10,436 research outputs found

    Revisão taxonómica do género Calendula L. (Asteraceae - Calenduleae) na Península Ibérica e Marrocos

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    The genus Calendula L. (Asteraceae - Calenduleae) includes, depending on the author, 10 to 25 species, distributed mainly in the Mediterranean basin. The taxonomy of this genus is considered to be extremely difficult, due to a great morphological variability, doubtfull relevance of some of the characters used to distinguish its species (e.g. the life form: annual or perennial; the habit: erect or diffuse, shape of the leaves, indumentum, relative size of the capitula and colour of disc or ray florets, achene morphology), but also due to the hybridization and polyploidization. Despite the numerous studies that have been published, no agreement on the classification and characters used to discriminate between taxa has been reached. A taxonomic study of the genus Calendula was conducted for the Iberian Peninsula and Morocco, aiming at (1) access the morphological variability between and within taxa, (2) confirm the chromosome numbers, (3) increase the nuclear DNA content estimations, (4) re-evaluate taxa delimitations and circumscription, and (5) reassess, and redefine, the descriptions and characters useful to distinguish taxa. In order to achieve a satisfying taxonomic core, extensive fieldwork, detailed morphometric analysis, chorological, karyological and genome size studies were conducted. For the Iberian Peninsula, four species were recognized, including nine subspecies (between these two new subspecies were described). For Morocco, including some taxa from Algeria and Tunisia 13 species were recognized (two new species and a nomenclatural change), including 15 subspecies (among these eight new subspecies were described). To corroborate the results obtained and to evaluate the evolutionary relationships among taxa, phylogenetic studies using molecular methods, such as ITS, microsatellites or other molecular markers, should be used.O gĂ©nero Calendula L. (Asteraceae - Calenduleae) inclui, dependendo do autor, 10 a 25 espĂ©cies, distribuĂ­das essencialmente na bacia do MediterrĂąneo. A taxonomia deste gĂ©nero Ă© considerada extremamente difĂ­cil, devido Ă  grande variabilidade morfolĂłgica, discutivel relevĂąncia de alguns dos caracteres utilizados para distinguir suas espĂ©cies (por exemplo, a forma de vida: anual ou perene, o hĂĄbito: erecto ou difuso, a forma das folhas, o indumento, o tamanho e a cor dos capĂ­tulos e a morfologia dos aquĂ©nios), mas tambĂ©m devido Ă  hibridização e poliploidização. Apesar dos inĂșmeros estudos que foram publicados, nĂŁo foi alcançado um acordo sobre a classificação e os caracteres utilizados para discriminar as suas espĂ©cies. Um estudo taxonĂłmico do gĂ©nero Calendula foi realizado para a PenĂ­nsula IbĂ©rica e Marrocos, com o objectivo de (1) verificar a variabilidade morfolĂłgica, (2) confirmar o nĂșmero de cromossomas, (3) aumentar as estimativas de conteĂșdo em ADN, (4) reavaliar a delimitação e a circunscrição dos taxa, e (5) reavaliar e redefinir as descriçÔes e caracteres Ășteis para os distinguir. Para alcançar uma robustĂȘs taxonĂłmica satisfatĂłria, foram realizados extensos trabalhos de campo, anĂĄlise morfomĂ©trica detalhada, abordagens corolĂłgicas, cariolĂłgicas e quanto ao conteĂșdo em ADN. Para a PenĂ­nsula IbĂ©rica, quatro espĂ©cies foram reconhecidas, incluindo nove subespĂ©cies (entre essas duas novas subespĂ©cies foram descritas). Para Marrocos, incluindo alguns taxa da Argelia e Tunisia, foram reconhecidas 13 espĂ©cies (duas novas e uma mudança nomenclatural), incluindo 15 subespĂ©cies (entre essas oito novas subespĂ©cies foram descritas). Para corroborar os resultados obtidos e avaliar as relaçÔes evolutivas e filogenĂ©ticas entre os taxa, estudos que utilizem diferentes mĂ©todos moleculares, tais como ITS, microsatĂ©lites ou outros marcadores moleculares, devem ser utilizados.Apoio financeiro do LaboratĂłrio Associado CESAM - Centro de Estudos do Ambiente e do Mar (AMB/50017) financiado por fundos nacionais atravĂ©s da FCT/MCTES e cofinanciado pelo FEDER (POCI-01-0145-FEDER-007638), no Ăąmbito do Acordo de Parceria PT2020, e Compete 2020Programa Doutoral em Biologi

