scholarly journals Biometric Parameters of Planting Material as a Test Indicator of Success of Pinus silvestris L. Plantations

Author(s):  
Natalia Sungurova ◽  
◽  
Anna Drochkova ◽  

The creation and cultivation of artificial plantations of conifers largely depends on the planting material quality. The paper is devoted to the study of the relationship between the main parameters of planting material of Scots pine (Pinus silvestris L.) with inventory indices of artificial plantations. Forest trials of Scots pine in the Arkhangelsk region, created in a haircap-moss forest site type, were investigated. Seedlings of Scots pine with standard size were divided into large, medium, small according to the diameter of the root cervix in order to set the experiment, which aimed to determine the relationship between the parameters of planting material and characteristics of the forming plantations. The research purpose determined the main task, mainly, to find out from which plants the “trees of the future” (fast-growing large specimens) are laid out. Plants grown from the large seedlings are characterized by the greatest height. This position, in relation to individuals formed from medium and small planting material, is maintained and gradually increases. From the initial phases of development, a kind of mobile equilibrium is established in the studied plantation. All the trees are growing at a very fast rate, but the initial (at the time of planting on the silvicultural area) size of the planting material corresponding to the pine plants that survived in different years on the plantations continues to remain constant. It was found that, the largest number of leaders (47 % of all survived seedlings) grew of the large seedlings by the end of the 2nd age class. Therefore, high-quality soil treatment together with the use of high-quality proportionally developed planting material significantly increases the inventory indices of plants in the stand, and allows getting the target assortments15–20 years earlier.

2019 ◽  
Vol 63 (3) ◽  
pp. 115-128 ◽  
Author(s):  
Maie Stein ◽  
Sylvie Vincent-Höper ◽  
Nicole Deci ◽  
Sabine Gregersen ◽  
Albert Nienhaus

Abstract. To advance knowledge of the mechanisms underlying the relationship between leadership and employees’ well-being, this study examines leaders’ effects on their employees’ compensatory coping efforts. Using an extension of the job demands–resources model, we propose that high-quality leader–member exchange (LMX) allows employees to cope with high job demands without increasing their effort expenditure through the extension of working hours. Data analyses ( N = 356) revealed that LMX buffers the effect of quantitative demands on the extension of working hours such that the indirect effect of quantitative demands on emotional exhaustion is only significant at low and average levels of LMX. This study indicates that integrating leadership with employees’ coping efforts into a unifying model contributes to understanding how leadership is related to employees’ well-being. The notion that leaders can affect their employees’ use of compensatory coping efforts that detract from well-being offers promising approaches to the promotion of workplace health.


2021 ◽  
Author(s):  
Robbie I’Anson Price ◽  
Francisca Segers ◽  
Amelia Berger ◽  
Fabio S Nascimento ◽  
Christoph Grüter

Abstract Social information is widely used in the animal kingdom and can be highly adaptive. In social insects, foragers can use social information to find food, avoid danger or choose a new nest site. Copying others allows individuals to obtain information without having to sample the environment. When foragers communicate information they will often only advertise high quality food sources, thereby filtering out less adaptive information. Stingless bees, a large pantropical group of highly eusocial bees, face intense inter- and intra-specific competition for limited resources, yet display disparate foraging strategies. Within the same environment there are species that communicate the location of food resources to nest-mates and species that do not. Our current understanding of why some species communicate foraging sites while others do not is limited. Studying freely foraging colonies of several co-existing stingless bee species in Brazil, we investigated if recruitment to specific food locations is linked to (1) the sugar content of forage, (2) the duration of foraging trips and (3) the variation in activity of a colony from one day to another and the variation in activity in a species over a day. We found that, contrary to our expectations, species with recruitment communication did not return with higher quality forage than species that do not recruit nestmates. Furthermore, foragers from recruiting species did not have shorter foraging trip durations than those from weakly-recruiting species. Given the intense inter- and intraspecific competition for resources in these environments, it may be that recruiting species favour food resources that can be monopolised by the colony rather than food sources that offer high-quality rewards.


