895 research outputs found
Hierarchical habitat-use by an endangered steppe bird in fragmented landscapes is associated with large connected patches and high food availability
Multidimensional approaches must be employed when addressing habitat use patterns. In this study, we aim to elucidate the hierarchical nature of space use by species inhabiting fragmented landscapes, using the threatened Dupont’s lark (Chersophilus duponti). The intensity of space use by Dupont’s lark was estimated using the Kernel Density Function on territory locations in 2015. We measured descriptors of habitat quality at metapopulation (connectivity and patch size), landscape (land-use types and anthropogenic disturbance) and microhabitat-scale (plant structure and composition, herbivore abundance and food availability) at 37 sampling stations. We fitted a Partial Least Squares Regression (PLSR) which yielded two components, accounting for 81% of total variance. Metapopulation-scale factors had the greatest explanatory power (32%), followed by microhabitat (17%) landscape (10%) and spatial predictors (3.6%). Connectivity and patch size were key factors explaining habitat use, and wind farms had a negative effect. At microhabitat-scale, space use was positively associated with Coleoptera, Orthoptera, Araneae and Diptera biomass, but negatively with Formicidae and Blattodea biomass, the cover of Stipa spp, Koeleria vallesiana and moss. This research highlights the hierarchical nature of habitat use in fragmented landscapes. Therefore, conservation measures should ensure connectivity, guarantee a minimum patch size, and improve habitat quality within patchesWe wish to thank Luis M. Carrascal for the help with statistical analysis. In addition, we are grateful to Álvaro Ortega, Jonathan Pereira and Carlos Talabante for their help with arthropods identification, and to Iris Calleja, Rodrigo A. Martínez, Laura Aylagas and Jaqueline Boldt for their help during fieldwork. We are grateful to two anonymous reviewers for their constructive comments that helped to improve the manuscript. This study was supported by Fundación Patrimonio Natural de Castilla y León, the European Commission (Life-Ricotí project LIFE15-NAT-ES-000802) and the BBVA Foundation (BBVA-Dron Ricotí project). This paper contributes to project REMEDINAL-3 from CAM
Aplicaciones de SIG y teledetección en ecología: Guión de prácticas de la asignatura
Este
trabajo
surge
como
resultado
del
Proyecto
de
Innovación
Docente
de
la
Universidad
Autónoma
de
Madrid
–
Convocatoria
2013:
Adaptación
de
los
recursos
informáticos
de
la
asignatura
“Aplicaciones
de
SIG
y
Teledetección
en
Ecología”
del
Máster
Oficial
en
Ecología
para
la
utilización
de
herramientas
de
software
libre,
y
elaboración
del
manual
de
las
prácticas,
coordinado
por
Juan
Traba
y
con
la
participación
de
Javier
Seoane
y
Manuel
B.
Morales;
los
tres
son
profesores
titulares
del
Departamento
de
Ecología
de
la
Universidad
Autónoma
de
Madrid.
Ester
González
de
Andrés
ha
disfrutado
de
una
beca
financiada
por
la
la
UAM
durante
la
realización
de
este
proyecto.
Queremos
agradecer
expresamente
la
imprescindible
participación
de
Mª
Paula
Delgado,
Irene
Guerrero
y
Pablo
Acebes
en
la
docencia
de
la
asignatura,
la
preparación
y
testado
de
materiales
y
en
la
revisión
crítica
de
este
documento
Positioning systems in Minkowski space-time: from emission to inertial coordinates
The coordinate transformation between emission coordinates and inertial
coordinates in Minkowski space-time is obtained for arbitrary configurations of
the emitters. It appears that a positioning system always generates two
different coordinate domains, namely, the front and the back emission
coordinate domains. For both domains, the corresponding covariant expression of
the transformation is explicitly given in terms of the emitter world-lines.
