Effect of grazing abandonment on the function and plant diversity of atlantic mountain grasslands

166 p.(eng);120 p.(eus)Doktore-tesi honek, larratze misto estentsiboaren uzteak dituen ondorioak aztertu ditu Aralar NaturParkeko mendiko larre emankorretan, Euskal Herrian. Herbiboroen larratzea esperimentalki ekiditeko 50× 50 m2-ko lau itxitura eraiki ziren. Larratze-gune bana ezarri zen esklusio-gune bakoitzaren ondoan, nonherbiboroek libreki bazkatzen duten landare-hazkuntza sasoian zehar. Hasteko larratzeari uzteareneragina aztertu zen lurzoruko elikagaien zikloan eta mineralizazioan. Larratzeak larreko elikagaienzikloari eragin zion bazkaren kalitatea hobetuz, eta lurzoruko tenperatura-erregimena zein lurzoruko uredukiaaldaraziz. Ondoren, larratzearen eragina aztertu zen landare-komunitatearen egituran eta landaredibertsitatean.10 urteko larratze-esklusioaren ondoren, hau da, aurrez zegoen mekanismo ekualizatzailesendoa epe luzez kendu ondoren, espezie lehiakorrek multzokapen espazial handiak sortu zituzten etalehiaz espezie ahulagoak kanporatu zituzten, horrela landare-dibertsitatea jaitsiz.Lehiazko esklusionabarmena gertatzen da larre emankorretan, nitxo-egonkortzea ahula izaten delako (baliagaietanaberatsak baitira). Nitxo-egonkortze kontrajarriak dituzten bi gune esperimental erabiliz, nitxoegonkortzeaklehiazko esklusioari egiten dion kontrako indarra aztertu zen. Nitxo-egonkortze ahularekin,lehiatze-gaitasun altuko gramineoen nagusitasunak galera handia eragin zuen dibertsitate filogenetikoan.Aldiz, nitxo-egonkortze ertain-sendoak lehiazko esklusioa ahuldu egin zuen eta, ondorioz, galeratxikiagoa izan zen dibertsitate filogenetikoan. Tesiaren ondorio nagusia da ganadu mistoak eginikolarratze tradizionala funtsezko faktore ekologikoa dela larre atlantikoen funtzionamendua eta landaredibertsitateamantentzeko

Floristic Composition Mediates Change in Forage Nutritive Quality of Atlantic Mountain Grasslands after Experimental Grazing Exclusion

Simultaneous reduction of biodiversity and forage nutritive value after grazing abandonment represents a critical agroecological problem observed in temperate mountain grasslands. However, how both processes affect each other after the exclusion of large grazers is not well understood. To address this knowledge gap, we used four Atlantic grassland sites in the Aralar masif (northern Iberian Peninsula) to ask whether floristic composition mediates change in forage nutritive quality after grazing exclusion, and, if so, how much of the effect on forage quality is mediated. To examine the effects of grazing exclusion on forage quality and floristic composition a repeated-measures (2005–10) randomized complete block experiment was used. Then, the direct effects of grazing exclusion on forage quality were disentangled from the indirect effects mediated by concurrent change in floristic composition. Grazing exclusion deteriorated forage mineral content, phosphorus content, neutral detergent fiber and, especially, crude protein and enzymatic digestibility. Concurrent floristic change mediated change in crude protein (80%), enzymatic digestibility (55%) and forage content in calcium (31%). Our study shows that plant diversity and forage quality are intimately linked features of Atlantic mountain grasslands and highlights the importance of preserving leguminous and dicotyledonous species to maintain the nutritive value of these grasslands.This research was funded by the Basque Government—Eusko Jaurlaritza—(grant numbers: ETORTEK10/34, IT1022-16), by the UNESCO Cathedra of the University of the Basque Country—UPV/EHU—(grant number: UNESCO07/07), and by the Ministry of Economy and Competitiveness of the Spanish Government (grant number: AGL2013-48361-C2-1-R)

Possible relationship between the gut leaky syndrome and musculoskeletal injuries: the important role of gut microbiota as indirect modulator

This article aims to examine the evidence on the relationship between gut microbiota (GM), leaky gut syndrome and musculoskeletal injuries. Musculoskeletal injuries can significantly impair athletic performance, overall health, and quality of life. Emerging evidence suggests that the state of the gut microbiota and the functional intestinal permeability may contribute to injury recovery. Since 2007, a growing field of research has supported the idea that GM exerts an essential role maintaining intestinal homeostasis and organic and systemic health. Leaky gut syndrome is an acquired condition where the intestinal permeability is impaired, and different bacteria and/or toxins enter in the bloodstream, thereby promoting systemic endotoxemia and chronic low-grade inflammation. This systemic condition could indirectly contribute to increased local musculoskeletal inflammation and chronificate injuries and pain, thereby reducing recovery-time and limiting sport performance. Different strategies, including a healthy diet and the intake of pre/probiotics, may contribute to improving and/or restoring gut health, thereby modulating both systemically as local inflammation and pain. Here, we sought to identify critical factors and potential strategies that could positively improve gut microbiota and intestinal health, and reduce the risk of musculoskeletal injuries and its recovery-time and pain. In conclusion, recent evidences indicate that improving gut health has indirect consequences on the musculoskeletal tissue homeostasis and recovery through the direct modulation of systemic inflammation, the immune response and the nociceptive pain

