Plants allocate growth to different organs as a strategy to obtain limiting resources in different environments. Tree seeds that fall from a mother tree settle on, within, or below the forest floor and litter layer, and their relative positions can determine seedling biomass and nutrient allocation and ultimately affect survival to the sapling stage. However, how emerged seedling biomass and nutrients of each organ are affected by seeds in different positions is not yet completely understood in subtropical forests. Therefore, an experiment was conducted with seeds positioned above the litter layers of different thicknesses, on the forest floor, and beneath the litter layer, and the influences of seed position on biomass allocation and nutrient use efficiency of emerged seedlings of Castanopsis kawakamii was examined. The aim of the study was to determine the optimal seed position to promote regeneration. Allocation strategies were well coordinated in the emerged seedlings from different seed positions. Seedlings from seeds positioned above litter layers of different thicknesses (~40 and 80 g of litter) allocated growth to leaf tissue at the expense of root tissue (lower root mass fraction) and increased nitrogen (N) and phosphorus (P) accumulation and nutrient use efficiency. Seedlings from seeds positioned beneath a deep litter layer allocated most growth to roots (high root: shoot ratio, root mass fraction) to capture available resources at the expense of leaf growth. Seedlings from seeds positioned on the forest floor allocated most growth to roots to obtain limiting resources. Further, we also found that these traits were clustered into three groups based on trait similarity, and the cumulative interpretation rate was 74.2%. Thus, seed relative positions significantly affected seedling growth by altering the allocation of resources to different organs. The different strategies indicated that root N:P ratios (entropy weight vector was 0.078) and P nutrient use efficiency were essential factors affecting seedling growth in the subtropical forest. Of the seed positions analyzed, beneath a moderate litter layer (~40 g of litter) was the most suitable position for the growth and survival of Castanopsis seedlings. In future studies, field and lab experiments will be combined to reveal the mechanisms underlying forest regeneration.

The formation of a canopy gap results in changes to the microenvironment which, in turn, affect litter decomposition and nutrient release. However, the mechanisms underlying these effects in differently sized gaps and non-gaps remain poorly understood. To address this gap in knowledge, we selected three large gaps (above 150 m2), three medium gaps (50–100 m2), three small gaps (30–50 m2), and three non-gaps with basically the same site conditions. We then used the litter bag method to investigate leaf and branch litter decomposition over a year in a Castanopsis kawakamii natural forest with the aim of characterizing the litter mass remaining and the nutrient release in canopy gaps and non-gaps. Our results revealed that the remaining litter mass of leaf and branch litter was lower in medium gaps compared to other gaps, and leaf litter decomposed faster than branch litter. Environmental factors were identified as the primary drivers of total carbon and nitrogen release during litter decomposition. Gap size (canopy openness), taxonomic Margalef index, the Brillouin index of soil microbes, soil total nitrogen content, soil pH value, and average air temperature were identified as the main factors driving carbon and nitrogen release from branch litter. In the late decomposition stage, the taxonomic Pielou index, soil total potassium content, soil water content, and average relative air humidity were the main drivers of nutrient release from branch litter. The soil water content and average relative air humidity were also found to be the main factors affecting the nutrient release from leaf litter throughout the different stages of decomposition. Overall, our study highlights the impact of canopy gaps on microenvironmental variation, taxonomic community diversity, and soil microbial functional diversity and how these factors ultimately influence litter decomposition and nutrient release. Our findings provide an important foundation for further research into soil nutrient cycling in subtropical natural forests.

