The Silvicultural Management System in temperate and boreal forests: A case history of the Hokkaido Tokyo University Forest

1994 ◽  
Vol 24 (6) ◽  
pp. 1176-1185 ◽  
Author(s):  
Sadamoto Watanabe ◽  
Satohiko Sasaki

Forest managers need new approaches for maintaining high stand volumes while keeping forests continuously productive and economically profitable. The Silvicultural Management System (SMS) accomplishes these objectives by increasing large-sized trees for periodic harvest, and continuously maintaining stand volumes at their highest possible levels. This system takes advantage of the diversity in growth, vigor, and longevity of dominant trees from a wide range of tree species found in natural forest ecosystems. Under the SMS developed at the Tokyo University Forest in Hokkaido, 13–17% of the stand volume is harvested at a cutting cycle of 8–10 years by removing the oldest mature trees. Residual stand volumes are maintained at about 70–80% of the levels found in natural old-growth stands. This removal of the oldest trees keeps the stands in a continuously healthy and productive state. The cutting level is planned to ensure a sufficient harvest to cover the construction costs of a necessary high-density forest road network that provides the great logging efficiency and limited maximum yarding distances. This form of selection cutting has proven to be highly productive, surpassing even the production realized under clear cutting. Well-managed cuttings under SMS improve the quality and quantity of the timber resource, with particular emphasis upon premium-quality hardwoods. Guidelines are given for individual tree selection cutting to produce premium-quality hardwoods, and based upon a high-density forest road network. The value of this high-quality timber makes such low-volume logging operations profitable. The SMS also maintains a favorable forest ecosystem for diverse wildlife and flora, and several endangered or threatened wildlife species that depend upon less dense mature forests occur in SMS forests. Managed forests with high-volume stocking also serve as an effective carbon dioxide sink.

1985 ◽  
Vol 33 (2) ◽  
pp. 175-179
Author(s):  
P.J.M. Wijngaard ◽  
M.P. Reinders

A new planning model was developed that does not specify parallel road networks as in existing models (e.g. Larsson's). The new model, based on the 'travelling salesman' algorithm, consists of 2 complementary models for flat and broken terrain which are reproduced in the synopsis together with Larsson's model. Software (written in FORTRAN 77) was developed for these models, incorporating a database management system (an existing commercial program) for program variables. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2016 ◽  
Vol 167 (5) ◽  
pp. 294-301
Author(s):  
Leo Bont

Optimal layout of a forest road network The road network is the backbone of forest management. When creating or redesigning a forest road network, one important question is how to shape the layout, this means to fix the spatial arrangement and the dimensioning standard of the roads. We consider two kinds of layout problems. First, new forest road network in an area without any such development yet, and second, redesign of existing road network for actual requirements. For each problem situation, we will present a method that allows to detect automatically the optimal road and harvesting layout. The method aims to identify a road network that concurrently minimizes the harvesting cost, the road network cost (construction and maintenance) and the hauling cost over the entire life cycle. Ecological issues can be considered as well. The method will be presented and discussed with the help of two case studies. The main benefit of the application of optimization tools consists in an objective-based planning, which allows to check and compare different scenarios and objectives within a short time. The responses coming from the case study regions were highly positive: practitioners suggest to make those methods a standard practice and to further develop the prototype to a user-friendly expert software.


Author(s):  
Francisco Arcas-Tunez ◽  
Fernando Terroso-Saenz

The development of Road Information Acquisition Systems (RIASs) based on the Mobile Crowdsensing (MCS) paradigm has been widely studied for the last years. In that sense, most of the existing MCS-based RIASs focus on urban road networks and assume a car-based scenario. However, there exist a scarcity of approaches that pay attention to rural and country road networks. In that sense, forest paths are used for a wide range of recreational and sport activities by many different people and they can be also affected by different problems or obstacles blocking them. As a result, this work introduces SAMARITAN, a framework for rural-road network monitoring based on MCS. SAMARITAN analyzes the spatio-temporal trajectories from cyclists extracted from the fitness application Strava so as to uncover potential obstacles in a target road network. The framework has been evaluated in a real-world network of forest paths in the city of Cieza (Spain) showing quite promising results.


