The purpose of this study is to optimize the labor allocation in forestry work by using the stochastic PERT method (program evaluation and review technique) with groups of laborers in the forestry cooperatives. Forestry projects involve many activities some of which may run in parallel; others depend on one another. Forest managers are responsible for scheduling activities to avoid bottlenecks and meet project deadlines. Sometimes they must predict the most likely date for the completion of a project, taking into account all the things to be done and how they interact. The PERT method is designed to help project managers do this. The stochastic PERT method designed to evaluate the probability of meeting project deadlines, with given probability estimates of activity durations. The probability element of the PERT is emphasized in this paper and this is accomplished by using three estimates of duration for each activity: the most-likely duration, optimistic duration and pessimistic duration. Through the analysis of this study, the stochastic PERT was recognized to be very effective for labor allocation in forestry work. A PERT analysis of a project provides a realistic way to examine this in light of deadlines and resource limitations. It can help avoid major project cost overruns and it offers a clear mechanism for communicating project plans to workers of a project. The result of the paper shows the usefulness of the PERT method for the labor allocation in the forestry cooperatives.

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Most of the Larix Jeptolepis Gordon short-rotation forests have been assigned as environmental protection forests due to water shortage and other environmental reasons in northern China. Therefore, it has become necessary to change to long-rotation management. To understand the possibility of long-rotation management of Larix ]eptolepis Gordon forest, we investigated the old Larix leptolepis Gordon stands planted during the Manchuria dynasty in the Liaoning Prefecture, China. The stand density of the stands was higher than that of the stands of Larix leptolepis Gordon in Nagano. The volume ratio of trees larger then 30cm in DBH was more than 90% in each stand. The annual increment of DBH has not descended clearly. Therefore it is would be possible to improve DBH growth and obtain large trees, if long-rotation management is done properly. Since a number of useful broadleaf trees were found growing in the Larix leptolepis Gordon forests, they may be a induced to a mixed species forest after introducing the long-rotation management. In conclusion, it seems possible to change from short-rotation to long-rotation management for Larix leptolepis Gordon forest.

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To develop a monitoring system for the carbon sinks under the Kyoto Protocol, we examined a method of forest stand measurement using a 3D imaging sensor. The tree number, DBH and coordinate of trees were measured by the method of cylinder reconstruction, and the accuracy and precision were examined. The precision of coordinate was less than 8cm. In a short distance from the scanner, the precision of DBH was less than 1cm, and accuracy was less than 4.3cm. These results of coordinate and DBH had accuracy and precision sofficient to measure the forest stand as for as in a small area. Thus, this method is effective as a tool for remote sensing to investigate stands in small area and many sites. However, since the observed tree number was only 20-80% of the actual value, the estimated stem volume and carbon weight were not reliable. The next step of this study is to develop a method to remove the influence of non-counted trees, and combination with airborne sensing technology.

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