Protracted drought during the late Holocene in the Lacandon rain forest,Mexico

A 3.4 m core was obtained for paleoecological analysis from Naja Lake in the Lacandon region of southeastern Mexico. This is the first study of the Lacandon area aimed at reconstructing late Holocene environmental history. The basal section of the core yielded an AMS date of 2020 ¹⁴C years b.p. The Naja pollen record shows that the lower montane rain forest characterized by Moraceae, Mimosoideae, Leguminosae and Combretaceae/Melastomataceae, coexisted with a pine-oak forest throughout the late Holocene. No Zea mays pollen was found during routine pollen counts, but the presence of both secondary pollen taxa and abundant charcoal particles suggest some degree of regional human impact. A marked increase in Pinus pollen, together with a reduction in lower montane rain forest taxa, is interpreted as evidence for a strong, protracted drought from 1260 to 730 ¹⁴C years b.p.     

Methodological and practical aspects of the presentation and interpretation of microscopic charcoal data from lake sediments

Analysis of microscopic charcoal particles is a useful part of palaeoecological research and is mostly used in conjunction with pollen analysis. However, there is considerable variation in the methodology of charcoal analyses. This paper considers various methods for the analysis of microscopic charcoal and the presentation of charcoal data in the context of a study of the upper sediments of two lakes Estonia. The results are evaluated by comparing both the pollen and charcoal data with documentary evidence of forest fires over the past 60 years. Indications of fires both varying in extent and at different distances from the lakes are evaluated in both the pollen and charcoal diagrams. The results suggest that the total area curve for charcoal particles per unit mass of sediment dry matter (cm² g⁻¹) provides the best indicator of forest fires. Fires in the study area are reflected differently in the charcoal and pollen curves. It is suggested that the charcoal data have the potential to indicate disturbance at a greater distance from the coring site than indicated by the pollen data. Received February 5, 2002 / Accepted August 14, 2002     

Palaeobotanical studies from tropical Africa: relevance to the evolution of forest, woodland and savannah biomes

Fossil plants provide data on climate, community composition and structure, all of which are relevant to the definition and recognition of biomes. Macrofossils reflect local vegetation, whereas pollen assemblages sample a larger area. The earliest solid evidence for angiosperm tropical rainforest in Africa is based primarily on Late Eocene to Late Oligocene (ca. 39-26 Myr ago) pollen assemblages from Cameroon, which are rich in forest families. Plant macrofossil assemblages from elsewhere in interior Africa for this time interval are rare, but new work at Chilga in the northwestern Ethiopian Highlands documents forest communities at 28 Myr ago. Initial results indicate botanical affinities with lowland West African forest. The earliest known woodland community in tropical Africa is dated at 46 Myr ago in northern Tanzania, as documented by leaves and fruits from lake deposits. The community around the lake was dominated by caesalpinioid legumes, but included Acacia, for which this, to my knowledge, is the earliest record. This community is structurally similar to modern miombo, although it is different at the generic level. The grass-dominated savannah biome began to expand in the Middle Miocene (16 Myr ago), and became widespread in the Late Miocene (ca. 8 Myr ago), as documented by pollen and carbon isotopes from both West and East Africa.     

Holocene pollen sequences as a record of competitive interactions among tree populations

The distributions of plant species in modern communities are often intensively studied in order to elucidate the basis of species richness and the maintenance of community structure. The Holocene pollen record provides an opportunity for an historical approach to the understanding of modern forest communities. Pollen data can provide evidence for the role of inter-specific competition in determining the composition of forest communities. The pollen data may point to those interactions where experiments to clarify the mechanisms of competition would be most relevant.     

