Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements

Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited areas.An important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris var.mongolica Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth plantations.However,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly understood.In this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger plantations.In addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older plantation.Sensitivity of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic conductivities.Our study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with age.The results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying.

Disparities in tree mortality among plant functional types(PFTs)in a temperate forest:Insights into size-dependent and PFT-specific patterns

Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains incomplete.This study analysed size-dependent tree mortality in a temperate forest,encompassing 46 tree species and 32,565 individuals across different PFTs(i.e.,evergreen conifer vs.deciduous broadleaf species,shade-tolerant vs.shade-intolerant species).By employing all-subset regression procedures and logistic generalized linear mixed-effects models,we identified distinct mortality patterns influenced by biotic and abiotic factors.Our results showed a stable mortality patte rn in eve rgreen conifer species,contrasted by a declining pattern in deciduous broadleaf and shadetolerant,as well as shade-intolerant species,across size classes.The contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size,while the mortality of deciduous broadleaf species was mainly influenced by biotic factors,such as initial diameter at breast height(DBH)and conspecific negative density.For shade-tolerant species,the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence,whereas the mortality of large individuals was subjected to the combined effect of biotic(competition from neighbours)and abiotic factors(i.e.,convexity and pH).As for shade-intolerant species,competition from neighbours was found to be the main driver of tree mortality throughout their growth stages.Thus,these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns,which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems.

Tree species identity and interaction determine vertical forest structure in young planted forests measured by terrestrial laser scanning

Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree species.However,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in detail.Terrestrial laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented way.Therefore,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest structure.These plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition levels.We generated vertical plant profiles from the TLS data and derived six stand structural variables.Linear mixed models were used to test the effect of species richness on structural variables.Employing a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural variables.Our results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height diversity.Species identity on the other hand exhibited a significant impact on vertical forest structure across all sites.Species interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these interactions.Overall,our results highlighted the importance of considering both species identity and interaction effects in choosing suitable species combinations for forest management practices aimed at enhancing vertical forest structure.

Tree Planting:How Fast Can It Accelerate Post-fire Forest Restoration?——A Case Study in Northern Da Hinggan Mountains,China

In 1987,a catastrophic fire burned over 1330000 ha in the densely forested area of the Da Hinggan Mountains in the northeastern China.After the fire,intensive management including burned trunk harvesting and coniferous tree planting had been conducted to accelerate forest restoration.To study the long term effect of these activities on forest recovery,we used a simulation modeling approach to study long-term(300 years) forest dynamics under current planting and natural regeneration scenarios.Results indicate that under tree planting scenario in the severely burned area,the dominant species Dahurian larch(Larix gmelinii) can reach pre-fire level(60% of the area) within 20 years and the maximum abundance can reach nearly 90% within 100 years.While under natural regeneration scenario,it needs about 250 years to reach its pre-fire level.From the perspective of timber production,tree planting can bring twice as much timber volume as that under natural regeneration within 300 years,which is the average longevity of L.gmelinii.It needs about 70 years to reach the timber volume of pre-fire level under the planting scenario,whereas it requires at least 250 years to reach the timber volume of pre-fire level under natural regeneration scenario.Another dominant species Asian White birch(Betula platyphylla) responded negatively to the planting of coniferous species.In general,tree planting of coniferous species after fire can greatly accelerate forest restoration in terms of species abundance and target timber volume,with desirable ecological and economic returns.

Group planting of cherry (Prunus avium L.) fosters growth and tree quality is superior to conventional row planting in Germany

Wild cherry trees produce high-quality timber and provide multiple ecosystem services. However, planting and tending cherry stands in conventional rows are too costly. Therefore, low density group planting was trialled as an alternative to row planting. The mortality, growth, and quality of planted cherry trees were compared between the group and row planting. The influence of neighbourhood competition and light availability on growth and quality was studied. The group and row planting of cherry trees were established at a wind-thrown site in southwestern Germany in the year 2000. In group planting, five cherry seedlings and seven lime seedlings （Tilia cordata Mill.） were planted with a 1 x 1 m spacing. In total, 60 groups were planted per hectare with a 13 × 13 m spacing. In contrast, 3300 seedlings （2475 cherries and 825 limes） were planted per hectare in row planting with a 3 × 1 m spacing. Ten groups and plots （10 × 10 m） were randomly established in group and row planting stand, respectively. The survival rate, stability （height to diameter ratio）, diameter, and height growth were significantly higher in group planting. In the group plantings,40.5% of cherry trees had straight stems and 13.5% had a monopodial crown compared with 15% with straight stems and 2% with a monopodial crown in row planting. The proportion of dominant cherry trees in canopy was 49% in groups compared with 22% in rows. The length of branch free bole was significantly higher in cherries planted in groups than those grown in rows. Intra- and interspecific competition reduced the growth and stability of cherry trees in row planting, but not in group planting. Light availability did not cause any significant effects on growth and quality between group and row planting. This first study on cherry group planting indicates that the survival rate, growth, and tree quality were higher in groups than in rows at this early development stage. The competition by naturally born seedlings was an important reason for the difference in performance between group and row planting. This study will encourage forest practitioners to establish more cherry group planting trials on multiple sites to test the effectiveness of this alternative technique as a tool of regeneration and restoration silviculture.

