91 research outputs found
Paleovegetación durante la Edad del Bronce en la Rioja alavesa: Análisis palinológico del yacimiento de Peña Parda ( Laguardia, Álava)
En este trabajo se presenta el estudio palinológico del yacimiento de Peña Parda (Laguardia,
Álava). Los resultados obtenidos, en las 13 muestras estudiadas, han aportado interesantes datos sobre el
paisaje vegetal existente en la vertiente sur de la Sierra de Cantabria durante la Edad del Bronce, así como sobre
las evidencias de antropización
Potencial paleoecológico de los depósitos orgánicos marinos de Posidonia oceanica
XV lnternational A.P.L.E. Symposium of Palynolog
Pollen feeding habits of Chrysoperla carnea s.l. adults in the olive grove agroecosystem
Chrysoperla carnea s.l. (Stephens) larvae are important natural enemies in agroecosystems. However, adults feed
on honeydew excreted by hemipterans, and pollen and nectar from flowering plants. Pollen is essential for egg
production, but to our knowledge, the pollen diet of C. carnea in perennial crops has never been addressed. In
this work, the objective was to study the diversity and potential selection of pollen types consumed by C. carnea
in the olive grove agroecosystem. For this study, C. carnea adults were captured from April to December of 2012
and 2013, and simultaneously, inventories of the plant diversity were obtained in olive orchards and adjacent
scrubland and herbaceous patches. The pollen types contained in C. carnea guts were identified by microscopy
and compared with the pollen types in the environment using Jacobs`s second selection index. The results
indicated that (i) C. carnea females and males captured in the olive tree canopy visited scrub and herbaceous
vegetation patches; (ii) they fed on different anemophilous and entomophilous pollen types from tree and scrub
(Olea europaea, Fabaceae, Pinaceae, Cistaceae or Ericaceae) and herbaceous (Asteraceae, Apicaceae,
Brassicaceae, Poaceae, Rumex type or Plantago type) strata; and (iii) adults fed not only on flowers but also on
pollen settled on vegetation surfaces. Here, we demonstrated that C. carnea could benefit not only from the
diversity of entomophilous pollen during the plant flowering periods but also from other pollens that could
remain in the environment in different periods. This has important implications for the management of the floral
diversity adjacent to the crop.The authors are grateful to the Portuguese Foundation of Science
and Technology for financial support through the project EXCL/AGRPRO/
0591/2012 “Olive crop protection in sustainable production
under global climatic changes: linking ecological infrastructures to
ecosystem functions.” M.V. thanks FCT, PostDoc grant (SFRH/BPD/
119487/2016).info:eu-repo/semantics/publishedVersio
Peatlands in the Toledo Mountains (central Spain): characterisation and conservation status.
We have limited knowledge about the biodiversity and vulnerability of peatlands in the lower-altitude mountains of the Iberian Peninsula, largely because peatlands have not been routinely differentiated from other habitat types in Spain. Understanding is now developing about the ecology of peatlands in central Spain, but they are already under severe threat of conversion and degradation. In this article we describe the results of a field survey and literature review study to characterise and describe the current condition of peatlands in the Toledo Mountains in terms of their typology, the representation of habitat types protected by European (EU) designations, threats, endangered plant species, and conservation status. Our results suggest that the principal threats are overgrazing by domestic animals and ungulates (red deer and wild boar), fire, expansion of cereal crops, drying-out and erosion. Disturbance is most severe in areas that are not protected by nature conservation designations, where peatlands are especially vulnerable to damage arising from human activities
