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1.
Summary The practical aim of our research work was to point out the advantages of a deeper knowledge of botanical data in allergology. Aerobiological monitoring is not enough for an analysis of the formation and development of pollen rain. The following emphasizes the importance of interdisciplinary studies in the approach to the pollinosis problem: — A phytogeographical study in the area investigated has made it possible a) to ascertain the correlation between aerobiological and phytogeographical data and to understand the reasons of some of the discordances, b) to select an allergen panel for testing including pollens of species peculiar to that particular region; a more accurate appreciation of the distribution of different allergenic pollen source areas in the light of local meteorological conditions, will be an excellent guideline for the interpretation and prediction of symptoms in allergic patients. — A phenological checking of the flowering period on location for allergenic species in the area next to the sampling station has made it possible to assess the flowering interval and peak for each species and to attribute the responsibility for the pollen and symptom peaks to a particular species within the same family at a specific moment. The above data are the basis and sometimes the only support available for the interpretation of aerobiological data.  相似文献   

2.
Recent anthropogenic climate change is strongly associated with average shifts toward earlier seasonal timing of activity (phenology) in temperate-zone species. Shifts in phenology have the potential to alter ecological interactions, to the detriment of one or more interacting species. Recent models predict that detrimental phenological mismatch may increasingly occur between plants and their pollinators. One way to test this prediction is to examine data from ecological communities that experience large annual weather fluctuations. Taking this approach, we analyzed interactions over a four-year period among 132 plant species and 665 pollinating insect species within a Mediterranean community. For each plant species we recorded onset and duration of flowering and number of pollinator species. Flowering onset varied among years, and a year of earlier flowering of a species tended to be a year of fewer species pollinating its flowers. This relationship was attributable principally to early-flowering species, suggesting that shifts toward earlier phenology driven by climate change may reduce pollination services due to phenological mismatch. Earlier flowering onset of a species also was associated with prolonged flowering duration, but it is not certain that this will counterbalance any negative effects of lower pollinator species richness on plant reproductive success. Among plants with different life histories, annuals were more severely affected by flowering–pollinator mismatches than perennials. Specialized plant species (those attracting a smaller number of pollinator species) did not experience disproportionate interannual fluctuations in phenology. Thus they do not appear to be faced with disproportionate fluctuations in pollinator species richness, contrary to the expectation that specialists are at greatest risk of losing mutualistic interactions because of climate change.  相似文献   

3.
The intensification of agriculture has significant environmental consequences. This intensification entails the simplification and homogenisation of the landscape, which leads to strong negative impacts at ecosystem level, including declines in animal biodiversity. The purpose of this study was to assess the effect of different land uses on reptilian and amphibian biodiversity patterns at a regional scale by analysing a large database on the presence of amphibians and reptiles in Andalusia (southern Spain). GIS techniques and the Ecological-Niche Factor Analysis (ENFA) were applied in order to assess whether the habitat was suitable for each reptilian and amphibian species, when the land use variables were excluded. The incongruence between the potential and the observed species richness was then correlated with the main types of land use in Andalusia. Our results showed that irrigated and unirrigated olive groves were associated with a biodiversity deficit of amphibians and reptiles respectively, whereas natural forests and pastures, along with more heterogeneous crops areas, were more suitable. A clustering analysis showed that generalist species were related to olive groves whereas rare and specialist species were related to land uses related to natural vegetation. In summary, our results indicate that large areas covered by olives groves harbour less amphibian and reptilian diversity, thus suggesting that agro-environmental schemes should be carried to promote the species richness in these crops.  相似文献   

