• The Korean Journal of Ecology
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• v.18 no.3
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• pp.385-395
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• 1995

Species effects on soil nitrogen mineralization and nitrification in the top 15 cm of soil were evaluated using the buried-bag incubation method in three coniferous plantations in the Kwangneung Experimental Forest, Kyonggi Province. The plantations were established on a similar soil in 1927, and included Larix decidua, Pinus strobus, and Thuja occidentalis. Ten soil samples within each plantation were taken during an entire growing season (May 2~Oct. 30, 1994). Mean daily nitrogen mineralization rates during 45-day in situ soil incubations were significantly different among species and incubation dates. Growing season nitrogen mineralization also differed significantly among species and ranged from 47.7 mg N/kg soil for Larix decidua to 21.5 ma N/kg soil for Thuja occidentalis. Growing season nitrification differed significantly among species and comprised from 93% to 100% of the total growing season nitrogen mineralized. We speculated that organic matter contents and quality might control nitrogen mineralization and nitrification in these soils.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.532-538
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• 1996

GA4/7 spray, injection and several cultural treatments were applied to the greenhouse-grown potted hybrid larch(Larix decidua${\times}$leptolepis) grafts and field-grown European larch seedlings to induce early flowering. A treatment consisting of repeat-ed GA4/7 sprays, alone, was the most effective flower induction treatment for greenhouse-grown, potted larch grafts. Root pruning as a adjunct treatment did not show synergistic effects. Injection for potted grafts with GA4/7 was not useful approach in this study and it resulted in increased mortality. In the field experiment with 10-Year-old larch seedlings, repeated GA4/7 sprays in combination with root pruning or with plastic mulching appears to be useful and practical means for inducing larch flowers:

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.351-355
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• 1997

Adventitious shoots were induced from cambial tissue cultures of 3-year-old seedlings using BLG mineral salts medium supplemented with 10 mM glutamine and 30 mM sucrose. The optimum growth regulator level for bud induction was 4,5 $\mu$M BA which produced average 25.5 shoots per cambium segment. Induced buds were elongated on GD medium supplemented with 30 mM sucrose followed by LMG medium supplemented with 30 mM sucrose for further shoot elongation. Elongated shoots were rooted on half-strength GD medium containing $0.54 ;\mu\textrm{M}$ NAA with the frequency of 20%. This system proved the high morphogenic potential of cambial tissue in larch.