峨眉山世界遗产地表土孢粉组合及其生态和古环境启示

通过峨眉山40个样点表土孢粉组合及其与植物群落之间关系的分析,结果表明:(1)花粉组合中木本植物含量(83.3%)占绝对优势,松属、杉科、桤木属、蔷薇科、桦属、枫杨属、蒿属、毛茛科和水龙骨科为主要孢粉类型;(2)中山常绿阔叶林花粉组合未能反映植被的群落特征;低山常绿阔叶林间人工次生林和常绿落叶阔叶混交林花粉组合只能反映母体植被的部分组成;针叶林花粉组合基本可以指示母体植被的群落特征;灌丛草甸花粉组合能够较好地反映母体植被的群落组成;针阔混交林花粉组合不仅可以很好地指示群落特征,花粉高含量类型还可以与植物群落优势种很好地对应;(3)主要花粉类型冷杉属、杜鹃花科、蔷薇科、珙桐属、槭属和盐肤木属具低代表性;枫杨属、栲属/柯属、桤木属和杉科花粉具超代表性;(4) DCA表明,通过花粉百分含量,能较好地区分人类扰动植被、阔叶林和针叶林,但常绿阔叶林、常绿落叶阔叶混交林和针阔混交林之间,针叶林和灌丛草甸之间难以区分;(5)利用孢粉学恢复热带亚热带常绿阔叶代表类群樟科群落和第三纪孑遗落叶阔叶属种珙桐群落时,受其主体植物花粉外壁薄,易破碎影响,原生植被优势种缺失;因此,孢粉实验改良和保存环境研究,与其他生物学指标(植物大化石和气孔器)综合分析在重建古植物群落中具有重要意义;(6)植物(如冷杉)花粉含量一定程度上能够指示其林分结构。本研究可为热带亚热带山地及相似地区利用孢粉学进行地质时期气候与环境重建提供理论支持和基础资料,并对植被生态恢复提供实践和参考。     

Identification of cultivated Pandanus and Colocasia in pollen records and the implications for the study of early agriculture in New Guinea

Pollen records from the island of New Guinea, spanning the last 60 000 years, show a vegetation system sensitive to global climate change and strongly influenced by anthropogenic activity. The evidence for anthropogenic activity in pollen diagrams has focused on indirect indicators such as forest clearance, burning and increases in arable weeds. Tracing individual cultivars has proven to be very difficult as the major cultivated plants, in this case dominated by root crops, have low pollen production, are insect-pollinated or are harvested before flowering occurs. The identification of some cultivars is further restricted by limited information on pollen morphology. The pollen morphology of selected species from two genera (Pandanus and Colocasia), known to include important cultivated species, have been studied. Five pollen taxa are recognised after examination by light microscopy and scanning electron microscopy. It is shown that these can be easily distinguished on the broad criteria of pollen class, grain size and size of echini. The taxonomic and dispersal characteristics of the pollen morphology of these taxa are discussed and the implications of improved identification of cultivated species in late Quaternary pollen records are considered.     

The vegetational history of the northern Apennines, Italy: information from three new sequences and a review of Regional vegetational change

Abstract. The results of pollen analysis and radiocarbon dating are presented from three northern Apennine sequences; Lago Padule in northern Tuscany and Lago Pratignano and Ospitale in the Emilia-Romagnan Apennines. This is the first detailed pollen stratigraphic information from sites in Emilia-Romagna and north Tuscany and extends eastwards the area from which information on vegetational history is available. The sequence from Lago Padule is one of the most complete Holocene records known from the northern Apennine region. Lago Pratignano has the deepest sequence of organic sediments (1544 cm) and the fastest rates of sediment accumulation (up to 28 cm per 100 years) providing the highest resolution record for the mid to late Holocene periods in the region. High rates of sedimentation have also occurred at Ospitale where organic sediments are 780 cm deep and began to form at approximately 5500 bp. The record from Lago Padule is compared with Holocene records from two nearby sites and a series of Regional Pollen Assemblage Zones is defined for the eastern area of the northern Apennines. The main features of vegetational change identified are: (i) a‘pioneer’phase of rapid forest development during the early Holocene followed by the establishment of an upper forest belt dominated by Abies, and a belt of mixed deciduous forest at lower altitudes; (ii) the appearance and rapid expansion of Fagus between approximately 5200 bp and 2900 bp forming a mixed Abies-Fagus association in the upper forest belt; and (iii) the overall reduction of forest cover, and dominance of Fagus in the arboreal vegetation from around 2900 bp. The scheme of Regional PAZs for the eastern area is used as a framework for the review of pollen stratigraphic information and radiocarbon dates from other sites in the northern Apennine region. Characteristics of pollen records which can be identified in sequences from across the region are identified and the chronology of similar changes in pollen stratigraphy is examined. The scheme of four regional PAZs for the Holocene period is shown to be valid for the entire northern Apennine region. The examination of a series of pollen records shows that Fagus appeared earlier in the western than the eastern part of the region during the mid Holocene and became dominant in the northern Apennine forests post 3000 bp. The impact of anthropogenic activity and climatic change on the spread and development of Fagus are discussed. The palynological evidence which is now available from the northern Apennines is compared with information for the region shown in the‘European pollen maps’of Huntley & Birks (1983). This study provides an updated review of the representation of different tree taxa in Holocene pollen records from the northern Apennines and illustrates the role of the northern Apennines as a refugium for trees during the Wurmian Lateglacial.     

