scholarly journals Long-Term Seeding Outcomes in Slash Piles and Skid Trails after Conifer Removal

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 839
Author(s):  
Becky K. Kerns ◽  
Michelle A. Day ◽  
Dana Ikeda
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Fire Hazard ◽  
Fire Behavior ◽  
Treatment Strategies ◽  
Seed Source ◽  
Seed Sources ◽  
Before And After ◽  
Exotic Grass

Conifer removal in interior woodland ecosystems of the western US is a common management treatment used to decrease fire hazard and shift woodlands to more historical states. Woody material is frequently removed by skidding material off site and via slash pile burning. Assessing the long-term outcomes of seeding treatments after such ground disturbing activities is critical for informing future management and treatment strategies. Using two designed experiments from a central Oregon juniper woodland, we resampled slash piles and skid trails 8 years after seeding. Our objectives were to assess the long-term vegetation response to conifer removal, ground disturbance, and seeding source (cultivar and local) in slash piles and skid trails. We found that seeded species persisted in the long term, but abundance patterns depended on the species, seed source, and the type of disturbance. In general, there were more robust patterns of persistence after pile burning compared to skid trails. Seeding also suppressed exotic grass cover in the long term, particularly for the local seed source. However, the invasion levels we report are still problematic and may have impacts on biodiversity, forage and fire behavior. Our short-term results were not predictive of longer-term outcomes, but short- and long-term patterns were somewhat predictable based on species life history traits and ecological succession. The use of a mix of species with different life history traits may contribute to seeding success in terms of exotic grass suppression. Lastly, our results suggest that locally adapted seed sources may perform as well or better compared to cultivars. However, more aggressive weed treatments before and after conifer removal activities and wider seeding application may be needed to effectively treat exotic grass populations.

Calcium effects on life-history traits in a wild population of the great tit (Parus major): analysis of long-term data at several spatial scales

Oecologia ◽  
2008 ◽  
Vol 159 (2) ◽  
pp. 463-472 ◽  
Author(s):  
Teddy Albert Wilkin ◽  
Andrew G. Gosler ◽  
Dany Garant ◽  
S. James Reynolds ◽  
Ben C. Sheldon
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Wild Population ◽  
Spatial Scales ◽  
Parus Major ◽  
Great Tit ◽  
Calcium Effects ◽  
Term Data

scholarly journals Does immunological remission, defined as disappearance of autoantibodies, occur with current treatment strategies? A long-term follow-up study in rheumatoid arthritis patients who achieved sustained DMARD-free status

2019 ◽  
Vol 78 (11) ◽  
pp. 1497-1504 ◽  
Author(s):  
Debbie M Boeters ◽  
Leonie E Burgers ◽  
René EM Toes ◽  
Annette van der Helm-van Mil
Keyword(s):  
Rheumatoid Arthritis ◽  
Treatment Strategies ◽  
Signs And Symptoms ◽  
Current Treatment ◽  
Dmard Therapy ◽  
Before And After ◽  
Long Term Follow Up ◽  
Free Status

ObjectivesSustained disease-modifying antirheumatic drug (DMARD)-free status, the sustained absence of synovitis after cessation of DMARD therapy, is infrequent in autoantibody-positive rheumatoid arthritis (RA), but approximates cure (ie, disappearance of signs and symptoms). It was recently suggested that immunological remission, defined as disappearance of anti-citrullinated protein antibodies (ACPA) and rheumatoid factor (RF), underlies this outcome. Therefore, this long-term observational study determined if autoantibodies disappear in RA patients who achieved sustained DMARD-free remission.MethodsWe studied 95 ACPA-positive and/or RF-positive RA patients who achieved DMARD-free remission after median 4.8 years and kept this status for the remaining follow-up (median 4.2 years). Additionally, 21 autoantibody-positive RA patients with a late flare, defined as recurrence of clinical synovitis after a DMARD-free status of ≥1 year, and 45 autoantibody-positive RA patients who were unable to stop DMARD therapy (during median 10 years) were studied. Anti-cyclic citrullinated peptide 2 (anti-CCP2) IgG, IgM and RF IgM levels were measured in 587 samples obtained at diagnosis, before and after achieving DMARD-free remission.Results13% of anti-CCP2 IgG-positive RA patients had seroreverted when achieving remission. In RA patients with a flare and persistent disease this was 8% and 6%, respectively (p=0.63). For anti-CCP2 IgM and RF IgM, similar results were observed. Evaluating the estimated slope of serially measured levels revealed that RF levels decreased more in patients with than without remission (p<0.001); the course of anti-CCP2 levels was not different (p=0.66).ConclusionsSustained DMARD-free status in autoantibody-positive RA was not paralleled by an increased frequency of reversion to autoantibody negativity. This form of immunological remission may therefore not be a treatment target in patients with classified RA.

scholarly journals Can aphids learn to cope with the pressure of endophytic fungi in their food plants?

