229 research outputs found

    Effects of experimental warming at the microhabitat scale on oak leaf traits and insect herbivory across a contrasting environmental gradient

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    Forest microclimatic variation can result in substantial temperature differences at local scales with concomitant impacts on plant defences and herbivory. Such microclimatic effects, however, may differ across abiotically contrasting sites depending on background environmental differences. To test these cross-scale effects shaping species ecological and evolutionary responses, we experimentally tested the effects of aboveground microhabitat warming on insect leaf herbivory and leaf defences (toughness, phenolic compounds) for saplings of sessile oak Quercus petraea across two abiotically contrasting sites spanning 9(degrees) latitude. We found higher levels of herbivory at the low-latitude site, but leaf traits showed mixed patterns across sites. Toughness and condensed tannins were higher at the high-latitude site, whereas hydrolysable tannins and hydroxycinnamic acids were higher at the low-latitude site. At the microhabitat scale, experimental warming increased herbivory, but did not affect any of the measured leaf traits. Condensed tannins were negatively correlated with herbivory, suggesting that they drive variation in leaf damage at both scales. Moreover, the effects of microhabitat warming on herbivory and leaf traits were consistent across sites, i.e. effects at the microhabitat scale play out similarly despite variation in factors acting at broader scales. These findings together suggest that herbivory responds to both microhabitat (warming) and broad-scale environmental factors, whereas leaf traits appear to respond more to environmental factors operating at broad scales (e.g. macroclimatic factors) than to warming at the microhabitat scale. In turn, leaf secondary chemistry (tannins) appears to drive both broad-scale and microhabitat-scale variation in herbivory. Further studies are needed using reciprocal transplants with more populations across a greater number of sites to tease apart plant plasticity from genetic differences contributing to leaf trait and associated herbivory responses across scales and, in doing so, better understand the potential for dynamics such as local adaptation and range expansion or contraction under shifting climatic regimes

    Analisis Keanekaragaman Jenis dan Pola Penyebaran Pohon di Mata Air Wahang Kinok Desa Boru Kecamatan Wulanggitang Kabupaten Flores Timur.

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    Penelitian ini bertujuan untuk menganalisis keanekaragaman jenis dan pola penyebaran pohon  di kawasan mata air Wahang Kinok desa Boru kecamatan Wulanggitang kabupaten Flores Timur. Jenis penelitian ini adalah  penelitian kuantitatif berupa studi komposisi dengan metode survey dan iventarisasi jenis pohon pada setiap sampel pengamatan yang ditentukan di sepanjang garis transek. Hasil penelitian menunjukan keanekaragaman jenis pohon tergolong rendah dengan indeks keanekaragaman -2,047 dan pola penyebaran pohon tergolong merata dengan nilai (Id1). Dan upaya dalam menjaga kawasan mata air wahang kinok di Desa Boru Kecamatan Wulanggitang adalah reboisasi dan di adakan sermoni Pa,u botik waimatan. Hasil penelitian ini di harapkan adanya kemungkianan untuk menanam kembali jenis pohon di kawasan mata air Wahang Kinok di desa Boru kecamatan Wulanngitang

    PENGARUH KOMITMEN PROFESIONAL, SOSIALISASI ANTISIPATIF DAN LOCUS OF CONTROL TERHADAP WHISTLEBLOWING INTENTION: (Studi Kasus Pada SKPD Pemerintah Daerah Kabupaten Flores Timur)

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    The purpose of this study was to determine (1) the effect of professional commitment on whistleblowing intention. (2) the effect of anticipatory socialization on whistleblowing intention. (3) the effect of locus of control on whistleblowing intention. This type of research is quantitative research. The data analysis used is descriptive quantitative to measure the influence of professional commitment, anticipatory socialization and locus of control on whistleblowing intention with the help of the Statistical Package for the Social Sciens (SPSS) program for windows. The results of this study indicate (1) Professional Commitment has a significant effect on Whistleblowing Intention in the Regional Government SKPD of East Flores Regency. This result is evidenced by the coefficient value of the Professional Commitment variable of 0.297 with tcount> ttable (2.354> 1.672) and a significant level of 0.022 <0.05. (2) Anticipatory Socialization has a significant effect on Whistleblowing Intention in the Regional Government SKPD of East Flores Regency. This result is evidenced by the coefficient value of the Anticipatory Socialization variable of 0.289 with tcount> ttable (2.195> 1.672) and a significant level of 0.033 <0.05. (3) Locus of Control has a significant effect on Whistleblowing Intention in the Regional Government SKPD of East Flores Regency. These results are evidenced by the value of the coefficient of the Locus of Control variable of 0.236 with tcount> ttable (2.105> 1.672) and a significant level of 0.040 <0.05

