Pollen types from colonies of Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) established in a coffee plantation

Melipona scutellaris is a eusocial bee with potential to be used as a crop pollinator. This study aimed to identify pollen types used by Melipona scutellaris through the analysis of pollen loads and honey samples in colonies established in a coffee plantation. We analysed 117 pollen loads and pollen content of 15 honey samples. In the pollen loads, we identified 40 pollen types. Poincianella pyramidalis, Coffea arabica, Commelina villosa, Mimosa tenuiflora, Myrcia, Senna macranthera, Solanum and Syagrus coronata stood out as predominant pollen. We found a negative correlation between the abundances of the pollen types Coffea arabica and Mimosa tenuiflora during coffee flowering. In the honey samples, we recorded 33 pollen types. Eucalyptus and Machaerium occurred in frequencies of between 16 and 45%. Although Melipona scutellaris gathers resources from several plant species, its diet is based on a relatively narrow subset of plants.     

Modern pollen samples from alpine vegetation on the Tibetan Plateau

• 1 A set of 316 modern surface pollen samples, sampling all the alpine vegetation types that occur on the Tibetan Plateau, has been compiled and analysed. Between 82 and 92% of the pollen present in these samples is derived from only 28 major taxa. These 28 taxa include examples of both tree (AP) and herb (NAP) pollen types.
• 2 Most of the modern surface pollen samples accurately reflect the composition of the modern vegetation in the sampling region. However, airborne dust‐trap pollen samples do not provide a reliable assessment of the modern vegetation. Dust‐trap samples contain much higher percentages of tree pollen than non‐dust‐trap samples, and many of the taxa present are exotic. In the extremely windy environments of the Tibetan Plateau, contamination of dust‐trap samples by long‐distance transport of exotic pollen is a serious problem.
• 3 The most characteristic vegetation types present on the Tibetan Plateau are alpine meadows, steppe and desert. Non‐arboreal pollen (NAP) therefore dominates the pollen samples in most regions. Percentages of arboreal pollen (AP) are high in samples from the southern and eastern Tibetan Plateau, where alpine forests are an important component of the vegetation. The relative importance of forest and non‐forest vegetation across the Plateau clearly follows climatic gradients: forests occur on the southern and eastern margins of the Plateau, supported by the penetration of moisture‐bearing airmasses associated with the Indian and Pacific summer monsoons; open, treeless vegetation is dominant in the interior and northern margins of the Plateau, far from these moisture sources.
• 4 The different types of non‐forest vegetation are characterized by different modern pollen assemblages. Thus, alpine deserts are characterized by high percentages of Chenopodiaceae and Artemisia, with Ephedra and Nitraria. Alpine meadows are characterized by high percentages of Cyperaceae and Artemisia, with Ranunculaceae and Polygonaceae. Alpine steppe is characterized by high abundances of Artemisia, with Compositae, Cruciferae and Chenopodiaceae. Although Artemisia is a common component of all non‐forest vegetation types on the Tibetan Plateau, the presence of other taxa makes it possible to discriminate between the different vegetation types.
• 5 The good agreement between modern vegetation and modern surface pollen samples across the Tibetan Plateau provides a measure of the reliability of using pollen data to reconstruct past vegetation patterns in non‐forested areas.

     

The role of Mimosa L. (Fabaceae) on pollen provision of Melipona asilvai Moure 1971 in a Caatinga area from Brazil

