scholarly journals Too Much of a Good Thing – Using Water to Control the Aquatic Invasive Yellow Flag Iris (Iris Pseudacorus L.)

Author(s):  
Catherine Tarasoff ◽  
Sharon Gillies

Abstract Invasions of Iris pseudacorus L. (yellow flag iris) into wetland environments can result in changes to the functioning of the ecosystem. Field-based and greenhouse studies were initiated to study the effect of water depth on regrowth rates of cut stems of yellow flag iris. The field-based experiment occurred at 41 independent populations around the perimeter of a single wetland. The greenhouse experiment was conducted to further study the effect of water depth and duration of submersion on rhizome mortality. In both studies, treatments were compared against controls. In the field-study, yellow flag iris regrowth was significantly affected by water, though there was no relationship between water depth and percent regrowth. In the greenhouse study, there was a significant positive relationship between duration of submersion and percent mortality of rhizomes. And, there was no relationship between water depth and percent mortality; indicating that as little as 5 cm of water is sufficient to kill yellow flag iris rhizomes, if the stems are cut to the base of the plant. Our results indicate a simple technique can control yellow flag iris within aquatic ecosystems without the need for chemicals or laborious hand removal.Nomenclature: yellow flag iris, Iris pseudacorus (L.) IRPS

2021 ◽  
pp. 1-22
Author(s):  
Alex L. Stoneburner ◽  
Paul J. Meiman ◽  
Troy W. Ocheltree ◽  
Scott J. Nissen ◽  
Scott Bradfield

Abstract Yellow-Flag Iris (Iris pseudacorus L.) is a non-native, invasive wetland plant that disrupts riparian ecosystem processes and is widely distributed across the US and Canada. Due to its physiological and morphological characteristics, I. pseudacorus has the capacity to exclude native vegetation and form extensive monocultures in both lotic and lentic wetland systems. Methods commonly used to manage I. pseudacorus include manual (e.g., hand-pulling, digging) and mechanical (e.g., mowing) treatments for small populations and herbicide applications for larger populations; however, herbicide applications near water may be prohibited due to label restrictions. The objective of this research was to evaluate cattle trampling as a non-chemical method to reduce I. pseudacorus in riparian habitats. A greenhouse study was conducted to investigate the effects of inundation and two different timings of simulated trampling on I. pseudacorus density, height, and soluble sugar concentrations in the rhizomes. A complementary field demonstration was established on a ranch in northwestern Nebraska to evaluate cattle trampling effects on I. pseudacorus density and height after two consecutive years. Simulated cattle trampling in the greenhouse had no effect on I. pseudacorus density or height of non-inundated samples. However, combining trampling with inundation reduced I. pseudacorus density from a median of 10 iris per pot to 0 iris per pot and median height from 0.35 m to 0 m by the conclusion of the study. Additionally, the field demonstration resulted in reductions of both density and height of I. pseudacorus after two consecutive years (72% and 67% reduction, respectively). Soluble sugar concentrations were not impacted by any treatment.


2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Dr. Thiyam Kiran Singh ◽  
Aastha Dhingra

Love is more than a close friendship. It acts as a major facilitator of interpersonal relationship. Love is positive in nature and leaves a positive affect on every individual. An individual in love not only feels positive but spreads positivity around. They smile, be kind to other people, behave compassionately with everyone. If the person is happy then he is likely to be psychologically and emotionally healthy. The current study aimed at understanding the relationship between love, affect and wellbeing among young females aged between 20-25 years. The study reported a significant positive relationship between love and positive affect with the significant correlation of 0.29 at 0.05 levels (p<0.05). It was also found a significant positive relationship between love and wellbeing with the significant correlation of 0.58 at 0.01 level (p<0.01). This means that people in love experience positive emotions and healthy wellbeing. The correlation between love and negative affect came out to be insignificant. The correlation turned out to be -0.13. This means that people in love do not experience negative emotions.


2016 ◽  
Vol 44 (3) ◽  
pp. 509-517 ◽  
Author(s):  
Yanhan Zhu

The 2 types of exchange relationship perceptions—social exchange relationship perceptions (SERPs) and economic exchange relationship perceptions (EERPs)—constitute the primary concept for understanding individual behavior in the workplace. Using a sample of 581 employees from Mainland China, I explored the effects of SERPs and EERPs on employee extrarole behavior (ERB), as well as the moderating effect of organization-based self-esteem (OBSE) on the relationships between SERPs and ERB, and between EERPs and ERB. The results revealed a significant positive relationship between SERPs and ERB, a significant negative relationship between EERPs and ERB, and a significant moderating effect for OBSE. Theoretical and practical implications of these findings are discussed.