Paleopaisaje y dinámica antrópica durante la Protohistoria alavesa. Una perspectiva paleoambiental
El trabajo que figura a continuación trata de ofrecer una visión sintética sobre la
historia de la vegetación, la dinámica antrópica y la evolución climática del período protohistórico en un sector muy concreto del valle del Ebro, el Territorio Histórico de Álava. Para ello, se ha empleado una herramienta paleoambiental de gran interés, el estudio de los microfósiles
polínicos y no polínicos preservados en depósitos de diferente tipología de la Edad del Bronce y la Edad del Hierro, con el objetivo de aportar datos y reflexiones a diferentes problemáticas relativas a los cambios culturales.------------------This paper shows a synthectic view of the vegetation history, the anthropogenic
dymamic and the climatic evolution of the Protohistoric period in a very specific sector of the Ebro Valley, the present province of Alava. To this end, we have used a palaeoenvironmental tool of great interest, the study of pollen, spores and non‐pollen palynomorphs preserved in several different deposits of the Bronze Age and Iron Age, in order to provide data and reflections to different problems related with cultural changes
Vulnerability and resilience of high-mountain pine forests of the Gredos range (Ávila, Spanish Central System): two thousand years of socio-ecological dynamics
RESUMEN: En este trabajo se presenta el análisis palinológico de la turbera de Pozo de la Nieve, localizada en el Parque Natural del Valle de Iruelas (Ávila), un área de alto valor sociocultural dentro de la Sierra de Gredos (Sistema Central). Con el objetivo de relacionar los cambios en el paisaje con la explotación de los recursos naturales y eventos climáticos, en primer lugar se han realizado 7 dataciones radiocarbónicas que sitúan el inicio del registro sedimentario ca. 240 cal BC. Los datos polínicos indican la existencia de un denso pinar altimontano dominado por Pinus sylvestris/nigra desde la Segunda Edad de Hierro hasta el periodo islámico. A partir del periodo cristiano las actividades antrópicas se intensifican, especialmente la ganadería en la Edad Contemporánea, lo cual conlleva la progresiva desaparición del pinar de alta montaña y el desarrollo de pastizales mediante el manejo del fuego, situación que culmina con el desarrollo del paisaje actual dominado por piornales pirófilos.ABSTRACT: We present the palynological study of Pozo de la Nieve peat bog, located in a very valuable socio-cultural placement within the Iruelas Valley Natural Park (Gredos range, Iberian Central System). We have focused in relating landscape changes to natural resources management and climatic events. Firstly, we carried out seven radiocarbon dates suggesting the origin of this record ca. 240 cal BC. The palynological data show the existence of dense high-mountain pine woodlands dominated by Pinus sylvestris/nigra from the Late Iron Age to the Muslim period. Later, from the Christian period, anthropogenic activities have intensified, especially livestock grazing in the Contemporary Age. Its consequences are the progressive disappearance of highmountain pine forests and the extension of grasslands by means of fire, which has shaped current landscape dominated by broom communities.Este trabajo ha sido financiado por el proyecto
Desirè-HAR2013-43701-P (Plan Nacional
I+D+I, Ministerio de Economía y Competitividad
de España). Sebastián Pérez Díaz está
financiado por el Programa Estatal de Promoción
del Talento y su Empleabilidad en I+D+i
en la modalidad Juan de la Cierva-Incorporación.