Studies on Rubber (<i>Hevea brasiliensis</i>) Trees Exist Plant Type after Planting and Available Tapping Tree of Rubber Plantation in China

Existing plant types of rubber tree after planting and available tapping tree were investigated, and there were about 28 rubber plantations with different tapping years of 8 varieties “CATAS7-33-97”, “CATAS8-79”, “CATAS7-20-59”, “PR107”, “RRIM600”, “GT1”, “INA873”, “93-114”in South China. The results showed that there were six kinds of existing plant types of rubber tree after planting of rubber plantations, which were available tapping trees, wind damaged trees, cold damaged trees, tapping panel dryness trees, absent trees and weak trees, respectively. These data investigated also showed rubber trees under available tapping, stoppage due to tapping panel dryness, absence, wind damage, cold damage and weakness were counted and calculated and made up for 72.21%, 14.75%, 5.61%, 3.86%, 2.68% and 1.89%. Tapping panel dryness trees, wind damage and absent trees are major factors for the loss of tapping rubber trees in the rubber plantations. Of these investigated varieties, available tapping trees per 100 trees of rubber plantation of “PR107”at the 1st, 12th, 14th, 16th, 20th, 24th tapping year were 96, 67, 70, 75, 66, 46 trees in Hainan planting zone, respectively. Available tapping trees per 100 trees of rubber plantation of “RRIM600”at the 9th, 15th, 20th, 22nd tapping year were 88, 62, 55, 36 trees in Yunnan planting zone, respectively. Available tapping trees per 100 trees of rubber plantation of “93-114” at the 10th, 19th, tapping year were 94, 62 trees in Guangdong planting zone. These results showed that available tapping trees of rubber plantation decreased with increasing tapping age under different planting zones in China.

Analysis on the Growth Condition of Cunninghamia lanceolata Plantation in Lingnan Forest Farm

[Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old near-mature C.lanceolata plantation in Lingnan Forest Farm,Xiuning County,Huangshan City,Anhui Province was investigated and analyzed by sample plot survey.[Results]The average DBH value of the C.lanceolata plantation at the lower slope was the largest,24.7%and 19.2%higher than those at the upper and middle slopes,respectively.The average single plant wood volume at the lower slope was 47.6%and 49.1%higher than those in the upper and middle slopes,respectively.However,the average tree heights at various slope positions showed little difference.Meanwhile,all the indexes showed the phenomenon of semi-shady slope>sunny slope>shady slope under different slope directions.Among them,the effect of slope position on DBH was extremely significant,but the effect of slope direction on DBH was not significant,and slope position,slope direction and the interaction of slope direction and slope position had no significant effects on the tree height of the C.lanceolata plantation.In addition,slope direction and slope position had extremely significant effects on single plant wood volume.From the overall growth situation of the C.lanceolata plantation in Lingnan Forest Farm,the slope position factor had greater effects on various indexes of forest growth than the slope direction factor,mainly manifested in that the lower slope was better than the middle slope,and the middle slope position was better than the upper slope,while although slope direction had some effect on the growth of the C.lanceolata plantation,the influence degree was not as significant as that of slope position.[Conclusions]This study provides some reference for the adjustment and optimization,development and renewal of C.lanceolata plantation structure in the later period in this area,as well as some data support for other theoretical research on economic forests.