Author(s):  
R. Fekete ◽  
Gy. Haszonits ◽  
D. Schmidt ◽  
H. Bak ◽  
O. Vincze ◽  
...  

AbstractThe spread of alien species with the expansion of road networks and increasing traffic is a well-known phenomenon globally. Besides their corridor effects, road maintenance practices, such as the use of de-icing salts during winter facilitate the spread of halophyte (salt tolerant) species along roads. A good example is Plantago coronopus, a mainly coastal halophyte which has started spreading inland from the Atlantic and Mediterranean coastal habitats, recently reaching even Central European countries (e.g. Hungary). Here we studied the spread of this halophyte and tried to identify factors explaining its successful dispersion along roads, while also comparing native and non-native roadside occurrences with regard to altitude of the localities, size of roadside populations and frequency of roadside occurrences. We completed a comprehensive literature review and collected more than 200 reports of occurrence from roadsides spanning a total of 38 years. During systematic sampling the frequency of the species along roads was significantly higher in the Mediterranean (native area), than along Hungarian (non-native area) roads, however the average number of individuals at the sampling localities were very similar, and no significant difference could be detected. Using a germination experiment, we demonstrate that although the species is able to germinate even at high salt concentrations, salt is not required for germination. Indeed salt significantly decreases germination probability of the seeds. The successful spread of the species could most likely be explained by its remarkably high seed production, or some special characteristics (e.g. seed dimorphism) and its ability to adapt to a wide range of environmental conditions. Considering the recent and rapid eastward spread of P. coronopus, occurrences in other countries where it has not been reported yet can be predicted in coming years.


2012 ◽  
Vol 488-489 ◽  
pp. 253-257 ◽  
Author(s):  
Josef Hadipramana ◽  
Abdul Aziz Abdul Samad ◽  
Zi Jun Zhao ◽  
Noridah Mohammad ◽  
W. Wirdawati

Foamed concrete is material that can be used in wide range of constructions and produced in high density. This investigation examined effect of chopped Polypropylene Fiber (PF) that mixed into admixture concerning strength of foamed concrete high density. Mechanical test were performed to measure effect of PF on improving compressive and splitting tensile strength. Result indicate that PF significantly improving compressive strength and behavior of PF where drawn into foamed concrete similarly with normal concrete. The fibrillated PF has been occurred and reduced the micro crack of matrix and prevented propagation crack growth. The presence of PF improved splitting tensile strength was not significantly. Influence of porous of foamed concrete is considered. Scanning Electron Microscope (SEM) exhibits condition microstructure of foamed concrete reinforced PF that alter microstructure, especially interfacial bonding due to PF presence.


2021 ◽  
Vol 17 ◽  
pp. 100232
Author(s):  
Federico Cuppi ◽  
Valeria Vignali ◽  
Claudio Lantieri ◽  
Luca Rapagnà ◽  
Nicola Dimola ◽  
...  

Author(s):  
Huijun Chen ◽  
Jing Gao ◽  
Qian Xu ◽  
Dongmei Wan ◽  
Wenji Zhai ◽  
...  

The present study aims to explore the role of microRNA 145-5p (miR-145-5p) in hyperlipidemia. Using bioinformatics tools and a wide range of function and mechanism assays, we attempted to understand the specific function and potential mechanism of miR-145-5p in hyperlipidemia. A cholesterol-enriched diet induced an increase of serum cholesterol and triacylglycerol but a decrease of serum high-density lipoprotein. MiR-145-5p level was decreased in hyperlipidemia rat models. MiR-145-5p regulated lipid metabolism by antagonizing the alteration of high-density lipoprotein, cholesterol, and triacylglycerol in serum mediated by a cholesterol-enriched diet. In mechanism, miR-145-5p directly bound with p21 protein (RAC1)-activated kinase 7 (PAK7) and negatively regulated mRNA and protein levels of PAK7 in THP-1 cells. Furthermore, miR-145-5p level was negatively associated with PAK7 level in rat cardiac tissues. Finally, overexpression of PAK7 reversed the effects of miR-145-5p on β-catenin activation and M2 macrophages polarization in THP-1 cells. In conclusion, MiR-145-5p modulated lipid metabolism and M2 macrophage polarization by targeting PAK7 and regulating β-catenin signaling in hyperlipidemia, which may provide a potential biomarker for the treatment of hyperlipidemia-induced cardiovascular diseases.


