Phenological Behaviour of Early Spring Flowering Trees

This chapter reports the phenological trends (reproductive and vegetative events) of some early spring and late winter flowering trees all around the world and especially Europe: Corylus avellana L. (hazel); Quercus robur L. (common oak); Quercus ilex subsp. ballota, (Desf.) Samp. (holm oak); Betula spp. (birch); Salix alba L. (willow); Fraxinus angustifolia Vahl. (ash); and Morus alba L. (white mulberry). They are deciduous and perennial trees growing in different climatic areas of Europe. They have anemophilous pollination liberating huge pollen concentrations to the atmosphere. Aerobiological surveys give us reproductive phenological information of these wind-pollinated species. The phenological response to climate during the last years was analysed, including budburst, leaf unfolding, flowering, fruit ripening, fruit harvesting, leaf colour change, and leaf fall. The response of each taxon to climate was different; most of the revised species and sites presented an advance of the early spring phenophases, especially budburst. On the contrary, some studies detected a delay in autumn vegetative phases, especially leaf fall events. The statistical analyses indicated that phenological advances are a consequence of the increasing temperature trend—minimum temperature being one of the most influential factors. The increase of temperature influenced that leaf unfolding and flowering dates showed a general advance expressed by negative correlations with temperature data, whereas the leaf colour change and leaf- fall presented positive correlations due to the delay of the colder temperatures. The phenological revised results can be considered as reliable and valuable bio-indicators of the impact of the recent climate change in the Northern Hemisphere, and especially Central and Southern Europe

Aplicación de la geoestadística al estudio de la fenología floral de Vulpia geniculllta (L.) Link

XV lnternational A.P.L.E. Symposium of Palynolog

A model to account for variations in holm-oak (Quercus ilex subsp. ballota) acorn production in southern Spain

One of the characteristics of holm-oak acorn production is its high variability among individuals and years. To examine the main causes of this fact, a study was conducted from 1998-2010 in a natural area of holm-oak in southern Spain, where floral phenology, fruit production, fruit size, airborne pollen emission and meteorology factors were analyzed with the ultimate aim of developing a model for forecasting holm-oak yield. Pollen emission during flowering season was the main factor determining the final acorn harvest, but also some meteorological variables played an important role in explaining acorn crop variations, especially humidity and temperature during the months of April and September. The reliability of the proposed model was externally validated using data not included in its construction; validation yielded acceptable results, with a minimum error of estimation. Our results appear to be very useful for planning cropping and pig feeding strategies. Further research could extend the use of airborne pollen counts in forest studies relating to anemophilous species, in order to optimize agricultural policie

Apuntes de derecho registral

La Superintendencia de Notariado y Registro es un organismo que goza de autonomía administrativa y financiera, con personería jurídica y patrimonio independiente, adscrita al Ministerio del Interior y de Justicia. Garantiza la guarda de la fe pública en Colombia mediante la prestación del servicio público registral y la orientación, inspección, vigilancia y control del servicio público notarial; soportada en un sistema de información integral, con talento humano competente y comprometido con los principios de oportunidad y transparencia, para brindar confianza, calidad y seguridad al ciudadano. Se transcribe a continuación el Decreto 1250 de 1970 fechado julio 27, basado en el Diario Oficial No.33.139 del 4 de septiembre de 1970 por el cual se expide el Estatuto de Registro de Instrumentos Públicos

Optimización de modelos predictivos a corto y largo plazo de polen de tipo quercus en distintas zonas climáticas