The pollen spectrum of Melipona asilvai pollen samples, collected over the course of two years, was analysed with the objective of inferring the flora visited by this bee in a region of Caatinga in Bahia, Brazil. This study also evaluated the role of Mimosa species as a source of resources used by Melipona asilvai. Forty-eight pollen types, distributed in 22 families, were morphologically distinguished. The family Fabaceae was notable in the pollen spectrum, with 14 identified types. Mimosa was the most representative and found in all samples analysed, sometimes with high frequency. Mimosa tenuiflora had a 91.5% frequency of occurrence in the sample set and greatly contributed to the monthly samples with percentages over 95% in four of the months analysed. The other Mimosa pollen types identified were M. arenosa, M. quadrivalvis, M. misera and M. pudica. In addition, the Angelonia (Plantaginaceae) type in three samples and the Chamaecrista racemosa (Fabaceae) type in one sample had frequencies over 50% in the pollen spectrum. Other very frequent types in the sample set, occurring in more than 50% of the samples analysed, were the following: Melastomataceae, Solanum paniculatum (Solanaceae), Borreria verticillata (Rubiaceae) and Myrcia (Myrtaceae). Despite the variety of floral sources recorded, it was possible to identify the floral preference of this bee as Mimosa, indicating the importance of Mimosa species as a source of resources used by this bee.     

Melissopalynological analysis of royal jelly from Greece

Microscopic analysis of 82 royal jelly samples obtained from several locations in Greece was carried out in order to study the pollen spectrum of Greek royal jelly. The analysis recorded over 60 taxa. The abundance of each pollen type varied among the areas and the samples. The most frequent pollen types found in the samples were Brassicaceae, Olea europaea, Eucalyptus, Trifolium, Rubus, Carduus-type, Hypericum, Daucus-type and Cistus. The majority of the pollen types found in the royal jelly samples were also found at the pollen flora around the apiaries.     

Floral resources foraged by Geotrigona argentina (Apidae,Meliponini) in the Argentine Dry Chaco forest

This study is the first contribution to knowledge of the relationships between Geotrigona argentina and the plants of the Argentine Dry Chaco forest. A total of 1260 g of honey (corresponding to 146 pots) and 763 g of pollen (63 pots) stored in four underground nests was studied. The honey pots from each nest were homogenised and the four honey samples were analysed by melissopalynological methods, whereas the pollen pots were studied individually. Both classical counts and counts affected by the volume of the pollen types were carried out. Pollen data were statistically analysed. Additional data on both protein and lipid content is also provided. A total of 39 pollen taxa were identified. Pollen collection was focused on a few pollen taxa: Prosopis, Castela coccinea, Maytenus and Capparis; these taxa, together with Ziziphus mistol and Pisonia zapallo, were also important nectar sources. The preliminary results show that pollen collection varied seasonally, being most diverse in the summer when G. argentina incorporates herbaceous plants into its diet. The pollen collection spectrum of G. argentina is similar to that of other Trigonina bees in that the main plant species collected are a few large shrubs or trees, whose flowering consists of small and clustered flowers. Pots with large amounts of monofloral loads with pollen from only a few species suggests an organised foraging behaviour that includes the recruitment of foragers, such as that observed in other eusocial bees.     

Representation of tundra vegetation by pollen in lake sediments of northern Alaska

Aim To understand better the representation of arctic tundra vegetation by pollen data, we analysed pollen assemblages and pollen accumulation rates (PARs) in the surface sediments of lakes. Location Modern sediment samples were collected from seventy‐eight lakes located in the Arctic Foothills and Arctic Coastal Plain regions of northern Alaska. Methods For seventy of the lakes, we analysed pollen and spores in the upper 2 cm of the sediment and calculated the relative abundance of each taxon (pollen percentages). For eleven of the lakes, we used ²¹⁰Pb analysis to determine sediment accumulation rates, and analysed pollen in the upper 10–15 cm of the sediment to estimate modern PARs. Using a detailed land‐cover map of northern Alaska, we assigned each study site to one of five tundra types: moist dwarf‐shrub tussock‐graminoid tundra (DST), moist graminoid prostrate‐shrub tundra (PST) (coastal and inland types), low‐shrub tundra (LST) and wet graminoid tundra (WGT). Results Mapped pollen percentages and multivariate comparison of the pollen data using discriminant analysis show that pollen assemblages vary along the main north–south vegetational and climatic gradients. On the Arctic Coastal Plain where climate is cold and dry, graminoid‐dominated PST and WGT sites were characterized by high percentages of Cyperaceae and Poaceae pollen. In the Arctic Foothills where climate is warmer and wetter, shrub‐dominated DST, PST and LST were characterized by high percentages of Alnus and Betula pollen. Small‐scale variations in tundra vegetation related to edaphic variability are also represented by the pollen data. Discriminant analysis demonstrated that DST sites could be distinguished from foothills PST sites based on their higher percentages of Ericales and Rubus chamaemorus pollen, and coastal PST sites could be distinguished from WGT sites based on their higher percentages of Artemisia. PARs appear to reflect variations in overall vegetation cover, although the small number of samples limits our understanding of these patterns. For coastal sites, PARs were higher for PST than WGT, whereas in the Arctic Foothills, PARs were highest in LST, intermediate in DST, and lowest in PST. Main conclusion Modern pollen data from northern Alaska reflect patterns of tundra vegetation related to both regional‐scale climatic gradients and landscape‐scale edaphic heterogeneity.     

