scholarly journals Susceptibility of Wiseana species to diflubenzuron and implications for field applications

2000 ◽  
Vol 53 ◽  
pp. 430-435 ◽  
Author(s):  
C.M. Ferguson

Porina control using diflubenzuron is popular due to its low cost and benign environmental effects The level of control in Otago and Southland however can be variable and may be associated with species diversity in the region In this investigation larvae of Wiseana cervinata W copularis W jocosa and W mimica were exposed to diflubenzuron in two laboratory bioassays All species were killed with small larvae killed more quickly than large There were only minor differences in susceptibility between species Adult flights at three sites showed variation in the main flight period suggesting that larvae in pasture in autumn would cover a wide size range This was confirmed by field sampling The timing and frequency of diflubenzuron applications should be considered in conjunction with the phenology of adult flight and subsequent larval development and climatic conditions affecting larval survival

1981 ◽  
Vol 32 (1) ◽  
pp. 93 ◽  
Author(s):  
J Kowarsky ◽  
AH Ross

A two-part study was made of fish movement past the Fitzroy River barrage at Rockhampton. Queensland. to assess the feasibilities of routes other than that through the simple pool and weir fishway situated at the barrage, and to monitor fish passage upstream through the fishway by placing a V-trap cage immediately above the fishway exit. Neither of the alternative routes to the fishway, namely via the inundated floodplain or under open barrage gates, appeared to be feasible pathways for fish to move to areas above the barrage. Sixteen species of fish over a relatively wide size range were found to pass through the fishway. Greatest species diversity. and rates of passage of particular species, occurred in the summer months. Variation in levels of the tidal tailwater and the headwater, which could be controlled to some extent by raising or lowering the barrage gates, influenced the numbers, sizes and species of fish passing through the fishway. It is concluded that while there is a need for facilitating fish movement upstream past the barrage. the present fishway does not seem to be particularly effective in this regard. Structural and management changes to the fishway which may improve its efficiency are proposed.


Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 514
Author(s):  
Zonglei Liang ◽  
Christopher H. Dietrich ◽  
Wu Dai

Xestocephalus Van Duzee is among the most common and widespread genera of Cicadellidae in the temperate and tropical regions of the world. In the present study, 205 specimens of the genus Xestocephalus were collected in Thailand, whereas only a single species of the genus was recorded previously using Malaise trap field sampling, studied by comparative morphology. Seventeen species were recognized, including twelve new species: X. binarius sp. nov., X. chrysanthemum sp. nov., X. cowboyocreus sp. nov., X. densprint sp. nov., X. dimiprocessus sp. nov., X. exproiecturus sp. nov., X. gracilus sp. nov., X. limpidissimus sp. nov., X. malleus sp. nov., X. nonattribus sp. nov., X. recipinams sp. nov., and X. tenusis Liang sp. nov. Four species were recorded in Thailand for the first time: Xestocephalus abyssinicus Heller and Linnavuori, Xestocephalus asper Linnavuori, Xestocephalus ishidae Matsumura, and Xestocephalus toroensis Matsumura. Detailed morphological descriptions of all 17 species are given; photographs of external habitus and male genitalia of the species from Thailand are provided. A checklist of species of the genus is also given, and a key to all Thailand Xestocephalus species is also provided.


2021 ◽  
Vol 13 (5) ◽  
pp. 2836
Author(s):  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Muhammad Bilal ◽  
Hadeed Ashraf ◽  
Muhammad Farooq ◽  
...  

Poultry are one of the most vulnerable species of its kind once the temperature-humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor-based air-conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low-cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko-Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature-humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature-humidity-velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew-point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.


2019 ◽  
Author(s):  
Johannes Brändle ◽  
Norbert Kunert

Abstract Tree autotrophic respiratory processes, especially stem respiration or stem CO2 efflux (Estem), are important components of the forest carbon budget. Despite the efforts to investigate the controlling processes of Estem in the last years a considerable lack in our knowledge remains on the abiotic and biotic drivers affecting Estem dynamics. It has been strongly advocated that long-term measurements would shed light into those processes. The expensive scientific instruments needed to measure gas exchange has prevented from applying Estem measurements on a larger temporal and spatial scale. Here, we present an automated closed dynamic chamber system based on inexpensive and industrially broadly applied CO2 sensors reducing the costs for the sensing system to a minimum. The CO2 sensor was cross-calibrated with a commonly used gas exchange system in the laboratory and in the field, and we found very good accordance of these sensors. We tested the system under harsh tropical climatic conditions, characterized by heavy tropical rainfall events, extreme humidity, and temperatures, in a moist lowland forest in Malaysia. We recorded Estem of three Dyera costulata trees with our prototype over various days. The variation of Estem was large among the three tree individuals and varied by 7.5-fold. However, clear diurnal changes in Estem were present in all three tree individuals. One tree showed high diurnal variation in Estem and the relationship between Estem and temperature was characterized by a strong hysteresis. The large variations found within one single tree species highlights the importance of continuous measurement to quantify ecosystem carbon fluxes.