4.
Knowledge about the timing of the aerobiological and phenological processes in plants with economic interest results of great agronomical importance, mainly for the establishment of the adaptive capacity of different varieties to various environmental conditions and the optimization of cultural practices. An agrometeorological study in two authorized varieties (Treixadura and Godello) of the Designation of Origin Ribeiro (North-western Spain) was conducted during the years 2008–2011. As consequence of the studied area bioclimatic conditions, the grapevine cycle exceed than 190 days and the varieties cultivated are considered as “late varieties.” The presence of Vitis pollen grains in the vineyard atmosphere was mainly registered during the stages 5 (inflorescence emerge) and 6 (flowering) which benefit a successful fertilization process. The variations in airborne pollen concentrations are related to temperature and humidity. Phenological models proposed in this paper offer a high accuracy as the standard deviation of error between estimated and observed values was low. The prediction variability ranges around 2 phenological scales in 2008 and 1 phenological scale in 2009, 2010 and 2011. These results indicate that the models developed to predict the phenology, in terms of degree days accumulated (GDD) using as a threshold temperature 10 °C, can be a useful tool to forecast the successive phenological events in the Designation of Origin Ribeiro area. During the stage 8 (ripening of berries), the GDD and the Brix Index were particularly correlated, so far as the differences between plants of the same variety are minimal.  相似文献   

5.
Dynamics of the predatory arthropod community in Spanish olive groves   总被引:1,自引:1,他引:1  
1 A survey of the predatory fauna of olive pests, particularly the olive moth, Prays oleae, was undertaken in Granada, Spain, from May to September 1994–95. 2 At both experimental sites similar patterns of emergence were observed for all predatory species with peaks occurring in June, both in 1994 and 1995. More individuals and species were captured in the morning than in the evening. 3 A weak inverse relationship existed between the mean monthly temperatures and the total number of predators caught. 4 The number of predatory species and of individuals caught at both sites was, respectively, two and three times larger in 1994 than in 1995; This difference is assumed to have been due to the accumulated affect of 6 years of drought. 5 Synchrony between P. oleae and predator phenology was suggested by the coincidental timing of peak predator numbers with the oviposition and subsequent emergence of the most vulnerable stage of the olive moth’s lifecycle, i.e. the flower generation. 6 There were more individuals of ants caught, whilst more spider species were captured than all other groups; predatory Coleoptera and Heteroptera were poorly represented. 7 Ants appeared to have a detrimental affect on the number of all other predators.  相似文献   

6.
7.
The paper describes phenological and aerobiological monitoring conducted during 6 years on a potato crop. The progression of the phenological stages in relation with thermal time [growing degree-days (GDD) and physiological days (P-days)] was analyzed. The growing cycle for Kennebec variety required less than 120 days and mean values of 1700 GDD and 720 P-days to complete the phenological development. The presence of Phytophthora infestans in the environment was common in each crop cycle, but the maximum peaks of sporangia were detected a few days after the emergence of the plants. The growing cycles with lower maximum temperature had the highest presence of sporangia. Thus, significant negative correlations between mean temperature, maximum temperature, accumulated growing degree-days, accumulated physiological days and the concentration of P. infestans in the environment were found. Maximum temperature and accumulated growing degree-days of 5 previous days were the parameters that best estimated the P. Infestans concentration in the regression model applied, with an explained variance of the data of 33 and 34%.  相似文献   

8.
Analysis of progress curves for enzyme-catalyzed reactions has been made by using a procedure that does not require the derivation of complex integrated rate equations. The method involves conversion of progress curve data to reaction velocities that are then fitted to the appropriate differential rate equation. Application of the procedure to data obtained for the reaction catalyzed by aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1), showed that the resulting values for the kinetic parameters agreed well with those obtained by conventional progress curve analysis (Duggleby, R.G. and Morrison, J.F. (1978) Biochim. Biophys. Acta 526, 398--409).  相似文献   

9.
Summary Studies on ragweed have been carried out in the province of Trieste (Northern Italy) in which it is becoming widespread. The floristic records, the increasing amount of airborne pollen monitored and the relevant skin reactivity are reported. This phenomenon, though still at the beginning, is actually showing an upward trend due to man's intervention over wider and wider areas which as a consequence become suitable for the settlement of these anthropophitic species. The aerobiological data are compared to the skin reactivities of allergic subjects.  相似文献   

