Review of Plant Species Diversity in Managed Forests in Japan

Abstract

The effects of conifer plantation management and forest fragmentation on plant species diversity in Japan were reviewed. While most studies have demonstrated that the practice of thinning in coniferous plantations can enhance species diversity of naturally regenerated trees, such as broad-leaved trees, some have shown that thinning reduces plant species diversity through the direct physical disturbance to forests. In addition, plant species diversity in plantations has also been shown to be dependent on the distance from seed sources. Extensive forest fragmentation due to land use changes has occurred, particularly in forests near urban and suburban areas. Although the number of species per unit area in abandoned coppice forests is not clearly related to the extent of forest fragmentation, most species attributes (such as rare species) are negatively influenced by forest fragmentation. Some of the forests owned by shrines and temples in urban areas are similar to island forests and are relatively well protected from human disturbance. To more clearly understand and evaluate changes in biodiversity through forest management, elucidating the interactions between management and plant species diversity, species composition, and the ecological traits of various species is therefore necessary.

Why Forest Plantations Are Disputed? An Assessment of Locally Important Ecosystem Services from the Cryptomeria japonica Plantations in the Darjeeling Hills, India

“…As expected, the mixed stands have with a value of 2.15 (the highest Shannon index), but the difference with monocultures is not statistically significant. This might be the result of the absence of forest management activities in this study area as silvicultural treatments focusing on maintaining spatial and temporal diversity of environments usually have positive effects on species diversity of naturally regenerated plants [31][32][33].…”

Meta‐analysis of management effects on biodiversity in plantation and secondary forests of Japan

“…Japan's vast forest area and interest in conservation has generated copious empirical research on biodiversity responses to forest management interventions (Higuchi & Primack, 2009). Many of Japan's forestry studies, however, are published only in Japanese (Nagaike, 2012), reflecting the major barrier that language still presents to the global compilation and application of scientific knowledge (Amano et al, 2016). For example, just as for Japan, the majority of Central European forests are restricted to mountain areas, and have been exploited by clear-cutting and coppicing for millennia (Hilmers et al, 2018;Takeuchi et al, 2003).…”

“…The northern temperate forestry community stands to benefit from a synthesis of this rich literature, because of the wide practice and history throughout the temperate zone of management interventions exemplified by Japanese forest management. Although several narrative syntheses exist (Inoue, 2005;Nagaike, 2012;Yamaura et al, 2012), a robust systematic and quantitative synthesis is lacking. Interest in the revival of active management within "abandoned" secondary forests is increasing in Japan, as also in the United Kingdom and Europe (Takeuchi et al, 2003), while clear-cutting of plantations of the sort that predominates in North America (Lõhmus, Rosenvald, & Lõhmus, 2006) is also increasing in Japan amidst plans to increase domestic wood supply (Forestry Agency, 2017).…”

“…With its forests at various successional stages following a diversity of management practices, Japan's empirical literature offers the possibility of such understanding. Many of Japan's forestry studies, however, are published only in Japanese (Nagaike, 2012), reflecting the major barrier that language still presents to the global compilation and application of scientific knowledge (Amano et al, 2016). Indeed, given the extent of its forest area and richness of empirical research, it is apparent that Japanese studies are underrepresented in synthetic studies of forest management impacts.…”

“…Indeed, given the extent of its forest area and richness of empirical research, it is apparent that Japanese studies are underrepresented in synthetic studies of forest management impacts. Although several narrative syntheses exist (Inoue, 2005;Nagaike, 2012;Yamaura et al, 2012), a robust systematic and quantitative synthesis is lacking.…”