scholarly journals Femelschlag oder Plenterung – Ein Vergleich aus betriebswirtschaftlicher Sicht | Irregular Shelterwood System or Selection ('Plenter') System – a Comparison from an Economic Point of View

1999 ◽  
Vol 150 (2) ◽  
pp. 49-55 ◽  
Author(s):  
Conradin Mohr ◽  
Christian Schori
Keyword(s):  
Timber Harvesting ◽  
Point Of View ◽  
Silver Fir ◽  
Selection System ◽  
Operational Parameters ◽  
Economic Point ◽  
System A ◽  
Selection Forest ◽  
Harvesting Costs ◽  
Forest District

The state-owned forest enterprise of the former forest district of Berne introduced cost accounting per forest unit in 1981. The present study compares the irregular shelter-wood units with the selection ('plenter') system units on the basis of important operational parameters. Overall profits from timber production in the selection forest units exceeded those of the irregular shelterwood units by an average of 25 Swiss francs/m3. Selection system unit expenditure was lower by 15 Swiss francs/m3. The selection system has the advantage of incurring substantially lower planting and tending costs whereas timber harvesting costs for both parts of the forest enterprise were about the same. Up until 1991, the selection forests achieved higher yields with an average of 15.– Swiss francs/m3. Due to the decline of the silver fir price, however, there has been no difference in this parameter since 1992. Thus, apart from the advantages of the selection forest regarding ecology and the protection function, economic reasons also support this particular method of treatment.

scholarly journals Application of electrocoagulation for water conditioning

2019 ◽  
Vol 6 (2) ◽  
pp. 59-70
Author(s):  
Hana Posavčić ◽  
Ivan Halkijević ◽  
Živko Vuković
Keyword(s):  
Water Source ◽  
Point Of View ◽  
Pollutant Removal ◽  
Operating Costs ◽  
Mechanical Equipment ◽  
Operational Parameters ◽  
Economic Point ◽  
Water Conditioning ◽  
Electrocoagulation Process

Water conditioning is a method of removing altering minerals, chemicals and contaminants from a water source and it is carried out on facilities equipped with the corresponding electro-mechanical equipment. Although efficient, conventional processes typically use several complex devices connected to a single functional unit, which are often expensive to maintain and occupy large areas. Therefore, the aim of this paper is to present the electrocoagulation (EC) method as an alternative to conventional water conditioning processes. The examples of previous studies of the EC process application is presented in this paper. The focus of the paper is to investigate the influence of the certain operational parameters such as pH, temperature, electrode material, etc., on the efficiency of pollutant removal such as Escherichia coli and elevated concentrations of iron, arsenic, manganese, ammonia and others. Further, an economic analysis is made, which, from an economic point of view, shows when it is feasible to use the EC in the conditioning process. Furthermore, a case study of electrocoagulation process for Total Nitrogen (TN) removal is presented. According to results, 69.7 % of TN was removed with aluminum electrodes after 240 minutes. For this case, total operating costs were 7.60 €/m3.

scholarly journals Mathematical Modeling Framework of Physical Effects Induced by Sediments Handling Operations in Marine and Coastal Areas

2019 ◽  
Vol 7 (5) ◽  
pp. 149 ◽  
Author(s):  
Iolanda Lisi ◽  
Alessandra Feola ◽  
Antonello Bruschi ◽  
Andrea Pedroncini ◽  
Davide Pasquali ◽  
...  
Keyword(s):  
Coastal Areas ◽  
Point Of View ◽  
Sediment Source ◽  
Operational Parameters ◽  
Intervention Site ◽  
Modeling Framework ◽  
Economic Point ◽  
Fine Grained ◽  
Critical Issues ◽  
Definition Of

In recent years increasing attention has been paid to environmental effects that may result from marine dredging and disposal operations. In general, the fine-grained fraction of handled sediments can be dispersed far from the intervention site as a turbidity plume, depending on the specific site and operational parameters. Starting from a literature review, this paper suggests standards for estimating and characterizing the sediment source term, for setting up far-field modeling studies and analyzing numerical results, with the aim of optimizing, also from an economic point of view, the different project, execution and monitoring phases. The paper proposes an integrated modeling approach for simulating sediment dispersion due to sediment handling operations in different marine-coastal areas (off-shore, near-shore and semi-enclosed basins). Attention is paid to the characterization of sediment source terms due to different operational phases (removal, transport and disposal). The paper also deals with the definition of accuracy level of modeling activities, with regard to the main physical processes characterizing the different marine–coastal areas and to the type of environmental critical issues near the intervention site (if any). The main relationships between modeling and monitoring are given for the different design and management phases to support the selection of appropriate technical alternatives and monitoring actions and to ensure the environmental compliance of the proposed interventions.