10.
Bruno Romano 《Aerobiologia》1988,4(1-2):20-26
Summary The results of six years (1982–1987) of aerobiological study in Perugia (central Italy) are reported. During this period a total of 80 different types of pollen belonging to 52 families were identified in the Perugia atmosphere. The highest percentages of pollens were found in the mid-March to mid-July period. For main taxa principal periods of pollination were identified. The outlines for the weekly issue in a newspaper of the concentration pattern of the allergenic pollens are reported.  相似文献   

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新疆野杏(Prunus armeniaca Lam.)是天山野果林的优势种,具有重要的生态与资源价值。野果林的生境条件与其分布及生长密切相关。为了明确新疆野杏在不同海拔下的开花物候与花器官变化规律,于2021年3月—4月,选择新疆新源县吐尔根杏花沟野杏林为研究区,在野杏集中分布的1000—1500m的山地,由低到高划分Ⅰ—Ⅴ级海拔梯度设置样地,监测环境条件,对野杏群体开花物候期与花器官发育特征进行调查。结果表明:(1)新疆野杏群体开花物候期历时32d左右,各海拔梯度最长相差2d,第Ⅰ级与第Ⅱ级海拔的开花物候期差异不明显,其他海拔梯度间均存在显著差异,开花最晚的第Ⅴ级比最早的第Ⅰ级晚9d,但群体开花期长4d,海拔梯度与开花物候期呈显著正相关,而温度与开花物候期呈显著负相关;(2)新疆野杏的花萼长度和宽度、子房高度和宽度均是第Ⅱ级海拔的最大;花冠直径、花瓣纵径和横径均是第Ⅰ级的最大,花药长度和宽度均是第Ⅳ级的最大;花柱长度是第Ⅴ级的最大。海拔与花的外部器官、雌蕊呈显著负相关,与雄蕊呈显著正相关;光照强度与花的外部器官、雌蕊呈显著负相关;(3)新疆野杏开花期气候因子,第Ⅳ级、第Ⅴ级与第Ⅰ级存...  相似文献   

14.
Flowering time is a well-studied subject in ecology, evolution and molecular biology. Long-term phenological studies have shown relationships between flowering time and environmental and endogenous factors in many species. In contrast, molecular studies using model plants have revealed a complex regulatory network of flowering. We propose that flowering would be a model trait for the integrated study of ecology, evolution and molecular biology. We introduce briefly the flowering regulatory pathways of Arabidopsis thaliana, followed by molecular techniques such as transgenic manipulation, quantitative real-time PCR and detection of differentially expressed genes that could facilitate the study of ‘nonmodel’ species of ecological interest but with little available genome information. Application of the flowering gene network to wild species will be illustrated by two examples: modeling and prediction of the expression of flowering genes in Arabidopsis halleri, and the latitudinal cline of bud set and cessation in Populus. Finally, we discuss the challenges in integrating knowledge of the regulatory network on flowering into ecologically unique flowering phenomena such as synchronous intermittent mass flowering—the topic of this special issue.  相似文献   

15.
An atmospheric pollen survey and a periodical quantitative check of the flowering phases of trees were performed during 1993. Most of specific flowering seasons lasted from 4 to 8 weeks. October is the month with the highest number of species in bloom. Anemophylous species flower mainly in coincidence with the relatively low temperatures of late winter and early spring, while the enthomophylous ones correlate with the high temperatures of late spring and summer. The anemophylous ‘community’ follow a sigmoid pattern with respect to both the flowering development and the cumulative pollen concentration. Agreement between floral phenophases and pollen counts were evaluated for 14 genera (27 species). Pollen data of anemophylous species coincide fairly well with the phenological behaviour. Particular features must be taken into account to interpret this relationship.  相似文献   

