AGRIS - 

2015

S. I. Bartsev | A. A. Pochekutov

A possible method for experimental determination of parameters of the previously proposed continual mathematical model of soil organic matter transformation is theoretically considered in this paper. The previously proposed by the authors continual model of soil organic matter transformation, based on using the rate of matter transformation as a continual scale of its recalcitrance, describes the transformation process phenomenologically without going into detail of microbiological mechanisms of transformation. Thereby simplicity of the model is achieved. The model is represented in form of one differential equation in firstorder partial derivatives, which has an analytical solution in elementary functions. The model equation contains a small number of empirical parameters which generally characterize environmental conditions where the matter transformation process occurs and initial properties of the plant litter. Given the values of these parameters, it is possible to calculate dynamics of soil organic matter stocks and its distribution over transformation rate. In the present study, possible approaches for determination of the model parameters are considered and a simple method of their experimental measurement is proposed. An experiment of an incubation of chemically homogeneous samples in soil and multiple sequential measurement of the sample mass loss with time is proposed. An equation of time dynamics of mass loss of incubated homogeneous sample is derived from the basic assumption of the presented soil organic matter transformation model. Thus, fitting by the least squares method the parameters of sample mass loss curve calculated according the proposed mass loss dynamics equation allows to determine the parameters of the general equation of soil organic transformation model.

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Directory of Open Access Journals - Sweden

2015

Khomenko L.O. | Sorochenko G.V.

Background. Rationalizing of the choice of the most effective means for exogenous prevention, especially during secondary mineralization, will increase cariesresistance of tooth enamel. Objective - in vitro study of changes of just erupted permanent teeth enamel surface under the influence of exogenous means for caries prevention containing different calcium compounds. Methods. For the study we used 35 enamel samples of permanent teeth that had erupted within the same term (premolars of 11-13 years old children, less than 6 months after eruption). 5 samples were the control group before the experiment. 30 samples were randomly divided equally into three groups (10 samples in each group) and stored in boxes with artificial saliva. Enamel samples of the first group were treated with cream “TOOTH MOUSSE” (10% casein phosphopeptide - amorphous calcium phosphate), samples of the second group were treated with gel “R.O.C.S. Medical minerals” (calcium glycerophosphate, magnesium chloride, xylitol). Samples of the first and second groups were treated at the beginning of the research and 3, 6 and 9 months later during 10 days, twice a day for 30 minutes. Samples of the third group were the control and were not treated. Investigation of the enamel surface was performed at the beginning of the experiment, after 6 and 12 months. The structure of the samples surface was studied at the equator zone with the scanning electron microscope. Results. At the beginning of the experiment signs of insufficient mineralization were observed on the surface of the enamel samples of the control group. After 12 months of treatment with cream with casein phosphopeptide - amorphous calcium phosphate and gel with calcium glycerophosphate, surface of the enamel samples of both groups had the signs of an increased mineralization due to the long-term preservation of a layer of additional chemical compounds. Conclusion. The surface of the permanent teeth enamel immediately after the eruption, and during next 12-18 months has visible signs of insufficient mineralization. Under the influence of exogenous means for caries prevention with casein phosphopeptide - amorphous calcium phosphate and calcium glycerophosphate for 12 months visible signs of increased mineralization level of enamel surface appear. Citation: Khomenko LO, Sorochenko GV. [The in vitro investigation of morphological changes of permanent teeth enamel surface under the influence of exogenous means for caries prevention containing different calcium compounds]. Morphologia. 2015;9(1):65-70. Ukrainian.

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Directory of Open Access Journals - Sweden

2015

Eremin, D.I. | Akhtyamova, A.A.