En este trabajo se han analizado, por un lado, datos: polínicos del tipo Quercus, bioclimáticos y meteorológicos de 14 localidades españolas del periodo 1992-2000. A partir de dichos datos se construyeron modelos de pronóstico para las principales características de la estación polínica de este género en la Península Ibérica: Inicio de la Estación, Concentraciones Diarias, Valor Pico, Día Pico e Indice Polínico Anual. Todos los modelos obtenidos se validaron para años de datos no incluidos en los mismos con excelentes resultados estadísticos. Destacaron las diferencias detectadas entre las variables predictoras que entraron en las ecuaciones propuestas para las localidades de la Región Mediterránea y las de la Región Eurosiberiana. Por otra parte se realizó el análisis del contenido polínico de un punto piloto con vegetación típica Mediterránea donde predominan las especies de hoja perenne del género Quercus, Quercus suber, Quercus coccifera y, fundamentalmente Quercus ilex subsp. Ballota. Este estudio se llevó a cabo durante los años 1998-2000. A su vez, en esta zona, se realizó un seguimiento fenológico tanto de las estructuras reproductoras como de los frutos de Quercus ilex subsp. Ballota (encina). Las concentraciones del tipo polínico Quercus en la zona, los datos de fenología floral y frutal, así como los datos meteorológicos del periodo de estudio se integraron para la creación de un modelo preliminar la previsión de cosecha en encina. Los primeros resultados de este estudio nos revelaron que existe una alta correlación entre datos polínicos y de producción frutal en esta especi

Analysis of the Orchidaceae Diversity in the Pululahua Reserve, Ecuador: Opportunities and Constraints as Regards the Biodiversity Conservation of the Cloud Mountain Forest

The Pululahua Geobotanical Reserve is a protected natural area in the cloud mountain forest of Ecuador, so rich in orchid species despite being a volcanic area still under threat of volcanic activity. A comparative biodiversity study of orchids was carried out in two different sectors, Chaupisacha (CH) and La Reventazón (LR). Data were collected in 1 ha plots in each sector, in which all the orchids found were counted and two individuals of each species were retained. Immature individuals were conserved in a plant nursery until flowering. In CH, there were 922 individuals grouped into 24 genera and 55 species, while LR had 9196 individuals grouped into 26 genera and 46 species; only 14 species were found in both sectors. Different density and diversity indexes were calculated. The density (ind./100 m2) of CH was 0.96, while that of LR was 185.92. Simpson’s diversity (1 − λ) attained CH 0.903 ± 0.01 and LR 0.85 ± 0.01. The orchid diversity measured by the Shannon-Wiener diversity index (H′) was 1.29 for CH, differing significantly from that of LR (H′ 1.02). The medium equity (Jaccard’s J′) found was 0.61 in CH and 90.78 in LR. Limitations as regards the natural dispersion of orchids seemed to favor endemism. Some species, such as Dracula felix and Restrepia guttulate, are threatened with disappearance from the wild or are vulnerable, as is the case for Epidendrum polyanthogastrium. A lack of information on the phenology and anthropic impacts in the area limit the conservation of species, signifying that new protected figures and seed banks are necessary, especially in CH, owing to its high diversity of orchids

Long-term trends in atmospheric Quercus pollen related to climate change in southern Spain: A 25-year perspective

Long-term trends of atmospheric Quercus pollen recorded for 25 years (1995–2019) in southern Spain (Cordoba city, Andalusia region) have been studied to determine the influence of climate fluctuations and other anthropogenic factors on Mediterranean oak vegetation areas. Atmospheric pollen analysis revealed different changes on reproductive Quercus phenology through the study period. Pollination intensity showed an average cumulated value of the Main Pollen Season Integral of 12,832 Pollen * day/m3, with a high variability among years (±SD 8,048) and a significant rising trend of 771 pollen grains per year, being stronger in recent years (2014–2019). It was remarkable the high quantity of Quercus pollen grains detected out of the Main Pollen Season (703 Pollen * day/m3 ± SD 431), also increasing in recent years. Regarding Quercus phenology, results indicated as the main Quercus species in the area, Quercus ilex subsp. ballota (holm oak), Q. coccifera, Q. faginea and Q. suber, presented a gradually pollination during spring (from mid-March to early June), although a lengthening of the pollination season is observed in recent years. This phenomenon could be explained by the progressive delay in the pollination of Q. suber. Regarding climate factors, a decrease in rainfall, especially during winter and autumn was recorded, along with colder winters but warmer springs, summers, and autumns. These changes were significantly correlated with pollination timing and intensity. The climate parameters most affecting were those related to temperature and sunshine. However, the total annual pollen showed a significant negative correlation with the annual recorded rainfall. Results show that recent climatic change, among other factors, are leading to changes in the timing and intensity of the Quercus pollen season in the Mediterranean area