When seeds fallen from the mother trees, their initial contact physical environment was litter or soil. The dispersal positions of seeds (seeds positioned on top of the litter, the soil surface and beneath the litter) determine the process of their natural regeneration. We simulated three different dispersal positions of Castanopsis kawakamii, including seeds positioned on top of the litter (2 and 4 cm litter was placed below the seed layer), soil surface (without litter), and seeds beneath the litter (2, 4, 6 and 8 cm litter covers in the upper layer of seeds). We examined the effects of seed dispersal position on the chlorophyll fluorescence characteristics, non-structural carbohydrate, specific leaf area, leaf dry matter content and nutrient content of seedlings. The results showed that leaf nitrogen content per area of seedlings had significantly positive correlation with soluble sugar content, non-structural carbohydrate content, and negative correlation with specific leaf area across different dispersal positions. Seedlings of the moderate litter cover (2 and 4 cm) adopted resource acquisitive strategies by increasing relative chlorophyll content, soluble sugar content, non-structural carbohydrate content, leaf dry matter content, leaf nitrogen content and phosphorus contents per area, and decreasing specific leaf area to achieve their demands for rapid growth. Seedlings grew on soil surface and beneath the deep litter (6 and 8 cm) adopted the resource conservative strategies with higher leaf nitrogen content per mass and specific leaf area, lower leaf dry matter content, and non-structural carbohydrate content to intercept more effective light resources to compensate for the shady environment brought by deep litter. This would further decrease the probability of seedling mortality due to 'carbon starvation'. Seedlings under litter layer stored starch in leaf, and reduced the energy consumption of photosynthetic tissues (low PSⅡ maximum photochemical efficiency) to maintain seedling growth. Comprehensive analysis of entropy method indicated that low amount of litter cover (2 cm) significantly promoted seedling growth of C. kawakamii. In the future, we could regulate the thickness of litter layer to promote the growth and regeneration of C. kawakamii seedlings in natural forest.

林窗是森林更新演替的重要环节,揭示林窗环境下功能性状变异来源及其相对贡献,有助于阐明植物对林窗环境的响应.该研究以中亚热带格氏栲(Castanopsis kawakamii)天然林为对象,设置9个不同大小的林窗样地,运用方差分解探讨林窗、物种和个体对叶性状变异的相对贡献,采用线性回归分析不同大小林窗下群落性状变化及种间和种内性状变异的重要性.研究发现:(1)格氏栲天然林林窗植物比叶面积、叶干物质含量、叶厚和叶绿素含量由种间性状变异主导,叶氮含量由种内性状变异主导,叶磷含量受林窗大小影响最大.(2)群落叶磷含量与林窗大小具有显著正相关关系,土壤温度和水解氮含量对群落叶磷含量具有显著正效应,土壤有效磷含量具有显著负效应.(3)沿林冠开放度的群落叶磷含量变化主要由种内性状变异引起,优势种扮演着重要角色.结果表明,格氏栲天然林林窗环境下植物功能性状仍以种间性状变异为主(平均41％),但沿林窗环境梯度的群落性状变化主要源自种内性状变异,通过植物表型可塑性响应环境改变,优势种作用明显.

设计了三种含量(质量分数)分别为5％、10％和15％的微米氟化物,采用机械涂敷方法在ER5356铝合金焊丝表面制备了氟化物涂层,并与无涂层商用焊丝进行了熔化极气体保护焊(GMAW)工艺性对比.结果表明:微米氟化物涂层铝合金焊丝的焊缝中气孔率显著下降,当涂层中氟化物含量为10％时,焊丝抗气孔性最佳,相比于无涂层的铝合金焊丝,其焊缝气孔率降低约1.6％,接头抗拉强度达到280.79 MPa,提高约2.9％.表面涂敷氟化物涂层的焊丝通过改变电弧形态增加焊缝熔深,从而影响成形外观和力学性能.

种子从母株掉落于地面萌发后,其根系在不同散布位置(凋落物上层、土壤表层和凋落物下层)的生长形态影响幼苗定居及建成,而目前对其根系形态及生长特征的了解并不充分,限制了对幼苗根系在不同散布下适应策略的理解.为此,以格氏栲(Castanopsis kawakamii)为研究对象,通过模拟种子在凋落物中位置,设置凋落物上层(种子下层铺垫2 cm和4 cm凋落物,U2和U4处理)、土壤表层与凋落物下层(种子上层覆盖0、2、4、6 cm和8 cm凋落物,CK、D2、D4、D6和D8处理)等3种散布,探讨不同散布位置对格氏栲幼苗根系9个生长指标的影响.结果表明:(1)种子散布位置对幼苗根干物质质量具有显著影响,D2处理达最大值.(2)D2处理的幼苗根长、根表面积、根尖数、分枝数和比根长高于其它处理;根系平均直径在D6处理达最大值.(3)相关分析表明根长、根表面积、根尖数、分枝数和比根长与根系平均直径呈显著负相关关系.(4)对根系9个生长指标提取主成分后聚类为4个类群,D2与D4处理各划分一类;U2与U4处理划分一类,其余三个处理划分一类.综上所述,凋落物浅层覆盖(D2处理)适宜格氏栲根系生长;凋落物上层(U2和U4处理)种子萌生根根系受凋落物阻隔作用阻止其与土壤接触,而一旦根系与土壤接触,生长速度加快;土壤表层(CK处理)受地表光照及水分条件限制及凋落物深层覆盖(D6和D8处理)的幼苗受深层凋落物产生的机械阻碍力影响,通过调整对根干物质质量的投入和根系形态可塑性来适应种子散布.因此,在幼苗根系快速生长阶段,通过人为干扰方式,适当调节森林凋落物厚度,以促进格氏栲幼苗在林内更新.