    Desire, marriage, and overpopulation: The sexual lives of insects in the Enlightenment

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    This is the final version. Available from Brill Academic Publishers via the DOI in this record. During the eighteenth century, the discovery of sexual reproduction in insect species prompted the demise of spontaneous generation and new developments in natural history, theology, and political economy. The sexual lives of insects prompted debates on whether insects were governed by desire, free will, and even marital tendency. Fuelled by the democratisation of microscopy, early modern entomology took a new turn and breadth: the study of insects and of their sexual lives provided unexpected new insights into human sexuality, reproduction, and Malthusian fears of overpopulation. This article surveys the intellectual culture of entomology and natural history during the crucial decades when entomologists worked to quantify the reproductive capacities of insect species. Assessing the influences these entomological works had within political economy and theology, we argue that the sexual lives of insects − once analysed and delineated − influenced familiar ideological features of the intellectual landscape of the late Enlightenment, particularly in the theological philosophies of northern Europe and in the political economy of population in Britain

    A global fuel characteristic model and dataset for wildfire prediction

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    Effective wildfire management and prevention strategies depend on accurate forecasts of fire occurrence and propagation. Fuel load and fuel moisture content are essential variables for forecasting fire occurrence, and whilst existing operational systems incorporate dead fuel moisture content, both live fuel moisture content and fuel load are either approximated or neglected. We propose a mid-complexity model combining data driven and analytical methods to predict fuel characteristics. The model can be integrated into earth system models to provide real-time forecasts and climate records taking advantage of meteorological variables, land surface modelling, and satellite observations. Fuel load and moisture is partitioned into live and dead fuels, including both wood and foliage components. As an example, we have generated a 10-year dataset which is well correlated with independent data and largely explains observed fire activity globally. While dead fuel moisture correlates highest with fire activity, live fuel moisture and load are shown to potentially enhance prediction skill. The use of observation data to inform a dynamical model is a crucial first step toward disentangling the contributing factors of fuel and weather to understand fire evolution globally. This dataset, with high spatiotemporal resolution (∌9 km, daily), is the first of its kind and will be regularly updated.</p

    Dynamics of desertification of arid ecosystems of Kizlyar pastures

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    The authors conducted research to identify the sources of formation of sand massifs, which then become the main cause of desertification of the territories of Kizlyar pastures, in order to carry out protective measures. In the article, the authors present materials confirming desertification and its ecological aspects. The ecological state of arid territories of Russia is one of the most acute problems that requires constant monitoring. Global changes in climatic conditions have a significant impact on the functioning of terrestrial ecosystems, including the soil cover. With the warming of the climate, the development of the processes of wind erosion and soil salinization increases. As a result, the pastures of Kizlyar were driven into extreme conditions. Pastures have come to an extremely critical state, and the degree of degradation of damage caused by these processes is much higher than other regions of the European South of Russia. The ecological situation of the territory is deteriorating rapidly. According to various estimates, large areas of them are occupied by open sands – 60.0 - 71.3 thousand hectares. As the analysis of the experience of the work carried out on the Kizlyar pastures shows, their effectiveness was extremely low, and in some places they contributed to the strengthening of the development of natural degradation processes. As a result, destabilizing factors have emerged that ensure the production of established phytocenoses, worsening conditions and progressing every year. At present, there are practically no improved pasture lands with natural vegetation in the Tersk-Kum lowland. In the current situation, the priority is to stop the activity of moving sands, as well as to improve the state of the species diversity of vegetation, otherwise, if these processes continue at the same pace, it may endanger the very existence of pastures and the basis of life in this territory

    Urbanised forested landscape: Urbanisation, timber extraction and forest care on the Vișeu Valley, northern Romania

