utilization of satellite remote sensing in monitoring of forest area changes for timber resource management planning. Landsat TM data was applied to the monitoring and estimation of future forest area in Sungai Buloh Forest Reserve. Quantification of forest changes due to urbanization was performed using the dot technique with multi-temporal data taken in 1989, 1991 and 1994. On the present trends, the forest area is projected to be reduced to 1,450ha by the year 2000 and 615ha by 2005. The forest in Sungai Buloh will be completely exhausted by the year 2011 if forest conservation practices are not implemented.

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Modelling for this study was based on branch data from a sample of hinoki (Chamaecyparis obtusa) stands of different ages, silvicultural histories and varieties. Calculations of the relative crown curve of the exposed part of the crown were then made, based on branch tip position. We then investigated differences in relative exposed crown form due to tree age, silvicultural treatment and variety. It was concluded that the changes in crown length, diameter and slenderness ratio in the growing stages for Hinoki show similar tendencies to sugi (Cryptomeria japonica). It was confirmed that the difference of due to stand age, silviculture and variety. There are significant differences in the relative exposed crown form. The relative crown curve was calculated from a regression equation based on branch data for all the sample trees.

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We analyzed the relationship between current forest operations and the provision of roads in private forests in a mountain village area, as a basis for improved planning of forest road networks. The study area was Toei district in Aichi prefecture, and the forest operations studied involved the planting and tending (weeding, pruning, cleaning cutting, and thinning) of forests performed by the Forest Owners' Association from 1994 to 1996. Most of the work, both with respect to the number of operations and the area of each operation, involved the thinning and weeding of forest stands. Only a small amount of pruning and planting took place. Over the 3 years, there was little change in the nature of the operations. An analysis of the operations with respect to the access distance from the nearest road for each type of operation each year showed that the proportion of operations decreased as the access distance increased. There were a few discrepancies when the area of operations was considered, but the basic trend was essentially the same. All the different kinds of operations were concentrated within 300m of a road, and the average access distance each year was approximately 210m. This is shorter than the average distance of access across the whole of the forests in Toei, which was about 275m. This means that there are too few forest roads from the perspective of current forest operations. In order to resolve this problem, it is suggested that an additional 6m/ha of forest roads are needed immediately. This would nearly double the current forest road density of 7.0m/ha.

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The difference in estimation of the diffuse site factor due to different models of the spatial distribution of sky luminance was examined. The examined models were the uniform overcast sky (UOC) and standard overcast sky (SOC). The difference between the diffuse site factors for UOC (Ψ_UOC) and for SOC (Ψ_SOC) was 1.5% in average and ranged from -0.4% to 5.2%. A strongly positive correlation was observed between Ψ_UOC and Ψ_SOC: Ψ_SOC=1.109Ψ_UOC (n = 270, r = 0.999, p < 0.001). This shows that Ψ_SOC tends to be larger than Ψ_UOC and the difference increases with the increase in Ψ_UOC or Ψ_SOC. The difference is determined by three factors: 1) the decrease in gap fraction (gap ratio) with zenith angle; 2) the incident angle of cosine law; 3) the difference in spatial distribution of sky luminance.

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I proposed two new theoretical methods for estimating the crown closure through line sampling. These are an application of Masuyama's method for estimating an area based on a line sampling unit, using integral geometry. The first method is as follows: First, we establish a sample line of fixed length L in the stand, on the assumption that the crown projection area of all trees is included in an area of the stand T. Next, we define a continuous variable l_j which takes the value of that part of the length of the sample line which is included within the crown projection area of the j-th trees s_j. Then, its expectation is: E(l_j)=Ls_j /T. This holds true for the N trees: E(Σ^N_j=1l_j)=LΣ^N_j=1s_j /T. Dividing L into the sum of expectations of l_j (L≠0), we obtain: E(Σ^N_j=1l_j) /L=Σ^N_j=1s_j /T. Σ^N_j=1l_j /L is an unbiased estimator of crown closure. The second method is as follows: A sample line is established as in the first method, and a uniform random number is selected within the length of the line L. Next, a discrete variable φ_j is defined which takes the value 1 if the value of the random number is smaller than l_j, otherwise zero. Then, its expectation is: E(φ_j)=s_j /T. This holds true for the N trees: E(Σ^N_j=1φ_j)=Σ^N_j=1s_j /T. Σ^N_j=1φ_j is also an unbiased estimator of crown closure.

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The need to manage the resource in a more sustainable way and the changing demands of society on its forest are confronting the modern forester. Rapid population growth and development activities has caused high growth and development of urban land use and this result in the decrease of urban environmental quality and traffic disturbances. The objective of this study is to assess the usefulness of LANDSAT TM data in "green" cover mapping of a new township Putrajaya. A LANDSAT TM image of 126/58 (path/row) in Computer Compatible Tape (CCT) form, taken on June 14, 1996, with less than 5% cloud, was acquired for image processing and analysis using the PCI Software System (Version 6.2). Results indicated that band combination of 4-5-3 (FCC) was the best combination for the purpose of the study since it can clearly differentiate the "green" cover. A supervised classification of the image results in 12 classes of "green" cover classification. The overall accuracy obtained for this study was 70%. A total of four classes were allocated as potential sites for the development of a forest landscape map. Urban forestry landscaping using satellite remote sensing has the potential in Putrajaya because the area is still mostly surrounded by a "green" cover.

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