东北长白山垂直林带下现代表土花粉与植被关系

在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析,同时将其结果作对应分析.结果表明,除个别样品,在长白山垂直植被带的孢粉组合中乔木花粉占优势,其中以松属和桦木属最多,在各植被带均有分布.松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中;桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带,但前者伴有耐寒、早的小灌丛杜鹃花属花粉,而在后者中则见有大量蕨类孢子.阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类孢子为特征.亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉.在高山苔原带孢粉组合中虽然乔木花粉略占优势,但极少或不见蕨类孢子,与其他植被带比较,草本植物和小灌丛花粉明鲜较多,其中杜鹃属花粉含量在草本中占优势,其中出现苔原带的指示花粉--仙女木属.     

东北长白山垂直林带下现代表土花粉与植被关系

在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析，同时将其结果作对应分析。结果表明，除个别样品，在长白山垂直植被带的孢粉组合中乔木花粉占优势，其中以松属和桦木属最多，在各植被带均有分布。松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中；桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带，但前者伴有耐寒、旱的小灌从杜鹃花属花粉，而在后者中则见有大量蕨类孢子。阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类饱子为特征。亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉。在高山苔原带孢粉组合中虽然乔木花粉略占优势，但极少或不见蕨类孢子，与其他植被带比较，草本植物和小灌丛花粉明鲜较多，其中杜鹃属花粉含量在草本中占优势，其中出现苔原带的指示花粉——仙女木属。     

Late Pleistocene and Holocene pollen stratigraphy at Lago di Vico, central Italy

A new pollen record from Lago di Vico (core V1) provides fundamental new information towards reconstruction of flora and vegetation history in central Italy during the last 90 000 years. The chronological framework is secured by seventeen AMS¹⁴C dates, one⁴⁰Ar/³⁹Ar date and tephra analyses. At the base of the pollen record, i.e. shortly after the⁴⁰Ar/³⁹Ar date 87 000±7000 B.P., three phases with significant expansion of trees are recorded in close succession. These forest phases, which stratigraphically correspond to St Germain II (and Ognon?) and precede pleniglacial steppe vegetation, are designated by the local names Etruria I, Etruria II and Etruria III. During the pleniglacial, a number of fluctuations of angiosperm mesophilous trees suggest the presence of tree refugia in the area. The lowest pollen concentration values are recorded at ca. 22 000 B.P. which corresponds with other pollen records from the region. The late-glacial is characterized by an expansion in the arboreal pollen curves that is less pronounced, however, than in other pollen profiles from Italy. The Holocene part of the profile is consistently dominated by deciduous oak pollen. No major changes in arboreal pollen composition are recorded but several marked and sudden declines of the tree pollen concentration suggest that the forest cover underwent dramatic changes. Clear evidence for human impact is recorded only when cultivated crops became important which dates to ca. 2630±95 B.P.     

