scholarly journals Effects of Malaise trap spacing on species richness and composition of terrestrial arthropod bulk samples

2021 ◽  
Vol 5 ◽  
Author(s):  
Dirk Steinke ◽  
Thomas WA Braukmann ◽  
Laura Manerus ◽  
Allan Woodhouse ◽  
Vasco Elbrecht
Keyword(s):  
Species Richness ◽  
Field Experiments ◽  
Collection Efficiency ◽  
Malaise Trap ◽  
Number Of Factors ◽  
Large Numbers ◽  
Set Up ◽  
Taxonomic Groups ◽  
A Site ◽  
Malaise Traps

The Malaise trap is a popular device for assessing diverse terrestrial arthropod communities because it collects large samples with modest effort. A number of factors influence its collection efficiency, placement being one of them. For instance, when designing larger biotic surveys using arrays of Malaise traps we need to know the optimal distance between individual traps that maximises observable species richness and community composition. We examined the influence of spacing between Malaise traps by metabarcoding samples from two field experiments at a site in Waterloo, Ontario, Canada. For one experiment, we used two trap pairs deployed at weekly increasing distances (3 m increments from 3 to 30 m). The second experiment involved a total of 10 traps set up in a row at 3 m distance intervals for three consecutive weeks. Results show that community similarity of samples decreases over distance between traps. The amount of species shared between trap pairs drops considerably at about 18 m trap-to-trap distance. This change can be observed across all major taxonomic groups and for two different habitat types (grassland and forest). Large numbers of OTUs found only once within samples cause rather large dissimilarity between distance pairs even at close proximity. This could be caused by a large number of transient species from adjacent habitats which arrive at the trap through passive transport, as well as capture of rare taxa, which end up in different traps by chance.

scholarly journals Effects of Malaise trap spacing on species richness and composition of terrestrial arthropod bulk samples

2020 ◽  
Author(s):  
D Steinke ◽  
TWA Braukmann ◽  
L Manerus ◽  
A Woodhouse ◽  
V Elbrecht
Keyword(s):  
Species Richness ◽  
Field Experiments ◽  
Collection Efficiency ◽  
Malaise Trap ◽  
Number Of Factors ◽  
Large Numbers ◽  
Set Up ◽  
Taxonomic Groups ◽  
A Site ◽  
Malaise Traps

AbstractThe Malaise trap has gained popularity for assessing diverse terrestrial arthropod communities because it collects large samples with modest effort. A number of factors that influence collection efficiency, placement being one of them. For instance, when designing larger biotic surveys using arrays of Malaise traps we need to know the optimal distance between individual traps that maximises observable species richness and community composition. We examined the influence of spacing between Malaise traps by metabarcoding samples from two field experiments at a site in Waterloo, Ontario, Canada. For one experiment, we used two trap pairs deployed at weekly increasing distance (3m increments from 3 to 27 m). The second experiment involved a total of 10 traps set up in a row at 3m distance intervals for three consecutive weeks.Results show that community similarity of samples decreases over distance between traps. The amount of species shared between trap pairs shows drops considerably at about 15m trap-to-trap distance. This change can be observed across all major taxonomic groups and for two different habitat types (grassland and forest). Large numbers of OTUs found only once within samples cause rather large dissimilarity between distance pairs even at close proximity. This could be caused by a large number of transient species from adjacent habitat which arrive at the trap through passive transport, as well as capture of rare taxa, which end up in different traps by chance.

scholarly journals Improving the design of piles driven in chalk through the ALPACA research project

2019 ◽  
pp. 2 ◽  
Author(s):  
Richard James Jardine ◽  
Róisín Marie Buckley ◽  
Byron Walter Byrne ◽  
Stavroula Kontoe ◽  
Ross Alexander McAdam ◽  
...  
Keyword(s):  
Field Experiments ◽  
Field Testing ◽  
Field Work ◽  
Test Site ◽  
Offshore Wind ◽  
Driven Piles ◽  
Lateral Resistance ◽  
Large Numbers ◽  
Port Facilities ◽  
Set Up

