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Understanding how multi‐scale environmental heterogeneity shapes the structure and functions of animal and plant communities is pivotal in agroecology. Our capacity to ensure the provision of ecosystem services (ES), the sustainability of agroecosystems and the efficiency of agri‐environmental schemes (AES) relies on this knowledge. There is growing interest in how biodiversity and ES are affected by the interplay between landscape characteristics and agricultural management (e.g., intermediate landscape complexity hypothesis; ILCH). However, studies have typically focused on classical measures of community structure (e.g., species abundance, richness and biodiversity), tending to neglect the effects on the structure and stability of ecological networks and the increased risk of biotic homogenization (i.e., loss of β‐diversity). In this work, we use bee trap nests to sample pollen–solitary bee mutualistic networks in 9 pairs of olive groves under different management regimes (conventional vs. organic) in a landscape complexity gradient in southern Spain. We analyse the mutualistic networks at farm level to test the ILCH and study how agricultural practices and landscape complexity interact to affect the properties of these networks. We also explore the effects on spatial biotic homogenization by performing multivariate analyses of the composition and abundance of bee–plant communities and their pairwise interactions. The results show that solitary bee–plant networks have greater complexity and stability on organic olive farms embedded in relatively heterogeneous landscapes. Differences from conventional management were higher in landscapes of intermediate complexity but were non‐significant on olive farms located in simpler landscapes. β‐diversity of bees, plants and their pairwise interactions was also greater on organic olive farms. In conclusion, human‐induced environmental heterogeneity interacts at different scales to shape plant–solitary bee networks in olive groves, which may have important implications for ES provision and the effectiveness of agri‐environmental measures. A free Plain Language Summary can be found within the Supporting Information of this article.

In the present study, bio-meteorological regression models for forecasting the fruit produced by the olive trees in Jaen (southern Spain), the province with the largest extension of olive groves in the world, were revised and improved. The new forecasting models were constructed using partial least-squares regression, taking the annual olive yield as the dependent variable and several aerobiological and meteorological parameters as the independent variables. The models were validated following a full cross-validation method. A 23-year period (1994–2016) was used. The number of days with pollen concentrations ≥400 pollen grains m−3 was revealed as a newfangled predictive variable to accurately predict the olive harvest in this area, being included in the forecasting model with the highest determination coefficient value (R2 = 0.89). Weather-related variables such as the cumulative precipitation from October to December of the previous year or the mean maximum temperature from January to March were also factors of particular importance on crop production. The new model proposed provides early and effective olive crop forecasting by using independent variables which can be easily obtained towards the middle of June, also incorporating to the model the phenological variability associated with changes in the local weather. The approach shown in this study readily could be applied to any potential new situation and to be extensible to other similar olive growing areas across the Mediterranean region.

Over the last few decades, global warming is prompting phenological changes in numerous plant species across Europe, and a trend towards rising airborne pollen concentrations has been detected. This study, focused on the most frequent pollen types from arboreal and herbaceous species in the airborne spectrum of Jaen (southern Spain), revealed significant changes in airborne pollen intensity and duration of the pollen season over the 23-year study period. Here Cupressaceae, Olea, Pinus, Platanus, Quercus as arboreal taxa and Plantago as herbaceous taxa were the most important with notable changes of at least three pollen season characteristics. Airborne pollen trends from arboreal taxa with high to very high allergenic potential are rising in line with the local temperature increasing trend, and their pollen seasons tend to end later and last longer. However, both the pollen concentrations and the duration of the pollen season of some herbaceous taxa are declining. The climate conditions projected for south Europe under different greenhouse emissions scenarios could continue to prompt greater pollen release and longer pollen season in tree species, especially those that flowering in winter and early spring, but these warming trends might be adverse for the local development of some herbaceous species and favorable for others sharing the same ecological niche. If similar warming trends accompany long-term climate change, greater exposure times to seasonal allergens may occur with subsequent effects on health.

