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1.
Electrophoretic gliadin components are inherited as highly stable blocks of linked components. Multiple allelism of blocks controlled by polygenic loci of six gliadin-coding chromosomes has been revealed. The allelic states of these loci are interrelated with the variability of grain. The regularities discovered permit the use of gliadin polymorphism for estimation of genotype properties in breeding programs.  相似文献   
2.
We propose a new method for estimating fish density using catches obtained by gillnets of given mesh size. This method builds on work for estimating the number of fish approaching a gillnet by modelling the fish movement that leads to a gillnet encounter. The theoretical framework is developed, and the method is tested on catch data for cod Gadus morhua and Dolly Varden Salvelinus malma to demonstrate how the method can be applied. The method relies on knowledge of geometric properties of the net, and morphological and behavioural properties of the fish, so we explore the sensitivity of the estimates to some of these parameters. Estimates are most sensitive to the morphological parameter of the angle the mouth is open while swimming and largely invariant to estimates of uncertain parameters like maximum number of fish that can be caught by the particular net.  相似文献   
3.

Purpose

The volume of dust deposition on the soil surface in Moscow is big enough and make several tens of grams per square meter annually. The role of dust as a soil-forming material is especially high in places with practically no other soil parent materials. It is necessary to consider solid atmospheric precipitation as a parent soil material in urban conditions and its impact on soil properties.

Materials and methods

Samples of two soil bodies were taken near two major highways of Moscow, and airborne solid deposit samples were collected from the roadside barrier in summer and from plant leaves after snowmelt. The fallout samples were studied by methods used for soil because of its silicate matrix (Si~30 % total). Main complex characteristics of samples were obtained by chemical analysis and with a scanning electron microscope with energy-dispersive X-ray spectrometer. Bulk elemental composition, available phosphorus and potassium, carbonates, organic carbon and oil hydrocarbon contents, pH, redox potential, magnetic susceptibility, and particle-size distribution of dust and soils were determined.

Results and discussion

Near the highways, where the process of dust transfer is activated, there are possibilities of dust inclusion into soil and formation of new soil horizons on these deposits. Pedofeatures are formed during a very short period of time. The soil-forming processes are connected with both soil organic matter and mineral compound transformation. Chemical properties of the studied soils correspond to those of usual Moscow soil horizons and dust samples studied previously by Prokofyeva et al. (2011) and Prokof’eva et al. (2015). It was established that atmospheric solid aerosol imports organic carbon, carbonates, and other salts; pollutants such as oil hydrocarbons; and heavy metals into the soil. Airborne deposits influence soil physical properties by enriching the soil with clay and coarse silt fractions.

Conclusions

Investigation of dust deposit composition provides data for characterizing material being continuously deposited on the urban soil surface. The atmospheric fallouts together with construction waste and natural rocks provide the common geochemical properties of urban soils.
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