Evaluation of the actual evapotranspiration model of decomposition at a subalpine surface coal mine

1986 ◽  
Vol 64 (1) ◽  
pp. 35-38
Author(s):  
W. F. J. Parsons ◽  
D. M. Durall ◽  
D. Parkinson

Percentages of original dry mass lost annually and single exponential decay rates (k) for timothy (Phleum pratense L.) leaf litter decomposing on three reclaimed subalpine mine spoil plots (7, 3, and 1 years old) in Alberta, Canada, were compared with values predicted using generalized equations devised by Meentemeyer on the basis of an annual regional average of actual evapotranspiration (Thornthwaite) and a site-specific value (Christiansen). Measured decay rates on the more heavily vegetated plots (3 and 7 years old) were similar to k values predicted using Christiansen actual evapotranspiration values, while the decay rate on the plot with the least amount of vegetation cover (1 year old) was much greater than k values predicted using Christiansen or Thornthwaite actual evapotranspiration values. The actual evapotranspiration model severely underestimated annual percentage mass losses, regardless of whether Thornthwaite or Christiansen actual evapotranspiration values were used.

2020 ◽  
Vol 2020 (4) ◽  
pp. 39-45
Author(s):  
Valentina Korovina ◽  
Nikolay Kozlov ◽  
Tamara Komkova

The research was carried out in the field at the Central experimental base of the Federal Williams Re¬search Center. The object of research was 12 samples of wild-growing meadow timothy grass. Samples were sown according to the scheme of a standard collection nursery. All studies and observations were carried out on the herbage of the 2nd and 3rd year of life. Statistical processing of results of researches of meadow timothy indicates a low level of variation in the main morphological and physiological characte¬ristics. Only by the number of vegetative shoots have the coefficient of variation reach 35.8%. Samples 416 and 419 were distinguished by precocity, samples 406 and 419 by the height of plants during flower¬ing, sample 412 by the number of generative shoots, and sample 412 by the yield of air-dry mass. Sam¬ples 409 and 414 were distinguished by the length of the sultan, and the weight of seeds — 414 and 415. Nine reliable correlations were found at the significance level 05 and 01. However, all of them are related to the yield of the number of generative and vegetative shoots. Using the binomial equation, the experi¬mentally obtained variability of dry mass yield from the number of generative and vegetative shoots by 93.1% is described. The optimal productivity of meadow timothy grass stand for generative shoots in the area of 550–600 shoots, and vegetative ones — in the area of 320–350 shoots per square meter. Analysis of remoteness and kinship between samples showed the presence of 2 clusters (genetically different quality groups), which can be used for combinational ability selection and fixing of selection-valuable features and properties.


1989 ◽  
Vol 9 (4) ◽  
pp. 1507-1512 ◽  
Author(s):  
H Zhu ◽  
H Conrad-Webb ◽  
X S Liao ◽  
P S Perlman ◽  
R A Butow

All mRNAs of yeast mitochondria are processed at their 3' ends within a conserved dodecamer sequence, 5'-AAUAAUAUUCUU-3'. A dominant nuclear suppressor, SUV3-I, was previously isolated because it suppresses a dodecamer deletion at the 3' end of the var1 gene. We have tested the effects of SUV3-1 on a mutant containing two adjacent transversions within a dodecamer at the 3' end of fit1, a gene located within the 1,143-base-pair intron of the 21S rRNA gene, whose product is a site-specific endonuclease required in crosses for the quantitative transmission of that intron to 21S alleles that lack it. The fit1 dodecamer mutations blocked both intron transmission and dodecamer cleavage, neither of which was suppressed by SUV3-1 when present in heterozygous or homozygous configurations. Unexpectedly, we found that SUV3-1 completely blocked cleavage of the wild-type fit1 dodecamer and, in SUV3-1 homozygous crosses, intron conversion. In addition, SUV3-1 resulted in at least a 40-fold increase in the amount of excised intron accumulated. Genetic analysis showed that these phenotypes resulted from the same mutation. We conclude that cleavage of a wild-type dodecamer sequence at the 3' end of the fit1 gene is essential for fit1 expression.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Toshihiro Horiguchi ◽  
Kayoko Kawamura ◽  
Yasuhiko Ohta

AbstractIn 2012, after the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) that followed the Tohoku earthquake and tsunami in March 2011, no rock shell (Thais clavigera; currently recognized as Reishia clavigera; Gastropoda, Neogastropoda, Muricidae) specimens were found near the plant from Hirono to Futaba Beach (a distance of approximately 30 km). In July 2016, however, rock shells were again found to inhabit the area. From April 2017 to May 2019, we collected rock shell specimens monthly at two sites near the FDNPP (Okuma and Tomioka) and at a reference site ~ 120 km south of the FDNPP (Hiraiso). We examined the gonads of the specimens histologically to evaluate their reproductive cycle and sexual maturation. The gonads of the rock shells collected at Okuma, ~ 1 km south of the FDNPP, exhibited consecutive sexual maturation during the 2 years from April 2017 to May 2019, whereas sexual maturation of the gonads of specimens collected at Hiraiso was observed only in summer. The consecutive sexual maturation of the gonads of the specimens collected at Okuma might not represent a temporary phenomenon but rather a site-specific phenotype, possibly caused by specific environmental factors near the FDNPP.


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