南京紫金山山麓湖泊表层沉积物的孢粉分析*

本研究对南京紫金山山麓玄武湖和前湖共17个湖泊表层沉积物样品进行孢粉分析,旨在获得花粉组合新数据,揭示湖泊表层花粉与现生植被的关系,为开展第四纪湖泊地层孢粉学研究提供现代过程的参考.研究结果表明,花粉组合在剔除非自然分布的种植木本植物干扰花粉外,主要以木本花粉的松属(Pinus)和栎属(Quercus)占优势,其他常见木本植物有枫香属(Liquidambar)、栗属/栲属/柯属(Castanea/Castanopsis/Lithocarpus)、漆树科(Anacardiaceae)等.表土孢粉谱反映了研究区周边山地丘陵针叶、常绿-落叶阔叶林为主的植被,与现生北亚热带森林植被面貌对应良好.此外,陆生草本植物花粉主要是禾本科(Poaceae)和蒿属(Artemisia),湖泊湿生植物如水鳖属(Hydrocharis)、莎草科(Cyperaceae)等含量丰富.玄武湖与前湖中不同样点的主要木本植物花粉表现出优势类型高度一致、含量稳定、受采样位置的影响较小、指示地域植被类型的代表性较强等特点.通过对比南京地区已发表的紫金山及周边丘陵林下表土花粉分析结果,发现湖泊表土花粉组合受局部生境影响小,百分比含量较稳定,故其花粉信息在反映区域地带性植被的稳定性和可靠性方面更具优势.因此,开展表土花粉研究时应优先选择湖泊表层沉积物,藉此可提高基于孢粉重建区域地带性植被的代表性与可靠性.本研究结果为长江下游地区,尤其是南京地区解释第四纪孢粉组合与植被的对应关系提供了新数据和必要的现代过程参考.     

Mid-holocene sea-level and sedimentation interactions in the Dovey estuary area,wales

The stratigraphy of the mid-Holocene submerged forest in the Dovey estuary area, central Wales (dated at 6000-4700 radiocarbon years) is re-interpreted following a reassessment of previous investigations and an evaluation of new evidence from tree macro-remains and pollen. It is contendend that increased sedimentation rates induced by rapidly evolving coastal geomorphology, as opposed to a fall of mean sea-level,provide a simpler explanation for the “regression” sequence manifested by the forest beds.     

Pollen-vegetation richness and diversity relationships in the tropics

Tracking changes in biodiversity through time requires an understanding of the relationship between modern diversity and how this diversity is preserved in the fossil record. Fossil pollen is one way in which past vegetation diversity can be reconstructed. However, there is limited understanding of modern pollen-vegetation diversity relationships from biodiverse tropical ecosystems. Here, pollen (palynological) richness and diversity (Hill N₁) are compared with vegetation richness and diversity from forest and savannah ecosystems in the New World and Old World tropics (Neotropics and Palaeotropics). Modern pollen data were obtained from artificial pollen traps deployed in 1-ha vegetation study plots from which vegetation inventories had been completed in Bolivia and Ghana. Pollen counts were obtained from 15 to 22 traps per plot, and aggregated pollen sums for each plot were >?2,500. The palynological richness/diversity values from the Neotropics were moist evergreen forest?=?86/6.8, semi-deciduous dry forest?=?111/21.9, wooded savannah?=?138/31.5, and from the Palaeotropics wet evergreen forest?=?144/28.3, semi-deciduous moist forest?=?104/4.4, forest-savannah transition?=?121/14.1; the corresponding vegetation richness/diversity was 100/36.7, 80/38.7 and 71/39.4 (Neotropics), and 101/54.8, 87/45.5 and 71/34.5 (Palaeotropics). No consistent relationship was found between palynological richness/diversity, and plot vegetation richness/diversity, due to the differential influence of other factors such as landscape diversity, pollination strategy, and pollen source area. Palynological richness exceeded vegetation richness, while pollen diversity was lower than vegetation diversity. The relatively high global diversity of tropical vegetation was found to be reflected in the pollen rain.     

Three-dimensional reconstruction of an in-situ Miocene peat forest from the Lower Rhine Embayment, northwestern Germany—new methods in palaeovegetation analysis