scholarly journals Ertragskundliche Leistung in den Plenterwald-Versuchsflächen der Schweiz | Yield performance in the plenter forest research plots in Switzerland

2009 ◽  
Vol 160 (6) ◽  
pp. 162-174 ◽  
Author(s):  
Andreas Zingg ◽  
Fritz Frutig ◽  
Anton Bürgi ◽  
Renato Lemm ◽  
Vinzenz Erni ◽  
...  
Keyword(s):  
Growth Parameters ◽  
Basal Area ◽  
High Volume ◽  
Timber Harvesting ◽  
Growth And Yield ◽  
Silver Fir ◽  
Forest Research ◽  
Growing Stock ◽  
The Future ◽  
Harvesting Costs

22 plenter forest research plots, some of which are under long-term observation, allow the assessment of the performance of these stands and to a certain extent these performances can also be compared with the perfor mances of other management systems. The performance descriptions presented here are in a broad sense of the term growth and yield: the pure growth parameters for four selected areas are complemented by a modelling of the economic results by determination of the timber harvesting costs and the revenues. Young forest surveys were also made in four areas and thus allow us a glimpse into the future development. Most of the areas presented here lie in the silver fir - beech belt, some in the upper montane and in the subalpine zone and only one in a stand rich of broad-leaved trees. An equilibrium model can be calculated for most of these stands. The high altitude areas, two stands with high volume retention and conversion stands were exceptions. These areas showed high fluctuations in the growing stock. In contrast the increment remains the same over a large range of the growing stock. Utilization and increment are on the average in a similar magnitude. Standing volume and heavy timber proportions are lower in higher altitudes due to site conditions. The modelled revenues after deducting harvesting costs can be partly correlated with the diameter of the mean basal area tree of the harvested logs. Based on the stem number distribution from the one year old plant to the thickest tree, the sustainability of the forest effects – timber extraction or protection – for four areas is assured in the future. It can be shown with this data that the big advantage of selection forests lays in the regularity of these performances and this also on small areas.

Erfolgsfaktoren und Schwierigkeiten bei der Plenterung und Überführung im Privatwald | Factors of success and difficulties with selection and transition in the private forest

2009 ◽  
Vol 160 (1) ◽  
pp. 11-14
Author(s):  
Walter Linder ◽  
Walter Marti
Keyword(s):  
Success Factors ◽  
Organic Production ◽  
Point Of View ◽  
Basic Site ◽  
Specific Information ◽  
Private Forest ◽  
Economic Point ◽  
Natural Production ◽  
Forest Mountain ◽  
Selection Forest

Sylvicultural concepts regarding a permanent forest stand (permanent forest, selection forest, mountain selection forest) are becoming increasingly important. From an economic point of view these concepts are interesting since the organic production is extensive work with a high portion of growing quality wood. Motivated by the Binding Forest Award 2007, given to the community of Sumiswald and regarding the subject “success in the natural production forest”, the methods, success factors and the difficulties with the selection in the private forest of the Emmental are described. It shows that despite the frequent lack of basic site and stand specific information, a transition of the forest stands towards selection forests is possible if the forest owners, supported by experts and the local forest service, are consequently striving for this goal.

scholarly journals Bioactive Potential of Minor Italian Olive Genotypes from Apulia, Sardinia and Abruzzo

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1371
Author(s):  
Wilma Sabetta ◽  
Isabella Mascio ◽  
Giacomo Squeo ◽  
Susanna Gadaleta ◽  
Federica Flamminii ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Point Of View ◽  
Production Chain ◽  
Economic Point ◽  
System A ◽  
Stable Production ◽  
Italian Regions ◽  
Olive Cultivars ◽  
Local Genotypes ◽  
Bioactive Potential

This research focuses on the exploration, recovery and valorization of some minor Italian olive cultivars, about which little information is currently available. Autochthonous and unexplored germplasm has the potential to face unforeseen changes and thus to improve the sustainability of the whole olive system. A pattern of nine minor genotypes cultivated in three Italian regions has been molecularly fingerprinted with 12 nuclear microsatellites (SSRs), that were able to unequivocally identify all genotypes. Moreover, some of the principal phenolic compounds were determined and quantified in monovarietal oils and the expression levels of related genes were also investigated at different fruit developmental stages. Genotypes differed to the greatest extent in the content of oleacein (3,4-DHPEA-EDA) and total phenols. Thereby, minor local genotypes, characterized by stable production and resilience in a low-input agro-system, can provide a remarkable contribution to the improvement of the Italian olive production chain and can become very profitable from a socio-economic point of view.