The Technology and Application of the Tree Planting Baseplate in Bare Rock Area

The ecological greening technology of the bare rock area of the arbor governance be-longs to the field of ecological environment restoration, selection of suitable arbors for vegetation restoration in bare rock area, vegetation recovery is the primary approach to governance the ecological environment of bare rock area. The reconstruction of bare rock area arbor-shrub-grass ecosystems is a global environmental science problem. Paying attention to Geological conditions with rich rock fissures and abundant groundwater in these fissures, following the idea to reconstruct ecosystem from arbor to shrub and grass and the principle one tree in a baseplate, authors develop a baseplate technique for tree planting in bare rock area. The baseplate includes the parent body, the root, and the cover to prevent evaporation. Especially, there are filled in nutritional soil for the parent body and the root, and the composition of nutritional soil are selected by test in laboratory, while optimal mix ratio of the composition is obtained. Then, application method in field is put forward. The technique can guarantee survival at early stage and growth in the later for tree planting in the baseplate. In particular, the root provides a good channel to guide tree roots into fissure rock and absorb groundwater in rock. Test in field shows that the baseplate technique has strong practicality in vegetation recovery of bare rock area. Test in field shows that the baseplate technique has strong practicality in vegetation recovery of bare rock area in the world.

Assessing Adaptability of Planted Trees Using Leaf Traits: A Case Study with Robinia pseudoacacia L. in the Loess Plateau, China

Leaf trait patterns and their variations with climate are interpreted as an adaptive adjustment to environment.This study assessed the adaptability of planted black locust (Robinia pseudoacacia L.) based on the analysis of leaf traits and the comparison of its leaf traits with inter-specific ones existing in the same area.We measured some water and N use related leaf traits: leaf dry mass per unit area (LMA) and N,P and K concentrations based on both leaf area (Narea,Parea and Karea) and leaf mass (Nmass,Pmass and Kmass) of R.pseudoacacia at 31 sites along a water stress gradient in North Shaanxi Province,China.The results show that leaves of R.pseudoacacia have high Nmass and low LMA in the study area.High Nmass and low LMA are usually representative of luxurious resource use,and will advance plant resource competitiveness in high-resource conditions.As a whole,LMA-nutrient relationships of R.pseudoacacia display patterns that are fairly similar to the inter-specific relationships in both direction and intensity.The tendency for LMA and Narea to increase with decreasing water availability and the positive correlation between LMA and Narea reflect the trend for R.pseudoacacia to enhance water use efficiency (WUE) at the expense of down-regulated photosynthetic N use efficiency (PNUE) and high construction cost in dry conditions.However,the positive relationship between LMA and Narea in high mean annual precipitation (MAP) area is either unremarkable or reversed with decreasing water availability.This implies a lower photosynthetic capacity and a higher construction cost for high-LMA leaves.The inter-specific relationship between LMA and Narea is positive and does not change with water availability.This difference between inter-species and intra-species may be due to more diversified anatomies and more specialised structures for inter-species than intra-species.The failure of R.pseudoacacia adaption to dry conditions reflected by LMA-Narea relationship may be partially responsible for the emergence of rampike and dwarf forms found frequently in dry conditions.Incorporating intrinsic characteristics of planted trees into vegetation restoration project will be instructive and meaningful for species selection.

Ecological stoichiometric comparison of plant-litter-soil system in mixed-species and monoculture plantations of Robinia pseudoacacia,Amygdalus davidiana,and Armeniaca sibirica in the Loess Hilly Region of China

We examined how afforestation patterns impact carbon(C),nitrogen(N),and phosphorus(P)stoichiometry in the plant-litter-soil system.Plant leaf,branch,stem,and root,litter,and soil samples were collected from mixedspecies plantations of Robinia pseudoacacia with Amygdalus davidiana(RPAD),R.pseudoacacia with Armeniaca sibirica(RPAS),and monocultures of R.pseudoacacia(RP),A.davidiana(AD),and A.sibirica(AS)in the Loess Hilly Region.The results showed that in mixed-species plantations,R.pseudoacacia had lower leaf N and P concentrations than in monocultures,while both A.davidiana and A.sibirica had higher leaf N and P concentrations.Soil P limited tree growth in both afforestation models.Mixing R.pseudoacacia with A.davidiana or A.sibirica reduced N-limitation during litter decomposition.Average soil total N and P concentrations were higher in RPAS than in RPAD,and both were higher than the corresponding monocultures.The average soil C:N ratio was the smallest in RPAS,while the average soil C:P ratio was larger in RPAS than in RP.A positive correlation between N and P concentrations,and between C:N and C:P ratios,was found in litter and all plant organs of mono-and mixedstands.Alternatively,for N concentration and C:N ratio,the correlations between plant(i.e.,leaf,branch,root)and litter and between plant and soil were inverse between plantation types.RPAD has an increased litter decomposition rate to release N and P,while RPAS has a faster rate of soil N mineralization.RPAD was the best plantation(mixed)to improve biogeochemical cycling,as soil nutrient restrictions,particularly for P-limitation,on trees growth were alleviated.This study thus provides insights into suitable tree selection and management by revealing C:N:P stoichiometry in the plant-litter-soil system under different afforestation patterns.