[目的]了解格氏栲天然林凋落物对主要伴生种马尾松种子萌发与胚根生长的影响.[方法]通过探究天然林凋落物不同分解层及浓度浸提液对马尾松种子萌发和胚根生长的化感效应.[结果]表明:(1)影响马尾松种子萌发的主要因素是凋落物分解层,未、全分解层凋落物对马尾松种子萌发无显著作用;半分解层抑制发芽率和发芽指数,促进发芽势.(2)影响胚根生长的主要因素是浸提液浓度和作用时间,并受分解层-浓度-时间综合作用,未分解层对马尾松种子整个胚根生长期除1:5浓度呈抑制作用外,随浓度降低促进作用增强,1∶100浓度时促进作用最强;半分解层呈低浓度和高浓度促进,中间浓度抑制;全分解层总体璺促进作用,且随浓度降低促进作用减弱.(3)对应分析表明不同分解层-浓度对马尾松种子萌发无显著相关性,对胚根生长有显著相关性.[结论]不同分解层凋落物漫提液对马尾松种子萌发作用较弱,对胚根生长在低浓度下呈促进作用,高浓度未分解层浸提液有抑制作用,而半分解和全分解浸提液具有促进作用,凋落物化感作用更明显作用于胚根生长.

Forest gaps affect the soil microbial community structure and soil function by altering the ambient environment. This study aimed to explore the effects of environmental factors on soil microbial communities and enzyme activities in Castanopsis kawakamii forest gaps. The soil properties, soil enzyme activities, and microbial composition inferred by high-throughput sequencing were determined to quantify the soil eco-physiological functions. A redundancy analysis and linear model (LM) were further used to test the significance of forest-gap effects on soil microbial community structure and its function. The formation of gaps significantly increased the canopy openness (CO) and soil temperature (ST), and the small gaps (GS) and large gaps (GL) were the most conducive to the accumulation of soil total nutrients. Soil characteristics in GS provided a favorable environment for microbial growth, which promoted the soil microbes and function in these forest gaps. The soil physical–chemical properties in GM were relatively low and influenced its soil function, resulting in this gap size having the lowest enzyme activities. Forest gaps govern the soil microbiomes and soil function by regulating gap characteristics and soil properties. Meanwhile, the presence of dominant microorganisms promoted enzyme activities. These results could help further our understanding of the impact of forest gaps on the soil process and forest succession.

Aims: Environmental heterogeneity of forest gaps leads to variation in taxonomic and phylogenetic diversity of trees in these areas. Studying tree diversity in different sizes of forest gap communities can help to reveal the mechanisms that drive the formation and maintenance of biodiversity. This study took Castanopsis kawakamii gaps as the research object, and aimed to reveal the relationship between the taxonomic and phylogenetic diversity of plants and its environmental influence factors. Methods: We examined different sizes of forest gaps in a Castanopsis kawakamii natural forest as to study the taxonomic and phylogenetic diversity of plants, and used a generalized linear model (GLM) to explore the environmental factors driving the community assembly. Results: We found that the plant species and plant abundance in large gaps (> 200 m 2 ) were higher than those of medium gaps ([50 m 2 , 100 m 2 )), small gaps ([30 m 2 , 50 m 2 )) and non-gaps (100 m 2 ). The phylogenetic community structure of the large gaps tends to diverge, while that of the medium gaps, small gaps and non-gaps were affected by the combined effect of habitat filtering and competitive exclusion. The phylogenetic community diversity index (PD) was significantly positively correlated with species richness (SR), Margalef index and Shannon-Wiener index, which is related to the higher species composition of sparse species than dense species in forest gaps. Overall, forest gap size had a significantly positive effect on species diversity, and the soil total nitrogen content had a significantly positive effect on community phylogenetic diversity and phylogenetic structure. Conclusion: The formation of forest gaps increase the taxonomic and phylogenetic diversity of trees in natural forests, with gap size and soil total nitrogen jointly driving tree diversity in these natural forest gaps.