Field experiments were conducted in the Tyumen region on leached heavy loamy chernozem. The decomposition intensity of straw of spring wheat grown in a crop rotation with NPK calculated for planed yield of 3-6 t/ha was estimated. Loss in straw weight was recorded after, 1, 2 and 4 months. Straw decomposition in an unfertilized variant reaches a maximum (40.6-44.3%) throughout the whole plowing layer. Increasing the mineral nutrition results in additional flow of soil moisture, which has a negative influence on the cellulose-decomposing microflora, a decrease in the variant with NPK for yield of 3.0 and 4.0 t/ha is 33% of the original weight. High agricultural background improves a nitrogen regime in the soil, which leads to increasing of the mineralization process of straw in the plowing layer up to 42% in 4 months of exposure. During the first half of the growth season the upper layer of 20 cm is the most active; it develops optimal conditions for straw mineralization - the decline in the variants with NPK reached 30%. In the variants with a maximum agricultural background the speed of straw decomposition increases in the layer of 20-30 cm, for 4 months the decline exceeded 40% of the original weight. In variants with maximum fertilizer saturation (the planned yield 5.0 and 6.0 t/ha of grain) throughout the vegetation period the enhancement of mineralization of straw in the arable layer was observed. The loss for 4 months of exposure reached 47% of the original weight. The weight of straw disposed in the variants with NPK under the yield 4.0 t/ha of grain for the whole exposition period decreased not more than by 20%, and in the variants with planned yield of grain 5.0 and 6.0 t/ha reached 40% of the original weight. The improvement of the mineral nutrition level increases the period of active straw mine realization, which under the forest steppe zone of Trans-Urals may enhance the deficit of plant residues in arable chernozem. | Полевые опыты проводили в Тюменской обл. на черноземе выщелоченном тяжелосуглинистом. Оценивали интенсивность разложения соломы яровой пшеницы, выращенной в севообороте на фонах NPK, рассчитанных на планируемую урожайность 3-6 т/га. Убыль массы соломы фиксировали через 1, 2 и 4 мес. Разложение соломы на неудобренном варианте достигает максимальных значений (40,6-44,3%) по всему пахотному слою. Повышение уровня минерального питания приводит к дополнительному расходу почвенной влаги, что негативно отражается на целлюлозоразлагающей микрофлоре, убыль на варианте с NPK под урожай 3,0 и 4,0 т/га составляет 33% от исходной массы. Повышенный агрофон способствует улучшению азотного режима в почве, что приводит к усилению процессов минерализации соломы в пахотном слое до 42% за 4 мес. экспозиции. В первую половину вегетации наиболее активным является верхний (20 см) слой, где складывается оптимальные условия для минерализации соломы – убыль на вариантах с внесением NPK достигла 30%. На вариантах с максимальным агрофоном скорость разложения соломы возрастает в слое 20-30 см, за 4 мес. убыль превысила 40% относительно исходной массы. На вариантах с максимальной насыщенностью удобрениями (планируемая урожайность 5,0 и 6,0 т/га зерна) на протяжении всего вегетационного периода наблюдали усиление минерализации соломы в пахотном слое. Убыль за 4 мес. экспозиции достигала 47% от исходной массы. Масса соломы, расположенной на вариантах с NPK под урожай 4,0 т/га зерна за весь период экспозиции уменьшилась не более чем на 20%, а на вариантах с планируемой урожайностью зерна 5,0 и 6,0 т/га убыль достигла 40% от исходной массы. Повышение уровня минерального питания увеличивает период активной минерализации соломы, что в условиях лесостепной зоны Зауралья может усилить дефицит растительных остатков в пахотных черноземах.

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Central Scientific Agricultural Library - Russian Federation

2015

Osadchenko, I.M. | Gorlov, I.F. | Mosolova, N.I. | Nikolaev, D.V., Volga Research and Development Inst. of Production and Processing of Meat and Dairy Products, Volgograd

The new preservatives for feed technology have been under selection Sudan grass herbage (moisture content of 55-60%), a drought-resistant crop of widely cultivated in the Low Volga region, was the research target. The following mix was used as preservative: mineralized whey – a byproduct of whey electrolysis (diluted with water in the ratio of 1:3) and hydrous ammonia (30%) at a rate of 12 mL kg and 1 mL kg respectively. The preservation was carried out according to a known technology, including ensilaging chopped herbage of Sudan grass layer by layer with addition of the preservative followed by compaction, sealing and storage for 52 days. The preservative was not used in the control. The experimental silage sample revealed higher quality compared to the control. The experimental silage as compared to the control one contained more carotene by 2.8% (39.7 versus 36.9 mg/kg), lactic acid by 4% (87 versus 84, percent calculated from the sum of acids), crude protein by 0.2% (6,7 versus 6,5), crude fat by 0.3% (3.9 versus 3.6) and phosphorus by 0.1% (0.2 versus 0.1). The preservative proposed enables making silage of higher quality; the use of mineralized whey will improve environmental safety and expand the range of preservatives. | Проводили поиск новых консервантов для кормопроизводства. Для исследований была выбрана зелёная масса суданской травы (влажностью 55-60%) – засухоустойчивой культуры, широко возделываемой в Нижнем Поволжье. В качестве консерванта использовали смесь: минерализат – побочный продукт электролиза молочной сыворотки (после разведения водой в соотношение 1:3) и водный раствор (30%) аммиака с расходом 12 и 1 мл/кг соответственно. Консервирование проводили по известной технологии: загрузкой измельчённой зелёной массы суданки в ёмкость послойно с добавлением консерванта с последующим уплотнением, герметизацией и хранением в течение 52 сут. В контроле консервант не применяли. В опытном варианте получен силос более высокого качества по сравнению с контролем. При этом в опытном варианте в сравнении с контрольным содержалось больше каротина на 2,8% (39,7 против 36,9 мг/кг), молочной кислоты – на 4% (87 против 84, % от суммы кислот), сырого протеина – на 0,2% (6,7 против 6,5), сырого жира – на 0,3 (3,9 против 3,6), фосфора – на 0,1% (0,2 против 0,1). Предложенный консервант позволяет приготовить силос более высокого качества, использование минерализата сыворотки улучшит экологическую безопасность, расширит ассортимент консервантов.

