Study On Management Width And Effect Of Strip Cutting Phyllostachys Edulis Forest

The large-scale and mechanized management of Phyllostachys edulis resources is an important way to solve the rising costs and intensive management of Phyllostachys edulis resources.Exploring the management mode of strip cutting of Phyllostachys edulis will break and innovate the traditional management mode of Phyllostachys edulis resources,provide theoretical basis and technical guidance for mechanized cutting management of Phyllostachys edulis resources,promote the utilization of Phyllostachys edulis resource advantages,increase the economic income of forest farmers,and play an important role in promoting rural revitalization.This study took Phyllostachys edulis forest in Yong’an City,Fujian Province as the research object,and set up five sample plots with different cutting widths（3m,6m,9m,12m,15m）of the same fertilization treatment and 27 sample plots with different fertilization treatment of the same width（9m）.The N:P₂O₅:K₂O ratio was 2:1:1.5,3:1:2,5:1:2.5（A1,A2,A3）and three fertilization amounts of 450,600,750 Kg/hm²（B1,B2,B3）were selected for two factor and three level fertilization experiments.Through two years of fertilization monitoring,combined with drone technology,the restoration effects of Phyllostachys edulis forests with different cutting widths and fertilization modes were studied,in order to provide auxiliary decision-making for the strip cutting management of Phyllostachys edulis.The main conclusions of the study are as follows:（1）Strip cutting reduces the quality of Phyllostachys edulis stands,while cutting with medium to high widths promotes the growth of stand density.Specifically,in 2021,the forest density in the 6m,9m,12m,and15m logging zones was higher than the control,with the highest forest density of 522 plants/hm² in the 15m logging zone;The unit cross-sectional area of the five logging belts is smaller than the control,and the highest unit cross-sectional area of the 9m logging belt is 29580.69 cm²/hm².In2022,the forest density of 9m and 12m logging belts increased,and the cross-sectional area of 3m,6m,and 9m logging belts increased.The forest density and cross-sectional area of 9m logging belt were the highest,with1593 plants/hm² and 99390.37 cm2/hm²,respectively.（2）The growth status of Hsinchu stands with different fertilization treatments is inconsistent,and partial fertilization can promote the growth of Hsinchu more.Specifically,in 2021,the stand density of A1B1,A1B2and A2B1 treatments was lower than that of the control,and the cross-sectional area of A1B3 and A3B1 treatments was higher than that of the control.The highest stand density and area per unit of A3B1 treatment were870 trees/hm² and 32515.86 cm²/hm².Specifically,in 2021,the stand density of A1B1,A1B2 and A2B1 treatments was lower than that of the control,and the cross-sectional area of A1B3 and A3B1 treatments was higher than that of the control.The highest stand density and area per unit of A3B1 treatment were 870 trees/hm² and 32515.86 cm²/hm².In 2022,the stand density and area of A2B2,A2B3,A3B1,A3B2 and A3B3 treatments were higher than the control.Among them,the highest stand density of A3B1 treatment was 1963 plants/hm²,and the highest unit area of A2B2treatment was 127,652.78cm²/hm².（3）According to the connotation of comprehensive evaluation of Phyllostachys edulis forest management effect,the density,height,spectral texture characteristics and spatial structure of Phyllostachys edulis forest were determined as remote sensing evaluation factors of Phyllostachys edulis management effect.The extraction results of each index are as follows:The comprehensive evaluation model of stand spectral texture is constructed by principal component analysis:the evaluation value of stand spectral texture=0.38 green vegetation index+0.36 red-green ratio vegetation index+0.32（red*NIR）+0.348（rededge/red）+0.222 information entropy+0.102 mean.In 2021,the average accuracy of stand density extraction in the study area was 90.8%,and in 2022,the average accuracy of stand density extraction in the study area was 87.87%.Based on the stand density data,the average stand height was obtained,and the determination coefficient（R²）of the linear fitting curve between the measured and estimated stand height was 0.7366.The comprehensive evaluation model of stand space is constructed by principal component analysis:the evaluation value of stand space structure=0.14 angular scale+0.289 size ratio+0.476 aggregation index+0.17 openness;The relative accuracy of measured and estimated values for angular scale,size ratio,aggregation index,and openness in 2021 is 89.09%,90.47%,80.75%,and84.33%,respectively;In 2022,they were 94.69%,92.59%,80.37%,and92.25%,respectively.The evaluation model of Phyllostachys edulis management effectiveness based on remote sensing evaluation index is as follows:the remote sensing evaluation value of Phyllostachys edulis forest management effectiveness=0.2559 stand spectral texture evaluation value+0.25 stand spatial structure evaluation value+0.2512 average height+0.2428 stand density;R² between the remote sensing evaluation value and the measured value of Phyllostachys edulis forest management effect is0.8323.（4）Based on the evaluation model of Phyllostachys edulis forest management effect,the evaluation values of Phyllostachys edulis forest management effect with the same fertilization treatment and different cutting widths and plots with the same cutting width and different fertilization treatments were obtained.The evaluation values of the five logging zones in 2021 are 6m>9m>12m>15m>3m,which are 0.42,0.41,0.28,0.18,and 0.15 respectively;In 2022,it was 0.69,0.67,0.66,0.64,and0.64 for 9m>6m>3m>12m>15m,respectively.The operational effectiveness evaluation values of A1B1,A1B3,A2B1,A2B3,A3B1,and A3B2 treatments in 2021 were higher than those of the control,with values of 0.45,0.45,0.53,0.44,0.53,and 0.46 respectively;In 2022,the operational effectiveness evaluation values of A2B2,A2B3,A3B1,A3B2,and A3B3 treatments were higher than the control,with values of 0.74,0.73,0.72,0.72,and 0.69,respectively.（5）The unit area,biomass and evaluation value of management effect of Phyllostachys edulis with different treatments were compared and analyzed.In 2021,the evaluation value of Phyllostachys edulis forest management effect was slightly different from the trend of unit area and biomass,while in 2022,the evaluation value of Phyllostachys edulis forest management effect was consistent with the trend of unit area.Under the same fertilization and different cutting widths,the best management effects of Phyllostachys edulis forest in 2021 and 2022 are 6m and 9m cutting belts respectively;Under the same width and different fertilization treatments,the ratio of N fertilizer,P fertilizer and K fertilizer which can effectively promote the growth of Phyllostachys edulis in 2021 and 2022is 2:1:1.5,the fertilization amount is 450Kg/hm² and the ratio is 3:1:2,and the fertilization amount is 600Kg/hm² respectively.（6）In 2020,2021 and 2022,the species richness of shrub layer under the forest first increased and decreased,while the species number of herb layer changed little.The species of shrub herbaceous layer recorded in the study area in three periods were 21 families,27 genera,31 species,36families,46 genera,49 species and 16 families,22 genera,24 species,mainly Rosaceae,Leguminosae,Myrsinaceae,Lauraceae,Gramineae and Pteridaceae.Compared with 2020,the cutting width of 12m and 15m can increase the species diversity and evenness of shrubs in the sample plot,while the cutting width of 3m and 6m will decrease the species diversity and evenness of shrubs in the sample plot,and the cutting belt of 9m and the control treatment have little influence.Different fertilization treatments will affect the shrub species and individual distribution uniformity in each cutting zone.