PREDISPERSAL SEED PREDATION OF CANADA THISTLE

1985 ◽  
Vol 117 (9) ◽  
pp. 1075-1081 ◽  
Author(s):  
S.F. Forsyth ◽  
A.K. Watson
Keyword(s):  
Seed Predation ◽  
Population Regulation ◽  
Geographical Location ◽  
Cirsium Arvense ◽  
Canada Thistle ◽  
Seed Predator ◽  
Microscopic Studies ◽  
Predispersal Seed Predation ◽  
The Impact

AbstractPredispersal seed predation of Cirsium arvense (L.) Scop. (Asteraceae) by Orellia ruficauda (Fabr.) (Diptera: Tephritidae) occurs in about 20–85% of the seed heads and the proportion of damaged seeds per attacked head averages 20–80% depending on geographical location and sampling date. Microscopic studies of damaged seeds were performed. Although the impact of this seed predator is not severe, it may be an important factor in the population regulation of the weed.

Predispersal seed predation and population dynamics in the perennial understorey herb Actaea spicata

2003 ◽  
Vol 81 (11) ◽  
pp. 1058-1069 ◽  
Author(s):  
Heléne Fröborg ◽  
Ove Eriksson
Keyword(s):  
Population Dynamics ◽  
Seed Predation ◽  
Seedling Recruitment ◽  
Deciduous Forest ◽  
Transition Probabilities ◽  
Coniferous Forest ◽  
Perennial Herb ◽  
Seed Predator ◽  
Predispersal Seed Predation ◽  
The Impact

Predispersal seed predation by a moth larva, Eupithecia immundata Leinig & Zeller (Geometridae), and its impact on population dynamics of the perennial herb Actaea spicata L. were studied during 7 years in deciduous and mixed coniferous forest populations in southeastern Sweden. Twelve population matrix models were constructed based on transition probabilities among six stage classes in the populations. The fraction of seeds consumed varied between 21% and 80% but was not significantly correlated with seed production. Experimental seed addition compensating for seed losses caused by the seed predator resulted in increased seedling emergence in one of the populations. Population growth rate was positive (λ > 1) in 1 of 6 years in the deciduous forest population and in 2 of 6 years in the mixed coniferous forest population. Survival among reproductive individuals contributed most strongly to λ in both populations. In some years, the projected λ changed from positive to negative values because of seed loss caused by E. immundata. However, results suggest that seed predation did not affect λ to any large extent, despite a considerable seed predation. This study is one of the rare efforts to estimate the impact of seed predation on population dynamics of perennial plants.Key words: Actaea spicata, demography, population dynamics, predispersal seed predation, seedling recruitment.

BIOCONTROL OF THE WEED CANADA THISTLE (CIRSIUM ARVENSE): RELEASES AND DEVELOPMENT OF THE GALL FLY UROPHORA CARDUI (DIPTERA: TEPHRITIDAE) IN CANADA

1982 ◽  
Vol 114 (4) ◽  
pp. 349-357 ◽  
Author(s):  
D. P. Peschken ◽  
D. B. Finnamore ◽  
A. K. Watson
Keyword(s):  
New Brunswick ◽  
Cirsium Arvense ◽  
Winter Mortality ◽  
Western Canada ◽  
Canada Thistle ◽  
Main Shoot ◽  
The West ◽  
The Impact

AbstractThe gall fly Urophora cardui (L.) (Diptera: Tephritidae), native to Europe, was released at 24 locations across Canada beginning in 1974. It became established in Ontario, Quebec, and New Brunswick but died out in all but one location in western Canada. Evidence for winter mortality in the west does not explain the failure of these colonies. Although galls, in particular those on the main shoot, reduce the height of Canada thistle, so far the impact on the host weed, Canada thistle (Cirsium arvense) (L.) Scop., is slight.

Partial predispersal seed predation in Lotus corniculatus L. (Fabaceae)

1996 ◽  
Vol 6 (2) ◽  
pp. 65-69 ◽  
Author(s):  
Jeff Ollerton ◽  
Andrew Lack
Keyword(s):  
Population Dynamics ◽  
Seed Predation ◽  
Plant Traits ◽  
Lotus Corniculatus ◽  
Individual Plant ◽  
Ecological Significance ◽  
Plant Population Dynamics ◽  
Seedling Vigour ◽  
Seed Predator ◽  
Predispersal Seed Predation

AbstractPredispersal seed predation may have implications for plant population dynamics and the evolution of plant traits, but assessing the level of seed predation for an individual plant is not always straightforward. Seeds of Lotus corniculatus (Fabaceae) are often only partially eaten by a weevil seed predator, Apion loti. Samples of these seeds were tested for viability and subsequent seedling vigour. A large proportion of these damaged seeds were viable, and the resulting seedlings almost as vigorous as those from undamaged seeds. The ubiquity of these findings, and their ecological significance, is discussed.