The germination of five species of annual native leguminous plants ( Astragalus hamosus L., Medicago minima (L.) L., Medicago orbicularis (L.) Bartal, Medicago polymorpha L., and Scorpiurus muricatus L.), present spontaneously in the ground cover of olive groves, was tested under experimental garden conditions using different scarification and planting depth treatments. Surface and deep planting were carried out after submitting seeds to different treatments: mechanical scarification (MS) with sandpaper, chemical scarification consisting of immersion in sulphuric acid for five (S_5) or ten (S_10) minutes and non-scarified seeds (Con). Germination success was calculated by analysing (i) the final germination and (ii) the pattern of germination that occurred during the 27 months that the study lasted. The most effective method for interrupting the dormancy of all the species (except M. polymorpha ) was surface seeding with MS. Unlike the other treatments, in which there were germination peaks in each successive autumn, manually scarified seeds only germinated in the first autumn after sowing, and only within 10 days in the case of surface planting and within 20 days in deep-sown seeds. The speed and abundant germination obtained after manual scarification indicates that the dormancy of the tested species is a product of the hardseededness of the seed coat. Chemical scarification only managed to break down the tough seed cover in the case of deep-sown M. orbicularis .

a b s t r a c t The aim of the present study was to analyse long temporal trends in cumulative temperatures and olive (Olea europaea L.) reproductive features, including full flowering dates and daily pollen concentrations, in three Mediterranean areas. The study used a 19-year database (1993-2011) of pollen and temperature records from the sites of Perugia (Italy), Jaen (Spain) and Zarzis (Tunisia). The analysis of long-term trends in both temperatures and olive reproductive cycles was performed using two approaches. The first is a seasonal trend decomposition procedure based on locally weighted regression (Loess) smoothing (STL), which is a filtering procedure for decomposing seasonal time series into three components: trend, seasonal, and remainder. The second approach analyses the trend components using Mann-Kendall tests. Loess smoothing provides a good approach to study long-term meteorological and phenological trends. Removing both the seasonal and the remainder components, the real rising trends over time can be interpreted. In general, a significant and clear increasing trend in the spring cumulative temperature was revealed, with decreasing trends in the full flowering dates of the olive trees located in Perugia and Zarzis. Moreover, olive pollen emissions are decreasing, which is more evident for the highest and lowest latitudinal study sites. These data indicate that increasing temperatures result in both anticipation of olive tree flowering and lower airborne pollen emission. As a consequence, the lower atmospheric pollen levels will reduce human exposure to olive pollen in the Mediterranean area. These patterns are evident for the highest and lowest latitudes, but not clear in the intermediate latitudes of Jaen, where further analysis is needed.

The aim of this study was the elaboration and the spatio-temporal interpretation of Olea europaea L. airborne-pollen maps across the main olive cultivation areas within the Mediterranean basin (i.e. Tunisia, Spain, Italy). The study was performed using aerobiological databases recorded from 27 georeferenced study sites. Maps were elaborated for different 10-day period through spring and summer: 1, 10, 20, 30 April; 10, 20, 30 May; 9, 19, 30 June; and 10 July. Average pollen counts in each study site were considered for the 13-year period from 1999 to 2011. Both these 10-day period of pollen emission data and the geographical coordinates were used as variables in the elaboration of the 10-day period maps. The ‘Natural Neighbour’ interpolation method was used. The statistical relationship between spatial location and maximum pollen emission was studied using linear regression and cluster analyses. The airborne-pollen maps show a spatio-temporal pattern in the pollen season. The maximum pollen emission is progressively delayed with northward changes in latitude, and the classification of the Olea maximum pollen emission date into four latitudinal categories is defined. The maximum Olea pollen concentrations were mainly recorded around 20 May. Early flowering in Tunisia coastal zones can indicate the onset of the olive pollen release season in the occidental Mediterranean region, while the central olive-growing areas in Italy can indicate the end of the olive pollen release season. These maps give information of the major risk days to the people who are allergic to olive pollen.