The survival rate of Castanopsis kawakamii from seed to seedling is relatively low, leading to difficulties in the regeneration of its natural forests. Forest gaps play a vital role in plant regeneration and biodiversity maintenance in forest ecosystems. Unfortunately, our understanding of the effects of gap size and within-gap position on the seed germination and radicle growth of C. kawakamii is still limited. In particular, our knowledge on the relationship between gap size and environmental factors and their influence on seed germination and radicle growth is incomplete. In the present study, we studied the influences of forest gaps and within-gap position on seed regeneration on the germination and radicle growth of an endangered species C. kawakamii in a subtropical natural forest in China. We selected three large gaps (LG, gap size above 200 m2), three medium gaps (MG, gap size 50-100 m2), three small gaps (SG, gap size 30-50 m2), and non-gap (NG), and planted the seeds of C. kawakamii in five positions within each gap. The results showed that (1) the influence of forest gaps on seed germination rate was, from highest to lowest, medium gaps (51%), non-gap (47%), small gaps (40%) and large gaps (17%), and the seed germination rate was the highest in all positions in medium gaps, with the exception of the east position. (2) Radicle length in forest gaps was, from highest to lowest, medium gaps, small gaps, large gaps and non-gap, and it was the highest in the east, south, west and north positions of medium gaps. (3) Canopy openness (gap size) and air temperature were the main factors influencing seed germination and radicle growth of C. kawakamii. We concluded that medium-sized gaps were the most suitable for seed germination and radicle growth of C. kawakamii, and they promote the regeneration of this endangered species in the investigated natural forest.

为了探讨凋落物物理阻隔对格氏栲天然林自然更新状况的影响,通过模拟野外凋落物覆盖,设置格氏栲种子上层覆盖厚0 cm(CK)、2 cm(D2)、4 cm(D4)、6 cm(D6)、8 cm(D8)及种子下层铺垫厚2 cm(U2)、4 cm(U4)凋落物等7个处理,分析凋落物覆盖方式及厚度对格氏栲种子萌发及胚根生长的影响.结果 表明:(1)凋落物覆盖方式及厚度对种子萌发进程存在显著影响.CK萌发持续时间最长,上层覆盖处理(D)次之,下层铺垫处理(U)的种子起始萌发时间显著滞后.(2)CK种子萌发率最高,其次D6处理发芽速度较快,发芽整齐;U处理较D处理的发芽率及发芽势均显著降低,且萌发抑制率显著增加.(3)D处理的种子胚根生长速度快,胚根长度大于CK;U处理的种子胚根生长速度呈先慢后快趋势.可见,凋落物是影响格氏栲种子萌发及胚根生长的重要因素,主要通过阻碍种子与土壤接触而抑制萌发,影响格氏栲林更新.

现代制造业要求焊接技术向智能化、连续化、绿色化发展,目前熔化极气体保护焊焊接过程中焊丝对导电嘴的磨损率过大,频繁地停工更换和清理零部件限制了熔化极气体保护焊自动化焊接的发展.电接触条件下的载流磨损是导致材料磨损率过大的重要原因,主要体现在两个方面:(1)电接触产生焦耳热,使环境温度大幅提高,局部温度甚至超过500℃,造成电接触材料发生软化;(2)电接触点的不断运动和变化导致产生微观电弧,造成局部材料的剧烈熔融和氧化.因电接触造成的电气磨损与机械磨损相互加剧,大幅缩短了导电嘴器件的使用寿命.接触电阻是产生焦耳热和微观电弧的关键因素,镀铜钢焊丝与导电嘴之间的接触电阻值约为1.6 mΩ,而对于无镀铜钢焊,该值提高到约2.5 mΩ.导电嘴使用寿命随接触电阻、焊接电流、送丝速度增大而缩短;法向接触载荷一方面增大机械磨损,另一方面减少电气磨损,因此对导电嘴寿命有着复杂影响.高强度、高导电性导电嘴材料有利于延长导电嘴使用寿命,利用双相析出沉淀强化的Cu-Cr-Zr系铜合金能在显著提高材料强度的同时尽可能地减少因合金固溶导致的电导率损失,与此同时,石墨基、粉末冶金及复合材料导电嘴也有一定的实用性和研究价值.光洁平整的焊丝表面有利于延长导电嘴使用寿命,在无镀铜焊丝表面制备润滑性涂层能进一步提升导电嘴磨损性能.由于焊接条件的特殊性,表面涂层需兼具高温稳定性、高导电性等特征,具有表面效应和小尺寸效应的固体润滑剂在这方面具有极大的优势和应用前景.本文综述了熔化极气体保护焊导电嘴载流磨损机理的研究进展,从工艺参数、导电嘴材料、焊丝表面状态等方面分析了影响导电嘴载流磨损的因素和延长导电嘴寿命的可行方法,对减少导电嘴磨损,延长其寿命,推动机器人自动化焊接和无镀铜实心焊丝研发制造具有一定的指导意义.