Reliability of pollen ratios for environmental reconstructions on the Tibetan Plateau

Aim Pollen ratios are widely used to gain palaeovegetation and palaeoclimatic information from fossil pollen spectra, although their applicability has seldom been tested with modern pollen data. I used a data set of 113 lake‐surface sediments from the eastern Tibetan Plateau to test the reliability of several pollen ratios. Location The lake‐surface pollen spectra cover a wide range of vegetation types (temperate desert, temperate steppe, alpine desert, alpine steppe, high‐alpine meadow, sub‐alpine shrub, coniferous and mixed forest) and climatic conditions (mean July temperature, T_July: 4.0–17.4°C; mean annual precipitation, P_ann: 104–670 mm). Methods Lake‐surface sediments were analysed palynologically, and several pollen ratios were calculated. These ratios were interpreted with respect to vegetation and climatic conditions. Results The arboreal pollen sum (AP) was highest in samples from forested areas and was significantly correlated with P_ann (r² = 0.44). In non‐forested areas, samples from large lakes and from lakes surrounded by sparse vegetation had increased AP values, suggesting that AP is a useful vegetation density indicator. Artemisia/Chenopodiaceae (A/C) ratios were lowest in desert areas and were positively correlated with P_ann (r² = 0.25). The aridity pollen index was inappropriate for inferring (palaeo‐)climatic information from samples on the eastern Tibetan Plateau as it had no significant correlation with the environmental factors. Artemisia/Cyperaceae (A/Cy) ratios had a significant correlation with T_July (r² = 0.23), but only a weak correlation with P_ann, which indicates that the A/Cy ratio is applicable as a temperature indicator. Furthermore, it is a valuable tool for the differentiation of high‐alpine meadow from steppe vegetation. Main conclusions AP sum, A/C ratio and A/Cy ratio are useful tools for qualitative and semi‐quantitative palaeoenvironmental reconstruction on the Tibetan Plateau; however, the results obtained should not be interpreted quantitatively.     

Floral resources and risk of exposure to pesticides for Melipona quadrifasciata anthidioides Lepeletier 1836 in a Cerrado of São Paulo (Brazil)

Honey and bee bread samples from storage pots of Melipona quadrifasciata anthidioides were collected monthly from April 2015 to May 2016 in the Mogi Guaçu Biological Reserve (22º 10? S, 47º 11? W). The flora in the site is characteristic of the Atlantic Forest with preserved areas of savanna-like vegetation surrounded by commercial forests, orchards and various crops of exotic and native plants. Samples were analysed with the use of melissopalynological methodology and 46 pollen types from 38 genera and 30 families were identified in 25 honey samples. Fabaceae, Asteraceae, Myrtaceae, Sapindaceae showed the greatest pollen richness in honey. Predominant nectariferous pollen types were Anadenanthera, Cordia, Eucalyptus, Mimosa scabrella, Schefflera, Sida, Serjania and Vernonia. Twenty-eight types of pollen from 21 genera and 19 families were identified in 22 bee bread samples. Fabaceae, Asteraceae and Myrtaceae showed the highest pollen richness. Anadenanthera, Cecropia, Eucalyptus, Melastomataceae, Mimosa scabrella, Mimosa verrucosa and Myrcia were the most frequent polliniferous pollen types. Principal component analysis (PCA) demonstrated that honey and pollen samples formed two main groups of similarity, mainly due to Eucalyptus’ nectar and pollen of Melastomataceae, respectively. Melipona quadrifasciata anthidioides collected nectar and pollen from the preserved areas as well as in the secondary and ‘ruderal’ vegetation and in cultivated forests/fields, suggesting their importance as pollinators both of native flora and exotic species. The use of trophic resources of plants grown with pesticides is a concern for the conservation of these species of bee and should be better studied.     

