The purpose of this study was to assess the suitability of a classification model for the determination of damaged areas of windfall trees caused by typhoon No. 23 in October 2004. Data input to the classification model encompassed seven factors: altitude, slope direction, slope angle, flow accumulation, curvature, wetness index,and land use type. The output data had four possible results: no damage and three levels of damage. A classifier was used for five classification algorithms. The eighteen modules included eight decision tree modules, two rulebased modules, two instance-based modules, two Bayes modules, and four function-type modules. Data reduction by clustering was used to improve the efficiency of our analysis by removing unnecessary data from the training data. The constructed models were evaluated using “Sensitivity”and“Specificity”indexes. The GIS analysis showed that large amounts of windfall-tree damage were observed in valley landform areas, which indicated that the soil moisture conditions such as flow accumulation and wetness index were high. Many of these areas were located on north, northeast and northwest facing slopes. As a result of modeling by a classifier,the instance-based algorithm outputted a relatively good classification. When performing data reduction by clustering, the classification accuracy tended to improve. When making estimates for an entire study area with a reduced number of samples, we found that it was possible to produce an adequate simulation for situations where the training data was reduced to around one-tenth of the original information, without negatively affecting the model performance. We suggest that the index of the multiplication of “Sensitivity”and“Specificity”is effective as an indicator of model performance.

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Forest management practices influence the availability and quality of water by changing the characteristics of forest site, which in turn affect runoff, infiltration and evaporation rates. Therefore, understanding how forest vegetation impacts the relationship between rainfall and runoff over time is essential for sustainably managing forest for freshwater supplies, especially on remote islands due to their size, locations, geology and topography. However, the tool and /or data for studying a hydrological process of a particular site are/is often not available and even a basic hydrological process of a particular site is often little known. In this study, in the aim of improving our understanding of the hydrological process in an essential watershed on Okinawa Island, we use a simulation model that incorporates a kinematic wave approach to examine rainfall-runoff relationships. We tested the simulation model under various rainfall events to determine its accuracy for projecting runoff discharge. After comparing predicted and observed values, we found the model accurately predicted discharge under moderate and heavy precipitation, but were less accurate for lighter precipitation events. We also explored the modelʼs parameters to identify which values most accurately represent the watershedʼs environmental characteristics. We finally discussed the limitations and the provision for exploring various forest management in using our simulation model and implications for forest management.

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At the Conference of the Parties, in Nagoya (2010), 165 countries ratified the Convention on Biological Conservation, which states that marine and terrestrial protected areas should increase to 10% and 17%, respectively, by 2020. At the Conference, the Quebec government, independent of the Canadian government,decided to align its conservation targets with those ratified in Nagoya and stipulated that 12% of its territory will be under protected area status. Currently, only 9.16% of its territory is officially recognized in the network, and the schedule expires soon. The province of Quebec faces many issues that could make achieving these targets even more difficult: the habitats are highly fragmented; the stakeholders are numerous, with diverse interests within the territory; and the conservation sector has generally prioritized a strict conservation strategy. Considering the high expectations of the government and the short period of time left to achieve its objectives,how will it be possible to reach the Nagoya targets by 2020 while considering the socio-ecological factors? In particular, Quebec needs to expand the range of its conservation tools. A multipurpose protected area status is implementing in the province to achieve socioeconomic as well as conservation goals. Establishment of pilot projects within the territory will help in evaluating the protected area networkʼs adaptation to climate change. Even if they cover only 0.50% of the territory, these multi-purpose protected areas could reach the provincial targets. However, clear indicators for monitoring conservation objectives need to be developed to make sure that multipurpose status achieves ecological goals.

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