This study analysed the germination success of pods of six annual native legumes species: Astragalus hamosus, Medicago minima, Medicago orbicularis, Medicago polymorpha, Medicago rigidula and Scorpiurus muricatus. The use of these species has been proposed as a means of generating and improving herbaceous cover in olive groves. Germination success was studied in terms of the variability in the number of seeds germinated per pod after 18 months at two different sowing depths, on the surface (S) and buried 10 mm (B). Pods were subject to five different pre-germination treatments: chemical scarification, consisting of immersion in sulphuric acid for 15 min (S_15) and 20 min (S_20), immersion in water for 48 h (W_48), pod precooled to -18ºC for one month (P_18º) and untreated pods (Con). The results showed that the effectiveness of the different treatments and sowing depths depended on the species, and that there were no problems of ‘sibling-competition’ in any of the treatments or at any of the sowing depths. Species with larger, non-spiralled pods, such as A. hamosus or S. muricatus, or with very loosely spiralled pods such as M. orbicularis, had greater germination rates when buried, mainly in the case of untreated pods and pods that were immersed in sulphuric acid for 20 minutes.

In some areas, forests are being affected in diverse aspects such as structure, composition and biodiversity showing an increase or a decrease in the growth rates. Pinus is one of the most dominant genera in the forests of the Northern Hemisphere. This study analyzes the pine pollination patterns in 30 locations of Spain with an average of 21-year dataset. The aim is to evaluate possible changes in flowering intensity as well as in annual pollen production trends, according to the airborne pollen patterns. Annual Pollen Indices show three threshold values: (1) over 4000 grains per year in Catalonia, the Central System Mountains and Ourense (Galicia), (2) between 4000 and 1000 grains in central-south Spain and in the Balearic Islands, and (3) under 1000 in eastern Spain, Cartagena and the Canary Islands. Airborne pollen patterns were also influenced by Pinus species: The species located in the littoral and low land areas pollinated in the first pollination phase, from February to April, and the mountain pine species did in the second one, from April to June. The statistical analyses reveal increasing significant trends in 12 sites and significant decreasing trends in two. The Pinus flowering intensity is showing an earlier start and a delay in the end of the pollination period, thus a longer period of pollen in the air. This study suggests that the aerobiological monitoring is an interesting bio-indicator of changes happening in Pinus landscapes, and therefore explains the vulnerability of this genus in Spain. COST ES0603 EUPOL; Laboratorios LETI S.A.; Proyecto EOLO-PAT; European Commission for “ENV4-CT98-0755”; Spanish Ministry of Science and Technology I+D+I for “CGL2009-11205,” “CGL2012-39523-C02-01/CLI,” “MTM2015 67802-P,” “FENOMED CGL2014-54731-R,” and FEDER “A way to build Europe,” and CONSOLIDER CSD 2007_00067 GRACCIE; also the Andalusian Government for “P10-RNM-5958,” the Extremadura Government for “PRI BS10008,” the Catalan Government AGAUR for “2009SGR1102” and “2014SGR1274” and the Health Department of the Castilla y León Government, RACYL. This work is contributing to the ICTA “Unit of Excellence” (MinECo, MDM2015-0552). 1.515 JCR (2017) Q3, 49/85 Biology, 153/241 Environmental Sciences UEC

In the present study, bio-meteorological models for predicting olive-crop production in the southern Iberian Peninsula were developed. These covered a 16-year period: 1994-2009. The forecasting models were constructed using the partial least-squares regression method, taking the annual olive yield as the dependent variable, and both aerobiological and meteorological parameters as the independent variables. Two regression models were built for the prediction of crop production prior to the final harvest at two different times of the year: July and November. The percentage variance explained by the models was between 83% and 93%. Through these forecasting models, the main factors that influence olive-crop yield were identified. Pollen index and accumulated precipitation, especially as rain recorded during the pre-flowering months, were the most important parameters for providing an explanation of fluctuations in fruit production. The temperature recorded during the two months preceding budburst was another important variable, which showed positive effects on the final yield. The July model that provides accurate predictions of fruit production eight months prior to the final harvest is proposed as an optimal model to forecast fruit produced by olive trees in western Mediterranean areas.