A modern pollen–climate calibration set from northern Europe: developing and testing a tool for palaeoclimatological reconstructions

Aims and location The potential of pollen records in quantitative climate reconstructions has been widely debated but seldom tested. Our aim is to develop a pollen–climate transfer function for northern Europe and test its performance and inference power by numerical cross‐validation with modern climate data. Annual mean temperature (T_ann) was assessed as the critical climatic variable because T_ann has a distinct south–north gradient (5.5 to ?4.7 °C) in the study region with a corresponding zonal vegetation gradient from the hemiboreal zone in the south to the northern boreal zone in the north. Methods We collected 137 pollen surface samples from small‐ to medium size lakes from southern Estonia to northern Finland. The transfer function for T_ann was developed with weighted averaging partial least squares (WA‐PLS) regression. All 102 terrestrial pollen and spore types were included in the calculation sum and all 137 surface samples and all 102 taxa were included in the transfer function. The performance of the WA‐PLS transfer function was evaluated by leave‐one‐out cross‐validation. Results A cross‐validated root mean square error of prediction (RMSEP) of our model is 0.89 °C and the coefficient of determination (r²) between the observed meteorological T_ann values and those predicted by the model in leave‐one‐out cross‐validation is 0.88. The RMSEP as a percentage of the gradient length of T_ann is 8.8%. These figures indicate high performance statistics for our transfer function compared with other inference models. This is probably because of standardization of our surface‐sampling and pollen‐analytical procedures, careful selection of the surface sample sites with consideration of the relevant pollen source area, the simple patterns of vegetation zones and climate in the study area, and the mostly natural floristic composition of the forests in northern Europe. However, we also demonstrate the limitations of our model in reliably detecting fine‐scale climatic variability. Main conclusions The study shows the strong influence of T_ann on modern pollen composition and demonstrates the potential of pollen data for long‐term climate reconstructions in northern Europe. It also provides evidence against simple interpretations of fine‐scale variations in a single climate reconstruction. In particular, our results highlight the importance of careful study design and implementation in the construction of pollen–climate transfer functions.     

Floral Pollen Bioactive Properties and Their Synergy in Honeybee Pollen

Honeybee pollen (HBP) is a mixture of floral pollen collected by honeybees near the hive. It is characterized by a composition rich in phenolic compounds, carotenoids and vitamins that act as free radicals scavengers, conferring antioxidant and antibacterial capacity to the matrix. These bioactive properties are related to the botanical origin of the honeybee pollen. Honeybee pollen samples were collected from different geographical locations in central Chile, and their total carotenoid content, polyphenols profile by HPLC/MS/MS, DPPH radical scavenging capacity, and antimicrobial capacity against S. pyogenes, E. coli, S. aureus, and P. auriginosa strains were evaluated. Our results showed a good carotenoids content and polyphenols composition, while antioxidant capacity presented values between 0–95 % for the scavenging effect related to the botanical origin of the samples. Inhibition diameter for the different strains presented less variability among the samples, Furthermore, binary mixtures representing the two most abundant species in each HBP were prepared to assess the synergy effect of the floral pollen (FP) present in the samples. Data shows an antagonist effect was observed when assessing the carotenoid content, and a synergy effect often presents for antimicrobial and antioxidant capacity for bee pollen samples. The bioactive capacities of the honeybee pollen and their synergy effect could apply to develop new functional ingredients for the food industry.     