Assessment of the influence of the spatial environment on the socio-economic development of the municipality

2019 ◽  
Vol 40 (3) ◽  
pp. 148-155
Author(s):  
K. N. Yusupov ◽  
V. M. Timiryanova, ◽  
Iu. S. Toktamysheva ◽  
A. F. Zimin,
Keyword(s):  
Economic Development ◽  
Socioeconomic Development ◽  
Statistical Data ◽  
Geographical Location ◽  
Integrated Approach ◽  
The State ◽  
Municipal District ◽  
Socio Economic Development ◽  
Spatial Environment ◽  
The Impact

The article presents a methodology for assessing the impact of spatial environment on the socioeconomic development of municipalities. It relies on existing tools for assessing the state and potential of the geographical location of municipalities. An integrated approach allows to determine the potential of the interaction of the municipality with the neighbors of the first and second order. The methodology was tested on statistical data on the Blagovarsky municipal district.

Individual crop size increases predispersal predation by beetles in a tropical palm

2020 ◽  
pp. 1-4
Author(s):  
Morgana Maria Arcanjo Bruno ◽  
Klécia Gili Massi ◽  
Alexander V. Christianini ◽  
John du Vall Hay
Keyword(s):  
Seed Predation ◽  
Positive Influence ◽  
Reproductive Phenology ◽  
Individual Plant ◽  
Crop Size ◽  
Seed Predators ◽  
Plant Trait ◽  
Predispersal Seed Predation ◽  
Total Seed ◽  
Number Of Seeds

Abstract Predispersal seed predation is one of the main causes of seed mortality in plant populations, contributing to decreased plant recruitment. Seed loss has previously been found to be related to crop size. Thus, we examined the influence of individual crop size on predispersal seed predation by beetles in the palm Syagrus flexuosa in the Brazilian savanna. The study was carried out in three tropical woodland savanna sites, where we sampled the total seed crop of 46 fruiting palms and checked the presence of beetle larvae inside all seeds per plant. We observed predispersal seed predation of S. flexuosa from all sites and a high variation in the number of seeds preyed on per individual palm. Crop size had a positive influence on the number of seeds lost to predispersal seed predators. Variations in levels of predispersal seed predation may also be accounted for by the reproductive phenology of S. flexuosa. If fruits are not available at the same time, less resource is available for predators and therefore a high proportion of seeds may be preyed on. Thus, our study demonstrates that an individual plant trait, crop size, is an important predictor of beetle seed damage per palm and a driver of the number of seeds lost to predispersal seed predators.

scholarly journals The Psychosocial and Somatic Effects of Relocation from Remote Canadian First Nation Communities to Urban Centres on Indigenous Peoples with Chronic Kidney Disease (CKD)

2021 ◽  
Vol 18 (7) ◽  
pp. 3838
Author(s):  
Denise Genereux ◽  
Lida Fan ◽  
Keith Brownlee
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Indigenous Peoples ◽  
Health Care Professionals ◽  
Medical Condition ◽  
Geographical Location ◽  
Well Being ◽  
First Nation ◽  
Urban Centre ◽  
The Impact

Chronic kidney disease, also referred to as end-stage renal disease (ESRD), is a prevalent and chronic condition for which treatment is necessary as a means of survival once affected individuals reach the fifth and final stage of the disease. Dialysis is a form of maintenance treatment that aids with kidney functioning once a normal kidney is damaged. There are two main types of dialysis: hemodialysis (HD) and peritoneal dialysis (PD). Each form of treatment is discussed between the patient and nephrologist and is largely dependent upon the following factors: medical condition, ability to administer treatment, supports, geographical location, access to necessary equipment/supplies, personal wishes, etc. For Indigenous Peoples who reside on remote Canadian First Nation communities, relocation is often recommended due to geographical location and limited access to both health care professionals and necessary equipment/supplies (i.e., quality of water, access to electricity/plumbing, etc). Consequently, the objective of this paper is to determine the psychosocial and somatic effects for Indigenous Peoples with ESRD if they have to relocate from remote First Nation communities to an urban centre. A review of the literature suggests that relocation to urban centres has negative implications that are worth noting: cultural isolation, alienation from family and friends, somatic issues, psychosocial issues, loss of independence and role adjustment. As a result of relocation, it is evident that the impact is profound in terms of an individuals’ mental, emotional, physical and spiritual well-being. Ensuring that adequate social support and education are available to patients and families would aid in alleviating stressors associated with managing chronic kidney disease.