Author(s):  
Alberto Mendoza ◽  
Aristóteles Uribe ◽  
Claudia Z. Gil ◽  
Emilio Mayoral

Two years ago, the Mexican Transportation Institute began to develop a computer-based management system of the information collected by various organizations about accidents occurring on the Federal Road Network. This system combines the information gathered by these organizations with the purpose of completing and validating the data so that tools can be developed for processing and analyzing the validated data and the processed data and developed tools can be made available to users. It was decided to support the development of such efforts on computer databases already being generated, on database processing and management software, on geographic information systems, and on remote data-exchange systems (e.g., the Internet). The progress made so far in the development of the computer system is reviewed. The system has been named the “Relational Accident Database Management System for Mexican Federal Roads” (SAIACF, in Spanish). The information sources beneficial to this project are identified and analyzed. The ideal scheme conceived for the integration of the various information sources is presented, and the SAIACF system is outlined. Some of the results obtained after its application to the information corresponding to 1997 are shown. Also, the element that was generated to make the information and the tools available to users is described, and conclusions are drawn.


2018 ◽  
Vol 196 ◽  
pp. 04063
Author(s):  
Jan Mikolaj ◽  
L’uboš Remek

Main goal of Road Network Management System is to ensure safety and continuity of road traffic on road network with low intensity and lower technical requirements. This is achieved with pavement management system (main component of road network management system). Most countries developed custom Pavement management systems (PMS) based on deterministic or probabilistic approach. Local road administrators of low level road networks often lack the software equipment such as HDM-4, RoSy, Exor, etc. These and similar PMS Most PMS, however effective, are often cumbersome, demanding in regard to energy, know-how and software equipment. The majority of local road administrators of rural road networks thus resort to non-effective reactive maintenance strategies. This article describes an easy to use method, based on predetermined maintenance repair & rehabilitation standards. Secondly, a simple method, based on road user cost, is introduced that administrator can use to prepare a list of road section eligible for repair according to their repair priority.


Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2569 ◽  
Author(s):  
Christos Keramydas ◽  
Georgios Papadopoulos ◽  
Leonidas Ntziachristos ◽  
Ting-Shek Lo ◽  
Kwok-Lam Ng ◽  
...  

This study investigates pollutant emissions and fuel consumption of six Euro VI hybrid-diesel public transport buses operating on different scheduled routes in a metropolitan urban road network. Portable emission measurement systems (PEMS) are used in measurements and results are compared to those obtained from a paired number of Euro V conventional buses of the same body type used as control over the same routes. The selected routes vary from urban to highway driving and the experimentation was conducted over the first half of 2015. The available emissions data correspond to a wide range of driving, operating, and ambient conditions. Fuel consumption, distance- and energy-based emission levels are derived and presented in a comparative manner. The effect of different factors, including speed, ambient temperature, and road grade on fuel consumption and emissions performance is investigated. Mean fuel consumption of hybrid buses was found 6.1% lower than conventional ones, from 20% lower up to 16% higher, over six routes tested in total. The mean route difference between the two technologies was not statistically significant. Air conditioning decreased consumption benefits of the hybrid buses. Decrease of the mean route speed from 15 km h−1 tο 8 km h−1 increased the hybrid buses consumption by 63%. Nitrogen oxides (NOx) emissions of the Euro VI hybrid buses were 93 ± 5% lower than conventional Euro V ones. Nitrous oxide (N2O) emissions from hybrid Euro VI buses made up 5.9% of total greenhouse gas emissions and largely offset carbon dioxide (CO2) benefits. The results suggest that hybrid urban buses need to be assessed under realistic operation and environmental conditions to assess their true environmental and fuel consumption benefits.


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