Analysis of protein content in pollen loads produced in north-west Spain

An analysis was made of the protein content of pollen loads produced by the bees in a hive situated in Viana do Bolo (Ourense, north-west Spain), to establish whether or not the relative quantity of protein in the pollen of each plant species influences the preference made by the bee of the flowers that supply pollen to the hive. This analysis was performed on all types of pollen that formed more than 5% of the pollen spectrum. Pollen load samples were collected directly from the hive from March to September. Pollen loads were separated by colour, and their specific homogeneity was confirmed microscopically. The Bradford method has been used for protein extraction and spectrophotometry was used for the determination of protein content. The results show that the different pollen loads have high protein content. Pollen of the plant species that reached relatively higher percentages in the pollen spectrum are also those that have the highest protein content. These were Cytisus scoparius type, uncultivated Poaceae, Quercus robur type, Sanguisorba minor, Salix fragilis and Spergularia rubra type. The pollen of the systematic units, which had pollen loads that could be identified at the level of species, maintained a constant value of protein content independently of the date the samples were obtained. The pollen of the systematic units, which had pollen loads that could be identified at the level of pollen type, has varied in protein content in the analyses performed on samples obtained on different dates. This result is due to the fact that the different species that integrate the pollen type flower on different dates, and thus have a pollenkitt with different characteristics.     

Modern vegetation–pollen–climate relationships for the Pampa grasslands of Argentina

Aim To analyse the relationships between potential natural vegetation, pollen and climate in order to improve the interpretation of fossil pollen records and provide the background for future quantitative palaeoclimatic reconstructions. Location Pampa grasslands of Argentina, between 33–41° S and 56–67° W. Methods Modern pollen data were obtained from a pollen data base developed by the Grupo de Investigación de Paleoecología y Palinología, Universidad Nacional de Mar del Plata, Argentina (143 surface samples and 17 pollen types). Analysis of pollen and climate data involved multivariate statistics (cluster analysis and principal components analysis), scatter diagrams, Pearson’s correlation and isopoll mapping. Results Vegetation patterns at regional scales (grasslands and xerophytic woodlands) and local scales (edaphic communities) were identified by cluster analysis of pollen surface samples. The main climatic variables that appear to constrain the vegetation distribution and abundance of taxa are mean annual precipitation, annual effective precipitation and summer temperature. Individual pollen types such as Chenopodiaceae, Apiaceae, Cyperaceae, Prosopis, Schinus, Condalia microphylla and other xerophytic taxa are good indicators of moisture regime. Many pollen types are significantly correlated with summer temperature. The modern vegetation–pollen–climate relationships vary in a broadly predictable manner, supporting the contention that fossil pollen assemblages can be related to particular climatic characteristics. Main conclusions An expanded suite of modern analogues facilitated new insights into vegetation–pollen–climate relationships at the regional scale in Pampa grasslands. Relationships between individual pollen types and climate are appraised at a regional scale and new modern analogues are presented. The results provide the basis for improved vegetation and climate reconstruction from fossil records of the study area.     

Modern pollen–vegetation relationships along transects on the Whangapoua Estuary, Great Barrier Island, northern New Zealand