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17.
The diversity and abundance of wild bees ensures the delivery of pollination services and the maintenance of ecosystem diversity. As previous studies carried out in Central Europe and the US have shown, bee diversity and abundance is influenced by the structure and the composition of the surrounding landscape. Comparable studies have so far not been carried out in the Mediterranean region. The present study examines the influence of Mediterranean landscape context on the diversity and abundance of wild bees. To do this, we sampled bees in 13 sites in olive groves on Lesvos Island, Greece. Bees were assigned to five categories consisting of three body size groups (small, medium and large bees), the single most abundant bee species (Lasioglossum marginatum) and all species combined. The influence of the landscape context on bee abundance and species richness was assessed at five radii (250, 500, 750, 1000 and 1250 m) from the centre of each site. We found that the abundance within bee groups was influenced differently by different landscape parameters and land covers, whereas species richness was unaffected. Generally, smaller bees' abundance was impacted by landscape parameters at smaller scales and larger bees at larger scales. The land cover that influenced bee abundance positively was olive grove, while phrygana, conifer forest, broad-leaved forest, cultivated land, rock, urban areas and sea had mostly negative or no impact. We stress the need for a holistic approach, including all land covers, when assessing the effects of landscape context on bee diversity and abundance in the Mediterranean.  相似文献   

18.
The possible existence of altitudinal fluctuations in the seasonal behaviour of the olive pollen emission was studied. Three pollen volumetric samplers distributed in olive groves all over the altitudinal cliseries of the province of Jaén (south-east Spain) were used. Pollen emission data were recorded during a 3-year period (2007–2009). This research has revealed the effect of altitude on consecutive olive pollen season in the province of Jaén. The first pollen grains were detected in the olive growing areas located within the area of the Guadalquivir River, where are found the lowest levels of altitude into the province. A notable delay in the pollination season of the olive groves located at higher altitudes was observed. Geographical fluctuations on both daily pollen concentrations and number of critical days were also detected. Accumulated variables of temperature and precipitation since the start of the pre-flowering period have been shown to be two of the main factors affecting olive pollen levels. The fluctuations observed in the olive pollen season may similarly occur in the case of other allergenic plant species such as cypress (Cupressaceae), plane tree (Platanaceae) or grasses (Poaceae). Furthermore, and for the clinical consequences of the findings presented in this study, we believe that it would be advisable to install a micro-aerobiological network permanently in the province of Jaén.  相似文献   

19.
Aims Exploring flowering patterns and detecting processes are essential when probing into the nature of reproductive traits during the life history and the interactions among different evolutionary clades. Such patterns are believed to be influenced by many factors, but quantifying these impacts at the community-level remains poorly understood.Methods We investigated the flowering patterns based on long-term herbarium records in a given area from subtropical forest regions in southern China. We obtained 5258 herbarium voucher specimens collected from the Dinghushan National Nature Reserve (DNNR) belonging to 166 families, 943 genera and 2059 species and examined the month when each species was flowering during the period 1920–2007.Important findings The results showed that plants flowered sequentially almost throughout the whole year, showing the characteristics of subtropical evergreen broad-leaved forests. Flowering spectrums of the entire flora and the four life forms exhibited a clear unimodality that is probably typical of subtropical forest communities. Flowering patterns of the DNNR were positively correlated with mean rainfall, mean air temperature and mean sunshine duration. Median flowering dates of the 38 large species-rich families ranged from early April to late August; 25 families exhibited significant unimodal distribution patterns, whereas the remaining families were unclear or bimodal. Median flowering dates of the 10 most species-rich genera ranged from middle May to later July. While the results are consistent with climatic factors playing a general role in flowering patterns, median flowering dates varied significantly among species-rich families and genera, suggesting that phylogenies could provide specific constraints in subtropical forests.  相似文献   

20.
The flowering period and flower colour spectrum of 170 aromatic plant species are studied in 18 representative regions in Greece. The duration of the early to late flowering of the species is recorded for each region and for Greece as a whole. The basic flower colours (green, yellow, red and violet) are defined and the colour spectra for each region and for the whole country are given by converting absolute to relative values. The Sørensen similarity coefficient is applied to compare regions and the relationship among them as well as with a control region (Athos peninsula). Conclusions are drawn as to the time of maximum flowering and the decrease in the proportion of flowering species from north to south. In addition, interpretations are given for the symmetrical flowering curve of Greece as a whole, compared to the skewed curves of the islands.Nomenclature follows T. G. Tutin et al. (eds.) 1964–1980. Flora Europaea 1-5, Cambridge.  相似文献   

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