Encinares luso-extremadurenses y sus etapas preclimácicas

Se comentan las distintas faciaciones de encinar observadas en la provincia corológico luso-extremadurense, dentro de la serie mesomediterráneo de la encina o Quercus rotundifolia Pyro-Querceto rotundifoliae sigmetumWe comment several faciations holm-oak wood's of the Luso-Extremadurense province belonging to the mesomediterranean series Pyro-Querceto rotundifoliae S

Evaluation of admittance domain behavioural model complexity requirements for Power Amplifier design

In the framework of Power Amplifier (PA) design for communications, frequency domain non-linear behavioural models have shown their potential as efficient complementary modelling tools when Field Effect Transistor compact models are not available or sufficiently accurate. The Admittance behavioural model, formulated in the V-I domain, is especially suitable for device size and fundamental frequency scaling. It is important to note that the direct extraction of this model, from the Nonlinear Vector Network Analyser (NVNA) load-pull (LP) measurements, requires some extra processing since it necessitates a Look-up-Table indexed to |V11| rather than |A11|. When using such models in PA design, there is the need for the user to select the necessary model complexity. To address this requirement, in this paper, a systematic analysis methodology, to guide the user, is presented and validated in different PA design scenarios. The methodology was tested using NVNA LP measurements of GaN Heterostructure FETs. A fifth order Admittance model formulation showed good accuracy in the studied PA design scenarios.Agencia Estatal de Investigación | Ref. TEC2017‐88242‐C3‐2‐RXunta de Galicia and European Regional Development Fund - ERDF| Ref. "Centro singular de investigación de Galicia accreditation 2019-2022, atlanTTic

Lamium bifidum Cyr., subsp. Bifidum (Lamiaceae) en el occidente de España

En este artículo se estudia el comportamiento eológico, corológico y sintaxonómico de Lamium bifidum Cyr. subsp. bifidum en España. Se describe una nueva asociación y se adjunta un mapa de la distribución de este taxón en España.In this paper we have studied the e,cologic, chorologic and sintaxonomic behaviour of Lamium bifidum Cyr. subsp, bifidum in the Spain, A new association is described and also we enclose the distribution may of this taxon in the Spain

A classe Cytisetea scopario-striati em Portugal continental

Giestais são a designação vulgar em português para as comunidades silicícolas que se inserem na classe Cytisetea scopario-striati e são dominadas por espécies de leguminosas dos géneros Cytisus, Genista, Adenocarpus e Retama. Esta classe tem o seu óptimo na Península Ibérica e representa normalmente as orlas ou etapas de regressão de bosques climácicos da Quercetalia roboris e da Quercion broteroi. No presente trabalho apresentam-se as diversas comunidades da classe Cytisetea scopario-striati que ocorrem em Portugal continental. Propõem-se os seguintes novos sintáxones: Ulici latebracteati-Cytisetum striati cytisetosum grandiflori, Cytiso multiflori-Retametum sphaerocarpae cytisetosum scoparii, Cytiso multiflori-Retametum sphaerocarpae cytisetosum eriocarpi, Cytisetum cabezudo

Mapa de series, geoseries y geopermaseries de vegetación de España (Memoria del mapa de vegetación potencial de España). Parte II

Peer Reviewe

Behind the scenes: mechanisms regulating climatic patterns of dissolved organic carbon uptake in headwater streams

Large variability in dissolved organic carbon (DOC) uptake rates has been reported for headwater streams, but the causes of this variability are still not well understood. Here we assessed acetate uptake rates across 11 European streams comprising different ecoregions by using whole-reach pulse acetate additions. We evaluated the main climatic and biogeochemical drivers of acetate uptake during two seasonal periods. Our results show a minor influence of sampling periods but a strong effect of climate and dissolved organic matter (DOM) composition on acetate uptake. In particular, mean annual precipitation explained half of the variability of the acetate uptake velocities (VfAcetate) across streams. Temperate streams presented the lowest VfAcetate, together with humic-like DOM and the highest stream respiration rates. In contrast, higher VfAcetate were found in semiarid streams, with protein-like DOM, indicating a dominance of reactive, labile compounds. This, together with lower stream respiration rates and molar ratios of DOC to nitrate, suggests a strong C limitation in semiarid streams, likely due to reduced inputs from the catchment. Overall, this study highlights the interplay of climate and DOM composition and its relevance to understand the biogeochemical mechanisms controlling DOC uptake in streams.Theauthors were supported by the following funding: N. C. by a Generalitat de Catalunya-Beatriu de Pinós grant (BP2016–00215), E. E. by a predoctoral grant from the Basque Government, A. G. B. by a Generalitat de Catalunya-Beatriu de Pinós (BP-00385-2016), A. M. G. F. by a predoctoral research grant (BES-2013-065770) from the Spanish Ministry of Economy and Competitiveness, P. R. L. by a Ramón Areces Foundation Postdoctoral Scholarship, and A. L. by a Kempe Foundation stipend. DOMIPEX project was funded by the First Call of Collaborative Projects among Young Researchers of the Iberian Association of Limnology (AIL; 2013–2015)