Photosynthesis is not the unique useful trait for discriminating salt tolerance capacity between sensitive and tolerant quinoa varieties

Main conclusion Growth was not strictly linked to photosynthesis performance under salinity conditions in quinoa. Other key traits, which were varieties-specific, rather than photosynthesis explained better growth performance. Phenotyping for salinity stress tolerance in quinoa is of great interest to select traits contributing to overall salinity tolerance and to understand the response mechanisms to salinity at a whole plant level. The objective of this work was to dissect the responses of specific traits and analyse relations between these traits to better understand growth response under salinity conditions in quinoa. Growth response to salinity was mostly related to differences in basal values of biomass, being reduced the most in plants with higher basal biomass. Regarding the relationship between growth and specific traits, in Puno variety, better photosynthetic performance was related to a better maintenance of growth. Nevertheless, in the rest of the varieties other traits rather than photosynthesis could better explain growth response. In this way, the development of succulence in F-16 and Collana varieties, also the osmotic adjustment but in smaller dimensions in Pasankalla, Marisma and S-15-15 helped to maintain better growth. Besides, smaller increases of Cl- could have caused a limited nitrate uptake reducing more growth in Vikinga. Ascorbate was considered a key trait as a noticeable fall of it was also related to higher reductions in growth in Titicaca. These results suggest that, due to the genetic variability of quinoa and the complexity of salinity tolerance, no unique and specific traits should be taken into consideration when using phenotyping for analysing salinity tolerance in quinoa.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature

Variation in the Climate Sensitivity Dependent on Neighbourhood Composition in a Secondary Mixed Forest

Understanding the vulnerability of individual trees to climate requires moving from population to individual level. This study evaluates individual tree response in a mixed forest by assessing how size and neighbourhood density modulated growth responses to climate among coexisting tree species. To understand the complete variation in growth responses to climate, it is necessary to consider intrapopulation variability. Trees respond as individual entities, and their response is modulated by their characteristics and neighbourhood context. To assess the individual climate sensitivity, all living Iberian birches, European beeches, and pedunculate oaks trees located in a temperate mixed forest were cored in four 40 m × 40 m plots. Standard ring-width chronologies were built at tree and species level for the 1977–2007 period. Chronologies were related to climatic variables (monthly precipitation, hailstorm and mean temperature, and summer (June–August) precipitation). Growth response to climate varied among species and individual trees. Differences in climate–growth relationship among species could be partially attributed to the different xylem anatomy, since secondary growth of ring-porous pedunculate oak (Quercus robur L.) was mainly dependent on the previous-winter climatic conditions (January temperature), while for the diffuse-porous Iberian birch (Betula celtiberica Rothm. and Vasc.) and European beech (Fagus sylvatica L.), spring temperature and summer precipitation were the major constraining factors of growth. Tree features and identity of neighbourhood modulated climatic response, especially for Iberian birch and pedunculate oak. Dominant trees in less crowded neighbourhoods responded more intensely to climate factors. Understanding the individual variability of growth responses to climate will provide more realistic predictions of forests response to climate change.Special thanks to Silvia Martinez de Olcoz for assistance with the fieldwork and the measurements of the tree-rings. Urkiola Natural Park provided the facilities for field work. Urkiola Natural Park provided the facilities for field work and financial support. Additional financial support was provided by a Basque Government (Grupo de Investigacion Consolidado: Grupo Estudio en Flora, Vegetacion y Ecosistemas Terrestres). Furthermore, this work has been supported by the projects CGL2012-34209 and CGL2015-69186-C2-1-R (Spanish Ministry of Economy and Competitivity) and by the Excellence Network "Ecometas" (CGL2014-53840-REDT)

El abandono del pastoreo afecta negativamente a la calidad del pasto en pastizales atlánticos ibéricos

