scholarly journals Comparison of long-term changes in size and longevity of bee colonies in mid-west Japan and Maui with and without exposure to pesticide, cold winters, and mites

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9505
Author(s):  
Toshiro Yamada ◽  
Kazuko Yamada

Four long-term field experiments in mid-west Japan (Shika) made it clear that extinction of colonies exposed to neonicotinoid was much higher than for colonies exposed to organophosphates. The incidence of hive death for of organophosphate-exposed and control (pesticide-free) colonies was similar. We conducted a field experiment in Maui for 271 days using the same pesticides (dinotefuran: 0.2 ppm, clothianidin: 0.08 ppm, fenitrothion: 1 ppm) as used in Shika with the honeybee, Apis mellifera, colonies without mites. Numbers of adult bees, capped brood, mites and other hive parameters were accurately counted on photographs of combs and on the inside of the hives. All six neonicotinoid (dinotefuran & clothianidin)-exposed colonies failed during the experiment. One of three organophosphate (fenitrothion)-exposed colonies and one of the three control colonies also failed. The findings from Maui, where colonies displayed no mites, provides evidence from Shika, with mites, that neonicotinoids are more hazardous to honeybee colonies than organophosphates. The apparent longevity of honeybee colonies on Maui was estimated by numbers of adult bees and capped brood using a mathematical model previously proposed. Seasonal changes in longevity on Maui differ greatly from changes at Shika, the latter showing distinct seasonal variation. Longevity on Maui remains nearly constant throughout the year with wide variations. At Shika, it increases drastically in winter, by six- to ten fold more than the other seasons. Differences seem to depend on the existence of cold winters and the length of flowering seasons. In a perpetually hospitable environment, small changes in conditions can be sensitively reflected in apparent longevity. Examining wide variations in apparent longevity that are seemingly incoherent, we recognized several differences in apparent longevity between neonicotinoid-exposed and organophosphate-exposed colonies: The colony that failed in after organophosphate-exposure colony group exhibited the longest apparent longevity and the fewest number of newly capped brood, as also was the case in control colonies. Extended longevity when few brood are newly produced is reasonable to maintain the colony from a physiological point of view. Extension of apparent longevity is not seen in neonicotinoid-exposed colonies when the number of newly capped brood is fewer. This finding suggests that neonicotinoid pesticides may inhibit normal apian physiology.

2015 ◽  
Author(s):  
Toshiro Yamada ◽  
Yasuhiro Yamada ◽  
Kazuko Yamada

SummaryWe have previously examined the impact of neonicotinoid pesticides, dinotefuran and clothianidin, on honeybee Apis mellifera colonies in long-term field experiments when they were simultaneously administered through both vehicles of sugar syrup and pollen paste (Yamada et al., 2012). The independent effect of a pesticide through two vehicles has not been studied in our previous work. In this paper, we investigated the independent impact of dinotefuran through each of the two vehicles. We confirmed that dinotefuran intake per bee until colony extinction due to administration through pollen paste (DF-TIPP) was roughly one-fifth as much as that through sugar syrup (DF-TISS). The intake was largely independent of dinotefuran concentration. We considered the possibility of DF-TIPP per bee as an indicator to assess the impact of persistent pesticide on a honeybee colony in a practical apiary.This work has replicated the finding that a honeybee colony has dwindled away to nothing after assuming an aspect of a colony collapse disorder (CCD) by administration of the neonicotinoids dinotefuran and clothianidin in our previous work, regardless of the vehicles. In addition, a failure in wintering was observed in case of administration of dinotefuran with the lowest concentration in this work even if the colony appeared vigorous before winter.We can infer that a CCD and a failure in wintering may have the same roots of chronic toxicity of neonicotinoids under conditions of low concentrations due to the persistency and high toxicity which are characteristic of them.


2021 ◽  
Vol 126 ◽  
pp. 126263
Author(s):  
Mario Fontana ◽  
Gilles Bélanger ◽  
Juliane Hirte ◽  
Noura Ziadi ◽  
Saïd Elfouki ◽  
...  

2003 ◽  
Vol 49 (5) ◽  
pp. 465-483 ◽  
Author(s):  
Katalin Debreczeni ◽  
Martin Körschens

2018 ◽  
Vol 218 ◽  
pp. 158-170 ◽  
Author(s):  
Theresa Zicker ◽  
Sabine von Tucher ◽  
Mareike Kavka ◽  
Bettina Eichler-Löbermann

Author(s):  
Francisco Javier Garcia Marco

Thesauri are considered as an optimum between maximum ontological modelling (best knowledge mapping) and minimal alphabetic ordering (less expensive access). From this point of view a swift history of its evolution is provided. The recent evolutions in Internet searching are also analysed from this perspective. In this context, there is an immediate role for thesauri to ensure interoperability and feed up the new Internet semantic engines; and in the long term as a simple semantic user interface for resource discovery and navigation, which ensures proper transparency and control by the user who wants to take the effort to supervise and analyse its search processes. It is proposed that better devices for ensuring semantic sorting are provided when necessary, and that a distributed hub for thesauri interconnection is provided, perhaps using the existent big open Internet semantic facilities, as Wikipedia


2017 ◽  
pp. 836-853
Author(s):  
N. Suchkova ◽  
E. Darakas ◽  
J. Ganoulis ◽  
Y. Vergeles

In this work the suitability of several plant species for phytoremediation under natural and artificially installed conditions was studied. Brassica napus, Medicago sativa, Zea mays, Triticum aestivum, and Hordeum vulgare were grown in pots with sewage sludge from Sindos Main WWTP in Thessaloniki and from Sindos Industrial WWTP in Thessaloniki, Greece. The first series of experiments included comparing measurements of various parameters for the above mentioned plants and the sludge to those for control samples (the same plants growing in compost). It was shown that shoot growth was less reduced in T. aestivum and H. vulgare than in the other plant species studied. B. napus had lower germination tax, followed by M. sativa with the lowest germination tax. Generally B. napus, giving less biomass production than Z. mays and T. aestivum, is characterised by a higher ability to accumulate heavy metals like Cd, Cu, Ni, Pb, Zn, Cr, As and Hg. The second series of experiments included comparing measurements of various parameters of B. napus grown in sludge and treated each 7 days with metal solutions of Ni, Zn and Pb containing 10-2mg/l, 10-4mg/l, 10-6mg/l of each metal, to those for control plants treated with double distilled water. Results showed that shoot growth of B. napus were increased at treatments with lower concentrations of metals (10-6 mg/l) and control (treatment with d-distilled water). At the same time uptake of metal ions was increased with the concentration of the solution, i.e. at higher concentrations (10-2 mg/l). It is truly for Pb and Zn, transfer coefficient TC of which (indicates a plant’s potential to concentrate a metal) was quite high 15 % and 7 % correspondingly. It was noticed that B. napus has high ability to accumulate Cr, from the other hand it did not accumulate Ni (at present case).


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