Palaeovegetation reconstructions, particularly of fossil forests, are generally restricted to scant information on the taxonomic composition, relative abundance of individual taxa, or on tree density. We have developed new techniques for the analysis of stump horizons that result in a relatively detailed three-dimensional reconstruction of ancient forests. In addition, a rough estimate of their above-ground standing biomass can be calculated. These techniques are applied to an in-situ Miocene peat forest preserved in the Lower Rhine Embayment, northwestern Germany. In a study area of 2500 m², 476 stumps were mapped and used in the forest reconstruction. Additionally, pollen samples and leaf remains have been analysed. The peat forest consists primarily of conifers (in particular Taxodiaceae and Pinaceae) with Sciadopitys being the most common genus. The only angiosperms in the wood flora were palms, but in the pollen flora, evidence for the Myricaceae, Mastixiaceae, Ericaceae and a few other angiosperms is also present. The forest was relatively dense with 1904 trees/ha and a basal area of 164 m². Mean trunk diameter was 28 cm, while mean tree height is calculated to have been 9.9 m. Height, diameter and density distribution are illustrated using contour and three-dimensional surface plots. Estimated above ground biomass is 750 t/ha, but this value also includes dead or partly dead trees. This peat forest does not closely compare with previous reconstructions of Miocene peat forests. Its three dimensional structure and biomass differ from those of modern bald cypress swamps.     

江苏宜兴龙池山现代植被表土孢粉的初步研究

江苏宜兴龙池山森林自然保护区表土花粉分析结果表明,表土孢粉植物群主要以栎属(Quercus)、松属(Pinus)、青冈属(Cyclobalanopsis)、栲属(Castanopsis)/柯属(Lithocarpus)、栗属(Castanea)占优势的木本植物组成,混生有枫香属(Liquidambar)、杨梅属(Myrica)、冬青属(Ilex)、女贞属(Ligustrum)、紫树属(Nyssa)、盐肤木属(Rhus)、黄连木属(Pistacia)等亚热带常见植物类型。研究区不同海拔高度的表土孢粉组合特征基本反映了当地现今的植物构成、植被面貌及其垂直分布规律。结合长江三角洲及其周边地区其他代表性表土花粉资料,首次提出以常绿阔叶木本植物与落叶阔叶木本植物含量之比(E/D),并结合重要优势、标志木本植物科属,初步识别和确立各地带性森林植被的表土花粉指标,为这一地区开展第四纪古植被和古气候等孢粉研究提供参考性依据。     

A Study on the Quantitative Relationship between Pinus Pollen in Surface Sample and Pinus Vegetation

Based on percentages of Pinus pollen in surface samples and that of Pinto vegetation, the data indicates that, in Pinus forest its pollen is more then 90% of total tree pollen, while in non-pine area it is usually less than 30%. The factors influencing dispersal of the Pinus pollen, besides production, are air currents and landform. In the Pinus mixed forest the behavior of associate tree pollen has great effect on statistical result of Pin,ts pollen percentage. To estimate quantitatively the relationship between Pinus plant and its pollen, two curves are fitted by powet regression. Although Pinus pollen has great productivity and complex dispersal characteristics, the relationships between Pinus trees and Pinus pollen shown in our data are relatively consistant.     

Pollen evidence of localized impact on the vegetation of northernmost Finland by hunter-gatherers

Pollen data are presented for the pine forest region around Lake Inari in eastern Finnish Lapland. The region has traditionally been the home of the Saami people who, until the 19th century, followed a seasonally nomadic way of life with an economy based on hunting, fishing and gathering. Although the Saami had no permanent centres of settlement, they did gather together at specific sites every winter, revisiting them year after year over several decades. A pollen diagram is presented from a peat area adjacent to one such winter village, Einehlammet. This shows a clear interference phase characterized by a peak in Ericales followed by a small but distinct peak in Poaceae and the slight, sporadic occurrence of pollen types that can be shown to be connected with human presence. At the same time Pinus values fall and, at the end of the phase, there is a strong increase in Betula pollen. This evidence is compared with that from actually within a dwelling (kota) at another winter village, Nukkumajoki, and is seen to follow exactly the same pattern. Such changes in forest composition in this situation could not be attributed to climatic change. The results demonstrate that, peoples pursuing a purely hunting and gathering economy and moving in the forests in a manner designed to preserve rather than destroy their environment can, nevertheless, cause vegetation changes that are discernable by pollen analysis within a distance of 50 m.     

Tree line identification from pollen data: beyond the limit?