Chalk is present under large areas of NW Europe as a low-density, porous, weak carbonate rock. Large numbers of offshore wind turbines, bridges and port facilities rely on piles driven in chalk. Current European practice assumes ultimate shaft resistances that appear low in comparison with the Chalk’s unconfined compression strength and CPT cone resistance ranges and can impact very significantly on project economics. Little guidance is available on pile driveability, set-up or lateral resistance in chalk, or on how piles driven in chalk can sustain axial or lateral cyclic loading. This paper describes the ALPACA (Axial-Lateral Pile Analysis for Chalk Applying multi-scale field and laboratory testing) project funded by EPSRC and Industry that is developing new design guidance through comprehensive field testing at a well-characterised low-to-medium density test site, supported by analysis of other tests. Field experiments on 36 driven piles, sixteen of which employ high resolution fibre-optic strain gauges, is supported by advanced laboratory and in situ testing, as well as theoretical analysis. The field work commenced in October 2017 and was largely complete in May 2019.

scholarly journals Diversity of Calliphoridae (Diptera) in Brazil's Tinguá Biological Reserve

2006 ◽  
Vol 66 (1a) ◽  
pp. 95-100 ◽  
Author(s):  
C. R. Marinho ◽  
L. S. Barbosa ◽  
A. C. G. Azevedo ◽  
M. M. C. Queiroz ◽  
M. A. Valgode ◽  
...  
Keyword(s):  
Rio De Janeiro ◽  
Meteorological Data ◽  
Large Numbers ◽  
Representative Species ◽  
Set Up ◽  
Chicken Viscera ◽  
A Site ◽  
Pathogenic Agents ◽  
And Control ◽  
Biological Reserve

The Calliphoridae are flies of great ecological, medical and sanitary importance because they are decom-posers of organic matter, mechanical vectors of pathogenic agents, and causers of myiasis. This paper attempts to ascertain the diversity of Calliphoridae in the Tinguá Biological Reserve and correlate meteorological data (temperature, relative humidity of the air, and precipitation) with the occurrence of these flies. The study was conducted at a site in the Tinguá Biological Reserve, located in the municipality of Nova Iguaçu, state of Rio de Janeiro, Brazil. Four traps were set up using chicken viscera as bait. The experiment was conducted over the period of May 2001 to April 2002, with two monthly collections. The captured flies were killed with ether and conserved in 70% alcohol and identified in the Laboratory of Diptera Studies (UNIRIO) and the Laboratory of Vector Insect Biology and Control (FIOCRUZ), both headquartered in the city of Rio de Janeiro, RJ, Brazil. A total of 1,987 insects were captured, 37.5% belonging to the family Calliphoridae, 29.4% to Muscidae, 16.0% to Sarcophagidae, and 17.1% to other families. The most representative species found was Phaenicia eximia (47.0%), followed by Hemilucilia semidiaphana (23.6%), Mesembrinella bellardiana (13.7%), Hemilucilia segmentaria (7.5%), Chloroprocta idioidea (4.9%), Chrysomya albiceps (1.2%), Chrysomya megacephala (0.9%), Phaenicia sericata (0.6%), Eumesembrinella sp. (0.5%), and Chrysomya putoria (0.1%). Large numbers of Calliphoridae were noted in May, June, September and January, coinciding with low rainfall and an average temperature of 21.8 to 27.0 °C. A negative correlation was found between the number of Calliphoridae captured and meteorological factors.

Muscidae (Diptera) diversity in Churchill, Canada, between two time periods: evidence for limited changes since the Canadian Northern Insect Survey

2012 ◽  
Vol 144 (1) ◽  
pp. 29-51 ◽  
Author(s):  
Anaïs K. Renaud ◽  
Jade Savage ◽  
Robert E. Roughley
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Malaise Trap ◽  
Collecting Methods ◽  
Insect Survey ◽  
Time Periods ◽  
Trap Catches ◽  
Survey Protocol ◽  
Pan Traps ◽  
Malaise Traps

AbstractA survey of muscid flies from Churchill, Manitoba, Canada, in 2007 yielded 155 species. Some components of species richness and composition of this contemporary assemblage were compared with those of a historical (pre-1965) assemblage, and the contribution of the three collecting methods used in the 2007 survey protocol was evaluated. Estimates of species richness indicated that Malaise traps yielded more species than did pan traps or sweep netting, and that species composition did not differ significantly between Malaise trap and pan trap catches. These results suggest that Malaise traps and sweep netting are adequate methods to survey northern Muscidae. We report little difference in estimated species richness and composition between time periods for material collected by sweep netting. When all material from the 2007 survey was pooled, 87% of the pre-1965 species were collected again in 2007. Most nonoverlapping species between time periods were rare in samples and (or) collected by different methods, suggesting a failure to detect as the most likely explanation for their absence in one assemblage. Nevertheless, the proportion of aquatic and semiaquatic species of Spilogona Schnabl was more than twice as high in the list of species not recovered in 2007 than in the pre-1965 assemblage.