This task requires the notion of orientation of an emitter configuration. The
orientation is shown to be computable from the emission coordinates for the
users of a `central' region of the front emission coordinate domain. Other
space-time regions associated with the emission coordinates are also outlined.Comment: 20 pages; 1 figur
Influence of iron aggregation on the catalytic performance of desilicated MFI in the DeNO(x) process
[EN] In the present study, an influence of the iron aggregation in conventional and micro-mesoporous MFI on their catalytic activity in the NO reduction with ammonia (DeNO(x) process) was studied. Modification of MFI zeolite properties was done by the desilication in the presence of NaOH and TPAOH (tertapropylammonium hydroxide). In the next step, the samples were modified with iron by ion-exchange with the use of a conventional solution of Fe cations (FeSO4) and a solution of iron triple-metallic aggregates (oligocations) ([Fe-3(OAc)(6)O(H2O)(3)](+)). Both of the applied modification techniques (desilication and modification with Fe-3 oligocations) increased the catalytic activity of the MFI zeolite in the DeNO(x) process. This increased catalytic activity was connected with changes in sample porosity, Si/Al ratio, topology, as well as aggregation and dispersion of iron species on the catalyst surface, which was investigated by N-2-sorption, XRD, ICP, NMR, HRTEM and UV-vis-DRS techniques.This work was carried out in the frame of project No. 0670/IP3/2016/74 from the Polish Ministry of Science and Higher Education in the years 2016-2019 and in the frame of project No. 2012/05/B/ST5/00269 from the National Science Centre (Poland). U. D. acknowledges to the Spanish Government by the funding (MAT2017-82288-C2-1-P).Rutkowska, M.; Borcuch, A.; Marzec, A.; Kowalczyk, A.; Samojeden, B.; Moreno, J.; Díaz Morales, UM.... (2020). Influence of iron aggregation on the catalytic performance of desilicated MFI in the DeNO(x) process. Microporous and Mesoporous Materials. 304:1-8. https://doi.org/10.1016/j.micromeso.2018.09.015S1830
Landscape features influencing gene flow and connectivity ofan endangered passerine
Dispersal of individuals and gene flow are crucial aspects to maintain genetic diversity and viability of populations, especially in the case of threatened species. Landscape composition and structure may facilitate or limit individual movement within and among populations. We used a landscape genetics approach to assess the connectivity patterns of the threatened Dupont's lark (Chersophilus duponti subsp. duponti), considering their genetic patterns and the landscape features associated with its gene flow in Spain. We analysed the genetic relatedness based on 11 species-specific polymorphic microsatellites on 416 Dupont's lark individuals sampled across peninsular Spain between 2017 and 2019, covering most of the European distribution of the species. To assess the relationship between the landscape composition and the species gene flow, we estimated genetic distance at the individual level (Dps). Next, we built a set of environmental surfaces from two time periods (years 1990 and 2018), based on factors such as land use and topography, influencing individuals' movement. We then obtained resistance surfaces from an optimization process on landscape variables. Landscape genetics analyses were done for single and composite surface models for each year separately. Our findings from both time points show that scatter or mosaic-structured vegetation composed by low agricultural and tree cover and high presence of sclerophyllous shrubs favoured Dupont's lark dispersal, while dense and continuous tree cover, as well as areas of intensive agriculture, were limiting factors. Our results suggest the importance of steppe habitat patches for the species' establishment and dispersal. In addition, our results provide key information to develop conservation measures, including conserving and restoring steppe habitats as scattered and/or mosaic-structured vegetation that could warrant the connectivity and persistence of Dupont's lark populationsWe thank Julia G\u00F3mez-Catas\u00FAs, Margarita Reverter, Julia Zurdo, Israel Herv\u00E1s and all LIFE projects staff for their support in field and logistics work. We thank C. P\u00E9rez-Granados and G.M. L\u00F3pez-Iborra for sharing of Dupont's lark samples. We also thank the Instituto de Investigaci\u00F3n en Recursos Cineg\u00E9ticos, IREC (CSIC-UCLM-JCCM), who provided the laboratory facilities for DNA analysis. This work was approved by the Local Ethical Committee for Animal Experiments of the Universidad Aut\u00F3noma de Madrid (CEI80-1468-A229). All participants accepted to be part of the study. This study was supported by the European Commission (LIFE Ricot\u00ED project LIFE15-NAT-ES-000802 and LIFE Connect Ricot\u00ED project LIFE20-NAT-ES-000133) and the FPI-UAM fellowship from the Universidad Aut\u00F3noma de Madrid that supported D. Bustillo-de la Rosa. This paper contributes to project REMEDINAL TE-CM (P2018/EMT4338
