An alternative way in electrical resistivity prospection: the quasi-null arrays

2019 ◽  
Vol 220 (3) ◽  
pp. 1463-1480
Author(s):  
S Szalai ◽  
K Szokoli ◽  
E Prácser ◽  
M Metwaly ◽  
M Zubair ◽  
...  

SUMMARY While traditional geoelectric array configurations, such as the Wenner–Schlumberger or the dipole–dipole, can provide very good images of 1-D or robust 2-D structures, they are not sufficiently sensitive to those inhomogeneities that have a small effect on the surface electrical potential distribution. The detection and description of such inhomogeneities become possible by applying quasi-null arrays, which provide very small (close to zero) signals above a homogeneous half-space. The imaging properties of the members of an array series containing such arrays, the so-called γ11n arrays (n = 1–7), are demonstrated and compared to those of the most popular traditional arrays. Although the field applicability of the quasi-null arrays has been heavily questioned, it was demonstrated by our quasi-field analogue modelling experiments. The quasi-field tests also validated all of the numerical modelling results as follows: (1) many or all of the γ11n arrays were able to detect prisms and vertical sheets located at depths larger than those detectable by traditional geoelectric arrays, including the optimized Stummer configuration; (2) the horizontal resolution of the γ11n arrays proved to be better than the horizontal resolution of traditional arrays; (3) with n increasing, the γ11n arrays proved to be less sensitive to 1-D, but more sensitive to 2-D bodies. In case of high n values, the γ11n arrays may even be entirely insensitive to any 1-D structure. On the basis of the quasi-field experiments, γ11n arrays are expected to be very efficient to indicate bodies, or variations in time that only have a small impact on the surface electrical potential distribution (e.g. caves, mines, tunnels, tubes, cables, fractures, dykes), or small changes in the subsurface conditions (monitoring of dams or waste deposits). Data acquisition by both a traditional and a γ11n array, individual inversion of their data, and a joint interpretation of the results are recommended to obtain both a robust image and fine details of the subsurface.

Weed Science ◽  
1979 ◽  
Vol 27 (5) ◽  
pp. 497-501 ◽  
Author(s):  
C. D. Boyette ◽  
G. E. Templeton ◽  
R. J. Smith

An indigenous, host-specific, pathogenic fungus that parasitizes winged waterprimrose [Jussiaea decurrens(Walt.) DC.] is endemic in the rice growing region of Arkansas. The fungus was isolated and identified asColletotrichum gloeosporioides(Penz.) Sacc. f.sp. jussiaeae(CGJ). It is highly specific for parasitism of winged waterprimrose and not parasitic on creeping waterprimrose (J. repensL. var.glabrescensKtze.), rice (Oryza sativaL.), soybeans [Glycine max(L.) Merr.], cotton (Gossypium hirsutumL.), or 4 other crops and 13 other weeds. The fungus was physiologically distinct from C.gloeosporioides(Penz.) Sacc. f. sp.aeschynomene(CGA), an endemic anthracnose pathogen of northern jointvetch[Aeschynomene virginica(L.) B.S.P.], as indicated by cross inoculations of both weeds. Culture in the laboratory and inoculation of winged waterprimrose in greenhouse, growth chamber and field experiments indicated that the pathogen was stable, specific, and virulent in a wide range of environments. The pathogen yielded large quantities of spores in liquid culture. It is suitable for control of winged waterprimrose. Winged waterprimrose and northern jointvetch were controlled in greenhouse and field tests by application of spore mixtures of CGJ and CGA at concentrations of 1 to 2 million spores/ml of each fungus in 94 L/ha of water; the fungi did not damage rice or nontarget crops.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1452
Author(s):  
Raluca-Maria Pârlici ◽  
Aurel Maxim ◽  
Stefania Mirela Mang ◽  
Ippolito Camele ◽  
Lucia Mihalescu ◽  
...  

