This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annual dynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote tnmk extension were simulated under 7 trea...This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annual dynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote tnmk extension were simulated under 7 treatments. The results showed that annual growth process could be modeled reliably by Richards' function. Eight growth parameters were developed including fast-growing point (t0), initialp oint of fast-growing period (tl), final point of fast-growing period (t2), fast-growing period (t), growth period (Dg), maximum day increment (AGRmax), maximum annual increment (A). Effects of pruning to promote trunk extension on growth parameters were analyzed. Paulownia remaining 3-6 lower branches after pruning had relatively longer fast-growing period (t), growth period (Dg), higher average day increment (Am), maximum day increment (AGRmax) and maximum annual increment (A). Therefore, lower diameter growth of original trunk did not decrease significantly, and upper diameter growth increased to some extent, Height and diameter growth of grafting trunk, and form ratio of grafting trunk were relatively higher. Total stock volume increment was improved significantly under the condition that stock volume increment of original trunk did not decrease.展开更多
文摘This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annual dynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote tnmk extension were simulated under 7 treatments. The results showed that annual growth process could be modeled reliably by Richards' function. Eight growth parameters were developed including fast-growing point (t0), initialp oint of fast-growing period (tl), final point of fast-growing period (t2), fast-growing period (t), growth period (Dg), maximum day increment (AGRmax), maximum annual increment (A). Effects of pruning to promote trunk extension on growth parameters were analyzed. Paulownia remaining 3-6 lower branches after pruning had relatively longer fast-growing period (t), growth period (Dg), higher average day increment (Am), maximum day increment (AGRmax) and maximum annual increment (A). Therefore, lower diameter growth of original trunk did not decrease significantly, and upper diameter growth increased to some extent, Height and diameter growth of grafting trunk, and form ratio of grafting trunk were relatively higher. Total stock volume increment was improved significantly under the condition that stock volume increment of original trunk did not decrease.