    Biotic and abiotic drivers of intraspecific trait variation within plant populations of three herbaceous plant species along a latitudinal gradient

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    Background: The importance of intraspecific trait variation (ITV) is increasingly acknowledged among plant ecologists. However, our understanding of what drives ITV between individual plants (ITVBI) at the population level is still limited. Contrasting theoretical hypotheses state that ITVBI can be either suppressed (stress-reduced plasticity hypothesis) or enhanced (stress-induced variability hypothesis) under high abiotic stress. Similarly, other hypotheses predict either suppressed (niche packing hypothesis) or enhanced ITVBI (individual variation hypothesis) under high niche packing in species rich communities. In this study we assess the relative effects of both abiotic and biotic niche effects on ITVBI of four functional traits (leaf area, specific leaf area, plant height and seed mass), for three herbaceous plant species across a 2300 km long gradient in Europe. The study species were the slow colonizing Anemone nemorosa, a species with intermediate colonization rates, Milium effusum, and the fast colonizing, non-native Impatiens glandulifera. Results: Climatic stress consistently increased ITVBI across species and traits. Soil nutrient stress, on the other hand, reduced ITVBI for A. nemorosa and I. glandulifera, but had a reversed effect for M. effusum. We furthermore observed a reversed effect of high niche packing on ITVBI for the fast colonizing non-native I. glandulifera (increased ITVBI), as compared to the slow colonizing native A. nemorosa and M. effusum (reduced ITVBI). Additionally, ITVBI in the fast colonizing species tended to be highest for the vegetative traits plant height and leaf area, but lowest for the measured generative trait seed mass. Conclusions: This study shows that stress can both reduce and increase ITVBI, seemingly supporting both the stress-reduced plasticity and stress-induced variability hypotheses. Similarly, niche packing effects on ITVBI supported both the niche packing hypothesis and the individual variation hypothesis. These results clearly illustrates the importance of simultaneously evaluating both abiotic and biotic factors on ITVBI. This study adds to the growing realization that within-population trait variation should not be ignored and can provide valuable ecological insights

    Super-regional land-use change and effects on the grassland specialist flora

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    Habitat loss through land-use change is the most pressing threat to biodiversity worldwide. European semi-natural grasslands have suffered an ongoing decline since the early twentieth century, but we have limited knowledge of how grassland loss has affected biodiversity across large spatial scales. We quantify land-use change over 50-70 years across a 175,000 km(2) super-region in southern Sweden, identifying a widespread loss of open cover and a homogenisation of landscape structure, although these patterns vary considerably depending on the historical composition of the landscape. Analysing species inventories from 46,796 semi-natural grasslands, our results indicate that habitat loss and degradation have resulted in a decline in grassland specialist plant species. Local factors are the best predictors of specialist richness, but the historical landscape predicts present-day richness better than the contemporary landscape. This supports the widespread existence of time-lagged biodiversity responses, indicating that further species losses could occur in the future

    Building Cohesion in Distributed Telemedicine Teams Findings from the Department of Veterans Affairs National Telestroke Program