1987 ◽  
Vol 79 (2) ◽  
pp. 210-216 ◽  
Author(s):  
S. K. De Datta ◽  
W. N. Obcemea ◽  
R. Y. Chen ◽  
J. C. Calabio ◽  
R. C. Evangelista

2016 ◽  
Vol 21 (1) ◽  
pp. 14-20
Author(s):  
Mihaela Man

Abstract In this research on the one hand we analyzed the relationship that exists in terms of motivational persistence and the Big Five dimensions and, on the other hand, organizational citizenship behavior (OCB). The results show that the conscientiousness has been identified as being in a significant positive relationship with OCB. This result is consistent with the data provided by previous researchers. The results also indicate that three conscientiousness facets are in a positive relationship with OCB. These three conscientiousness facets are self-efficacy, cautiousness and orderliness. Agreeableness was not identified as being associated with OCB. At the level of the relationship between motivational persistence factors and OCB, we have identified a significant positive relationship with only one factor: current purpose pursuing. The OCB model has two variables that work best as predictors: high scores with regard to current purpose in terms of the pursuing-motivational persistence factor, and low scores in terms of the imagination-facet of openness to experience.


1983 ◽  
Vol 40 (1) ◽  
pp. 92-95 ◽  
Author(s):  
E. E. Prepas

Total dissolved solids (TDS) and chlorophyll a were not related in 25 lakes which were all off the Precambrian Shield. Both on-shield and off-shield lakes were included in the previous reports which showed a significant relationship between TDS and productivity. When data from on-shield and off-shield lakes were analyzed separately, there was no significant positive relationship between TDS and lake biomass or productivity. It was also shown that mean depth ([Formula: see text]) was as good a predictor of fish production as the TDS: [Formula: see text] ratio, the morphoedaphic index.Key words: TDS, biomass, productivity, morphoedaphic index, chlorophyll a, lakes


2021 ◽  
Vol 71 (10) ◽  
pp. 2442-2444
Author(s):  
Naila Andleeb ◽  
Sadaf Ahsan ◽  
Sadaf Zaheer ◽  
Farhana Sajjad

Present research was intended to examine the association between suicidal ideation and clinical anger among the physically disabled. The Purposive Convenient study was conducted at Artificial Limbs Centre, Fauji Foundation Hospital Rawalpindi from February 2016 to November 2016. The modified scale for suicidal ideation and the clinical anger scale were used for data collection. Sample comprised of 150 physically disabled individuals including 87 (56%) males and 63 (42%) females.  Findings revealed that suicidal ideation had significant positive relationship with clinical anger and females were significantly higher in clinical anger and suicidal ideation as compared to males. Furthermore,results revealed higher mean scores on clinical anger by the participants having the problem of spinal cord 26.10±9.25 and suicidal ideation is higher in persons having problem of polio 15.87±9.41as compared to other physical disabilities. The study highlighted the need develop and enhance mental and physical health. Continuous...


2021 ◽  
Vol 9 (2) ◽  
pp. 69-82
Author(s):  
Sujan Chandra Paul ◽  
Md Harun Or Rosid ◽  
Mohammad Rakibul Islam ◽  
Refat Ferdous

This study investigates the relationship between Foreign Direct Investment (FDI) and some macroeconomic variables such as Gross Domestic Product (GDP), Gross Capital Formation (GCF), Agriculture, Forestry, and Fishing (AFF), Industry, Import, Export, Inflation and Unemployment rate. Panel Data of 14 regional alliances countries from 1990-2018 were collected from The World Bank website. Robust regression models are used in this study. This research found that GDP had significant positive relationship with FDI in all regions except Arab League, EU and G7 countries. GCF had significant positive relationship with FDI in Arab League, BRI, GATT, NAFTA countries & negative relationship in APEC, G7 countries. AFF had significant positive relationship with FDI in BRICS, GATT countries & negative relationship in African Union, ASEAN, BIMSTEC, BRI, BRICS, SAFTA countries. Industry had significant positive relationship with FDI in African Union, BRI, NAFTA, OECD countries and negative relationship in BRICS, G7, G20 countries. Import had significant positive relationship with FDI in African Union, APEC, Arab League, ASIAN, BRI, G7, G20, GATT countries and negative relationship in BRICS countries. Export had significant positive relationship with FDI in BRICS countries and negative relationship in African Union, ASEAN, BRI, G20, GATT, OECD, SAFTA countries. Inflation had significant positive relationship with FDI in GATT, SAFTA countries and negative relationship in African Union, APEC countries. Unemployment rate had significant positive relationship with FDI in African Union, BRI, BRICS, EU, G20, GATT, OECD, SAFTA countries and negative relationship in ASEAN countries.


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