The rubber tree physiological and ecological process quantitatively described by using mathematical method is an important means to the analysis of rubber tree growth process and mechanism. The study on growth simulat...The rubber tree physiological and ecological process quantitatively described by using mathematical method is an important means to the analysis of rubber tree growth process and mechanism. The study on growth simulation model of rubber tree will lay the foundation for the application of rubber tree cultivation intelligent decision system. A Richards equation was formulated to describe the height and stem diameter growth dynamics of the annual rubber seedlings. An area correlation analysis was done according to the closeness of the observed parameters to the dynamic curve on the gray system composed of the seedling growth increment and the meteorological factors including aerial temperature, precipitation and solar radiation hours that influence upon the seedling growth. The results showed that rubber seedling response fitted the Richards equation quite well. The growth increment displayed a distinct alternation of 'slow—fast—slow— fast—slow' rhythm. The growth course of the seedlings might be partitioned into three periods of time by the sequential clustering analysis, namely pre-growing, fast-growing, late-growing stage. The tray correlation analysis revealed that air temperature had the most significant influence while precipitation had the least impact on height growth of the rubber seedlings. In conclusion, the air temperature had the most significant influence while solar radiation hours had the least impact on stem diameter growth of the rubber seedlings.展开更多
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The rubber tree physiological and ecological process quantitatively described by using mathematical method is an important means to the analysis of rubber tree growth process and mechanism. The study on growth simulation model of rubber tree will lay the foundation for the application of rubber tree cultivation intelligent decision system. A Richards equation was formulated to describe the height and stem diameter growth dynamics of the annual rubber seedlings. An area correlation analysis was done according to the closeness of the observed parameters to the dynamic curve on the gray system composed of the seedling growth increment and the meteorological factors including aerial temperature, precipitation and solar radiation hours that influence upon the seedling growth. The results showed that rubber seedling response fitted the Richards equation quite well. The growth increment displayed a distinct alternation of 'slow—fast—slow— fast—slow' rhythm. The growth course of the seedlings might be partitioned into three periods of time by the sequential clustering analysis, namely pre-growing, fast-growing, late-growing stage. The tray correlation analysis revealed that air temperature had the most significant influence while precipitation had the least impact on height growth of the rubber seedlings. In conclusion, the air temperature had the most significant influence while solar radiation hours had the least impact on stem diameter growth of the rubber seedlings.
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.