2011 ◽  
Vol 243-249 ◽  
pp. 4956-4959
Author(s):  
Jian Chao Hao ◽  
Hui Fen Liu ◽  
Dong Ling Wei ◽  
Li Jun Shi ◽  
Jun Li Li ◽  
...  

The relationship between formaldehyde emission and time was researched and a mathematical model was developed which describes the variation of formaldehyde with time in the airtight chamber. It was found that high quality composite floor was in line with 0-order kinetic equation and low quality composite floor was in line with 1-order kinetic equation. Besides, the effect of activated carbon adsorption on formaldehyde was studied and the result showed that activated carbon had poor adsorption on formaldehyde for weak van der waals force.


2005 ◽  
Vol 94 (2) ◽  
pp. 244-255 ◽  
Author(s):  
Quan Wang ◽  
Samuel Adiku ◽  
John Tenhunen ◽  
André Granier

BioResources ◽  
2016 ◽  
Vol 11 (4) ◽  
Author(s):  
Ümit Büyüksarı ◽  
Nusret As ◽  
Türker Dündar ◽  
Ezel Sayan

2015 ◽  
Vol 12 (1) ◽  
pp. 177-191 ◽  
Author(s):  
C. Wu ◽  
I. Pullinen ◽  
S. Andres ◽  
G. Carriero ◽  
S. Fares ◽  
...  

Abstract. Impacts of soil moisture on de novo monoterpene (MT) emissions from Holm oak, European beech, Scots pine, and Norway spruce were studied in laboratory experiments. The volumetric water content of the soil, Θ, was used as the reference quantity to parameterize the dependency of MT emissions on soil moisture and to characterize the severity of the drought. When Θ dropped from 0.4 m3 × m−3 to ~0.2 m3 × m−3 slight increases of de novo MT emissions were observed but with further progressing drought the emissions decreased to almost zero. In most cases the increases of MT emissions observed under conditions of mild drought were explainable by increases of leaf temperature due to lowered transpirational cooling. When Θ fell below certain thresholds, MT emissions decreased simultaneously with Θ and the relationship between Θ and MT emissions was approximately linear. The thresholds of Θ (0.044–0.19 m3 × m−3) were determined, as well as other parameters required to describe the soil moisture dependence of de novo MT emissions for application in the Model of Emissions of Gases and Aerosols from Nature, MEGAN. A factorial approach was found appropriate to describe the impacts of Θ, temperature, and light. Temperature and Θ influenced the emissions largely independently from each other, and, in a similar manner, light intensity and Θ acted independently on de novo MT emissions. The use of Θ as the reference quantity in a factorial approach was tenable in predicting constitutive de novo MT emissions when Θ changed on a time scale of days. Empirical parameterization with Θ as a reference was only unsuccessful when soil moisture changed rapidly


2015 ◽  
Vol 3 (2) ◽  
pp. 121
Author(s):  
Ying-Leh Ling ◽  
Fairuz Ismail ◽  
Abdul Ghani Kanesan Abdullah

This study aims to examine the relationship between feedback environment practices and creativity in the educational organizations. This study is a quantitative study. A total of 40 polytechnic students from Polytechnic Kuching Sarawak are randomly selected to participate in this study. Data were obtained using a set of questionnaire consisting of three parts. The data obtained were analyzed descriptively and inferentially. Inferential analysis involves <em>t</em> test and Pearson correlation. The findings have shown that the level of feedback environment based on students' perception is high. Simultaneously, the level of creativity among the students is also high. The findings indicated that there is no significant difference in feedback environment between genders. Furthermore, the study also showed a significant and positive relationship between feedback environment and students’ creativity. The results of this study have several implications directly to the formation of high-quality students as feedback environment and students’ creativity are interrelated and inseparable in educational organizations.


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