2010 ◽  
Vol 47 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Stanisław Seniczak ◽  
Anna Seniczak

Oribatid mites (Acari, Oribatida) of various habitats in southern Andalusia (Spain)Oribatid mites were investigated in some habitats (litter under cypress, pine and larch trees, and patches of grasses, mosses and lichens) in southern Andalusia (Spain) in August 2005. The studied communities of oribatid mites were rather poor in terms of abundance and species diversity. The density of mites in cypress litter from the mountains (Granada, Ronda) was distinctly higher than in the coastal area (Benalmádena), which was probably caused by climatic conditions. The Oribatida achieved the highest density in grassy patches in Granada, but most species occurred in cypress litter from Ronda. Among oribatid species,Oribatula frisiaereached the highest density; alsoO. tibialisandHaplochthonius simplexwere relatively abundant. Some species of Oribatida were rich in juveniles, but the age structure of species greatly depended on the kind of litter.


Author(s):  
Lachlan Mcleay ◽  
C.G. Alexander

Combining the use of scanning electron microscopy and microcinematography with functional and behavioural observations has clarified many aspects underlying the feeding processes of the small planktonic sergestid shrimp Acetes sibogae australis. In captivity Acetes sibogae australis is an opportunistic feeder that uses four principal feeding modes to capture a wide size range of prey: Artemia nauplii (<0.33 mm), copepods (<1mm) and moribund Acetes (up to 25 mm). Prey capture is effected by combined actions of the first three pairs of pereiopods and the third maxillipeds before transfer to the more dorsal second maxillipeds. The second maxillipeds are the principal appendages used in securing, manipulating, sorting and rejecting prey before insertion into the vicinity of the inner mouthparts.


1980 ◽  
Vol 12 (1) ◽  
pp. 165-171 ◽  
Author(s):  
Thomas R. Harris ◽  
Harry P. Mapp

Climatic conditions in semiarid regions like the Oklahoma Panhandle result in wide fluctuations in rainfall, dryland crop yields, and returns to agricultural producers in the area. Irrigated crop production increases peracre yields and significantly reduces fluctuations in yields and net returns.Irrigated production of food and fiber in the Oklahoma Panhandle has developed rapidly during the past three decades, increasing from 11,500 to 385,900 acres since 1950 (Schwab). The primary source of irrigation water in the area is the Ogallala Formation, an aquifer underlying much of the Great Plains region. Until the past couple of years, the presence of relatively low cost natural gas led producers to expand irrigated production and apply high levels of water to crops irrigated in the area.


2020 ◽  
pp. 152808372092473 ◽  
Author(s):  
Suchart Siengchin ◽  
Pawinee Boonyasopon ◽  
Vajja Sadanand ◽  
Anumakonda Varada Rajulu

In the present work, nanocomposite cellulose fabrics with in situ generated silver nanoparticles were prepared by bioreduction method employing aqueous dispersion of low-cost natural turmeric powder as a reducing agent and different concentrated aqueous AgNO3 as source solutions. The prepared nanocomposite cellulose fabrics were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and antibacterial tests. The nanocomposite cellulose fabrics had roughly spherical silver nanoparticles in the size range of 41–130 nm with an overall average of 78 nm. The X-ray analysis indicated the generation of both silver nanoparticles and Ag2O nanoparticles in the nanocomposite cellulose fabrics. The nanocomposite cellulose fabrics retained the generated AgNPs even after repeated detergent washings. The prepared nanocomposite cellulose fabrics exhibited excellent antibacterial activity against both the Gram-negative and Gram-positive bacteria and hence can be considered as antibacterial hospital-bed materials, apparels, etc.


2011 ◽  
Vol 63 (4) ◽  
pp. 660-665 ◽  
Author(s):  
R. J. Craggs ◽  
S. Heubeck ◽  
T. J. Lundquist ◽  
J. R. Benemann

This paper examines the potential of algae biofuel production in conjunction with wastewater treatment. Current technology for algal wastewater treatment uses facultative ponds, however, these ponds have low productivity (∼10 tonnes/ha.y), are not amenable to cultivating single algal species, require chemical flocculation or other expensive processes for algal harvest, and do not provide consistent nutrient removal. Shallow, paddlewheel-mixed high rate algal ponds (HRAPs) have much higher productivities (∼30 tonnes/ha.y) and promote bioflocculation settling which may provide low-cost algal harvest. Moreover, HRAP algae are carbon-limited and daytime addition of CO2 has, under suitable climatic conditions, the potential to double production (to ∼60 tonnes/ha.y), improve bioflocculation algal harvest, and enhance wastewater nutrient removal. Algae biofuels (e.g. biogas, ethanol, biodiesel and crude bio-oil), could be produced from the algae harvested from wastewater HRAPs, The wastewater treatment function would cover the capital and operation costs of algal production, with biofuel and recovered nutrient fertilizer being by-products. Greenhouse gas abatement results from both the production of the biofuels and the savings in energy consumption compared to electromechanical treatment processes. However, to achieve these benefits, further research is required, particularly the large-scale demonstration of wastewater treatment HRAP algal production and harvest.


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