Organophilic clays: characteristics, preparation methods, intercalation compounds and characterization techniques
As argilas são materiais muito usados e que atualmente apresentam inúmeras aplicações devido as interessantes propriedades que apresentam. A modificação superficial de argilas é uma área que tem recebido bastante atenção dos pesquisadores porque por meio dos diversos tipos de modificação é possível a preparação de novos materiais e novas aplicações. Este trabalho tem como objetivo apresentar uma revisão bibliográfica sobre argilas organofílicas, especialmente as obtidas a partir de bentonitas e de sais quaternários de amônio. Diversos estudos vêm sendo realizados baseados em diferentes técnicas e parâmetros de síntese desses materiais, incluindo argilas de diferentes regiões e diferentes agentes de modificação, bem como as diferentes aplicações que são propostas.Clays are materials used since historical periods and nowadays have several applications due to their interesting properties. The surface modification of clays is one area that has received enough attention from researchers because through modification it is possible to prepare new materials and find applications. The purpose of this paper is to present a review on the use of clays for obtaining organophilic clays, especially those used in polymeric nanocomposites. Several studies have been done based on different techniques and process conditions of these materials. The review includes clays of different regions, different modification agents and applications.54330213226CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQsem informaçã
Dietary niche overlap and resource partitioning among six steppe passerines of Central Spain using DNA metabarcoding
Trophic niche partitioning is a mechanism that facilitates the coexistence of ecologically similar species by sharing their resource use. However, detailed information of the trophic niche in insectivorous birds is usually limited by the lack of accurate identification of consumed food resources. The use of DNA metabarcoding has proved useful for molecular identification of the taxa present in bird faecal samples. Here, we used this molecular technique to study the diets of six steppe passerine species distributed in two Special Protection Areas in central Spain, and to characterize the dietary niche overlap and the prey composition differences between bird species. In total, we distinguished 112 diet items, covering 39 arthropod families of 13 orders. Although significant dietary differences existed in prey species composition, our results indicated a 74% overlap in steppe bird dietary niche, mostly due to high consumption of abundant arthropod prey such as beetles, grasshoppers and spiders in the breeding season by all bird species. The lowest overlap was found for the dietary niches of the Greater Short-toed Lark Calandrella brachydactyla and Dupont's Lark Chersophilus duponti, a scarce and threatened species, which appeared to be the species with the most distinct dietary niche within the community. Our results make a significant contribution to the knowledge of shrub-steppe bird diets and their trophic interactions, indicating that some extent of interspecific resource partitioning occurs in the study area, notably between Dupont's Lark and the Greater Short-toed Lark. Our study demonstrates the value of DNA metabarcoding in the assessment of passerine diets and provides useful ecological results for the design of biodiversity conservation programmes in the increasingly scarce and threatened steppe habitatsThis study was supported by the European Commission LIFE Ricot ı (LIFE15-NAT-ES-000802) and
LIFE Connect Ricot ı (LIFE20-NAT-ES-000133)
projects, and the BBVA Foundation Dron Ricot ı
project. This is a contribution to the Excellence
Network Remedinal 3CM (S2013/MAE2719). Lu ıs
P. da Silva and Vanessa A. Mata were funded by
Fundac ~ao para a Ci^encia e Tecnologia (FCT)
through the research contract CEECIND/02064/
2017 and 2020.02547.CEECIND, respectivel
Endogenous Biosynthesis of S-Nitrosoglutathione From Nitro-Fatty Acids in Plants
Nitro-fatty acids (NO2-FAs) are novel molecules resulting from the interaction of
unsaturated fatty acids and nitric oxide (NO) or NO-related molecules. In plants, it has
recently been described that NO2-FAs trigger an antioxidant and a defence response
against stressful situations. Among the properties of NO2-FAs highlight the ability to
release NO therefore modulating specific protein targets through post-translational
modifications (NO-PTMs). Thus, based on the capacity of NO2-FAs to act as