Organic berry plantations have been gaining popularity among farmers during recent years. Even so, farmers experience serious challenges in disease control management, which is a concern in organic farming. Phragmidiumrubi-idaei (DC) P. Karst is the pathogen responsible for blackberry and raspberry rust disease, one of the most present and active diseases in plantations. The antifungal certified products found on the organic farming market offer the opportunity for an efficient control strategy over plant pathogens in fruit shrub plantations. In this study, 5 natural based products—namely Altosan, Mimox, Canelys, Zitron, and Zeolite—were tested for their fungistatic effect over P. rubi-idaei. The experiments were carried out under laboratory conditions, performing observations over the impact of organic products, used at different concentration levels, on rust conidia germination. Moreover, field experiments were conducted in order to evaluate the efficiency of different treatments for rust control on raspberry (‘Polka’, ‘Veten’ and ‘Heritage’) and blackberry (‘Thorn Free’, ‘Chester’ and ‘Loch Ness’) varieties. Data analysis based on ANOVA tests showed significant differences between the tested variants and the control sample at p < 0.001. Furthermore, LSD test confirmed differences between all substances tested (p < 0.005). The natural products Canelys (formulated with cinnamon) and Zytron (based on citrus extract) have proven the highest inhibitory capacity for conidia germination during in vitro tests registering values of 80.42% and 78.34%, respectively. The same high inhibitory rates against rust pathogen were kept also in the field tests using the same two natural-based products mentioned earlier. In addition, outcomes from this study demonstrated that Zeolite is not recommended for raspberry or blackberry rust control.


2013 ◽  
Vol 103 (6) ◽  
pp. 665-674 ◽  
Author(s):  
Á. Egri ◽  
M. Blahó ◽  
D. Száz ◽  
G. Kriska ◽  
J. Majer ◽  
...  

AbstractHost-seeking female tabanid flies, that need mammalian blood for the development of their eggs, can be captured by the classic canopy trap with an elevated shiny black sphere as a luring visual target. The design of more efficient tabanid traps is important for stock-breeders to control tabanids, since these blood-sucking insects can cause severe problems for livestock, especially for horse- and cattle-keepers: reduced meat/milk production in cattle farms, horses cannot be ridden, decreased quality of hides due to biting scars. We show here that male and female tabanids can be caught by a novel, weather-proof liquid-filled black tray laid on the ground, because the strongly and horizontally polarized light reflected from the black liquid surface attracts water-seeking polarotactic tabanids. We performed field experiments to reveal the ideal elevation of the liquid trap and to compare the tabanid-capturing efficiency of three different traps: (1) the classic canopy trap, (2) the new polarization liquid trap, and (3) the combination of the two traps. In field tests, we showed that the combined trap captures 2.4–8.2 times more tabanids than the canopy trap alone. The reason for the larger efficiency of the combined trap is that it captures simultaneously the host-seeking female and the water-seeking male and female tabanids. We suggest supplementing the traditional canopy trap with the new liquid trap in order to enhance the tabanid-capturing efficiency.


Author(s):  
Yu. I. Buryak ◽  
A. A. Skrynnikov

The article is devoted to the substantiation of the procedure for testing complex technical systems to assess the probability of performing the task, taking into account a priori data obtained from the results of modeling, field tests of components and prototypes, operation of analogues, etc. The conditions for the formation of a combined sample consisting of field experiments and experiments counted on the results of modeling are justified. Data uniformity is checked using the Student's criterion. The minimum volume of full-scale tests is determined by the requirement of equality of the amount of Fischer information about the estimated parameter obtained during full-scale tests and at the expense of a priori data A strategy for conducting field experiments is proposed, in which the required quality of evaluating the probability of completing the task is achieved with the minimum possible number of field experiments. At the first stage, a series of experiments with a volume equal to half of the required sample size is performed. At the second stage, the experiments are conducted sequentially with an assessment after each experiment of the requirements for the amount of information about the evaluated parameter and for the uniformity of data. Experiments are terminated when the specified requirements are met, and then a combined sample is formed, which is used to evaluate the probability of the system performing the task. A model example is considered. The estimation of the gain in the number of experiments performed at different probability values was carried out.


1967 ◽  
Vol 15 (1) ◽  
pp. 21-30
Author(s):  
C.H. Henkens ◽  
K.W. Smilde

In pot and field tests MnSO4 and the frits FTE Z 4 (13 % Mn), HZ 1 (15.9 % Mn) and HZ 17 (21 % Mn) increased reducible soil Mn for at least 1 1/2-2 years. Mn content of pasture increased four-fold in the first cut after application of 400 kg/ha MnSO4 but sharply decreased in later cuts and became negligible by the second year. 400 kg/ha HZ 17 did not affect pasture Mn. In peas 400 kg of soil- or foliar applied MnSO4 controlled marsh spot better than 800 kg HZ 1; spraying at the middle and again at the end of the blooming stage gave the best control. With sugar beet, soil dressings of MnSO4, HZ 1 and HZ 17 equally increased yield, sugar production and leaf Mn, and decreased incidence of Mn deficiency. When the rates of these fertilizers were increased from 100, 179 and 86 kg respectively to 400, 714 and 343 kg, sugar production was not significantly improved; leaf Mn and incidence of deficiency symptoms responded to the higher Mn rates. Soil application was rather better than foliar treatment. No treatment controlled Mn deficiency throughout the entire season. The % of Mn-deficient plants was related, negatively, to leaf and reducible soil Mn, but not to yield. Soil-applied Mn did not control gray spot in oats or increase yields but sprayed Mn did. (Abstract retrieved from CAB Abstracts by CABI’s permission)