Factors Driving Autumn Quercus Flowering in a Thermo-Mediterranean Area

The flowering period of plants is a critical time since it determines their reproductive success. Flowering is controlled by different factors including genetic regulation and environmental conditions. In the Mediterranean area, favourable conditions usually occur in spring, when most plant species flower including those of the Mediterranean Quercus genus. This paper reveals and analyses an unusual and lesser-known phenomenon occurring in the two main Mediterranean agroforestry ecosystems of South Europe, the Mediterranean forest and “dehesa”, that is, a second flowering occurring in autumn for the species Quercus ilex subsp. ballota (holm oak). The continuous pollen monitoring of the atmosphere in the city of Cordoba (southern Spain) for 25 years, together with field phenological observations in the area, has indicated that, apart from the main pollination period in spring, secondary flowerings also occasionally occur in this area, specifically in autumn. The present work examines these uncommon pollination events detected in the autumns of certain years with the aim of determining the main environmental factors that influence and control them. During the 25-year study period, there were 7 years in which a secondary Quercus flowering was detected in the area from the second half of October until the end of November. The univariate statistical analysis of the influence of environmental variables determined that the meteorological conditions in September were the most influential. Low mean temperatures, together with record rainfall in that month, led to autumn flowering events. The phenological characteristics of the spring pollen season were also influential. In the years with a shorter spring, the Quercus pollen season tended to present autumn flowerings. A multivariate adaptive regression splines (MARS) model was built to explain the effects of the different variables on the occurrence of autumn pollination. The results indicated that the combined effect of three predicting variables, September rainfall, the length of the spring pollen season, and the end of the spring pollen season, explained 92% of the variance. The validation showed a strong relationship between the expected and the observed autumn pollen concentrations. Therefore, the present analysis of a long-term pollen database revealed that the main causes of this unusual second flowering in autumn were strongly related to climate change, i.e., strong dry summers and warm autumns. In addition, the results showed that the phenomenon was more frequent in the years with low pollination during spring due to different meteorological events potentiated by climate change, such as dryness or heavy rain episodes, as a way of ensuring acorn crops. The results explain how this unusual and lesser-known phenomenon in agroforestry dynamics is related to the adaptation to climate change and the main factors that are driving it, as well as the potential consequences for these important and endangered Mediterranean ecosystems

Mecanismos articulados: Geometría Dinámica y Cinemática en un entorno educativo STEM

A concrete proposal for using a Dynamic Geometry System at an educational setting in a STEM environment (Science, Technology, Engineering and Mathematics) and, particularly, in the subject of Mathematics, consists on the generation and handling of digital simulations of mechanical linkages.Herein, in this article we collect proposals arguing for the teaching of mechanical models or articulated mechanisms and curve drawing devices in particular, as a path to apply complex mathematical ideas and notions which are based on Dynamic Geometry. In addition, this perspective constitute a powerful resource for the iniciation and reproduction of historical contexts of scientific experience in the classroom.We present two digital repositories of articulated mechanisms, the Kinematics Models For Design Digital Library and the Laboratorio delle Macchine Matematiche together with a review of educative proposals dealing with these mechanisms.Una propuesta concreta de uso de un Sistema de Geometría Dinámica en un entorno educativo STEM (Science, Technology, Engineering and Mathematics) en general y en la asignatura de Matemáticas en particular, consiste en el estudio, manipulación y generación de simulaciones digitales de mecanismos articulados.En este artículo recopilamos propuestas que  argumentan a favor del uso de modelos mecánicos o articulados de mecanismos, en particular los utilizados para dibujar o trazar curvas, como un medio de generación de ideas o nociones matemáticas complejas apoyados por las posibilidades de la Geometría Dinámica. Además, este enfoque supone un recurso muy efectivo para la introducción en el aula de contextos históricos de recreación de la experiencia científica.Presentamos dos repositorios digitales de mecanismos articulados, la Kinematics Models For Design Digital Library y el Laboratorio delle Macchine Matematiche así como una revisión de propuestas didácticas del uso educativo de este tipo de mecanismos