Aims To quantify pollen–vegetation relationships from saline to freshwater in an estuarine gradient from surface samples of the modern pollen rain, to allow more accurate interpretations of the stratigraphic palynological record. Location Whangapoua Estuary, Great Barrier Island, northern New Zealand. Methods Six transects were laid out along a vegetation sequence running from estuarine mud to freshwater swamp. Along these transect lines, 108 plots were sampled for vegetation and surface sediments from wet sand, mud, plant litter or moss (sand and mud sites are inundated by most tides, other sites less frequently). All sediment samples were analysed for pollen. The relationships between plant species frequency and pollen representation were examined at a community scale using twinspan and ordination analyses, and for individual species using fidelity and dispersibility indices, regression and box‐plot analyses. Results The quantitative relationships between source taxon vegetation frequency and its pollen representation varied between species due to differential pollen production and dispersal. twinspan of the surface pollen samples suggests five vegetation types: (A) mangrove (Avicennia marina); (C) Leptocarpus similis salt meadow; (D) Baumea sedges; (E) Leptospermum shrubland; and (F) Typha/Cordyline swamp forest. The (B) Juncus kraussii community is not represented palynologically owing to the destruction of its delicate pollen grains during acetolysis of samples. Detrended correspondence analysis places these communities on an estuarine‐to‐freshwater gradient. However, pollen assemblages at the seaward end of the salinity gradient are less clearly representative of the associated vegetation than those at the landward end, probably because the open vegetation at the former allows the influx of wind‐ and water‐dispersed pollen from surrounding vegetation. Main conclusions The vegetation pattern (zonation) at Whangapoua is reflected in the pollen rain. When the long‐distance and over‐represented pollen types are excluded, five out of six of the broad vegetation communities can be identified by their pollen spectra. Species with high fidelity and low‐to‐moderate dispersibility indices can be used to identify the vegetation types in the sedimentary sequences. The more open vegetation types at the ‘marine end’ of the sequence tend to be ‘overwhelmed’ by regional pollen, but the nature of the sediments and the presence of discriminatory species (e.g. A. marina, Plagianthus divaricatus, Cordyline australis), even in small amounts, will allow correct identification of the local vegetation represented in sedimentary palynological sequences. A box‐plot analysis indicates that the pollen and spore types A. marina (mangroves), Sarcocornia quinqueflora (salt meadow), P. divaricatus (sedges), Gleichenia (shrubland) and C. australis (swamp forest) are highly discriminatory in relation to vegetation type. These discriminatory palynomorphs help with the interpretation of stratigraphic pollen studies. However, salt marsh vegetation communities in the sediments must be interpreted with caution as the marine sediments are easily affected by erosion, bioturbation and tidal inundation effects.     

Pollen analysis of honeys of Melipona (Michmelia) seminigra merrillae and Melipona (Melikerria) interrupta (Hymenoptera: Apidae) bred in Central Amazon,Brazil

The pollen present in honey in colonies of Melipona seminigra merrillae and Melipona interrupta bred in Manaus was analysed. Between August and October 2012, honey samples were collected from the Sucupira meliponary, located in Manaus, Amazonas, Brazil. We identified a total of 70 pollen types belonging to 35 botanical families. In the samples from Melipona seminigra merrillae, the most represented pollen types were: Miconia-type (Melastomataceae) was the dominant pollen (DP) in August (51.19%), September (76.83%) and October (58.33%); Triplaris-type (Polygonaceae) was an accessory pollen (AP) in August (20.5%); and the remaining pollen types were classified as isolated pollen (IP), with Talisia macrophylla (Sapindaceae) exhibiting the highest percentage in August (12.92%). For Melipona interrupta, the most frequent pollen types were as follows: Miconia-type was the DP in August (59.33%) and October (61.33%) and an AP in September (37.5%); and Triplaris-type was an AP in August (35.83%), September (34.16%) and October (23.33%). The diversity of pollen types was not significantly different between the bees in the months evaluated. However, there was a large significant niche overlap in the months studied, August (O_ik = 0.95), October (O_ik = 0.89) and September (O_ik = 0.69), revealing that of the 70 pollen types found in the samples, 22 were shared by the two bee species in large proportions, 28 were exploited exclusively by Melipona seminigra merrillae and 20 were collected only by Melipona interrupta.     