scholarly journals Do Long-Term Natural Disasters Influence Social Trust? Empirical Evidence from China

2021 ◽  
Vol 18 (14) ◽  
pp. 7280
Author(s):  
Yao Li ◽  
Haoyang Li ◽  
Jianqing Ruan
Keyword(s):  
Natural Disasters ◽  
Natural Disaster ◽  
Social Trust ◽  
Geographical Location ◽  
Household Survey ◽  
Flood Frequency ◽  
Psychological Characteristics ◽  
The North ◽  
The Impact

The natural environment is one of the most critical factors that profoundly influences human races. Natural disasters may have enormous effects on individual psychological characteristics. Using China’s long-term historical natural disaster dataset from 1470 to 2000 and data from a household survey in 2012, we explore whether long-term natural disasters affect social trust. We find that there is a statistically significant positive relationship between long-term natural disaster frequency and social trust. We further examine the impact of long-term natural disaster frequency on social trust in specific groups of people. Social trust in neighbors and doctors is stronger where long-term natural disasters are more frequent. Our results are robust after we considering the geographical difference. The effect of long-term natural disasters remains positively significant after we divide the samples based on geographical location. Interestingly, the impact of long-term flood frequency is only significant in the South and the impact of long-term drought frequency is only significant in the North.

scholarly journals Experiences of nurses caring for respiratory patients during the first wave of the COVID-19 pandemic: an online survey study

2021 ◽  
Vol 8 (1) ◽  
pp. e000987
Author(s):  
Nicola J Roberts ◽  
Carol A Kelly ◽  
Kate A Lippiett ◽  
Emma Ray ◽  
Lindsay Welch
Keyword(s):  
Mental Health ◽  
Online Survey ◽  
Demographic Data ◽  
Geographical Location ◽  
Working Environment ◽  
Survey Study ◽  
British Thoracic Society ◽  
Healthcare Team ◽  
Free Text ◽  
The Impact

BackgroundNurses have been at the forefront of the pandemic response, involved in extensive coordination of services, screening, vaccination and front-line work in respiratory, emergency and intensive care environments. The nature of this work is often intense and stress-provoking with an inevitable psychological impact on nurses and all healthcare workers. This study focused on nurses working in respiratory areas with the aim of identifying and characterising the self-reported issues that exacerbated or alleviated their concerns during the first wave of the COVID-19 pandemic.MethodsAn online survey was developed consisting of 90 questions using a mixture of open-ended and closed questions. Participant demographic data were also collected (age, gender, ethnicity, number of years qualified, details of long-term health conditions, geographical location, nursing background/role and home life). The online survey was disseminated via social media and professional respiratory societies (British Thoracic Society, Primary Care Respiratory Society, Association of Respiratory Nurse Specialists) over a 3-week period in May 2020 and the survey closed on 1 June 2020.ResultsThe study highlights the experiences of nurses caring for respiratory patients during the first wave of the pandemic in early 2020. Concerns were expressed over the working environment, the supply and availability of adequate protective personal equipment, the quality of care individuals were able to deliver, and the impact on mental health to nurses and their families. A high number provided free-text comments around their worries and concerns about the impact on their household; these included bringing the virus home, the effect on family members worrying about them, mental health and the impact of changing working patterns, and managing with children. Although both formal and informal support were available, there were inconsistencies in provision, highlighting the importance of nursing leadership and management in ensuring equity of access to services.ConclusionsSupport for staff is essential both throughout the pandemic and afterwards, and it is important that preparation of individuals regarding building resilience is recognised. It is also clear that psychological support and services for nurses and the wider healthcare team need to be available and quickly convened in the event of similar major incidents, either global or local.

Sign in / Sign up

Export Citation Format

Share Document