The Multiple Use Natural Reserve of Monterrico lies on the Pacific coast of the southwest Guatemala in the Chiapas Sector of the Chiapaneca-Hondurena Province. It belongs to the Guatemalan System of Protected Areas and has a predominantly estuarine and coastal marine ecosystem. We took 218 vegetation releves that contained 72 species belonging to 138 genera and 69 plant families. Multivariate analysis techniques have led to the determination of seven different associations. Three of them are mangrove swamp associations (Lagunculario-Rhizophoretum manglis; Lagunculario-Avicennietum germinantis Peinado, Alcaraz, Delgadillo, De la Cruz, Alvarez and Aguirre, 1994; Rhizophoretum manglis Cuatrecasas, 1958). Three new associations are proposed. These are one reed–bulrush association (Typho domingensis-Phragmitetum australisass. nova) and two sand-dwelling associations, one made up of evergreen grasses dominated by Canavalia rosea which grows on mobile dunes (Thephrosio-Canavalietum roseaeass. nova) and a dry for...

The aim of this study was to evaluate the viability and longevity of the pollen grains of the olive cultivar ‘Picual’, the most extensive and important olive cultivar in the Iberian Peninsula. Over a 3-year period (2007–2009), viability of the pollen grains of 15 ‘Picual’ cultivar trees was measured using the Fluorochromatic Reaction (FCR). These olive trees were distributed along different altitudinal areas of the province of Jaen (southeast Iberian Peninsula). The percentages of viability did not show any geographical variability. In general, the percentage of viability did not vary from one year to another. With an average value of 49%, the viability of the pollen in the cultivar ‘Picual’ could be classified as medium-range. ‘Picual’ pollen grains have the highest viability after 24 hours of anther dehiscence. Viability declines rapidly with time. The longevity of the pollen grains was about seven days. The first three days after anthesis are the most important for fertilisation. A rapid decline in pollen viability may considerably reduce effective fertilisation and could negatively influence fruit production. For this reason, these findings should be considered for the improvement of olive fruit yields.

The possible impact of altitude and the related microclimatic conditions on the total production of fruiting branches, inflorescences, flowers and pollen grains of olive trees Olea europaea was analysed. A total of 90 Picual cultivar trees, the most extensive olive cultivar in the Iberian Peninsula, were studied for a three-year period (2007–2009). The study shows that production of flowers and pollen grains in a cultivar of the olive tree varies according to the microclimate. Our study also indicates that the olive trees frequently can have up to half a million flowers per tree. Moreover, the total flower production differs between years and study areas. In the Picual cultivar, the average production of pollen grains per anther is usually more than 60 000 grains. The total production of pollen per tree is around 72 000 million on average. The most favourable microclimatic conditions for reproduction in olive trees are found in years and olive growing areas with low temperature and high precipita...

The survey deals with juniper groves of Juniperus oxycedrus, i. e. the edaphoxerophilous communities dominated by J. oxycedrus subsp. oxycedrus and J. oxycedrus subsp. lagunae in the centre and south of the Iberian Peninsula. The study of the vegetation has been carried out using the phytosociological method, complemented by a multivariate analysis to statistically process both bibliographical and field releves. As a result, a new phytosociological alliance (Juniperion oxycedro-lagunae) encompassing four new associations (Pistacio terebinthi—Juniperetum lagunae, Stipo tenacissimae—Juniperetum lagunae, Echinosparto iberici—Juniperetum lagunae and Cytiso eriocarpi—Juniperetum lagunae) and the community of Phlomis purpurea and J. oxycedrus subsp. lagunae is proposed. These juniper groves are plant formations of general interest for the European Union and exhibit interesting endemic flora and vegetation.

