scholarly journals Reproduction and Accompanying Fauna of Red Mason Bee Osmia rufa L. (syn. Osmia bicornis L.) in Areas with Different Levels of Urbanization

2021 ◽  
Vol 65 (1) ◽  
pp. 123-137
Author(s):  
Barbara Zajdel ◽  
Mikołaj Borański ◽  
Kornelia Kucharska ◽  
Dariusz Teper
Keyword(s):  
Habitat Structure ◽  
Population Growth Rate ◽  
Reproductive Parameters ◽  
Solitary Bee ◽  
Ecological Significance ◽  
Habitat Types ◽  
Biological Value ◽  
Urbanized Areas ◽  
Nest Fauna ◽  
Different Levels

Abstract An increasing number of studies show that urbanized areas are habitats of high biological value and ecological significance. Most bee species live in areas altered by man, either in cities - fragmented urban habitats - or in large rural monocultures. Our research is based on three-year observations of population development of the solitary bee Osmia rufa L. in three habitat types: city, suburbs and villages. We compared reproductive parameters and diversity of accompanying nest fauna. Population growth rate was high in all habitats, exceeding five times the number of cocoons placed in the previous year. We found no significant differences in the number of cocoons and brood mortality between areas with different urbanization levels. In nests located in suburbs, parasites and cleptoparasites occupied almost three times more nest chambers than in other habitats. Changes in the habitat structure had a significant impact on the diversity and abundance of accompanying fauna. Our study shows that red mason bees are flexible and easily adapt to new conditions, despite changes caused by urbanization and agriculture.

Propanil Resistance in Populations of Junglerice (Echinochloa colona) in Colombian Rice Fields

Weed Science ◽  
1993 ◽  
Vol 41 (2) ◽  
pp. 201-206 ◽  
Author(s):  
Albert J. Fischer ◽  
Eduardo Granados ◽  
Diego Trujillo
Keyword(s):  
Leaf Area ◽  
Reproductive Parameters ◽  
Considerable Variability ◽  
Relative Growth ◽  
Mean Relative Growth Rate ◽  
Previously Treated ◽  
Ecological Success ◽  
Net Assimilation ◽  
Susceptible Populations ◽  
Different Levels

Dose-response studies estimating GR40 values indicated different levels of propanil resistance in junglerice populations from fields previously treated with propanil, compared to a check population collected where this herbicide had never been used. The GR40 for susceptible populations ranged from 0.36 to 0.50 kg ai ha−1and for resistant populations ranged from 1.10 to 3.10 kg ai ha−1. Considerable variability in growth and morphology existed among populations. Variability in cumulative leaf area, aboveground biomass, mean relative growth rate, mean net assimilation rate, and mean leaf area ratio could not be related to propanil resistance. Competitiveness was not related to propanil resistance either. of several vegetative and reproductive parameters measured at maturity, only grain weight per plant and number of grains per plant were correlated with GR40 (r = −0.73, P = 0.06). This trend towards lower reproductive fitness in propanil-resistant junglerice plants may reduce its ecological success when growing with propanil-susceptible plants in the absence of this herbicide.

scholarly journals Physical and sensory characteristics of pellets elaborated with different levels of corn grits and whey protein concentrate

2016 ◽  
Vol 40 (2) ◽  
pp. 235-243 ◽  
Author(s):  
Anderson Felicori Fernandes ◽  
Raul Antônio Viana Madeira ◽  
Carlos Wanderlei Piler Carvalho ◽  
Joelma Pereira
Keyword(s):  
Whey Protein ◽  
Sensory Analysis ◽  
Whey Protein Concentrate ◽  
Protein Concentrate ◽  
Biological Value ◽  
High Carbohydrate ◽  
Sensory Acceptance ◽  
Absolute Density ◽  
Nutritional Aspect ◽  
Different Levels

ABSTRACT Whey has proteins of high biological value, which has been used as an ingredient in the elaboration of yogurt, milk beverages and as protein concentrates. Food extrusion stands out as one of the most efficient cooking techniques, allowing a number of product types, from soluble flour to convenience products, such as snacks, which have high acceptability by the consumers. Products processed by extrusion, such as those expanded by frying (pellets), have high carbohydrate content, and its enrichment with protein can favor its nutritional aspect. This study aimed to use the whey protein concentrate (WPC) in combination with corn grits in the preparation of pellets. Absolute density, density of expanded pellets, color, crispness index, and pellet sensory acceptance were determined. For the absolute density, contents from 5% to 17% produced denser non-expanded pellets. The higher the WPC content and the temperature of the extruder, the higher the density of the expanded pellets. The crispness index was not altered by the protein content and by the extruder temperature. In the sensory analysis, the preferred samples were the ones with lower WPC levels (5%). We concluded that higher WPC values in the pellets formulation increased their density, but did not alter color and texture, as well as small WPC levels did not affect the acceptance of snacks.

scholarly journals Does habitat structure influence capture probabilities? A study of reptiles in a eucalypt forest