Eels Under Standing Wave Conditions

1982 ◽  
Vol 40 ◽  
pp. 492-495
Author(s):  
O.L. Krivanek ◽  
J. TaftØ
Keyword(s):  
Standing Wave ◽  
Wave Conditions ◽  
Set Up ◽  
A Site ◽  
Complex Crystal

It is well known that a standing electron wavefield can be set up in a crystal such that its intensity peaks at the atomic sites or between the sites or in the case of more complex crystal, at one or another type of a site. The effect is usually referred to as channelling but this term is not entirely appropriate; by analogy with the more established particle channelling, electrons would have to be described as channelling either through the channels or through the channel walls, depending on the diffraction conditions.

Prediction of root damaging during mechanical shaking of fruit trees

2014 ◽  
Vol 10 (1) ◽  
pp. 1-15
Author(s):  
Z. Láng
Keyword(s):  
Field Experiments ◽  
Calculated Data ◽  
Fruit Trees ◽  
List Type ◽  
Structure Model ◽  
Root Damage ◽  
Set Up ◽  
Simple Tree ◽  
The Given ◽  
Cherry Trees

The possible effect of shaker harvest on root damage of 10-year-old cherry trees was studied on a simple tree structure model. The model was composed of elastic trunk and rigid main roots, the ends of which were connected to the surrounding soil via springs and dumping elements. Equations were set up to be able to calculate the relation between shaking height on the trunk and strain in the roots. To get the data for root break and their elongation at different shaking heights on the trunk, laboratory and field experiments were carried out on cherry trees and on their roots. Having evaluated the measured and calculated data it could be concluded that root damage is to be expected even at 3.6% strain and the risk of it increases with increased trunk amplitudes, i.e.with the decrease of shaking heightat smaller stem diameters (i.e. in younger plantation), andif the unbalanced mass of the shaker machine is too large for the given tree size.

Assemblage Patterns of Hymenoptera at Different Elevations of Gunung Datuk, Rembau

2017 ◽  
Vol 14 (2) ◽  
pp. 1 ◽  
Author(s):  
Noor Nasuha Abd Aziz ◽  
Siti Khairiyah Mohd Hatta ◽  
Idris Abd Ghani ◽  
Saiyid Jalaluddin Saiyid Shaifuddin
Keyword(s):  
Species Richness ◽  
Diversity Index ◽  
High Elevation ◽  
Significant Difference ◽  
Index Site ◽  
Evenness Index ◽  
Abundance And Diversity ◽  
Richness Index ◽  
Paired T Test ◽  
Malaise Traps

A study on abundance and diversity of Hymenoptera was conducted in Gunung Datuk, Rembau. Samplings were conducted from November 2014 to February 2015 using six Malaise traps. Three traps were placed at Site 1 at 700m height for high elevation and the remaining traps were placed at Site 2 at 200m height for low elevation. A total number of 221 Hymenopteran were collected which consist of nine families namely Ichneumonidae, Formicidae, Braconidae, Bethylidae, Evaniidae, Tiphiidae, Vespidae, Pompilidae and Apidae. In this study, 93 individuals were obtained from Site 1, comprising nine families and 43 morphospecies while 127 individuals were obtained from Site 2 with nine families and 45 morphospecies. Formicidae was the most dominant family collected from both sites with a total of 104 individuals while the least family recorded was Apidae with only one individual. Shannon’s Weiner Diversity Index (H’) showed Site 1 had the higher diversity value with H’ = 3.17 compared to Site 2 with value H’ = 3.12. For Evenness Index, Site 1 had higher value compared to Site 2 with E’ = 0.84 and E’ = 0.82 respectively. Moreover, for Margalef Richness Index, Site 1 recorded R’ = 9.24 while site two recorded R’ = 9.08 which concluded that Site 1 had higher species richness compared to Site 2. Paired t-test showed that both sites had no significant difference with p>0.05. Overall study showed that the diversity and abundance of Hymenoptera in Gunung Datuk were low since the value of H’ is less than 3.50.

scholarly journals Effects of disk tillage on soil condition, crop yield and weed infestation