physiological NO donors and using high-accuracy mass-spectrometric approaches,
herein, we show that endogenous nitro-linolenic acid (NO2-Ln) can modulate S nitrosoglutathione (GSNO) biosynthesis in Arabidopsis. The incubation of NO2-Ln with
GSH was analyzed by LC-MS/MS and the in vitro synthesis of GSNO was noted. The in
vivo confirmation of this behavior was carried out by incubating Arabidopsis plants with
15N-labeled NO2-Ln throughout the roots, and 15N-labeled GSNO (GS15NO) was
detected in the leaves. With the aim to go in depth in the relation of NO2-FA and GSNO
in plants, Arabidopsis alkenal reductase mutants (aer mutants) which modulate NO2-FAs
levels were used. Our results constitute the first evidence of the modulation of a key NO
biological reservoir in plants (GSNO) by these novel NO2-FAs, increasing knowledge
about S-nitrosothiols and GSNO-signaling pathways in plants.This work was supported by an ERDF grant
cofinanced by the Ministry of Economy and Competitiveness
FIGURE 7 | Modulation of GSNO-signalling pathway by NO2-Ln in Arabidopsis leaves. NO2-Ln is up-taken by the root system and transported to plant leaves. Once in
these organs, NO2-Ln can release nitric oxide (NO) and mediate the S-nitrosation of abundant glutathione (GSH) present in plant leaves and leading to the formation of
S-nitrosoglutathione (GSNO). The generation of this low-molecular weight S-nitrosothiol (SNO) from NO2-Ln can affect the SNO-signaling pathway by modulating the
transport and storage of NO, the response to several (a)biotic stress conditions or mediating the ability of SNO to perform post-translational modifications.
Mata-Pe´ rez et al. Nitro-Fatty Acids Generates S-Nitrosogluthatione
Frontiers in Plant Science | www.frontiersin.org 10 June 2020 | Volume 11 | Article 962
(project PGC2018-096405-B-100), I+D+i Projects in the
framework of the Andalusia 2014-2020 ERDF Operational
Programme (Reference 1263509), Funding for the recruitment
of researchers under the Action 10 of the Research Support Plan
of the University of Jaén (2019-2020; R.02/10/2020) and the
Junta de Andalucía (group BIO286) in Spain. LC-MS/MS
technical and human support provided by CICT of
Universidad de Jaé n (UJA, MINECO, Junta de Andalućıa,
FEDER) is gratefully acknowledged
The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data
The use of IFS is since recently allowing to measure the emission line fluxes
of an increasingly large number of star-forming galaxies both locally and at
high redshift. The main goal of this study is to review the most widely used
empirical oxygen calibrations, O3N2 and N2, by using new direct abundance
measurements. We pay special attention to the expected uncertainty of these
calibrations as a function of the index value or abundance derived and the
presence of possible systematic offsets. This is possible thanks to the
analysis of the most ambitious compilation of Te-based HII regions to date.
This new dataset compiles the Te-based abundances of 603 HII regions extracted
from the literature but also includes new measurements from the CALIFA survey.
Besides providing new and improved empirical calibrations for the gas
abundance, we also present here a comparison between our revisited calibrations
with a total of 3423 additional CALIFA HII complexes with abundances derived
using the ONS calibration by Pilyugin et al. (2010). The combined analysis of
Te-based and ONS abundances allows us to derive their most accurate calibration
to date for both the O3N2 and N2 single-ratio indicators, in terms of all
statistical significance, quality and coverage of the space of parameters. In
particular, we infer that these indicators show shallower abundance
dependencies and statistically-significant offsets compared to those of Pettini
and Pagel (2004), Nagao et al. (2006) and P\'erez-Montero and Contini (2009).
The O3N2 and N2 indicators can be empirically applied to derive oxygen
abundances calibrations from either direct abundance determinations with random
errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a
large amount of data) reaching an average precision of 0.08 and 0.09 dex
(random) and 0.02 and 0.08 dex (systematic; compared to the direct
estimations),respectively.Comment: 12 pages, 5 figures, accepted for publication in A&
Protect European green agricultural policies for future food security
Instituto de Ciencias Forestales (ICIFOR-INIA).European green agricultural policies have been relaxed to allow cultivation of fallow land to produce animal feed and meet shortfalls in exports from Ukraine and Russia. However, conversion of semi-natural habitats will disproportionately impact long term biodiversity and food security.This paper contributes to project REMEDINAL TE-CM P2018/EMT-4338 of Comunidad de Madrid.Peer reviewe
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