Dynamic Changes Of Biomass And Essential Oil Yield In Cinnamomum Camphora Coppice And Their Response To Harvesting Methods And Site Conditions

The cinnamomum camphora(Cinnamomum camphora var.Linaloolifera Fujita),is a kind of Chang guang tree species,which is the second class protected tree species in China.Linalool enjoys the reputation of "king of spices".The price of essential oil in the market is linalool > eucalyptus > camphor.At present,camphor wood resources are scarce and linalool production is low,which can not meet the needs of the global economic market to a great extent.Increasing biomass is an important means to increase essential oil yield of Cinnamomum camphora coppice.By studying the response of biomass and essential oil yield of Cinnamomum camphora coppice to harvest mode and site conditions,based on the shape of Cinnamomum camphora coppice.The accumulation and dynamic changes of biomass and essential oil yield of Cinnamomum camphora coppice under different site conditions were revealed by variance analysis,correlation analysis and regression analysis,and the optimum leaf /omass and essenti branch distribution ratio was explored.The relationship between morphological indexes and bial oil yield was established,and the prediction models of leaf area and leaf volume,leaf volume and biomass and essential oil yield were established,and the dynamics and distribution of stand in the future were predicted.The following results are obtained:1 In the annual dynamic change,the growth index and biomass of Cinnamomum camphora coppice were August > July > June > May > April,while the law of essential oil yield was July > August > June > May > April.The spatial distribution of biomass and essential oil yield of Cinnamomum camphora coppice was leaf > branch > dry,and the leaf/ branch ratio of biomass and essential oil yield of Cinnamomum camphora coppice was the highest in April.Conclusion in the monthly dynamic change,the indexes of Cinnamomum camphora coppice increased with the increase of temperature,and the premise of increasing the yield of essential oil was to control the leaf / branch ratio.Within a certain time range(July-August),the highest leaf oil content is the highest biomass = the highest essential oil.Output.2 Among the harvesting methods,the morphological indexes,biomass and essential oil yield of Cinnamomum camphora coppice were as follows: once a year > twice a year > not cut down in one year,and the spatial distribution of biomass and essential oil yield was leaf > branch > trunk.In biomass,the highest leaf / branch distribution ratio was2.36,and the highest leaf / branch oil distribution ratio was 19.62 in essential oil yield.The growth index of Cinnamomum camphora coppice,the biomass and essential oil yield of Cinnamomum camphora dwarf forest were 1.5m > 1m > 1.2m > 0.3m > 0.7m,and the spatial distribution of biomass of Cinnamomum camphora coppice was different.The highest leaf / branch ratio was 2.01 in the biomass of Cinnamomum camphora coppice,while the highest leaf / branch essential oil ratio in essential oil yield was 19.2.2 in the biomass of Cinnamomum camphora coppice,the highest leaf / branch essential oil ratio was 2.01.in the biomass of Cinnamomum camphora coppice,the highest leaf / branch essential oil ratio was 2.01.the highest stubble height was 0.3m.The results showed that the highest essential oil production in June and August was cut down once a year,and the best annual income model was twice a year.The cutting period of Cinnamomum camphora coppice is biennial,the best cutting mode is once a year from June to August,and the benefit is the best when the stubble height is 1.5 m.The spatial distribution of essential oil content and yield is leaf > branch > dry.The stubble height is 1.5 m.High efficiency is the best.3 In the site condition,the growth index,biomass and essential oil yield of Cinnamomum camphora coppice were obviously different in different slope positions,and the whole trend was downhill position > middle slope position > uphill position,and the spatial distribution of biomass and essential oil yield was leaf > branch > trunk.In the leaf/ branch ratio of biomass of Cinnamomum camphora coppice,the highest ratio of uphill position was 4.06.In the leaf / branch ratio of essential oil yield in Cinnamomum camphora coppice,the highest leaf / branch ratio was 65.57 in the middle slope.The index of Cinnamomum camphora coppice was sunny slope > shady slope,and the distribution regularity of biomass and essential oil yield of Cinnamomum camphora coppice was leaf >branch > dry.In the leaf / branch ratio of biomass of Cinnamomum camphora dwarf forest,the leaf / branch ratio of Cinnamomum camphora coppice was positive slope.The highest ratio was 5.60,while in the branch / leaf ratio of essential oil yield in Cinnamomum camphora coppice,the highest branch / leaf ratio in shady slope was 83.67.Conclusion it can be concluded that the economic yield of downhill position is higher in different slope positions.The influence of slope direction is greater than that of slope position,and the influence of sunny slope is higher than that of shady slope.4 The correlation degree between leaf area per plant and leaf volume can be described by LA=5.730 104.428 × Wl model,and the correlation degree between biomass and essential oil yield can be determined by model description,which can be described by SPB=-196.63 2.517 × SPO model.