2011 ◽  
Vol 48 (No. 1) ◽  
pp. 20-26
Author(s):  
M. Birkás ◽  
T. Szalai ◽  
C. Gyuricza ◽  
M. Gecse ◽  
K. Bordás
Keyword(s):  
Winter Wheat ◽  
Crop Yield ◽  
Field Experiments ◽  
Soil Layer ◽  
Soil Condition ◽  
Perennial Weeds ◽  
Weed Infestation ◽  
Set Up ◽  
Different Levels

This research was instigated by the fact that during the last decade annually repeated shallow disk tillage on the same field became frequent practice in Hungary. In order to study the changes of soil condition associated with disk tillage and to assess it is consequences, long-term tillage field experiments with different levels of nutrients were set up in 1991 (A) and in 1994 (B) on Chromic Luvisol at Gödöllö. The effects of disk tillage (D) and disk tillage combined with loosening (LD) on soil condition, on yield of maize and winter wheat, and on weed infestation were examined. The evaluation of soil condition measured by cone index and bulk density indicated that use of disking annually resulted in a dense soil layer below the disking depth (diskpan-compaction). It was found, that soil condition deteriorated by diskpan-compaction decreased the yield of maize significantly by 20 and 42% (w/w), and that of wheat by 13 and 15% (w/w) when compared to soils with no diskpan-compaction. Averaged over seven years, and three fertilizer levels, the cover % of the total, grass and perennial weeds on loosened soils were 73, 69 and 65% of soils contained diskpan-compaction.

scholarly journals The pitfalls of biodiversity proxies: Differences in richness patterns of birds, trees and understudied diversity across Amazonia

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Camila D. Ritter ◽  
Søren Faurby ◽  
Dominic J. Bennett ◽  
Luciano N. Naka ◽  
Hans ter Steege ◽  
...  
Keyword(s):  
Species Richness ◽  
Large Scale ◽  
Spatial Scales ◽  
Local Environment ◽  
Life Forms ◽  
Taxonomic Group ◽  
Diversity Gradients ◽  
Richness Patterns ◽  
Taxonomic Groups ◽  
Micro Organisms

AbstractMost knowledge on biodiversity derives from the study of charismatic macro-organisms, such as birds and trees. However, the diversity of micro-organisms constitutes the majority of all life forms on Earth. Here, we ask if the patterns of richness inferred for macro-organisms are similar for micro-organisms. For this, we barcoded samples of soil, litter and insects from four localities on a west-to-east transect across Amazonia. We quantified richness as Operational Taxonomic Units (OTUs) in those samples using three molecular markers. We then compared OTU richness with species richness of two relatively well-studied organism groups in Amazonia: trees and birds. We find that OTU richness shows a declining west-to-east diversity gradient that is in agreement with the species richness patterns documented here and previously for birds and trees. These results suggest that most taxonomic groups respond to the same overall diversity gradients at large spatial scales. However, our results show a different pattern of richness in relation to habitat types, suggesting that the idiosyncrasies of each taxonomic group and peculiarities of the local environment frequently override large-scale diversity gradients. Our findings caution against using the diversity distribution of one taxonomic group as an indication of patterns of richness across all groups.

scholarly journals An Alpine Malaise trap

2018 ◽  
Vol 2 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Shasta Claire Henry ◽  
Peter B. McQuillan ◽  
James B. Kirkpatrick
Keyword(s):  
Low Cost ◽  
Sampling Period ◽  
Rough Terrain ◽  
Light Weight ◽  
Malaise Trap ◽  
Remote Locations ◽  
Insect Trap ◽  
Rapid Deployment ◽  
Alpine Environments ◽  
Malaise Traps

The Southernmost region of Australia, the island of Tasmania, is also the most mountainous, with large areas of rugged alpine environments. This entomological frontier offers a distinct suite of insects for study including many endemic taxa. However, harsh weather, remote locations and rough terrain represent an environment too extreme for many existing insect trap designs. We report here on the design and efficacy of a new Alpine Malaise Trap (AMT), which can be readily hybridised with several other common insect trapping techniques. Advantages of the design include its light weight and portability, low cost, robustness, rapid deployment and long autonomous sampling period. The AMT was field tested in the Tasmanian highlands (AUST) in 2017. A total of 16 orders were collected. As expected, samples are dominated by Diptera. However, the trap also collected a range of flightless taxa including endemic and apterous species, Apteropanorpatasmanica – closest relative of the boreal, snow scorpionflies (Boreidae). Combined and compared with other trap types the Alpine Malaise Traps captured less specimens but of a greater diversity than passive sticky traps, while drop traps captured less specimens but a greater diversity than AMT. The statistical potential of the catch is discussed.

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