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    By looking at urbanisation processes from the vantage point of the forest, and the ways in which it both constitutes our living space while having been separated from the bounded space of the urban in modern history, the thesis asks: How can we (re)imagine urbanisation beyond the limits of the urban? How can a feminine line of thinking engage with the forest beyond the capitalist-colonial paradigm and its extractive project? and How can we “think with care” (Puig de la Bellacasa 2017) towards the forest as an inhabitant of our common world, instead of perpetuating the image of the forest as a space outside the delimited boundaries of the city? Through a case study research, introducing the Vișeu Valley in northern Romania as both a site engaged in the circulation of the global timber flow, a part of what Brenner and Schmid (2014) name “planetary urbanisation”, where the extractive logging operations beginning in the late XVIIIth century have constructed it as an extractive landscape, and a more than human landscape inhabited by a multitude of beings (animal, plant, and human) the thesis argues towards the importance of forest care and indigenous knowledge in landscape management understood as a trans-generational transmission of knowledge, that is interdependent with the persistence of the landscape as such. Having a trans-scalar approach, the thesis investigates the ways in which the extractive projects of the capitalist-colonial paradigm have and still are shaping forested landscapes across the globe in order to situate the case as part of a planetary forest landscape and the contemporary debates it is engaged in. By engaging with emerging paradigms within the fields of plant communication, forestry, legal scholarship and landscape urbanism that present trees and forests as intelligent beings, and look at urbanisation as a way of inhabiting the landscape in both indigenous and modern cultures, the thesis argues towards viewing forested landscapes as more than human living spaces. Thinking urbanisation through the case of the Vișeu Valley’s urbanised forested landscape, the thesis aligns with alternate ways of viewing urbanisation as co-habitation with more than human beings, particularly those emerging from interdisciplinary research in the Amazon river basin (Tavares 2017, Heckenberger 2012) and, in light of emerging discourses on the rights of nature, proposes an expanded concept of planetary citizenship, to include non-human personhood

    On farm and off-farm feed utilization and improved management options: A Synthesis

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    The challenges identified in the proposal of the CGIAR Research Program (CRP) on Livestock, for enhancing livestock production and productivity, have been the shortage of quality feeds, inefficient utilization of feed resources, degradation of rangelands, and lack of knowledge and skills of stakeholders in the feed production and utilization value chains. To address these challenges, the research and development work, innovations developed and tested, results-dissemination and concerted efforts towards capacity building have been presented in the following three main sections. 1) Enlarging the feed quality resource base 2) Efficient use of feed resources 3) Rehabilitation of degraded rangeland

    System Dynamics Tools to Study Mediterranean Rangeland’s Sustainability

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    Rangelands are a key resource present all over the world and cover half of all emerged lands. They are even more important in drylands, where they cover 48% of the total area. Their intensification and the additional pressure added by climate change push these socio-ecological systems towards desertification. Over the last two decades, we have developed and applied System Dynamics (SD) models for the study of Mediterranean grasslands. In addition, we have designed procedures and analysis tools, such as global sensitivity analysis, stability analysis condition, or risk analysis, to detect the main drivers of these socio-ecological systems and provide indicators about their long-term sustainability. This paper reviews these works, their scientific background, and the most relevant conclusions, including purely technical and rangeland-related ones, as well as our experience as systemic modelers in a world driven by field specialists.This research was funded by DeSurvey (CE-Integrated Project Contract No. 003950), PADEG (CGL2008/01215/BTE), and BIODESERT (European Research Council grant agreement No. 647038)

    Sustainable agricultural management of saline soils in arid and semi-arid Mediterranean regions through halophytes, microbial and soil-based technologies

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    Soil salinization is an important global issue since marginal salt-affected soils have harmful consequences in agriculture and ecosystems. This article reviews different sustainable strategies adopted for marginal soil reclamation in Mediterranean climates. An innovative approach to soil salinity management includes a wide range of technologies, such as: phytoremediation, phytodesalination, vegetative bioremediation, amendments application and Technosols as well as inoculation with beneficial microorganisms like plant growth promoting bacteria and arbuscular mycorrhizal fungi. Besides that, the role of Mediterranean halophyte crops in acceler- ating salt-affected area’s recovery while providing food and feed, and beneficial halophilic microorganisms for new bioinoculant production, are discussed. We conclude that the combined use of plant, soil- and microbial- based technologies is a valuable option to relieve saline stress exposure and improve crops growth and yield in saline conditions.Federation of European Microbiological Societies (FEMS) (FEMS-GO-2020- 203),) (FEMS-GO-2020–203 University), University of Sevilla (Spain; Plan Propio de Investigación y Tranferencia 2021 Ayuda A1-I.3A1)info:eu-repo/semantics/publishedVersio
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