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Central Scientific Agricultural Library - Russian Federation

2015

Nikitin, V.V. | Tyutyunov, S.I. | Voronin, A.N. | Solovichenko, V.D. | Navol'neva, E.V., Belgorod Research and Development Inst. of Agriculture

В длительных стационарных опытах в юго-западной части Центрально-Черноземного региона в течение 4 ротаций (20 лет) изучали влияние типа севооборота, способов основной обработки почвы, органических и минеральных удобрений и их сочетаний на динамику гумуса. Почва - чернозём типичный среднемощный малогумусный тяжелосуглинистый на лёссовидном суглинке. Исследования проводили в зернотравянопропашном, зернопропашном и зернопаропропашном 5-польных севооборотах с насыщением структуры посевных площадей пропашными культурами на уровне 20, 40 и 60% соответственно. Изучали несколько способов основной обработки почвы (вспашка, безтвальная и минимальная обработки) и систем удобрения сельскохозяйственных культур (органическая, минеральная и органо-минеральная) с внесением разных доз, рассчитанных на простое и расширенное воспроизводство плодородия чернозёмов. Наиболее сильное воздействие на содержание гумуса в почве оказали тип севооборота, внесение органических удобрений и посев многолетних трав. Применение минеральных удобрений в севооборотах по-разному влияло на величину этого показателя: в зернотравянопропашном севообороте с увеличением их доз наблюдался прирост гумуса (на 0,18-0,27%) с большими значениями при минимальной обработке почвы, а в пропашных севооборотах при внесении двойных доз минеральных удобрений отмечено снижение его содержания до 0,38%. В случае совместного использования органических и минеральных удобрений количество гумуса в почве в зернотравянопропашном севообороте повышалось от 0,63% при вспашке до 0,78% при минимальной обработке. Положительный баланс гумуса на делянках опыта без внесения удобрений отмечен только в зернотравянопропашном севообороте с содержанием в структуре посевных площадей 40% многолетних бобовых трав. Простое воспроизводство гумуса в севооборотах с насыщением пропашными культурами на уровне 40-60% наблюдали при внесении 8 т навоза на 1 га севооборотной площади, а расширенное - в варианте с 16 т/га. | In long-term stationary experiments in the southwest part of the Central Black Earth region during four rotations (20 years) the influence of the type of crop rotation, methods of tillage, organic and mineral fertilizers and their combinations on humus dynamics were studied. The soil of the test plot was typical black soil, middle thick, low-humus, heavy loamy on loess-like loam. The researches were carried out in grain-grass-row, grain-row and grain-fallow-row five-field crop rotations with saturation of sown area by row crops, respectively, 20, 40 and 60%. Several types of tillage (plowing, nonmoldboard and minimum cultivations) and fertilizer systems for crops (organic, mineral and organo-mineral) with application of different norms of fertilizers, calculated for the simple and expanded reproduction of soil fertility were studied. The type of crop rotation, application of organic fertilizers and sowing of perennial grasses had the strongest influence on the humus content. The application of mineral fertilizers in crop rotations had the different effect on level of this index: in grain-grass-row crop rotation with increased norms of them there was an increase in humus (by 0.18-0.27%) with large values at minimal cultivation, but in row crop rotations there was a decrease to 0.38% with application of two norms of mineral fertilizers. In the case of combined application of organic and mineral fertilizers, the humus content in the soil in grain-grass-row crop rotation was increased from 0.63% at ploughing to 0.78% with minimal processing. The positive balance of humus on test plots without fertilization was obtained only in grain-grass-row crop rotation with the content 40% of perennial legumes in the structure of sown area. Simple reproduction of humus in crop rotations with saturation 40-60% of row crops was obtained by application of 8 t of manure per 1 hectare of crop rotation area, and expanded one - in the variant with 16 t/ha of manure.

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Central Scientific Agricultural Library - Russian Federation