The Effects of Different Intensity of Thinning on the Development in Scots Pine (Pinus sylvestris L.) Stands in Kazakh Uplands

The search for more accurate methods of predicting the growth and development of forest stands became the most urgent task set for foresters of Kazakhstan to determine the permissible interventions in the natural course of the life of plantings, provide high durability and resilience in forests. The aim of the study was to identify the effects of diameter and density of Scots pine stands of Kazakh Uplands on their growth and productivity and the related productivity of single plantation stands taking into account the conditions of growth and development of internal factors as well as further study of the methodology for assessing the forestry cost-effectiveness and improvement thinning. To achieve this aim, effects of varied felling intensities on Scots pine stands were studied. The most common two forest types in upland Scots pine forests were chosen as permanent sample plots; the dead pine-lichen and moss pine-grass. The results showed that improvement thinning of moderate and severe intensity which are more profitable should be done in Scots pine forests of Kazakh Upland as well as carrying out such thinning increases the yield of the larger logs and increases the value of the left stand

Review of the fast growing forest tree species in Turkey

Los antecedentes de la utilización de especies de crecimiento rápido en Turquía tienen se remontan a 50 años y en los últimos 35-40 años se ha abrodado desde un punto de vista científico. Eucalyptus camaldulensis Dehn., E. grandis W.Hill., Pinus pinaster Ait., P. radiata D. Don., chopos híbridos, algunos clones de Populus deltoides Bartr. ex Marsh. y P. nigra L. son las especies más importantes por su mayor utilización en ensayos de especies, orígenes y en plantaciones. Aunque las especies y orígenes americanas son los más usados en los ensayos, los resultados esperados no han podido ser alcanzados debido al bajo número de clones y orígenes, establecidos en los experimentos que no representan el área de distribución natural. Junto con estas especies, los estudios deberían centrarse en Pinus brutia Ten. que tiene una amplia área de distribución natural en Turquía, elevado potencial y caracteres relacionados con el crecimiento rápido. Además, P. brutia esta considerado como una especie que podría cubrir el déficit de suministro a largo plazo. También, los estudios deberían ocuparse de Fraxinus angustifolia Wahl. subsp. oxycarpa Bieb ex Willd., Salix excelsa J. F. Gmelin., S. Alba L., Pterocarya fraxinifolia Spach. y Alnus glutinosa Gaertn. subsp. barbata (C. A. Mey.) Yalt que fueron probados en varias regiones y mostraron mejores características de crecimiento rápido que otras especies de aliso indígenas._____________________________________The fast growing species have 50 year-old political and 35-40 year-old scientific background in Turkey. Eucalyptus camaldulensis Dehn., E. grandis W.Hill., Pinus pinaster Ait., P. radiata D. Don., hybrid poplars, some clones of Populus deltoides Bartr. ex Marsh. and P. nigra L. are the most important species for obtaining a great deal of progress in species and origin experiments and starting the plantation phase in Turkey. In fast growing species process; although the American species and origins are mostly used, the desired outcomes could not be achived because of establishing the experiments with few number of clones and origins, which didn’t represent the natural distribution area. Along with these species, studies should be focused on Pinus brutia Ten. which has broad natural distribution area in Turkey, improvement potential and fast growing character. Furthermore, P. brutia is evaluated as a species which will close the supply deficit in long run. Also, studies should be performed on Fraxinus angustifolia Wahl. subsp. oxycarpa Bieb ex Willd., Salix excelsa J. F. Gmelin., S. alba L., Pterocarya fraxinifolia Spach. and Alnus glutinosa Gaertn. subsp. barbata (C. A. Mey.) Yalt. which was experimented in regional base and showed the faster growing character than the other indigenous alder species and native species

The Finslerian wormhole models

We present models of wormhole under the Finslerian structure of spacetime. This is a sequel of our previous work (Eur Phys J 75:564, 2015) where we constructed a toy model for compact stars based on the Finslerian spacetime geometry. In the present investigation, a wide variety of solutions are obtained that explore wormhole geometry by considering different choices for the form function and energy density. The solutions, like the previous work, are revealed to be physically interesting and viable models for the explanation of wormholes as far as the background theory and literature are concerned.Comment: 9 pages and 7 figue

