2,059 research outputs found

    Jeweled spider flies (Eulonchus Tristis) are important pollinators of Iris Bracteata, a rare Siskiyou Mountain endemic

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    Little is known about the pollination biology of the Pacific Coast Irises (Iris: series Californicae, hereafter PCI), especially who visits and pollinates their flowers. In general, Iris flowers are considered bee-pollinated, however, flies in the genus Eulonchus (Acroceridae) are known to visit some PCI members. Therefore, I assessed the relative importance of Eulonchus and other insect visitors to the pollination of a rare PCI species native to the Siskiyou Mountains, I. bracteata. Methods. I quantified pollinator importance for all flower visitors at sites in northern California and southern Oregon as the product of average visit rate and the probability of stigma contact. I also documented the flower-handling behaviors of each visitor and determined the average number of grains delivered to virgin stigmas by the most frequent flower visitor. Key results. A diverse set of insects visited the flowers of I. bracteata. Their visitation rates, flower-handling behaviors, and probability of contacting stigmas differed substantially. Contrary to expectations, the fly E. tristis was the most important pollinator; it accounted for more than 70% of total visits and consistently contacted stigmas when entering flowers. The species delivered an average of 185 grains per visit (median=96), which exceeds the average number of ovules per flower (100). Some bees (Osmia densa, Bombus vosnesenskii) likewise contacted stigmas and thus are potential pollinators, but they seldom visited flowers at my study sites. Implications. My findings contribute to our general understanding of the role that flies play in pollination. Specifically, they show that flies in the genus Eulonchus – and not bees – are the main pollinators of a rare Iris in northern California and southern Oregon. Resource managers concerned about the conservation status of the plant should consider the life history requirements of the flies and, especially, the vulnerability of their larval spider hosts to habitat alteration. Several other plants in the same region are known to be visited by Eulonchus and thus, additional studies assessing their importance as pollinators are warranted

    Vulnerability and resilience to drought in the Chaco, Paraguay

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    This chapter presents an innovative methodology to identify and characterise the vulnerability and resilience to drought in ten indigenous communities (comunidad) in Chaco, Paraguay. The first part studies meteorological drought through the analysis of average daily rainfall over the last 38 years. The second part analyses vulnerability (V) on the comunidad scale. The third and final part analyses resilience (R) on the comunidad scale. The main sources used are the survey conducted for the Participatory community diagnosis (2014), from which 18 indicators have been chosen to measure exposure (E), sensitivity (S), and adaptive capacity (Ac) according to the equation V = (E * S) / Ac. We ascertain that rainfall in the driest areas of the Paraguayan Chaco varies cyclically in relation to the meteorological phenomena of El Niño and La Niña. The operative consequence of this phenomenon is that in the Chaco, drought may be predicted with enough forewarning to launch an early warning in the driest areas. Furthermore, we highlight that the most vulnerable comunidades are also the most resilient. This demonstrates that the various projects undertaken to strengthen resilience have so far benefited the most vulnerable communities and therefore the drought defence has been well directed

    a short introduction

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    UID/CPO/04627/2013Globalization is one of the most important social phenomena in the contemporary world, shaping all dimensions of societal life. However, both among globalization theory as well as foreign policy (FP) studies (and FPA, in particular), the impact of globalization on the state, the effects of political globalization and the transformations it brings to FP have been understood as (not so relevant) contextual elements, described in a generic way or even completely excluded from those research fields and interests. Nevertheless, the particular characteristics in which FP activities are developed render essential, rather than ignoring the state and its external action, to strengthen its study seeking to assess the scope, nature and impact of globalization on its international activity. Following a brief overview on the interaction between globalization theory and FP, as well as between FP studies and globalization, we will explore the analysis model, analysing these challenges on two different levels. Firstly, the impact of globalization in FP: the higher relevance of multilateral or bilateral relations; the identification of certain problems (threats/risks) as global, and requiring a global response; and (growing?) influence/involvement of other actors in the decision in FP at the national level. Secondly, the greater role played by global governance (GG) in FP issues: to identify the (growing?) influence/involvement of other actors in the implementation of FP, or decision in GG structures; the influence of multiple levels of governance in FP; an increase in temporary coalitions, and greater adaptation to the international environment; and shaping GG structures as a FP goal. We are particularly interested in the characteristics and implications of some core prerogatives of our theoretical framework, as well as the limitations and possible solutions to the challenges that studying globalization and the contemporary foreign policy of Southern European countries poses. Our claim is that FP studies could be rendered more valuable and specific if they adapt to include globalization in its studies as a relevant variable, particularly if they do so in a systematic and comparative fashion.publishersversionpublishe

    the cases of Portugal and Spain

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    UID/CPO/04627/2013publishersversionpublishe

