Combined effects of inflorescence architecture, display size, plant density and empty flowers on bumble bee behaviour: experimental study with artificial inflorescences

Oecologia ◽  
2008 ◽  
Vol 156 (2) ◽  
pp. 341-350 ◽  
Author(s):  
Hiroshi S. Ishii ◽  
Yuimi Hirabayashi ◽  
Gaku Kudo
Keyword(s):  
Experimental Study ◽  
Display Size ◽  
Plant Density ◽  
Bumble Bee ◽  
Combined Effects ◽  
Inflorescence Architecture

scholarly journals LABORATORY SIMULATIONS OF WAVE ATTENUATION BY AN EMERGENT VEGETATION OF ARTIFICIAL PHRAGMITES AUSTRALIS: AN EXPERIMENTAL STUDY OF AN OPEN-CHANNEL WAVE FLUME

2015 ◽  
Vol 23 (4) ◽  
pp. 251-266 ◽  
Author(s):  
Li YIPING ◽  
Desmond Ofosu ANIM ◽  
Ying WANG ◽  
Chunyang TANG ◽  
Wei DU ◽  
...  
Keyword(s):  
Experimental Study ◽  
Phragmites Australis ◽  
Wave Height ◽  
Plant Density ◽  
Wave Attenuation ◽  
Emergent Vegetation ◽  
Irregular Waves ◽  
Shore Protection ◽  
Near Shore ◽  
Wave Conditions

This paper presents a well-controlled laboratory experimental study to evaluate wave attenuation by artificial emergent plants (Phragmites australis) under different wave conditions and plant stem densities. Results showed substantial wave damping under investigated regular and irregular wave conditions and also the different rates of wave height and within canopy wave-induced flows as they travelled through the vegetated field under all tested conditions. The wave height decreased by 6%–25% at the insertion of the vegetation field and towards the downstream at a mean of 0.2 cm and 0.32 cm for regular and irregular waves respectively. The significant wave height along the vegetation field ranged from 0.89–1.76 cm and 0.8–1.28 cm with time mean height of 1.38 cm and 1.11 cm respectively for regular and irregular waves. This patterns as affected by plant density and also location from the leading edge of vegetation is investigated in the study. The wave energy attenuated by plant induced friction was predicted in terms of energy dissipation factor (fe) by Nielsen’s (1992) empirical model. Shear stress as a driving force of particle resuspension and the implication of the wave attenuation on near shore protection from erosion and sedimentation was discussed. The results and findings in this study will advance our understanding of wave attenuation by an emergent vegetation of Phragmites australis, in water system engineering like near shore and bank protection and restoration projects and also be employed for management purposes to reduce resuspension and erosion in shallow lakes.

scholarly journals Experimental Study of Combined Effects of Gamma and Laser Radiations on the Properties of Silicate Glass Materials

2015 ◽  
Vol 3 (3) ◽  
pp. 39-45
Author(s):  
R. T. Khaydarov ◽  
H. B. Beisinbaeva ◽  
R. R. Khaydarov ◽  
F. R. Tojinazarov ◽  
G. R. Berdiyorov ◽  
...  
Keyword(s):  
Experimental Study ◽  
Silicate Glass ◽  
Combined Effects

Combined Effects of Severity of Cleft Impairment and Facial Attractiveness on Social Perception: An Experimental Study

1993 ◽  
Vol 30 (1) ◽  
pp. 82-86 ◽  
Author(s):  
Joyce M. Tobiasen ◽  
John M. Hiebert
Keyword(s):  
Experimental Study ◽  
Children And Adolescents ◽  
Social Perception ◽  
Negative Impact ◽  
Facial Attractiveness ◽  
Social Perceptions ◽  
Combined Effects

Children and adolescents provided their impressions of stimulus faces that systematically varied in attractiveness and severity of cleft impairment. The results indicated that facial attractiveness is a consistent characteristic of cleft-impaired faces. However, facial attractiveness did not moderate the negative impact of cleft impairment on social perception. Reduced severity of impairment did moderate the negativity of social perception. The implications of these findings for our understanding of the effects of cleft impairment on social perceptions are discussed.

