Journal of Forest Planning
Online ISSN : 2189-8316
Print ISSN : 1341-562X
28 巻
選択された号の論文の2件中1~2を表示しています
Articles
  • Pavithra Rangani Wijenayake, Takuya Hiroshima
    原稿種別: Article
    2022 年 28 巻 p. 1-13
    発行日: 2022年
    公開日: 2022/04/15
    [早期公開] 公開日: 2021/07/27
    ジャーナル フリー HTML

    Most survival analyses in forest science have been applied to planted forests where tree age usually had no dispersal on one stand, while there have been few reports about the age-based survival analyses in natural forests. The purpose of this study was to perform survival analyses of individual tree populations in natural forest stands to evaluate the matured states of forest stands. We used a combination of tree-ring and census data from the three preserved permanent plots in pan-mixed and sub-boreal natural forests, Hokkaido, northern Japan. All the living trees (diameter at breast height ≥ 5 cm in 1989) were targeted to identify tree ages using a RESISTOGRAPH. Periodical tree age data with a 10-year age class were used during the observation periods of 1989–1999, 1999–2009, and 2009–2019, and all the changes (i.e., death and new ingrowth) during the periods were recorded. In the analyses, first, we applied survival analyses to find out multi-temporal age distributions and non-parametric estimates. Secondly, we applied parametric Weibull distributions to calculate age-related metrics such as mean lifetime and mean age of stands. Finally, we evaluated these calculated metrics from the viewpoints of matured states of forest stands. The results of non-parametric survival analyses showed the age distribution of multi-modal and exponential shapes. We also found the differences in survival probabilities among periods were not significant except for one plot. We also compared the relationship among estimated mean lifetime, biological lifetime, and mean age of stands derived from parametric survival analyses with the Weibull distribution and evaluated the matured states of stands considering all these aspects. It was implied that the study stands might not get enough matured yet, but some plots showed further progress toward the matured state than others.

  • Chisato Tomimura Mishiba
    原稿種別: Article
    2022 年 28 巻 p. 14-28
    発行日: 2022年
    公開日: 2022/04/15
    ジャーナル フリー HTML

    A fair, democratic standard development process is central to ensuring the credibility and legitimacy of forest certifications built on private governance. This study reports the implementation of the multi-stakeholder process for developing the FSC national forest stewardship standard of Japan and analyzes the factors affecting the discussion for collective decision making. In particular, this study highlights the issue of radiological safety and indigenous peoples' rights, on which the discussion for developing certification requirements especially contested due to considerable gaps between the international standards and the existing legal framework or practices in Japan. The overall discussion was characterized by the general conflict of opinions between certificate holders advocating for pragmatic requirements in line with existing practice and the civil society supporting robust standards. The factors that are considered to have affected the FSC national standard development in Japan include stakeholder relations, presence of competing scheme, governance structure, FSC's value proposition, and some personal leadership. Among them, the pre-set value proposition seems to be the most powerful factor that sets the priority in decision-making and determines the outcome. For this multi-stakeholder process, revisiting the shared value of FSC resulted in setting a priority on the certification's credibility over market uptake and many certification requirements at the level of international standards. In the future, comparison with other multi-stakeholder processes conducted in different contexts will further reveal factors affecting the deliberative and decision-making process and outcome.

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