Airborne pollen monitoring is an effective tool for studying the reproductive phenology of anemophilous plants, an important bioindicator of plant behavior. Recent decades have revealed a trend towards rising airborne pollen concentrations in Europe, attributing these trends to an increase in anthropogenic CO2 emissions and temperature. However, the lack of water availability in southern Europe may prompt a trend towards lower flowering intensity, especially in herbaceous plants. Here we show variations in flowering intensity by analyzing the Annual Pollen Index (API) of 12 anemophilous taxa across 12 locations in the Iberian Peninsula, over the last two decades, and detecting the influence of the North Atlantic Oscillation (NAO). Results revealed differences in the distribution and flowering intensity of anemophilous species. A negative correlation was observed between airborne pollen concentrations and winter averages of the NAO index. This study confirms that changes in rainfall in the Mediterranean region, attributed to climate change, have an important impact on the phenology of plants.

This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories., Este trabalho apresenta um estudo florístico e fitossociológico das comunidades de florestas secas da República Dominicana. Um total de 69 amostras foram obtidas pelo método relevé em biótopos florestais secos. As amostras foram posteriormente submetidas à análise de correspondência destendenciada para a determinação e estudo de possíveis agrupamentos. O estudo não abrange formações arbóreas desenvolvidas sobre serpentinitos, nem as chamadas florestas semideciduais, peculiares às áreas de maior pluviosidade. Foram identificados nove fitocenoses. Os resultados mais significativos levaram à descrição de seis novas associações fitossociológicas: Simaroubetum berteroani (floresta espinhosa seca em dunas costeiras), Phyllostylo rhamnoidis-Prosopidetum juliflorae (floresta seca perturbada do sul da República Dominicana), Consoleo moniliformis-Camerarietum linearifoliae (floresta seca sobre calcários compactos), Lemaireocereo hystricis-Prosopidetum juliflorae (floresta seca perturbada do norte da República Dominicana), Lycio americani-Prosopidetum juliflorae (floresta seca perturbada desenvolvida em solos salinos) Guettardo ellipticae-Guapiretum discoloris (floresta seca em colinas de topo achatado em Montecristi). O trabalho realizado representa um importante avanço nos estudos fitossociológicos e florísticos dos territórios do Caribe., This research paper was possible thanks to the sponsorship of the Agencia Española de Cooperación Internacional para el Desarrollo (AECID), under the auspices of the Ministerio de Asuntos Exteriores y de Cooperación de España, which funded the project (cod. A/3499/05).

Air quality is a major issue for humans owing to the fact that the content of particles in the atmosphere has multiple implications for life quality, ecosystem dynamics and environment. Scientists are therefore particularly interested in discovering the origin of airborne particles. A new method has been developed to model the relationship between the emission surface and the total amount of airborne particles at a given distance, employing olive pollen and olive groves as examples. A third-degree polynomial relationship between the air particles at a particular point and the distance from the source was observed, signifying that the nearest area to a point is not that which is most correlated with its air features. This work allows the origin of airborne particles to be discovered and could be implemented in different disciplines related to atmospheric aerosol, thus providing a new approach with which to discover the dynamics of airborne particles.

The aim of the present study was to develop pheno-meteorological models to explain and forecast the main olive flowering phenological phases within the Mediterranean basin, across a latitudinal and longitudinal gradient that includes Tunisia, Spain, and Italy. To analyze the aerobiological sampling points, study periods from 13 years (1999-2011) to 19 years (1993-2011) were used. The forecasting models were constructed using partial least-squares regression, considering both the flowering start and full-flowering dates as dependent variables. The percentages of variance explained by the full-flowering models (mean 84 %) were greater than those explained by the flowering start models (mean 77 %). Moreover, given the time lag from the North African areas to the central Mediterranean areas in the main olive flowering dates, the regional full-flowering predictive models are proposed as the most useful to improve the knowledge of the influence of climate on the olive tree floral phenology. The meteorological parameters related to the previous autumn and both the winter and the spring seasons, and above all the temperatures, regulate the reproductive phenology of olive trees in the Mediterranean area. The mean anticipation of flowering start and full flowering for the future period from 2081 to 2100 was estimated at 10 and 12 days, respectively. One question can be raised: Will the olive trees located in the warmest areas be northward displaced or will they be able to adapt their physiology in response to the higher temperatures? The present study can be considered as an approach to design more detailed future bioclimate research.

