Regeneration Traits of Four Dominant Species in a Cool-Temperate Conifer-Hardwood Mixed Forest, Northern Japan

Assessing long-term changes in biomass of old-growth forests is critical in evaluating forest ecosystem functions under a changing climate. Long-term biomass changes are the result of accumulated short-term changes, which can be affected by endogenous processes such as gap filling in small-scale canopy openings. Here, we used 26 years (1993–2019) of repeated tree census data in an old-growth, cool-temperate, deciduous mixed forest that contains three topographic units (riparian, denuded slope, and terrace) in northern Japan to document decadal changes in aboveground biomass (AGB) and their processes in relation to endogenous processes and climatic factors. AGB increased steadily over the 26 years in all topographic units, but different tree species contributed to the increase among the topographic units. AGB gain within each topographic unit exceeded AGB loss via tree mortality in most of the measurement periods despite substantial temporal variation in AGB loss. At the local scale, variations in AGB gain were partially explained by compensating growth of trees around canopy gaps. Climate affected the local-scale AGB gain: the gain was larger in the measurement periods with higher mean temperature during the current summer but smaller in those with higher mean temperature during the previous autumn, synchronously in all topographic units. The decadal climate trends of warming are likely to have contributed to the steady increase in AGB in this old-growth forest.

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Single-tree management for high-value timber species in a cool-temperate mixed forest in northern Japan

International Journal of Biodiversity Science Ecosystems Services & Management ◽

10.1080/21513732.2016.1163734 ◽

2016 ◽

Vol 12 (1-2) ◽

pp. 74-82 ◽

Cited By ~ 5

Author(s):

Toshiaki Owari ◽

Koji Okamura ◽

Kenji Fukushi ◽

Hisatomi Kasahara ◽

Shinichi Tatsumi

Keyword(s):

Mixed Forest ◽

Timber Species ◽

Tree Management ◽

Single Tree ◽

Cool Temperate ◽

Temperate Mixed Forest ◽

Northern Japan

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Culture of larval spiny lobsters: a review of work done in northern Japan

Marine and Freshwater Research ◽

10.1071/mf97163 ◽

1997 ◽

Vol 48 (8) ◽

pp. 923 ◽

Cited By ~ 44

Author(s):

Jiro Kittaka

Keyword(s):

Water Quality ◽

Feeding Behaviour ◽

The Past ◽

Cool Temperate ◽

Spiny Lobsters ◽

Phyllosoma Larvae ◽

Work Done ◽

Plankton Feeders ◽

Palinurus Elephas ◽

Northern Japan

The method developed over the past decade in northern Japan to culture phyllosoma larvae of five species of principally cool-temperate spiny lobsters combines the features of upwelling water, co- cultured microalgae, and use of mussel gonad as food. The feeding behaviour of the phyllosomas shows that they are primarily predators with the pereiopods and secondarily plankton feeders with the maxillipeds and maxillae. Recent work has shown that contamination of culture water by microorganisms such as the fouling protozoans Vorticellaspp. can greatly reduce phyllosoma survival. The significance of co-cultures of microalgae in maintaining water quality is not yet fully understood. Newly hatched lavae of sailfin sandfish (Arctoscopus japonicus) is an excellent food for late-stage phyllosomas of Jasus verreauxi. About 5% of J. verreauxi phyllosomas metamorphosed into pueruli. Mortality during the puerulus stage was reduced by increasing the capacity of the culture tanks from 30 L to 100 L. A single Palinurus elephas phyllosoma raised in co-culture with diatoms and fed mussel gonad and A. japonicus larvae metamorphosed into a puerulus in 65 days after seven moults.

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Factors influencing early vegetation establishment following soil scarification in a mixed forest in northern Japan

Canadian Journal of Forest Research ◽

10.1139/x04-156 ◽

2005 ◽

Vol 35 (1) ◽

pp. 175-188 ◽

Cited By ~ 46

Author(s):

Toshiya Yoshida ◽

Yoko Iga ◽

Megumi Ozawa ◽

Mahoko Noguchi ◽

Hideaki Shibata

Keyword(s):

Species Diversity ◽

Plant Species ◽

Tree Species ◽

Mixed Forest ◽

Canopy Cover ◽

Total Density ◽

Dwarf Bamboo ◽

Negative Effects ◽

Tall Tree ◽

Northern Japan

Scarification is widely conducted in northern Japan to remove understory dwarf bamboo species in degraded forests for replacement with tree species. To explore ways to enhance species diversity and restoration of mixed forest at the treated site, we clarified the mechanisms that lead to compositional heterogeneity of plant species. We evaluated the relative importance of environmental factors (scarification properties, soil properties, light conditions, litter cover, and presence of canopy trees) for the demography of tall tree species (emergence, mortality, and growth) and whole vegetation structure (species diversity and composition) over the two growing seasons immediately following scarification. Of tall tree species, Betula spp. were dominant (60% in total density), followed by Abies sachalinensis (Fr. Schm.) Masters, Acer mono Maxim., and Phellodendron amurense Rupr. Light intensity was an important factor, having mostly negative effects on the demography of these species. Soil factors (e.g., nitrogen content, moisture) affected the demography mainly of shade-intolerant or hygrophilous species. In general, extreme environmental conditions led to the dominance of grasses, forbs, and lianas rather than tall trees. Maintenance of canopy cover, which limits light and supplies seeds as well as litter, proved to be most important in promoting plant species diversification on the scarification site.

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