    A New Method for the Improvement of Data

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    Introduction – The use of the average analytical signal for the construction of curves by the least squares method (LSM) over the standard addition method (SAM) is widespread. It would be advantageous, however, to fi nd a way to avoid intermediary averages, which are known to be the cause of signifi cant increases in standard deviations (SD). Objective – To develop a protocol that uses all gathered data to create curves by LSM over SAM. To use Excel® for the estimation of y = mx + b and R2 rather than using LSM equations for the SD of m, x and b. Methodology – The level of lead (II) in the bark (cork) of Quercus suber Linnaeus was determined using diff erential pulse anodic stripping voltammetry (DPASV). Three current samples were taken for each of the four standard additions. These signals were combined for adjustment by LSM. The results were compared with those obtained after averaging the current for each addition, and the expression of uncertainty in the measurements determined. Results – The new method shows an expanded uncertainty of ± 0.3321 μg/g (nearly 1.42%). The diff erence between the results obtained by the new and the old method is 0.01 μg/g (23.41 and 23.40 μg/g). The limit of detection changed approximately from 4.8 to 4 μg/g and the relative SD approximately from 9 to 6%. Conclusion – The absence of intermediary averages in curves improved the determination of lead (II) in cork by DPASV. Estimation of SD only with LSM equations produced results that were signifi cantly worse. The changes are large enough to transform an apparently internally non-validated procedure (repeatability for precision) into an internally validated procedure

    Update: Outbreak prediction for Asian soybean rust in Iowa

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    Last year, Asian soybean rust moved slowly and did not show up in Iowa. Because of the dry weather conditions that prevailed during the 2005 growing season, one cannot draw a meaningful conclusion. Therefore, soybean rust remains a major concern for soybean producers in the northern regions. A common question asked this winter has been: what is the risk of a soybean rust outbreak in the upcoming season

    Lawns and ornamental meadows as an alternative in the South Europe

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    In the south of Europe, namely in Portugal or Spain, lawns invaded the gardens. Historically, lawns did not belong to the mediterranean garden, but, by anglo-normand influence the turfgrass is now used everywhere (Filippi, 2011). We expect that plants can help us to solve our ecological, technical or social problems. However, the use of plants can bring us some problems too. The use of plants in urban spaces is extremely social and cultural conditioned especially if we think about naturalistic plantings (Hitchmough & Dunnet, 2004). Lawns are an idyllic green soil cover very desired by general public in the Mediterranean climate. But the energy and water necessary to maintain a lawn in Mediterranean conditions is very expensive, economically and ecologically unsustainable. Ornamental meadows are an alternative that has qualities to substitute lawns in extensive framing areas in urban space. It is a very sustainable and biodiverse alternative that is already being used in many cities (Gilsoul, 2011). Ornamental meadows can help us to create more sustainable, diverse and interesting green spaces. Plants with interesting flowers can be used in ornamental meadows and create a spectacular blooming season. In this work we proposed to study the way Landscape Architects choice to use lawns or ornamental meadows in a Mediterranean climate were water to irrigate is a limit factor. How they are influenced by themes like sustainability, ecology or biodiversity, or conditioned by political or social opinions in their design of urban green spaces, were questions explored. The methodology used was surveys directed to active Landscape Architects designers that work in the South of Europe in a Mediterranean climate. Questions about what influences their choices when they have to choose between using lawns or ornamental meadows were asked. This theme was explored in order to understand what conditions the use of lawns or ornamental meadows at the designing level. With this work we hope to contribute to the knowledge about the use of plants covertures in cities in the South Europe
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