Effect of the seeds provenance and treatment on the germination rate and plants growth of four forest trees species of Cote d’Ivoire

The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.However,for some species,the numbers of surviving transplants has declined.Hence,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest restoration.In this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per provenance.Time to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or provenance.Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or provenance.The one exception was P.angolensis,for which no germination was recorded.Within species,some provenances produced higher germination percentages than did others.No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between provenances.Plant growth and morphological variability also depended greatly on provenance.Genetic factors might be implicated,therefore provenance trials should be undertaken and evaluated.Furthermore,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection.

Response of plant,litter,and soil C:N:P stoichiometry to growth stages in Quercus secondary forests on the Loess Plateau,China

Ecological stoichiometry is an important indicator of biogeochemical cycles and nutrient limitations in terrestrial ecosystems.However,little is known about the response of ecological stoichiometry to plant growth.In this study,carbon(C),nitrogen(N),and phosphorus(P)concentrations were evaluated in plant tissues(trees,shrubs,and herbs),litter,and soil of young(≤40-year-old),middle-aged(41–60-year-old),near-mature(61–80-year-old),and mature(81–120-year-old)Quercus secondary forests on the Loess Plateau,China.Vegetation composition,plant biomass,and C stock were determined to illustrate their interaction with stoichiometry.Only tree biomass C signifi cantly increased with stand development.Leaf N and trunk P concentrationsgenerally increased,but branch P decreased with growth stage.Fine roots had the highest C and P concentrations at the middle-aged stage.In contrast,shrubs,herbs,litter,and soil C:N:P stoichiometry did not change signifi cantly during stand development.Leaf N and P were positively correlated with soil C,N,P,and their ratios.However,there was no signifi cant correlation between litter and leaves in terms of C:N:P stoichiometry.A redundancy analysis showed that soil N best explained leaf N and P variance,and tree biomass and C stock were related to biotic factors such as tree age and shrub biomass.Hierarchical partitioning analysis indicated that,compared with soil or litter variables,stand age only accounted for a relatively small proportion of leaf C,N,and P variation.Thus,secondary Quercus ecosystems might have inherent ability to maintain sensitive responses of metabolically active organs to environmental factors during stand aging.The results of this work help to elucidate the biogeochemical cycling of secondary forest ecosystems in tree development,provide novel insights into the adaptation strategies of plants in diff erent organs and growth stages,and could be used to guide fertilization programs and optimize forest structure.

Evaluation of land suitability for Moringa oleifera tree cultivation by using Geospatial technology:The case of Dhidhessa Catchment,Abay Basin,Ethiopia

Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing worldwide.Therefore,this study aimed to assess suitableland for Moringa oleifera tree cultivation by using the integration of multi-criteria evaluation with geospatialtechnologies in the Dhidhessa catchment,western Ethiopia.Five parameters,namely:slope,land use and landcover(LULC),soil texture,land surface temperature,and rainfall data,were used in this study.The land suitabilityevaluation of Moringa oleifera is classified into three classes as highly suitable,moderately suitable,and notsuitable.The results revealed that,about 344.4 km2(12.2%)of the area is categorized into highly suitable,and2343.7 km2(83%)is moderately suitable for Moringa tree,whereas,137.2 km2(4.9%)is categorized as notsuitable for Moringa oleifera tree cultivation.Hence,based on the finding of the study,we suggested that farmers andother stakeholders can cultivate Moringa oleifera trees in the Dhidhessa catchment.

基于有限元模型的上海市常见园林树种抗风性研究

风害是园林植物受到的主要自然灾害之一,每年由于台风导致的园林树木断枝倒伏等现象频频发生,严重威胁了城市的生态安全。树木形态差异是影响树木稳定性的主要因子,以15种上海市常见园林树木为研究对象,探究不同冠层特征对树木稳定性影响及不同树形对分枝特征变化的敏感性。通过对研究树种的有限元建模进行树木自振和风致破坏模拟,计算得到树木的力学响应特征值,然后结合树木断裂的失效弯矩和树木弯矩在不同风速条件下的变化规律,预测树木断裂的临界风速,结合灾后实地调研结果,综合比较不同树种的抗风能力。