6. Peat-bog Begbunar (Osogovo Mountains,south-west Bulgaria): Four millennia of vegetation history

The aim of this study was to estimate the polleniferous potential of the most common plant communities and crops across the landscape through the study of pollen loads collected by Apis mellifera. We analysed pollen load samples from hives located in Mallorca (western Mediterranean) for one year and compared the results with a phytosociological study of the foraging area. We also analysed meteorological data to evaluate the influence of some environmental factors on the pollen production phenology. We identified 74 different pollen types (66.2% from native flora, 25.7% from exotic flora, and 8.1% from crops) belonging to 33 families. The highest polleniferous potentials in the landscape were attained by sclerophyllous forests (Quercetea ilicis) in spring, crops in autumn, wild annual rangelands (Stellarietea mediae) in winter and gardens in late summer. Our results suggest that the higher the coverage present in a vegetation class, the higher the quantity and diversity of pollen that may be provided to pollinators; therefore, its polleniferous potential may be higher. Some meteorological conditions (rainfall, temperature and daily hours of sunlight) may affect this potential through their influence on flowering phenology.     

Arecaceae potential for production of monofloral bee pollen

Bees often collect pollen from plants that are near their colonies or apiaries. Arecaceae are characterised by having species that flower throughout the year and produce large quantities of pollen. Pollen grains of Arecaceae have two main forms, namely monosulcate and trichotomosulcate. The study area is located in the coastal region of the state of Sergipe, Brazil, where large amounts of bee pollen are produced by Apis mellifera. This study aims to evaluate how Arecaceae contribute to the production of monofloral bee pollen. Samples of bee pollen loads were collected each month for two years (totalling 24 samples), acetolysed, and mounted on permanent slides. At least 500 grains of pollen were counted for each sample, the data was analysed, and figures were made using the Tilia software. The pollen grains of Cocos nucifera were present in 23 samples (96%), and concentrations of this pollen type varied between 1.1 and 46.8% (but were commonly above 20%). The concentration of Arecaceae pollen grains is the result of the large-scale production of coconuts along the coastline. However, the presence of other pollen types, such as Mimosa arenosa, Mimosa pudica, Mikania and Myrcia, compliments the diets of bees in the region. The results show that even when in low frequency, Cocos nucifera pollen grains represent a large proportion of pollen content compared with other pollen types, because of the large size of Arecaceae pollen grains.     

Palynological differences in the pollen content of Eucalyptus honey from Australia,Portugal and Spain

A melissopalynological study was carried out on 75 samples of Eucalyptus honey from different countries (22 from Australia, 13 from Portugal and 40 from Northwest Spain), in which a total of 145 different pollen types were identified. Of such, only Eucalyptus, Acacia, Brassica, Echium, Ligustrum, Plantago, Rumex, Taraxacum, Trifolium and Vicia pollen are present in the honeys from all three countries.

Among the most abundant pollen types in Australian honeys, those belonging to the following families stand out: Myrtaceae (Angophora and Melaleuca), Fabaceae, Asteraceae, Proteaceae and Euphorbiaceae, along with Raphanus, Echium and Citrus.

In the Portuguese honeys, the presence of Fabaceae, Rosaceae and Cistaceae stands out, with Castanea and Erica as secondary pollen types, while Fabaceae, Asteraceae, Boraginaceae, Cistaceae and Scrophulariaceae are the families with the highest quantity of pollen types in the samples from Spain. In the latter, the most important secondary pollen types are: Castanea, Cytisus, Erica, Lotus, Salix and Rubus.     

Modern pollen/vegetation/land-use relationships in mountain environments: an example from the Champsaur valley (French Alps)