Aim The boreal tree line is a prominent biogeographic feature, the position of which reflects climatic conditions. Pollen is the key sensor used to reconstruct past tree line patterns. Our aims in this study were to investigate pollen–vegetation relationships at the boreal tree line and to assess the success of a modified version of the biomization method that incorporates pollen productivity and dispersal in distinguishing the tree line. Location Northern Canada (307 sites) and Alaska (316 sites). Methods The REVEALS method for estimating regional vegetation composition from pollen data was simplified to provide correction factors to account for differential production and dispersal of pollen among taxa. The REVEALS‐based correction factors were used to adapt the biomization method and applied as a set of experiments to pollen data from lake sediments and moss polsters from the boreal tree line. Proportions of forest and tundra predicted from modern pollen samples along two longitudinal transects were compared with those derived from a vegetation map by: (1) a tally of ‘correct’ versus ‘incorrect’ assignments using vegetation in the relevant map pixels, and (2) a comparison of the shape and position of north–south forest‐cover curves generated from all transect pixels and from pollen data. Possible causes of bias in the misclassifications were assessed. Results Correcting for pollen productivity alone gave fewest misclassifications and the closest estimate of the modern mapped tree line position (Canada, + 300 km; Alaska, + 10 km). In Canada success rates were c. 40–70% and all experiments over‐predicted forest cover. Most corrections improved results over uncorrected biomization; using only lakes improved success rates to c. 80%. In Alaska success rates were 70–80% and classification errors were more evenly distributed; there was little improvement over uncorrected biomization. Main conclusions Corrected biomization should improve broad‐scale reconstructions of spatial patterns in forest/non‐forest vegetation mosaics and across climate‐sensitive ecotones. The Canadian example shows this is particularly the case in regions affected by taxa with extremely high pollen productivity (such as Pinus). Improved representation of actual vegetation distribution is most likely if pollen data from lake sediments are used because the REVEALS algorithm is based on the pollen dynamics of lake‐based systems.     

Effects of landscape structure and climate seasonality on pollen intake by honeybees in Neotropical highland agroecosystems

1. Pollen is the main protein source for honeybee brood and so colony development relies heavily on the availability of pollen in the environment. Intensification of agriculture and climate seasonality are known to alter honeybee pollen intake in temperate regions through changes in resource availability; however, little is known about how honeybees respond to such environmental factors in tropical regions.
2. Pollen collected by honeybees was sampled from apiaries in a Neotropical highland region of Colombia. Pollen species were identified and the effects of landscape diversity, forest area and mean monthly precipitation on the pollen intake by honeybees were evaluated for all pollen species together and pollen species segregated according to forest and anthropic areas.
3. Honeybees were found to be much more associated with anthropic than forest pollen species regardless of landscape structure or precipitation. However, pollen intake from all species and forest species responded positively to landscape diversity and forest area. Precipitation was found not to be related to the overall amount and overall richness of pollen collected by honeybees. Nonetheless, overall pollen diversity was negatively affected by precipitation in less diverse landscapes, whereas anthropic pollen diversity was negatively affected by precipitation in more forested landscapes.

     

Comparison of pollen gene flow among four European beech (Fagus sylvatica L.) populations characterized by different management regimes

The study of the dispersal capability of a species can provide essential information for the management and conservation of its genetic variability. Comparison of gene flow rates among populations characterized by different management and evolutionary histories allows one to decipher the role of factors such as isolation and tree density on gene movements. We used two paternity analysis approaches and different strategies to handle the possible presence of genotyping errors to obtain robust estimates of pollen flow in four European beech (Fagus sylvatica L.) populations from Austria and France. In each country one of the two plots is located in an unmanaged forest; the other plots are managed with a shelterwood system and inside a colonization area (in Austria and France, respectively). The two paternity analysis approaches provided almost identical estimates of gene flow. In general, we found high pollen immigration (~75% of pollen from outside), with the exception of the plot from a highly isolated forest remnant (~50%). In the two unmanaged plots, the average within-population pollen dispersal distances (from 80 to 184 m) were higher than previously estimated for beech. From the comparison between the Austrian managed and unmanaged plots, that are only 500 m apart, we found no evidence that either gene flow or reproductive success distributions were significantly altered by forest management. The investigated phenotypic traits (crown area, height, diameter and flowering phenology) were not significantly related with male reproductive success. Shelterwood seems to have an effect on the distribution of within-population pollen dispersal distances. In the managed plot, pollen dispersal distances were shorter, possibly because adult tree density is three-fold (163 versus 57 trees per hectare) with respect to the unmanaged one.