高速公路边坡生态防护技术及发展趋势分析

该文详细阐述生态防护在高速公路工程建设中的重要性,主要通过植被的蓄水、保肥和固土功能来加固和保护边坡。这种防护作用主要体现在根系的力学效应和植被的水文效应2个方面。同时,深入探讨公路路基边坡生态防护技术及其机理,并试图将这些知识应用于提升生态防护技术手段。为实现此目标,结合多年野外工作实践经验,以公路边坡植物防护技术为研究对象,从多角度对边坡植树种草防护技术的发展和生态防护机理进行深入分析。

南疆阿拉尔垦区密植棉花株高模拟研究

【目的】探讨新疆阿拉尔垦区密植条件下不同模型对棉花株高的预测效果。【方法】以株型差异较大的新陆中81号和塔河2号为试验材料,在阿拉尔垦区16000株·hm^(-2)密植条件下开展大田试验,用Python语言建立株高生长的逻辑斯谛(logistic)、冈珀茨(Gompertz)、理查德(Richards)方程和决策树机器学习预测模型,并对模型的预测精度进行分析。【结果】Logistic、Gompertz和Richards模型中,新陆中81号株高的均方根误差(root mean square error,RMSE)分别为8.38%、7.49%和7.52%,平均绝对误差(mean absolute error,MAE)分别为6.80%、5.79%和5.82%;塔河2号株高的RMSE分别为6.09%、4.77%和4.85%,MAE分别为4.52%、3.34%和3.36%。决策树机器学习方法中,新陆中81号与塔河2号株高的RMSE分别为6.91%和3.27%,MAE分别为5.04%和2.16%。Logistic、Gompertz和Richards生长方程以及决策树机器学习方法均能较好地预测密植条件下棉花株高的生长,但在预测精度上决策树机器学习方法总体上优于生长方程。【结论】基于决策树的机器学习方法不需要用数理统计知识解释模型,训练模型需要的数据量也较少,模拟精度更高,在模拟棉花株高方面有一定优势,是对传统生长方程的有益补充。

植物提取物养殖投入品树形图构建

植物提取物已成为饲料、饲料添加剂及兽用中药等养殖投入品的主要原料,为绿色养殖生产更加安全的动物源食品提供重要支撑。农业农村部于2019年7月发布了第194号公告,停止生产、进口、经营、使用除中药外的所有促生长类药物饲料添加剂品种,标志着我国进入“饲料端禁抗、养殖端减抗、产品端无抗或达标”时代。国家标准《植物提取物术语》和《植物提取物类饲料添加剂特征图谱制定技术要求》、农业农村部《植物提取物类饲料添加剂申报指南》和《促生长兽用中药安全性和有效性研究技术指导原则(征求意见稿)》等文件颁布为植物提取物在养殖行业的应用提供法规与技术保障。文章通过构建植物提取物养殖投入品业态链树形图,展示了种业、饲料、兽药、宠物产品及环境改良产品的业态逻辑和产业链关系,为养殖业科学规划分类产品开发提供有益参考。

重庆市典型园林树种抗日灼能力评价研究

气候变化背景下,全球高温热浪增加导致夏季高温时间和日照强度增加,植物日灼问题加剧,但目前针对园林植物抗日灼性的研究较少。以重庆市为例,通过模拟光照试验,对重庆市8种常见园林树种的抗日灼指数、抗日灼程度、净光合速率、蒸腾速率等指标进行测定,并采用主成分分析综合评价园林树种的抗日灼能力。结果表明:可从形态指标和生理指标两方面来评价园林植物的抗日灼能力;依据抗日灼能力得分的高低,将8种树种分为3种类型,依次为抗日灼能力强(三角枫、香樟、金桂)、抗日灼能力中等(银杏、五角枫、鸡爪槭)和抗日灼能力弱(红枫、银桂)。

多边形沙地挖坑植树机设计与转动性能分析

为了改善土地荒漠化的问题,降低植树造林对人力的依赖性,提高造林的效率和质量,设计一台用于沙地的多边形挖坑植树机。基于三维建模软件UG软件设计出一种适用于沙地的多边形挖坑植树机的几何模型,通过动力学分析推导出拉动旋转框架所需的拉力,并导入动力学仿真软件ADAMS进行了动力学仿真分析,得到旋转框架转动过程中质心位移曲线、绕转动轴力矩变化曲线和质心速度变化曲线,从而为旋转框架转动过程提供了分析的依据并验证方案的可行性。