2009 ◽  
Vol 36 (6) ◽  
pp. 509 ◽  
Author(s):  
Michael D. Craig ◽  
Andrew H. Grigg ◽  
Mark J. Garkaklis ◽  
Richard J. Hobbs ◽  
Carl D. Grant ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Vegetation Structure ◽  
Habitat Structure ◽  
Pitfall Traps ◽  
Total Removal ◽  
Habitat Types ◽  
Jarrah Forest ◽  
Future Studies ◽  
Eucalypt Forest ◽  
Structural Variables

Pitfall traps are commonly used to examine differences in reptile communities among habitat types and disturbance regimes that differ in structure. However, capture rates and probabilities may be influenced by habitat structure, which invalidates comparisons of relative abundance among habitat types. To assess whether pitfall traps provide accurate reflections of density and whether habitat structure affects capture probabilities, we trapped at six sites in various jarrah-forest habitat types in south-western Australia, then intensively searched 150-m2 total-removal plots around each pitfall grid to obtain absolute densities of reptiles. Pitfall captures were significantly correlated with numbers on total-removal plots for Hemiergis initialis and Lerista distinguenda, indicating that pitfall traps provided accurate reflections of density for these species. Capture probabilities of H. initialis and L. distinguenda and all reptiles combined showed no significant correlations with any structural variables, indicating that capture probabilities were consistent across sites. We conclude that trapping provided accurate estimates of relative abundance for some species and that capture probabilities were not influenced by vegetation structure. Because many studies use trapping to estimate abundances among habitat types, we encourage researchers to investigate how vegetation structure influences capture probabilities, so that general patterns can be determined; we also suggest improvements for any future studies.

Daily partitioning of summer habitat and use of space by the snowshoe hare in southern boreal forest

1992 ◽  
Vol 70 (11) ◽  
pp. 2178-2183 ◽  
Author(s):  
Jean Ferron ◽  
Jean-Pierre Ouellet
Keyword(s):  
Habitat Structure ◽  
Ground Cover ◽  
Time Of Day ◽  
Snowshoe Hare ◽  
Feeding Period ◽  
Habitat Types ◽  
Use Of Space ◽  
High Utilization ◽  
Vegetation Species ◽  
Resting Period

We investigated daily partitioning of summer habitat and use of space by the snowshoe hare (Lepus americanus) by means of radiotelemetry. Two periods corresponding to low and high activity were considered: resting during daytime and feeding at dawn and dusk. Areas used during the feeding and resting periods overlapped within each home range. During the feeding period, males occupied larger areas than during the resting period, but females did not. Vegetation characteristics were compared between 3 groups of plots corresponding to sites used during the feeding and resting periods and to low-utilization areas. Microhabitat characteristics differed between high-utilization and low-utilization sites, with mature conifer stands and areas with sparse hardwood understory characterizing low-utilization sites. Furthermore, the degree of utilization was related to habitat structure, not to vegetation species composition. Hares were also located more often in ecotones between different habitat types. During the feeding period, hares utilized sites with a greater ground cover of herbs and a lesser cover of ligneous plants, humus, and moss, and with a greater canopy closure, than during the resting period. Hares frequently utilized dense understory during both periods. These results do not support the predictions of Belovsky's model, based on thermal physiology, of snowshoe hare habitat selection according to the time of day.

Habitat selection by muskrats in experimental marshes undergoing succession

1994 ◽  
Vol 72 (4) ◽  
pp. 675-680 ◽  
Author(s):  
William R. Clark
Keyword(s):  
Habitat Selection ◽  
Water Depth ◽  
Plant Succession ◽  
Habitat Types ◽  
Wetland Succession ◽  
Wetland Complex ◽  
Density Dependent Habitat Selection ◽  
Different Levels ◽  
Selection Of

I analyzed habitat selection by muskrats (Ondatra zibethicus) in relation to density and plant succession in an experimental wetland complex flooded to three different levels: normal (long-term average elevation), medium (30 cm above normal), and high (60 cm above normal) at Delta, Manitoba. Locations where muskrats were trapped or built lodges were superimposed on vegetation types and water depth, in a geographic information system, to determine habitat selection. More than 60% of all individuals were captured in stands of Scirpus, Scolochloa, or Typha, and muskrats significantly avoided areas with water < 1 cm that were dominated by annuals and Hordeum. Muskrats preferred Typha and Scirpus stands for lodges, although some lodges were built in Scolochloa and Phragmites. Water depth at lodges averaged 38 cm, and > 90% of lodges were located in water ≥ 10 cm. Tall dense emergent growth trapped the most snow, resulting in the ice being less thick. Muskrats first captured in Typha or Scirpus stands gained significantly more mass during winter than did those captured in all other habitat types. As emergent vegetation changed and muskrat population density increased, the selection of habitat such as Typha in moderately deep water changed less than did the selection of habitat in shallow water or of those dominated by Scolochloa or sparse Scirpus. These data confirm density-dependent habitat selection by muskrats and suggest that spatial complexity induced by wetland succession is important in muskrat population dynamics.

Sign in / Sign up

Export Citation Format

Share Document