1969 ◽  
Vol 28 (1) ◽  
pp. 22-34
Author(s):  
Bernardo G. Capó

A new method of performing field experiments with relatively small numbers of treatments is described. The requirement to be fulfilled by the layouts of such field tests is specified and examples of possible designs for a 5-treatment experiment are illustrated. The theory of the procedure of calculation is discussed and a numerical example of said calculations is furnished in connection with the interpretation of a fertilizer experiment performed with cotton.


2021 ◽  
Vol 12 (5) ◽  
pp. 6393-6414

A scaling-up study integrating experimental and field experiments was managed to explore the most appropriate catalysis method to assist industries in getting rid of the Congo Red (CR) dye from industrial wastewater. The adsorption potential of kaolinite (K) modified by Ulva Lactuca (UL) was evaluated to eliminate CR dye from aqueous solutions. The novel kaolinite/alga nanocomposite (KUL) was synthesized following steps of the wet impregnation method and then subjected to characterization using different techniques. The newly reported KUL nanocomposite shows a significant increase in adsorption ability higher than that of K and UL. To research different experimental factors' effects, batch experiments were evaluated, and each of the kinetics/isotherms of CR adsorption were explored either. The CR removal% is clearly affected by catalyst dose, working temperature, and pH value with high percentage. The best temperature for CR adsorption onto KUL is 400C at pH>7. CR adsorption on KUL following the first-order diffusion model, while K and UL appeared to follow two different kinetic adsorption models depending on the CR concentration. Moreover, the field tests (scaling-up experiments) revealed optimistic results with 91% efficiency for KUL nano-adsorbents in eliminating mixed dyes from industrial wastewater, which means the foundation of novel environmentally benign nano-adsorbents to help in industrial wastewater recycling.


1989 ◽  
Vol 3 (2) ◽  
pp. 307-312 ◽  
Author(s):  
Howard F. Harrison ◽  
Richard L. Fery

Preliminary evaluation of 11 pepper genotypes indicated a high degree of variability in bentazon tolerance. ‘Bohemian Chile’ and ‘Santanka’ hot pepper tolerated bentazon similarly in subsequent greenhouse and field experiments. Yields or shoot fresh weights of these two cultivars were not reduced by up to 9.0 kg ai/ha bentazon in the field. ‘Keystone Resistant Giant’ sweet pepper was more susceptible to bentazon compared to the tolerant cultivars, but it was more tolerant than the highly susceptible cultivar, ‘Sweet Banana’. An F1hybrid of Keystone Resistant Giant and Santanka tolerated bentazon better than Keystone Resistant Giant but slightly less than Santanka. Thus, bentazon tolerance in this genotype is genetically transferrable, and increasing bentazon tolerance through conventional plant breeding techniques may be possible.


Weed Science ◽  
1980 ◽  
Vol 28 (1) ◽  
pp. 59-63 ◽  
Author(s):  
C. G. McWhorter ◽  
J. R. Williford

Field experiments were conducted to determine optimum nozzle settings for applying glyphosate [N-(phosphonomethyl)glycine] in the recirculating sprayer for postemergence control of johnsongrass [Sorghum halepense(L.) Pers.] in soybeans [Glycine max(L.) Merr.]. Herbicide sprays were directed across the row to johnsongrass growing taller than soybeans in July and August. Herbicide not sprayed on johnsongrass was trapped and reused. Glyphosate at 0.56, 1.12, and 2.24 kg/ha applied with commercially available 25° spray nozzles provided johnsongrass control and soybean yields equal to those following applications with specialized uniform droplet nozzles. Glyphosate at 1.7 kg/ha applied in the recirculating sprayer using only one nozzle per row provided control of johnsongrass equal to or better than that from applications made with two, three, or four nozzles per row. Soybean yield following application of glyphosate at 1.7 kg/ha with one nozzle per row was equal to yields obtained following its application with two, three, or four nozzles per row, with or without surfactant at 0.1% in spray solutions. Soybean yield was higher with four nozzles per row than with one nozzle per row when 0.5% surfactant was included in spray solutions. Soybean injury was lower and yield was higher when glyphosate was applied in the recirculating sprayer rather than over-the-top with a conventional sprayer. Glyphosate at 1.12 kg/ha applied in the recirculating sprayer caused more injury to ‘Hill’ and ‘Bragg’ than to ‘Forrest’ or ‘Tracy’ soybeans.


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