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    Background: As telemedicine adoption increases, so does the importance of building cohesion among physicians in telemedicine teams. For example, in acute telestroke services, stroke specialists provide rapid virtual stroke assessment and treatment to patients at hospitals without stroke specialty care. In the National Telestroke Program (NTSP) of the U.S. Department of Veterans Affairs, a virtual (distributed) hub of stroke specialists throughout the country provides 24/7 consultations nationwide. We examined how these specialists adapted to distributed teamwork, and we identied cohesion-related factors inprogram development and support. Methods: We conducted a case study of the stroke specialists employed by the NTSP. Semi-structured, condential interviews with stroke specialists in the virtual hub were recorded and transcribed. We explored the extent to which these specialists had developed a sense of shared identity and teamcohesion, and we identied factors in this development. Using a qualitative approach with constant comparison methods, two researchers coded each interview transcript independently using a shared codebook. We used matrix displays to identify themes, with special attention to team cohesion, communication, trust, and satisfaction. Results: Of 13 specialists with at least 8 months of NTSP practice, 12 completed interviews; 7 had previously practiced in telestroke programs in other healthcare systems. Interviewees reported high levels of trust and team cohesion, sometimes even more with their virtual colleagues than with local colleagues. Factors facilitating perceived team cohesion included a weekly case conference call, a sense of transparency in discussing challenges, engagement in NTSP development tasks, and support from the NTSP leadership. Although lack of in-person contact was associated with lower cohesion, annual in-person NTSP meetings helped mitigate this issue. Despite technical challenges in establishing a new telehealth system within existing national infrastructure, providers reported high levels of satisfaction with the NTSP.Conclusion: A virtual telestroke hub can provide a sense of team cohesion among stroke specialists at a level comparable with a standard co-located practice. Engaging in transparent discussion of challenging cases, reviewing new clinical evidence, and contributing to program improvements may promotecohesion in distributed telemedicine teamsThis work was funded by the Veterans Health Administration (VHA) Office of Rural Health (016ORH), VHA Office of Specialty Care, VA Health Services Research and Development (HSR&D) Precision Monitoring Quality Enhancement Research Initiative (QUE 15-280). Funding sources had no role in study design, data collection, data analysis, data interpretation, or manuscript writing. The views expressed herein are those of the authors and do not necessarily reflect the views of the U.S. Department of Veterans Affairs

    Impact of an invasive alien plant on litter decomposition along a latitudinal gradient

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    Invasive alien plant effects on ecosystem functions are often difficult to predict across environmental gradients due to the context-dependent interactions between the invader and the recipient communities. Adopting a functional trait-based framework could provide more mechanistic predictions for invasive species' impacts. In this study, we contrast litter decomposition rates among communities with and without the invasive plant Impatiens glandulifera in five regions along a 1600 km long latitudinal gradient in Europe. Across this gradient, four functional traits, namely leaf dry matter content (LDMC), specific leaf area (SLA), stem-specific density (SSD), and plant height, are correlated to rates of litter decomposition of standardized rooibos (labile), green tea (recalcitrant), and I. glandulifera litter. Our results show that both invaded and non-invaded plant communities had a higher expression of acquisitive traits (low LDMC and SSD, high SLA) with increasing temperature along the latitudinal gradient, partly explaining the variation in decomposition rates along the gradient. At the same time, invasion shifted community trait composition toward more acquisitive traits across the latitudinal gradient. These trait changes partly explained the increased litter decomposition rates of the labile litter fraction of rooibos and I. glandulifera litter in invaded communities, a shift that was most evident in the warmer study regions. Plant available nitrogen was lower in invaded communities, likely due to high nutrient uptake by I. glandulifera. Meanwhile, the coldest study region was characterized by a reversed effect of invasion on decomposition rates. Here, community traits related to low litter quality and potential allelopathic effects of the invader resulted in reduced litter decomposition rates, suggesting a threshold temperature at which invader effects on litter decomposition turn positive. This study therefore illustrates how functional trait changes toward acquisitive traits can help explain invader-induced changes in ecosystem functions such as increased litter decomposition

    Initial oak regeneration responses to experimental warming along microclimatic and macroclimatic gradients

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    Quercus spp. are one of the most important tree genera in temperate deciduous forests in terms of biodiversity, economic and cultural perspectives. However, natural regeneration of oaks, depending on specific environmental conditions, is still not sufficiently understood. Oak regeneration dynamics are impacted by climate change, but these climate impacts will depend on local forest management and light and temperature conditions. Here, we studied germination, survival and seedling performance (i.e. aboveground biomass, height, root collar diameter and specific leaf area) of four oak species (Q. cerris, Q. ilex, Q. robur and Q. petraea). Acorns were sown across a wide latitudinal gradient, from Italy to Sweden, and across several microclimatic gradients located within and beyond the species' natural ranges. Microclimatic gradients were applied in terms of forest structure, distance to the forest edge and experimental warming. We found strong interactions between species and latitude, as well as between microclimate and latitude or species. The species thus reacted differently to local and regional changes in light and temperature ; in southern regions the temperate Q. robur and Q. petraea performed best in plots with a complex structure, whereas the Mediterranean Q. ilex and Q. cerris performed better in simply structured forests with a reduced microclimatic buffering capacity. The experimental warming treatment only enhanced height and aboveground biomass of Mediterranean species. Our results show that local microclimatic gradients play a key role in the initial stages of oak regeneration; however, one needs to consider the species-specific responses to forest structure and the macroclimatic context
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