The composition of the essential oils of 16 individual plants of Artemisia herba-alba Asso ssp. valentina (Lam.) Marcl. (at the full bloom stage) growing wild in four different locations from southern Spain were investigated by capillary GC and GC–MS in combination with retention indices. Among the 60 identified constituents (accounting for 80.6–95.0% of the oils), 33 have been reported for the first time in Spanish A. herba-alba oil and 17 of them have not been previously described in A. herba-alba oil. From the analysis of the oil samples, it could be deduced that a noticeable chemical polymorphism typified this taxon. Four groups of essential oils exhibited a single compound with percentages near 30% or higher: davanone, 1,8-cineole, chrysanthenone and cis-chrysanthenol. Two further oil types showed p-cymene and cis-chrysanthenyl acetate as major components in moderate amounts (ca. 20%). All of these types of essential oils have not been previously found in A. herba-alba from Spain and the appearance of such considerable amount of p-cymene is described here for the first time in A. herba-alba. # 2003 Published by Elsevier Ltd.

International audience; Olive oil is a major economic resource of the Mediterranean region. Olive crop management can be improved by models that forecast the variable reproductive biology of olive tree. However, the processes controlling olive harvest are complex on large scales. Here, we study the parameters that influence olive fruit production for developing accurate forecasting models. Seventeen aerobiological sampling points have monitored olive pollen grains in Spain, Italy and Tunisia from 1993 to 2012. Six crop models have been developed at two provinces and country scales. The modelling has been done in two steps: (1) typification and (2) modelling by partial least square regression. Results show that higher pollen indexes and water availability during spring are related to an increase of final fruit production in all the studied area. Higher pollen indexes are also positively correlated with air temperature during early spring and autumn. Furthermore, a decrease of fruit production is related with increasing air temperature during winter and summer. To conclude, we have designed accurate models that allow accurate predictions of olive production.

Detailed knowledge of the spatial distribution of sources is a crucial prerequisite for the application of pollen dispersion models such as, for example, COSMO-ART (COnsortium for Small-scale MOdeling - Aerosols and Reactive Trace gases). However, this input is not available for the allergy-relevant species such as hazel, alder, birch, grass or ragweed. Hence, plant distribution datasets need to be derived from suitable sources. We present an approach to produce such a dataset from existing sources using birch as an example. The basic idea is to construct a birch dataset using a region with good data coverage for calibration and then to extrapolate this relationship to a larger area by using land use classes. We use the Swiss forest inventory (1 km resolution) in combination with a 74-category land use dataset that covers the non-forested areas of Switzerland as well (resolution 100 m). Then we assign birch density categories of 0%, 0. 1%, 0. 5% and 2. 5% to each of the 74 land use categories. The combination of this derived dataset with the birch distribution from the forest inventory yields a fairly accurate birch distribution encompassing entire Switzerland. The land use categories of the Global Land Cover 2000 (GLC2000; Global Land Cover 2000 database, 2003, European Commission, Joint Research Centre; resolution 1 km) are then calibrated with the Swiss dataset in order to derive a Europe-wide birch distribution dataset and aggregated onto the 7 km COSMO-ART grid. This procedure thus assumes that a certain GLC2000 land use category has the same birch density wherever it may occur in Europe. In order to reduce the strict application of this crucial assumption, the birch density distribution as obtained from the previous steps is weighted using the mean Seasonal Pollen Index (SPI; yearly sums of daily pollen concentrations). For future improvement, region-specific birch densities for the GLC2000 categories could be integrated into the mapping procedure. © 2011 ISB.