Mónica Ruiz Alonso está financiada por
el Programa Estatal de Promoción del Talento
y su Empleabilidad en I+D+i en la modalidad
Juan de la Cierva-Formación
Biodiversity and pollen feeding habits of syrphids in olive groves and surrounding landscape in Northeastern Portugal during spring
Many syrphid larvae are predators of aphids and early stages of moths and psyllids, being potential control agents of some olive pests. However, adults need pollen and nectar for energy and reproduction. An increase of plant resources biodiversity in heterogeneous landscape could benefit these natural enemies. Thus, our goal of was to study the syrphid biodiversity and their pollen sources in olive agroecosystems from the northeast of Portugal during spring, that coincides with the availability of pests. For that, syrphids were captured in three not-tilled olive groves and two surrounding field areas (an herbaceous vegetation patch and a scrubland) next to each olive grove. Simultaneously, flowering plant inventories were carried out. Syrphids and the pollen contained in the guts of the most abundant species were identified. Thereafter pollen in guts was compared with pollen in the environment to evaluate a potential pollen selection. The most abundant species were Sphaerophoria scripta and Melanostoma mellinum. During the spring syrphids did not consume all the occurring plant species but did not actively selected pollen types. Results indicated that Asteraceae, Plantaginaceae, Caryophyllaceae, Echium type, Rumex type and Jasione type are important food sources for M. mellinum and S. scripta. These results will allow managing ground cover vegetation more efficiently in order to conserve syrphids in the olive agroecosystem.M. Villa is grateful to the Foundation for Science and Technology (Portugal) for the postdoctoral grant SFRH/BPD/119487/2016info:eu-repo/semantics/publishedVersio
Syrphids feed on multiple patches in heterogeneous agricultural landscapes during the autumn season, a period of food scarcity
Many syrphid larvae are predators and have an important role as biological control agents of pests in agroecosystems. However, adults feed on non-prey resources such as pollen from flowers. Heterogeneous landscapes can provide syrphids with a great biodiversity of plants and ensure the existence of food resources. This is particularly important during periods of food scarcity, such as autumn, for syrphid species that spend those periods as adults. Nevertheless, the feeding habits of syrphid adults in resource-scarce agroecosystems are poorly known. In this study, the pollen consumption and preferences of Eupeodes corollae (Fabricius) and Episyrphus balteatus (De Geer) were analyzed in olive groves and surrounding herbaceous and woody patches in the autumns of 2012 and 2013 in northeastern Portugal. The guts were dissected, and the pollen types were identified and compared with the ground cover plants in the studied patches. Both species consumed and selected pollen types from herbaceous and woody vegetation that occurred in different patches, indicating that they flew between patches. These results highlight the importance of conserving heterogeneous agricultural landscapes to guarantee the existence of food resources for beneficial insects during periods of scarcity.The authors are grateful to the Foundation for Science and
Technology (Portugal) and COMPETE/QREN/EU for
financial
support through the research project EXCL/AGR-PRO/0591/2012:
Olive crop protection in sustainable production under global
climatic changes: linking ecological infrastructures to ecosystem
functions and for grant SFRH/BD/70693/2010 awarded to M. Villa.
The authors are also grateful to Carlos Aguiar for help with the
plant species identification.info:eu-repo/semantics/publishedVersio
Iberian acid peatlands: types, origin and general trends of development.
ABSTRACT: In the present study we reviewed the genesis, development and classification of peatlands in the Iberian 1. The region has a wide variety of peatlands which are classified according to their biogeochemical, geomorphological and ecological characteristics into different types of bogs and fens. 2. Most of the peatlands occur in the Atlantic region followed by the Mediterranean and Alpine regions. Fens are more widely distributed than bogs, and blanket and raised bogs are mainly found in the Eurosiberian biogeographical region. 3. In many of the fens, the last active peat-forming cycle occurred during the Late Holocene (43 %). In most of the bogs, the peat-forming cycle occurred in the Middle Holocene (70 %), although in a substantial proportion of blanket bogs these processes occurred in the Early Holocene (30 %). 4. The peat formed in the last active cycle is, on average, thicker in raised bogs (322 cm) than in blanket bogs (257 cm) and fens (156 cm). 5. Vertical peat accumulation rates varied between 16 and 30 yr cm-1 in more than 40 % of the peatlands. The accumulation rates differed significantly between the different types of peatlands and were highest in the raised bogs. The accumulation rates were very variable in the fens. 6. The genesis, evolution and types of Iberian peatlands are similar to those observed in peatlands in northern latitudes in Europe and North America.Our research has been made possible by the following project grants: INCITE09-200-019-PR (Xunta de Galicia Government); DESIRÈ-HAR2013-43701-P (Spanish Ministry of Economy and Competitiveness); and Relictflora-P11-RNM-7033 (Excellence Research Projects Program from the Andalusian Government)
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