Windbreaks are important traditional methods for the adaptation and the passive environmental control against climate changes in rural settlements. However, changes in houses and lifestyle are among the main causes of their decreasing in the last years. Therefore, in order to reveal the actual trend of their decreasing and the reasons of their succession, this study adopts three research stages: 1) The quantity of windbreaks; 2) The arrangement of windbreaks; and 3) The spatial changes and the hearing survey in typical settlements. The approach of this study selected Kitaaizu village due to its particular location on a composite fan with Forty-nine (49) agricultural settlements surrounded by windbreaks.
1. The first stage is focused on the windbreaks quantity in order to clarify their decreasing use by comparing thirty-seven (37) settlements from aerial photographs of 1976 and 2011. Findings unveil changes of the average area ratio of windbreaks between 1976 with 19.9% and 2011 with 12.8%, with a decreasing ratio of 33.4%.
The main characteristic of this trend shows many settlements' ratio in 1976 is above 20% decreasing under the average in 2011, conversely to a reduced number of settlements from 1976 with a decreasing ratio trend. Thus, the research focuses on the relationship between the location and the ratio of settlements leading to two main results. The first shows a low decreasing ratio in settlements with flood records, whereas the second indicates a high ratio of windbreaks located in traditional settlements near the old roads in 1976.
2. The second stage is focused on classifying the form of the settlements and the arrangement of the windbreaks. The first point to consider for the classification is the two temporary types of distribution patterns recognized by the analysis of the aerial photograph from 1976. It is noticeable that one of the patterns is located outside of the composite settlements whereas the other is found dispersed inside of them. The aerial photographs also show a major number of windbreaks located on the outside patterns rather than the dispersed patterns. The second point to reveals the different decreasing trends of the distribution patterns by comparing the aerial photographs of 1976 and 2011. According to the comparison, the scenario from 1976 shows a higher decreasing trend of the outside patterns and evidences a clear decrease in the settlements with east-west and north-south distribution. In contrast, it is observable a lower decrease trend of the dispersed patterns within composite settlements.
3. The third stage involves the analysis of spatial changes and the hearing survey conducted after the field measurements of the studied settlements, which considers features and reasons of decreasing trends of the outside and the dispersed patterns. The objective is to evaluate the decreasing trend and decreasing ratio of the outside patterns from the windbreaks located on the north and west sides of the studied settlements. Additionally, the condition of the dispersed patterns is regarded from the settlements formed by the household's windbreaks on north and west sides. Hence, it is observable that not only windbreaks located in traditional housing lots tend to be succeeded but also the arrangement of the settlements which contributes to this process. As a result, the importance for the conservation of windbreaks is discussed from the standpoint of their relationship with the surroundings.
This paper reveals the actual state of the decreasing trend of windbreaks and the reasons of their succession. Also, it shows the subjects to be succeeded by the windbreaks. The main conclusion of this study is to present the importance of windbreaks from the standpoint of the settlements' scale.