2007 ◽  
Vol 13 ◽  
pp. 333-336
Author(s):  
S.A. Härri ◽  
J. Krauss ◽  
C.B. Müller
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Rhopalosiphum Padi ◽  
Food Plants ◽  
Long Term Effects ◽  
Test Environment ◽  
Life History Parameters ◽  
Strain Adaptation ◽  
The Difference

Plant-endophyte associations can have major impacts on the dynamics of consumer interaction-webs but long-term effects of mycotoxins and the ability of herbivores to adapt to these toxins have not been studied. To understand the potential of aphids to cope with mycotoxins, we compared the life-history parameters for aphids conditioned for several generations on endophyte-infected plants with those of endophyte-naïve aphids on both endophyteinfected and endophyte-free grasses. Aphids conditioned on endophyte-infected plants produced more offspring during the first days of adulthood than endophyte-naïve aphids independent of the endophyte infection of the test environment. However, the endophyte-conditioned aphids tended to have a shorter lifespan, which resulted in similar numbers of total offspring produced for endophyte-conditioned and endophyte-naïve aphids. The difference in life-history parameters caused by the conditioning environment suggests that the effects of endophytes on herbivore life-history traits may represent an adaptive change that should be considered in future studies of endophyte-herbivore interactions. Keywords: Rhopalosiphum padi, Neotyphodium lolii, Lolium perenne, common strain, adaptation, long-term effects, microbes, endosymbionts, reproductive strategy, life-history traits

scholarly journals How social behaviour and life-history traits change with age and in the year prior to death in female yellow-bellied marmots

2021 ◽  
Vol 376 (1823) ◽  
pp. 20190745
Author(s):  
Svenja B. Kroeger ◽  
Daniel T. Blumstein ◽  
Julien G. A. Martin
Keyword(s):  
Life History ◽  
Social Behaviour ◽  
Life History Traits ◽  
Evolutionary Ecology ◽  
Natural Populations ◽  
Late Life ◽  
Integrative Approach ◽  
Trade Offs ◽  
Social Behaviours

Studies in natural populations are essential to understand the evolutionary ecology of senescence and terminal allocation. While there are an increasing number of studies investigating late-life variation in different life-history traits of wild populations, little is known about these patterns in social behaviour. We used long-term individual based data on yellow-bellied marmots (Marmota flaviventer) to quantify how affiliative social behaviours and different life-history traits vary with age and in the last year of life, and how patterns compare between the two. We found that some social behaviours and all life-history traits varied with age, whereas terminal last year of life effects were only observed in life-history traits. Our results imply that affiliative social behaviours do not act as a mechanism to adjust allocation among traits when close to death, and highlight the importance of adopting an integrative approach, studying late-life variation and senescence across multiple different traits, to allow the identification of potential trade-offs.This article is part of the theme issue ‘Ageing and sociality: why, when and how does sociality change ageing patterns?’

Effects of long-term exposure to two fungicides, pyrimethanil and tebuconazole, on survival and life history traits of Italian tree frog (Hyla intermedia)

2016 ◽  
Vol 172 ◽  
pp. 56-66 ◽  
Author(s):  
Ilaria Bernabò ◽  
Antonello Guardia ◽  
Rachele Macirella ◽  
Settimio Sesti ◽  
Antonio Crescente ◽  
...  
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Tree Frog

scholarly journals Life-history evolution of class-structured populations in fluctuating environments

2021 ◽  
Author(s):  
Sébastien Lion ◽  
Sylvain Gandon
Keyword(s):  
Life History ◽  
Competitive Ability ◽  
Life History Traits ◽  
Life History Evolution ◽  
Structured Populations ◽  
New Approach ◽  
Selection Gradients ◽  
Evolution Of Life ◽  
History Evolution

AbstractWhat is the influence of periodic environmental fluctuations on life-history evolution? We present a general theoretical framework to understand and predict the long-term evolution of life-history traits under a broad range of ecological scenarios. Indeed, this analysis yields time-varying selection gradients that help dissect the influence of the fluctuations of the environment on the competitive ability of a specific life-history mutation. We use this framework to analyse the evolution of key life-history traits of pathogens, such as transmission and virulence. These examples reveal how periodic fluctuations of the environment can affect the evolution of pathogens, and illustrate the usefulness and broad applicability of this new approach.

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