Experimental Study on Cement Mortar with Bentonite

2013 ◽  
Vol 671-674 ◽  
pp. 1741-1744 ◽  
Author(s):  
Hsien Hua Lee ◽  
C. W. Wang
Keyword(s):  
Experimental Study ◽  
Reinforced Concrete ◽  
Marine Environment ◽  
Cement Mortar ◽  
Combined Effects ◽  
Concrete Material ◽  
Corrosion Resistant ◽  
Steel Bars ◽  
Reinforced Steel ◽  
Physical And Chemical

For an infrastructure construction located in marine environments, maintaining good durability for the structures always imposes serious challenges, especially for the structure made of reinforced concrete. Concrete exposed to marine environment may deteriorate as a result of combined effects of both physical and chemical actions from marine environment. Corrosion of the reinforced steel bars that are embedded in the concrete is the most serious problem. Therefore, a method to protect the reinforced concrete in the marine environment from damages due to material deterioration and corrosion is proposed in this study. The method is through the application of bentonite material by utilizing its very finely divided form so that the larger capillary pores in concrete can be filled up. In this way, the impermeability of concrete material can be enhanced and then improve the corrosion resistant ability of the material.

scholarly journals An Experimental Study on the Combined Effects of n-Hexane and MEK

Sangyo Igaku ◽  
1982 ◽  
Vol 24 (7) ◽  
pp. 763-764
Author(s):  
Y. TAKEUCHI
Keyword(s):  
Experimental Study ◽  
Combined Effects

scholarly journals Visco-plastic models of isothermal lava domes

2000 ◽  
Vol 403 ◽  
pp. 37-65 ◽  
Author(s):  
N. J. BALMFORTH ◽  
A. S. BURBIDGE ◽  
R. V. CRASTER ◽  
J. SALZIG ◽  
A. SHEN
Keyword(s):  
Experimental Study ◽  
Evolution Equation ◽  
Thin Layer ◽  
Yield Stress ◽  
Shear Thinning ◽  
Constitutive Law ◽  
Combined Effects ◽  
Viscoplastic Material ◽  
Lava Domes ◽  
Basal Sliding

The dynamics of expanding domes of isothermal lava are studied by treating the lava as a viscoplastic material with the Herschel–Bulkley constitutive law. Thin-layer theory is developed for radially symmetric extrusions onto horizontal plates. This provides an evolution equation for the thickness of the fluid that can be used to model expanding isothermal lava domes. Numerical and analytical solutions are derived that explore the effects of yield stress, shear thinning and basal sliding on the dome evolution. The results are briefly compared with an experimental study. It is found that it is difficult to unravel the combined effects of shear thinning and yield stress; this may prove important to studies that attempt to infer yield stress from morphology of flowing lava.

An experimental study of floral display size and reproductive success in Viburnum opulus: importance of grouping

1991 ◽  
Vol 69 (2) ◽  
pp. 394-399 ◽  
Author(s):  
Pam G. Krannitz ◽  
M. Anwar Maun
Keyword(s):  
Experimental Study ◽  
Reproductive Success ◽  
Key Words ◽  
Small Groups ◽  
Display Size ◽  
Significant Proportion ◽  
Floral Display ◽  
Flower Number ◽  
Viburnum Opulus ◽  
Floral Display Size

Two components of the floral display of Viburnum opulus L. were manipulated to determine their effect on fruit initiation and maturation. We altered the size of the floral display by planting individual shrubs in groups of 1, 5, or 10 in 1985 and in groups of 2 or 6 in 1986. In addition, we changed inflorescence size by altering the number of sterile accessory flowers per inflorescence: 0, 4, or untreated in 1985 and 0 or untreated in 1986. The sterile-flower treatment did not explain a significant proportion of the variation in fruit initiation or maturation. In contrast, the plant-grouping treatment was significant in 1985 but not in 1986. The number and proportion of fruits initiated were higher in larger groups of plants than in small groups in 1985 (P < 0.0001 for analyses performed at group and plant levels). The proportion of fruits initiated in group sizes 1, 5, and 10 was 6.9, 15.0, and 22.7% per plant, respectively, and 4.3, 9.1, and 19.4% per inflorescence, respectively. The larger groups did not initiate or mature proportionally more fruits in 1986. Twice as much rain fell in 1986 as in 1985, and shrubs produced more fruits overall (32.2% fruit initiation versus 11% in 1985), but it is not clear why group size differences did not have an effect on fruit initiation and maturation in 1986. Within the plant-grouping treatment fruit initiation and maturation were always significantly correlated with flower number (P < 0.0001) in both 1985 and 1986, but the increase in the number of fruits initiated was not proportional to the increase in flower number. Key words: floral display size, fruit initiation, plant grouping, pollination, Viburum opulus.

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