Magnetic Field resulting from non-linear electrical transport in single crystals of charge-ordered Pr0.63_{0.63} Ca0.37_{0.37} MnO3_{3}}

In this letter we report that the current induced destabilization of the charge ordered (CO) state in a rare-earth manganite gives rise to regions with ferromagnetic correlation. We did this experiment by measurement of the I-V curves in single crystal of the CO system Pr$_{0.63}$Ca$_{0.37}$MnO$_{3}$ and simultanously measuring the magnetization of the current carrying conductor using a high T$_c$ SQUID working at T = 77K. We have found that the current induced destabilization of the CO state leads to a regime of negative differential resistance which leads to a small enhancement of the magnetization of the sample, indicating ferromagnetically aligned moments.Comment: 4 pages LateX, 4 eps figure

Non-linear electrical conduction and broadband noise in charge-ordered rare earth manganate Nd_0.5Ca_0.5MnO_3

Measurements of the dc transport properties and the low-frequency conductivity noise in films of charge ordered Nd_0.5Ca_0.5MnO_3 grown on Si subtrate reveal the existence of a threshold field in the charge ordered regime beyond which strong non linear conduction sets in along with a large broad band conductivity noise. Threshold-dependent conduction disappears as T -> T_{CO}, the charge ordering temperature. This observation suggests that the charge ordered state gets depinned at the onset of the non-linear conduction.Comment: 3 pages of two-column text and 4 eps figure

Experiences on Establishment of Scots Pine (Pinus sylvestris L.) Plantation in Ash Dump Sites of Reftinskaya Power Plant, Russia

Since the middle of the last century in the Urals of Russia there has been a problem of environmental pollution by man-made emissions. The purpose of this investigation has been to summarize the recultivation experience of Reftinskaya power plant ash dump. The station was put into operation in 1970 and it is the largest one in Russia. Specific feature of the used coal is high content of ash (47%). Daily consumption of coal in winter period constitutes 48 thousand tons. Yearly emissions of the station constitute 400 thousand tons. The main components of the emissions are sulphureous anhydride (up to 40%) solid stuff (up to 50%) and nitric oxides. The Scots pine (Pinus sylvestris L.) plantations on ash dumps have shown good adaptation and growth. The plantations have formed 143 m(3)/ha total volume at the age of 20 in 1st site index of the recultivation site of the ash dump with ash layer up to 7 m. Weakly alkaline reaction of the ash spread by wind promoted soil dioxidation that results in soil fertility increasing significantly on territory of adjacent stands. Recultivation process includes two main stages which are ash dump surface covering with 25-40 cm soil layer, planting with 2-year old Scots pine (Pinus sylvestris L.) seedling

Laws of Black Hole Mechanics from Holst Action

The formulation of Weak Isolated Horizons (WIH) based on the Isolated Horizon formulation of black hole horizons is reconsidered. The first part of the paper deals with the derivation of laws of mechanics of a WIH. While the zeroth law follows from the WIH boundary conditions, first law depends on the action chosen. We construct the covariant phase space for a spacetime having an WIH as inner boundary for the Holst action. This requires the introduction of new potential functions so that the symplectic structure is foliation independent. We show that a precise cancellation among various terms leads to the usual first law for WIH. Subsequently, we show from the same covariant phase space that for spherical horizons, the topological theory on the inner boundary is a U(1) Chern-Simons theory.Comment: References added, Minor Corrections 25 pages 1 fi

Recrystallization of epitaxial GaN under indentation

We report recrystallization of epitaxial (epi-) GaN(0001) film under indentation.Hardness value is measured close to 10 GPa, using a Berkovich indenter. Pop-in burst in the loading line indicates nucleation of dislocations setting in plastic motion of lattice atoms under stress field for the recrystallization process. Micro-Raman studies are used to identify the recrystallization process. Raman area mapping indicates the crystallized region. Phonon mode corresponding to E2(high) close to 570 cm-1 in the as-grown epi-GaN is redshifted to stress free value close to 567 cm-1 in the indented region. Evolution of A1(TO) and E1(TO) phonon modes are also reported to signify the recrystallization process.Comment: 10 pages, 3 figures