Combined effect of wood moisture content,drill bit rotational speed and feed rate on drilling resistance measurements in Norway spruce (Picea abies (L.) Karst.)

ABSTRACT

An IML-RESI PD 400 drilling tool and a standard spade drill bit (IML System GmbH, Wiesloch, Germany) were used to study the combined effect of wood moisture content (MC), drill bit rotational speed and feed rate on drilling resistance (DR) and feeding force (FF). Tests were made with Norway spruce (Picea abies (L.) Karst.) conditioned in a normal climate (20°C/65% RH), at 20°C/95% RH, vacuum-pressure impregnated in water, and oven-dried. Rotational speeds and feed rates had an impact on feed rate per cutting edge for the major cutting edge of the drill bit which was used for correlation with DR and FF for various MC. Impact of MC on DR and FF depended on rotational speeds and feed rates of the drill bit. For feed rates per cutting edge less than 0.09?mm, DR was higher for water saturated (WS) specimens. Negligible differences between DR for various MC were found for feed rates per cutting edge between 0.09 and 0.15?mm. DR was higher at low MC for feed rates per cutting edge which were higher than 0.15?mm. FF extremely increased in conditioned (20°C/95% RH) and WS specimens at feed rates per cutting edge less than 0.1?mm.     

Soils of sinkholes on the western macroslope of the southern Urals: Properties, catenary relationships, and regional specificity

A series of microcatenas on the slopes of sinkholes were studied on the western macroslope of the southern Urals in the Shulgan-Tash Reserve. The morphological, chemical, physical, and physicochemical characteristics of the soils were analyzed. In order to reveal their regional specificity, the soils of the sinkholes under broadleaved forests in the southern Urals were compared with analogous soils under the northern taiga of the Belomorsk-Kuloi Plateau. It was shown that the full-profile vertically differentiated soils in the upper parts of the microcatenas are replaced by weakly developed and slightly differentiated soils in the lower parts of the microcatenas crossing sinkholes of different diameters in both natural zones.     

Effect of the Geological Factor on Polyarenes in Soils

The study, generalization, and comparative analysis of data on the content and composition of polyarenes have been performed for the soils subjected to the impact of the following factors: (1) approach of bituminous material to the surface along the fault zone from the deep layers of sedimentary rocks with the formation of bituminous sandstones and asphalt lenses (Bakhilovo asphalt deposit, Zhiguli dislocations, Samara region); (2) periodical discharge of large amounts of volcanic tephra into the atmosphere resulting in the formation of pyroclastic deposits (near the Avacha Volcano, Kamchatka region); (3) increased geodynamic activity within the area of the recent blocky structure of the earth crust, where a spontaneous upward flux of fluids into the soil is possible (Istra morphostructural node, Moscow region); and (4) high fumarolic activity resulting in the impact of hot water and vapor on the surrounding soils (Golovnin caldera, Island Kunashir, Kuril region). It has been found that the considered manifestations of geological factors can be arranged into the following increasing order: (a) exposure of volcanic tephra as a parent rock (20 ng/g); (b) increased hydrodynamic and fumarolic activity (85–90 ng/g); and (c) penetration of asphalt into the sedimentary rocks (4800 hg/g). According to the diversity of polyarenes identified in the soils, the considered situations form the following increasing series: (a) 9 out of 11 identified polycyclic aromatic hydrocarbons (PAHs) are found in the area of increased geodynamic activity and in the region of volcanic tephra fallouts; (b) 10 PAHs are identified in the asphalt deposit; and (c) all 11 PAHs are identified in the area of fumarolic activity.     

Application of Natural Humates for Remediating Contaminated Urban Soils and Stimulating Plant Growth

Long-term laboratory and microfield experiments have revealed the effective doses of humates for their use as detoxifiers of urban soils. The developed original technique allowed us to modify the commercial product Ekstra by fundamentally changing the ratio of amphiphilic fractions of humic substances. Field tests of new Ekstra growth showed its high efficacy as a plant growth stimulator and antistress preparation, which makes it possible to mitigate (or greatly reduce) the toxic effects of various pollutants on plants in contaminated areas.     

Assessment of the physical quality of a soddy-podzolic soil under the impact of the long-term application of fertilizers

The physical quality of a soddy-podzolic soil in an experiment with the long-term application of mineral fertilizers has been evaluated on the basis of data on the soil porosity and the soil shrinkage capacity. The degree of soil degradation under the impact of mineral fertilizers is inversely proportional to the biomass of grown crops.     