This study aims at elucidating modern pollen spectra/environmental data relationships from both natural and human-induced vegetation types as an aid for palaeo-ecological reconstructions. A set of 51 surface moss polsters was sampled from different vegetation and land-use types in the Champsaur area (French Alps) and analysed to obtain modern pollen analogues of ancient cultural landscapes in mountain ecosystems. Samples were selected from grazed areas, mown meadows, cultivated fields, fallow land and deciduous and coniferous forests. Vegetation composition around the sampling points and seventeen types of environmental variables (e.g., management type, soil and topography) were collected all for these 51 sites. Patterns of modern local pollen variation in relation to the environmental variables were explored by means of canonical correspondence analysis (CCA) and associated statistical tests. This correlative model allows us to determine the major explanatory variables and to identify taxa indicative of particular anthropogenic activities, and thus may help to calibrate fossil pollen assemblages.The indicator pollen types are evaluated in the light of comparable material from lowland and mid-elevation areas of western Europe. The results of the French data-set confirm some of the conclusions drawn from the North European data-sets, but also show some site specific features. Pollen markers with a broader global significance common to other regions include Rhinanthus type, Apiaceae and Dipsacaceae for mown meadows, Urtica type, Plantago media/major, Trifolium type and Potentilla type for grazed areas, and Cerealia type, Centaurea cyanus, and Polygonum aviculare for cultivated fields. New pollen anthropogenic indicators typical of our study area are Sanguisorba officinalis, Vicia type (mowing), Lotus type, Onobrychis type, Centaurea nigra type, Serratula type (grazing), Sinapis type and Papaver rhoeas (cultivation). This study provides potentially valuable analogues for human-induced vegetation types, and it may then become possible to interpret more objectively local pollen diagrams from Alpine mountain environments in terms of past cultural landscape development.     

A study of variation in the pollen spectra of honeys sampled from the Baixa Limia‐Serra do Xurés Nature Reserve in north‐west Spain

The pollen content of eleven honey samples from ten different apiaries in the Baixa Limia – Serra do Xurés Nature Reserve and other honey commercialised by the cooperative as “Mel do Xurés” (north‐west Spain) was subjected to quantitative and qualitative melissopalynological analysis. The quantitative analysis found that ten samples belonged to Maurizio's Class III and one to Class IV. According to the qualitative analysis, four samples were classified as unifloral honey with Erica, four samples as multifloral honey with Erica pollen as the principal component and three samples as multifloral honey with Cytisus‐type pollen and Erica as the principal component pollen. The pollen spectra differ between the diverse honeys analysed, with a common denominator being Erica and Cytisus‐type pollen being abundant in all. For the rest of the samples, the pollen spectra were mainly the same, but with different relative percentages among secondary elements. Thus, either as a secondary or an important element, 91% of the honeys contained Quercus, 82% Castanea sativa Miller, 45% Rubus, 36% Cistus and 27% Lithodora prostrate (Loisel) Griseb,. In particular, we record for the first time the presence of Ribes and Ilex aquifolium L. pollen in Spanish honeys as an important minor or minor pollen component.     

Pollen analysis of Apis dorsata Fabricius honeys in Bankura and Paschim Medinipur districts,West Bengal

One-hundred-and-five species corresponding to 38 families were identified through pollen analyses of 53 Apis dorsata honeys collected from Bankura and Paschim Medinipur districts, West Bengal. The families most frequently encountered were Fabaceae, Arecaceae, Asteraceae and Myrtaceae. Fabaceae had the greatest representation in number of pollen types (18 types), followed by Asteraceae (nine types), Cucurbitaceae (seven types), Lamiaceae and Myrtaceae (each with six types) and Malvaceae and Rutaceae (each with five types). Most of the honey samples correspond to class I. The presence of dominant pollen was detected in 18 samples. The predominant pollen types were Borassus flabellifer, Sesamum indicum (during summer), Eucalyptus globulus (during late autumn), Brassica nigra, Eucalyptus globulus (during winter) and Borassus flabellifer and Lannea coromandelica (during spring). The unifloral honeys obtained mostly during late autumn and winter were dominated by Eucalyptus globulus type. In monsoon and autumn unifloral honeys containing predominant pollen types (> 45%) were not found. However, according to frequency distribution the pollen types represented as very frequent were Peltophorum pterocarpum, Tridax procumbens (in monsoon) and Acacia auriculiformis, Cocos nucifera, Eucalyptus globulus, Tridax procumbens and Ziziphus mauritiana (in autumn). The seasonal diversity of pollen types obtained was at a maximum during spring (36 types) and minimum during late autumn (14 types). Seasonal variation in the number of pollen types per sample range from 5.86 ± 1.87 (during late autumn) to 6.86 ± 1.95 (during autumn) and exhibit low correlation (r = 0.31) with floral diversity. The diversity of pollen types per unifloral honey sample remains lower than multifloral honeys.