High-resolution electron microscopy of Cu2O surfaces

1986 ◽  
Vol 44 ◽  
pp. 396-397
Author(s):  
V. Castano ◽  
W. Krakow
Keyword(s):  
High Resolution ◽  
Natural Extension ◽  
High Resolution Electron Microscopy ◽  
Point Of View ◽  
Initial Oxidation ◽  
System A ◽  
Resolution Electron ◽  
Surface Reconstructions ◽  
Atomic Surface ◽  
Au Thin Films

In non-UHV microscope environments atomic surface structure has been observed for flat-on for various orientations of Au thin films and edge-on for columns of atoms in small particles. The problem of oxidation of surfaces has only recently been reported from the point of view of high resolution microscopy revealing surface reconstructions for the Ag2O system. A natural extension of these initial oxidation studies is to explore other materials areas which are technologically more significant such as that of Cu2O, which will now be described.

Sophie Laws, with Caroline Harper and Rachel Marcus. Research for Development: A Practical Guide. New Delhi: Vistaar Publications. 2003. xiii+475 pages. Paperback. Indian Rupees 450.00.

2003 ◽  
Vol 42 (2) ◽  
pp. 170-172
Author(s):  
Mir Annice Mahmood
Keyword(s):  
Policy Research ◽  
Point Of View ◽  
Basic Question ◽  
New Delhi ◽  
Economic Point ◽  
Scarce Resources ◽  
Is Research ◽  
The Subject ◽  
Development Workers

To implement any successful policy, research about the subject-matter is essential. Lack of knowledge would result in failure and, from an economic point of view, it would lead to a waste of scarce resources. The book under review is essentially a manual which highlights the use of research for development. The book is divided into two parts. Part One informs the reader about concepts and some theory, and Part Two deals with the issue of undertaking research for development. Both parts have 11 chapters each. Chapter 1 asks the basic question: Is research important in development work? The answer is that it is. Research has many dimensions: from the basic asking of questions to the more sophisticated broad-based analysis of policy issues. The chapter, in short, stresses the usefulness of research which development workers ignore at their own peril.

Mit Initialfemeln zum Plenterwald (Essay) | The creation of selection forest using initial femel cut (essay)

2009 ◽  
Vol 160 (6) ◽  
pp. 137-143
Author(s):  
Rudi Kynast
Keyword(s):  
Mixed Forest ◽  
Point Of View ◽  
Age Group ◽  
Black Forest ◽  
Crown Height ◽  
Short Intervals ◽  
Total Growth ◽  
Cost Calculations ◽  
Selection Forest ◽  
Individual Trees

Although selection forests have clear advantages over age-group forests in view of their total growth performance, their net product and their stability, not to mention the sustainability of their beneficial effect, the proportion of this type of forest is insignificantly small in Germany and also in mixed forest in the mountains. It is therefore all the more surprising that scarcely any discernable efforts have been made to increase the proportion of selection forests. For a conversion, an alternative model for the treatment of the stands is adopted, whereby it is no longer the encouragement of the growth to maturity of individual trees in the stand which is aimed for, but rather the transformation of the whole stand to a selection forest using available stand elements and elements created by an early initiation of regeneration. Based on his experience in the forestry district of Kirchzarten in the Black Forest, Germany, the author describes the procedure for a successful conversion. This is to be started as soon as possible, that is to say when the crown height of the trees is about 18 metres and with corresponding usable dimensions, using small group shelter-wood cuts, a so-called initial femel cut. To get the conversion started it is advisable to remove whole groups of predominantly badly situated and overgrown trees. The stand will be additionally structured later through further interventions at short intervals. In the process, here and there really well situated trees will actually be left to stand solitar y, in other places w hol e self-cont aine d groups will b e created and else where valuabl e mixed s tand elements will be selected for permanent preservation, this in order to create a situation in which there are about 35 overstorey trees per hectare. On the basis of his own cost calculations, the author comes to the conclusion that the conversion is, from a financial point of view, superior compared with the age-group forest in that it brings higher proceeds more quickly and more often.

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