Laboratory analytical methods for the determination of the hydrocarbon status of soils (a review)

Laboratory analytical methods suitable for the determination of the hydrocarbon status of soils (a specific soil characteristic involving information on the total content and qualitative features of soluble (bitumoid) carbonaceous substances and individual hydrocarbons (polycyclic aromatic hydrocarbons, alkanes, etc.) in bitumoid, as well as the composition and content of hydrocarbon gases) have been considered. Among different physicochemical methods of study, attention is focused on the methods suitable for the wide use. Luminescence-bituminological analysis, low-temperature spectrofluorimetry (Shpolskii spectroscopy), infrared (IR) spectroscopy, gas chromatography, chromatography–mass spectrometry, and some other methods have been characterized, as well as sample preparation features. Advantages and limitations of each of these methods are described; their efficiency, instrumental complexity, analysis duration, and accuracy are assessed.     

Indicative capacity of NDVI in predictive mapping of the properties of plow horizons of soils on slopes in the south of Western Siberia

The informativeness of NDVI for predictive mapping of the physical and chemical properties of plow horizons of soils on different slope positions within the first (280–310 m a.s.l.) and second (240–280 m a.s.l.) altitudinal steps has been examined. This index is uninformative for mapping soil properties in small hollows, whose factual width is less than the Landsat image resolution (30 m). In regression models, NDVI index explains 52% of variance in the content of humus; 35 and 24% of variance in the contents of total and nitrate nitrogen; 19 and 29% of variance in the contents of total and available phosphorus; 25 and 50% of variance in the contents of exchangeable calcium and manganese; and 30 and 29% of variance in the contents of fine silt and soil water, respectively. On the basis of the models obtained, prognostic maps of the soil properties have been developed. Spatial distribution patterns of NDVI calculated from Landsat 8 images (30-m resolution) serve as the cartographic base and the main indicator of the soil properties. The NDVI values and the contents of humus, physical clay (<0.01 mm) and fine silt particles, total and nitrate nitrogen, total phosphorus, and exchangeable calcium and manganese in the soils of the first altitudinal step are higher than those in the soils of the second altitudinal step. An opposite tendency has been found for the available phosphorus content: in the soils of the second altitudinal step and the hollow, its content is higher than that in the soils of the first altitudinal step by 1.8 and 2.4 times, respectively. Differences in the pH of soil water suspensions, easily available phosphorus, and clay in the soils of the compared topographic positions (first and second altitudinal steps and the hollow) are statistically unreliable.     

Orders in the soil classification system of Russia: Taxonomic distance as a measure of their adequate identification

Taxonomic distances between pairs of soil orders in the Russian soil classification system have been calculated using a methodology suggested for calculation of taxonomic distances between the Reference Soil Groups in the international soil classification system (WRB). Basing on the data obtained, some proposals for the development of the Russian soil classification system have been formulated. Most of the orders are characterized by considerable taxonomic distances between them, and their identification in the classification system is doubtless. Small taxonomic distances are characteristic of the following pairs of orders: organo-accumulative and structural-metamorphic soils, hydrometamorphic soils and lithozems, and cryometamorphic and eluvial soils. Therefore, criteria for defining some orders, and/or profile formulas for some soil types composing the orders may be revised. The comparison of taxonomic distances between soil orders in the Russian system and between Reference Soil Groups in the international system allows us to suggest their certain similarity.     

Effect of Soil Degradation and Remediation in Technogenic Barrens on the Uptake of Nutrients and Heavy Metals by Plants in the Kola Subarctic

Eurasian Soil Science - To assess the state of plants and their response to changes in soil properties, the elemental composition of leaves of widespread and pollution-tolerant species Betula...     

Soils of karst sinkholes in the southeast of the Belomorsk-Kuloi Plateau

A series of soil-geochemical microcatenas on the slopes of karst sinkholes in the southeast of the Belomorsk-Kuloi Plateau have been studied. Several types of karst sinkholes have been specified according to the character of surface deposits overlying karstic rocks. The morphological characteristics of the soils of these microcatenas and their chemical and physicochemical properties have been analyzed. On the slopes of the sinkholes, various variants of iron-illuvial podzols and texturally differentiated soils with superimposed profiles of podzols in their upper coarse-textured parts are developed. It is shown that the combinations of the particular factors of soil formation in karst landscapes can both reduce and enhance the vertical differentiation of the soil profiles forming in the sinkholes of different types, which is manifested in the properties of these soils and in the specific of their catenary variations by the elements of the karst topography.