Forage quality in mountain grasslands is an important factor for maintaining or improving animal performance. Previous studies identified plant traits beneficial for animal nutrition; however, little is known regarding their maintenance in plant communities. Our main hypothesis was that grazing favors plants with high regrowth capacity and low resource utilization efficiency, promoting the production of high-quality forage. To test the hypothesis, we conducted a grazer exclusion experiment in an Iberian Atlantic grassland combined with a response-effect framework based on various plant traits and an appropriate statistical methodology to measure the relative contribution of species turnover and intraspecific trait variability (ITV) after grazing abandonment. Our results showed that forage quality declined after short-term grazing abandonment, via strong ITV effects and weak species turnover effects. Strong species turnover effects might appear after longer period of abandonment if, as expected, tall grasses with low tissue quality outcompete species with high tissue quality.La calidad del pasto en los pastizales de montaña es un factor importante para mantener o mejorar el rendimiento animal. Estudios previos han identificado atributos vegetales beneficiosos para la nutrición animal; sin embargo, poco se sabe sobre su mantenimiento en comunidades vegetales. Nuestra principal hipótesis sostiene que el pastoreo favorece a las especies con una alta capacidad de rebrote y una baja eficiencia de utilización de recursos, promoviendo así la producción de pasto de alta calidad. Para testar la hipótesis, realizamos un experimento de exclusión del pastoreo en un pastizal de la montaña atlántica, combinado con un marco teórico de respuesta-efecto basado en varios atributos vegetales y una metodología estadística apropiada para medir la contribución relativa del recambio de especies y la variabilidad intraespecífica de los atributos (ITV) tras el abandono del pastoreo. Nuestros resultados mostraron que la calidad del pasto disminuyó tras el abandono del pastoreo a corto plazo, principalmente debido al efecto de la ITV. Los efectos por recambio de especies podrían aparecer tras un período más largo de abandono si, tal y como es esperable, las gramíneas altas con tejidos de baja calidad nutritiva sustituyen a las especies de mayor calidad

Dehydration and rehydration differently affect photosynthesis and volatile monoterpenes in bryophytes with contrasting ecological traits

Bryophytes desiccate rapidly when relative humidity decreases. The capacity to withstand dehydration depends on several ecological and physiological factors. Volatile organic compounds (VOCs) may have a role in enhancing tolerance to desiccating bryophytes. However, the functions of VOCs in bryophytes have received little attention so far. We aimed to investigate the impact of a dehydration-rehydration treatment on primary carbon metabolism and volatile terpenes (VTs) in three bryophytes with contrasting ecological traits: Vessicularia dubyana, Porella platyphylla and Pleurochaete squarrosa. First, we confirmed the desiccation sensitivity gradient of the species. Under fully hydrated conditions, the photosynthetic rate (A) was inversely associated with stress tolerance, with a lower rate in more tolerant species. The partial recovery of A in P. platyphylla and P. squarrosa after rehydration confirmed the desiccation tolerance of these two species. On the other hand, A did not recover after rehydration in V. dubyana. Regarding VT, each species exhibited a distinct VT profile under optimum hydration, with the highest VT pool found in the more desiccation-sensitive species (V. dubyana). However, the observed species-specific VT pattern could be associated with the ecological habitat of each species. P. squarrosa, a moss of dry habitats, may synthesize mainly non-volatile secondary metabolites as stress-defensive compounds. On the other hand, V. dubyana, commonly found submerged, may need to invest photosynthetically assimilated carbon to synthesize a higher amount of VTs to cope with transient water stress occurrence. Further research on the functions of VTs in bryophytes is needed to deepen our understanding of their ecological significance.This work was supported by the Basque Government (UPV/EHU IT-1648-22); PID2020-113244GA-C22 (funded by MCIN/ AEI /10.13039/501100011033); PGC2018-093824-B-C44 funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF “A way of making Europe”. RE received a “Juan de la Cierva-Incorporation” Fellowship IJCI-2014-21452 and a “José Castillejo” mobility grant CAS17/00146

Euskarazko hitz anitzeko unitate lexikalen tratamendu konputazionala

Multi-word Lexical Units (MWLU) are of great importance in language in general, and in Natural Language Processing in particular, since they are not governed by the free rules of the system. In this article, we give an overview of the different types of phraseological units, explaining briefly each one's features. Our priority being to process idioms automatically in Basque texts, we concisely analyze several approaches for the inflectional description of MWLUs, and then, we explain the system we have developed for Basque: (i) a general representation for describing MWLUs in the lexical database for Basque (EDBL), (ii) HABIL, a tool capable of detecting and analyzing them based on the features described in the database, and (iii) a constraint grammar for disambiguating ambiguous MWLUs

Euskarazko hitz anitzeko unitate lexikalen tratamendu konputazionala

Multi-word Lexical Units (MWLU) are of great importance in language in general, and in Natural Language Processing in particular, since they are not governed by the free rules of the system. In this article, we give an overview of the different types of phraseological units, explaining briefly each one's features. Our priority being to process idioms automatically in Basque texts, we concisely analyze several approaches for the inflectional description of MWLUs, and then, we explain the system we have developed for Basque: (i) a general representation for describing MWLUs in the lexical database for Basque (EDBL), (ii) HABIL, a tool capable of detecting and analyzing them based on the features described in the database, and (iii) a constraint grammar for disambiguating ambiguous MWLUs