ObjectiveWe tested the effects of litter extracts from Castanopsis kawakamii natural forest on seed germination and radicle growth of coexistence species Chinese fir (Cunninghamia lanceolate), thus to explore the mechanism for the natural regeneration barrier of C. kawakamii species.MethodThe litter extracts of C. kawakamii natural forest were used as the source of allelochemicals, and the seeds of coexistence species C. lanceolate were used as the tested seeds. We analyzed the influence of litter extracts of undecomposed (branches, leaves, bark, and nutshells), semi-decomposed and fully decomposed layer with different concentrations on the germination rate, germination potential, germination index and radicle growth of C. lanceolate seeds.ResultThe undecomposed layer litter extract promoted the germination rate of C. lanceolate at the low concentration, and promoted or weakly inhibited the germination rate at high concentration. The germination potential and germination index were inhibited under each concentration. The litter extracts from semi-decomposed and the fully decomposed layer inhibited the germination index of C. lanceolate seeds, and the inhibition was stronger at the low concentrations (1∶50, 1∶100). The effects of undecomposed litter extracts on the radicle growth of C. lanceolate showed a double concentration effect of “low promotion and high inhibition”, and significant inhibition at high concentration (P < 0.05). At the 18th day under the leaf extract concentration of 1∶100, the radicle length increased by 14.3% compared with control, which significantly promoted the growth of C. lanceolate’s radicle length (P < 0.05). The litter extracts from the semi-decomposed layer promoted the radicle growth of C. lanceolate, but it was not significant. The litter extracts of the fully decomposed layer promoted the growth of C. lanceolate’s radicle length under the concentrations of 1∶5, 1∶10 and 1∶50, and the concentration of 1∶30 showed a significant inhibition (P < 0.05).ConclusionThe low concentration litter extracts of the C. kawakamii natural forest can generally promote or slightly inhibit the germination of C. lanceolate seed and promote its radicle growth, which promoted the regeneration of C. lanceolate and enhanced the competition between species in the forest, and thus indirectly lead to the suppression of natural regeneration of C. kawakamii.

[目的]林窗作为森林生态系统中的小尺度干扰,对森林土壤养分循环与微生物群落功能多样性维持起着重要作用.明确不同林窗大小土壤养分和微生物群落功能多样性及其季节动态响应机制,有助于改善格氏栲林土壤生态环境.[方法]以格氏栲天然林林窗为对象,采用Biolog微平板法,研究不同林窗大小土壤理化性质、碳源利用能力和代谢特征的季节动态变化规律.[结果](1)林窗生长季土壤温度、速效钾含量显著高于非生长季,pH值、速效磷含量显著低于非生长季.林窗形成促进了土壤pH值升高与速效钾积累,加速了微生物对碱解氮与速效磷的吸收和利用.(2)林窗生长季土壤微生物平均颜色变化率在培养的中后期显著高于非生长季.林窗内土壤微生物在生长季中主要利用碳源为羧酸、多聚物和氨基酸类,在非生长季中主要利用碳源为氨基酸类和羧酸类.(3)林窗土壤微生物功能多样性指数中,生长季Shannon-Wiener和Pielou指数显著高于非生长季,Simpson指数显著低于非生长季.林窗面积对生长季土壤微生物群落功能多样性指数影响不明显.非生长季小林窗Simpson指数最高,中林窗Shannon-Wiener指数和Pielou指数最高.(4)广义线性模型表明,林窗生长季的土壤温度和土壤速效钾含量升高有利于土壤微生物常见种优势度升高;非生长季土壤碱解氮含量降低,速效钾含量升高有利于微生物功能多样性升高.[结论]生长季林窗内土壤微生物群落功能多样性保持较高水平,土壤养分循环效率高;非生长季非林窗土壤环境有利于土壤微生物生长代谢,维持土壤生态系统功能.林窗形成导致土壤温度与速效养分含量的异质性是影响土壤微生物群落代谢特征和功能多样性的主要因素.

研究格氏栲(Castanopsis kawakamii)天然林不同部位(枝、叶、壳、皮)凋落物浸提液在0.200、0.100、0.050、0.025 g·mL-1含量下格氏栲种子萌发和胚根生长的化感效应.结果表明:(1)不同部位、不同浓度的凋落物浸提液对格氏栲种子发芽率、发芽势、发芽指数等影响的差异不显著,但与对照组相比各浸提组发芽指标存在显著化感作用.0.100 g·mL-1壳、枝凋落物浸提液对种子萌发的抑制作用最强,随着含量的降低抑制作用减弱;叶、皮凋落物高含量浸提液对种子萌发的抑制作用较强,低含量浸提液的抑制作用较弱.(2)不同部位凋落物浸提液含量对胚根生长的化感作用差异显著.枝、叶浸提液对胚根的影响总体上随含量的升高抑制作用减弱;高含量壳浸提液对胚根生长的抑制作用较弱,中等含量浸提液的抑制作用较强,低含量浸提液的抑制作用较弱;0.2 g·mL-1皮浸提液对胚根生长的抑制作用最强,随着含量的降低抑制作用减弱.(3)皮浸提液对种子发芽及胚根生长的抑制作用强,其他部位的影响弱.

Researches focused on soil carbon (C), nitrogen (N), and phosphorus (P) content and the stoichiometry characteristics along elevation gradients are important for effective management of forest ecosystems. Taking the soil of different elevations from 900 to 1700 m on Daiyun Mountain as the object, the elevation distribution of total C, N, and P in soil and their stoichiometry characteristics were studied. Also, the driving factors resulting in the spatial heterogeneity of soil stoichiometry are presented. The results show the following: (1) The average soil C and N content was 53.03 g·kg−1 and 3.82 g·kg−1, respectively. The content of C and N at high elevation was higher than that of at low elevation. Soil phosphorus fluctuated with elevation. (2) With increasing elevation, soil C:N ratio increased initially to 17.40 at elevation between 900–1000 m, and then decreased to 12.02 at elevation 1600 m. The changing trends of C:P and N:P were similar, and they all fluctuated with elevation. (3) Elevation, soil bulk density, and soil temperature were the main factors influencing the variation of soil C, N, and C:N. Soil pH and slope position were the driving factors for soil P, C:P, and N:P. The soil is rich in C and N, and has less total phosphorus on Daiyun Mountain. Raising the level of phosphate fertilizer appropriately can help to improve soil fertility and promote plant growth as well. In light of this information, in the near future, it will be necessary to conduct separation management of C, N, and P with regular monitoring systems to maintain favorable conditions for soil.

采用级间失稳率、 群落高度级分享度和Whittaker指数分析戴云山黄山松群落高度级结构随海拔梯度变化的特征.结果表明,随高度级增加,群落个体数和物种数均呈下降趋势.沿海拔梯度上升,黄山松群落整体失稳率大致呈上升趋势,且均为正值.黄山松种群的Ⅰ～ Ⅱ、 Ⅱ～ Ⅲ级间失稳率多为负值,而Ⅲ～ Ⅳ、 Ⅳ～ Ⅴ和Ⅴ～ Ⅵ为正值,种群优势地位明显.总体上,优势种对第Ⅰ高度级分享度最大,随高度级增加,种对高度级的分享度不断降低.黄山松群落高度级随海拔梯度变化其物种替代速率存在差异,Whittaker指数(βw)大多分布在0.4左右,高度级间物种变化幅度相对平稳.戴云山黄山松群落在垂直空间上物种分布连续性良好,处于稳定发展阶段,更新能力强.目前黄山松种群优势地位显著,高海拔区域优势地位更明显.黄山松在混交群落竞争中偏向K对策,以较多的成年大树来增强其在群落的优势地位.