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The authors construct an intertemporal model of rent-maximizing behavior on the part of a timber harvester under potentially multidimensional risk as well as geographical heterogeneity. Subsequently, the authors use recursive methods (specifically, the method of stochastic dynamic programing) to characterize the optimal policy function – the rent-maximizing timber-harvesting profile. One noteworthy feature of their application to forestry in the province of British Columbia, Canada is the unique and detailed information the authors have organized in the form of a dynamic geographic information system to account for site-specific cost heterogeneity in harvesting and transportation, as well as uneven-aged stand dynamics in timber growth and yield across space and time in the presence of stochastic lumber prices. Their framework is a powerful tool with which to conduct policy analysis at scale.

The main purpose of this study is revival of vernacular architecture of Zegalli houses, which can be beneficial in several aspects of sustainable architecture, and therefore, its reuse in contemporary architecture can be strongly recommended. Zegalli houses, in northern Iran, are almost-entirely wooden vernacular houses, which beside to having several aspects of sustainable architecture, have shown good resistance against past earthquakes. Their relatively good seismic performance is mainly because of their specific timber foundation, which creates a kind of rocking/rolling isolation, as well as their light weight and diagonally braced stiff walls.

In this paper, first the architectural features of Zegalli houses, particularly energy efficiency, sustainability and eco-friendliness are described. Then, their structural system, focusing more on their foundation, is discussed. Finally, a simplified model of the house, developed in a powerful finite element analysis program, is introduced, and sample results of a series of time history analyses (THA), employing three-component accelerograms of three selected earthquakes, are presented.

Results of THA show that the rocking/rolling behavior of foundation timbers in various levels significantly reduces seismic response of the house, leading to its stability against earthquakes with peak ground acceleration up to 0.25 g.

Regarding the architectural and structural merits of Zegalli houses, they can be considered as sustainable vernacular architecture, and therefore, architects and civil and structural engineers are encouraged to reconsider the use of these houses, with some modifications, in future developments.

3D dynamics analysis of Shikilli foundations of Zegalli houses is done for the first time in this study.

The purpose of this paper is to identify and describe key economic and policy‐related issues with regard to terrestrial C sequestration and provide an overview of the economics of C sequestration on agricultural soils in the USA.

Recent economic literature on carbon sequestration was reviewed to gather insights on the role of agriculture in greenhouse gas emissions mitigation. Results from the most salient studies were presented in an attempt to highlight the general consensus on producer‐level responses to C sequestration incentives and the likely mechanisms used to facilitate C sequestration activities on agricultural soils.

The likely economic potential of agriculture to store soil C appears to be considerably less than the technical potential. Terrestrial C sequestration is a readily implementable option for mitigating greenhouse gas emissions and can provide mitigation comparable in cost to current abatement options in other industries. Despite considerable research to date, many aspects of terrestrial C sequestration in the USA are not well understood.

The paper provides a useful synopsis of the terms and issues associated with C sequestration, and serves as an informative reference on the economics of C sequestration that will be useful as the USA debates future greenhouse gas emissions mitigation policies.

The techniques available for the repair of historic masonry structures are extremely wide ranging. The advantages and disadvantages of each type of repair can be evaluated in terms of cost, time and quality as with modern projects. It is however, important to realise that when repairs to historic buildings are selected they must conform to building conservation philosophy, or an ethical and principle based evaluation. The purpose of this paper (part 2 of 2) is to establish what is meant by principles in this context and wherever possible apply practical examples to illustrate these concepts.

Evaluative literature review of the principles encapsulated within building conservation philosophy utilising them to stimulate discussion on practical repair interventions.

It has been shown that the principles of building conservation philosophy must be considered prior to making decisions relating to masonry repair. These repairs have varying degrees of defensibility, and will ultimately lead to good or bad conservation approaches. This paper briefly discusses the principles, highlighting some of the issues that may be initially confusing to the practitioner.

The evaluation of building conservation philosophy for masonry repair, and more specifically the “principles” have been little studied. The importance of this cannot however be over stated, as far from being an esoteric concept it affects every practical repair. This work brings together the study of the philosophical and practical, enabling practitioners to better understand the ramifications of building conservation philosophy for their projects. It must however be emphasised that as with any aspect of philosophy, there is not necessarily a right or wrong answer, only higher levels of defence for the selected repairs.

The purpose of this paper is to introduce a capital return rate function for growth processes, and apply it to financial sustainability considerations in growing multiannual plants.

A partition function of change rate of capitalization is introduced, as well as that of capitalization itself, and the expected value of capital return rate is produced as the ratio of the two functions.

Financial sustainability significantly differs from maximum-yield sustainability, and does not depend on any external interest rate.

It is proposed that financial considerations should not be based on any arbitrary external interest. Neither should the shape of any yield function be neglected. Constancy of capital return rate in time is not assumed.

Two forestry examples show that the capital return rate is sensitive to rotation time, and in particular to the level of initial investment. The proposed procedure can be applied in the absence of periodic boundary conditions in time.

The methodology has not been applied in this field previously.

The aim of this study is to depict the spatial pattern of the development level of China's state-owned forest farms, thereby providing theoretical reference and empirical evidence for the improvement of the corresponding development policies.

A development evaluation index system was established in this paper to comprehensively measure the development level of China's state-owned forest farms based on the Pressure-State-Response (PSR) model analysis framework and the actual situation of state-owned forest farms by using the entropy weight - technique for order preference by similarity to an ideal solution (entropy weight TOPSIS) evaluation method and exploratory spatial analysis method.

Studies show that the state-owned forest farms in China are generally not well developed. The pressure system that represents the input level displays an apparent restrictive effect on provinces whose comprehensive score <0.15. The response system, which represents development dynamism, has an apparent restrictive function on the provinces whose comprehensive score is 0.35. In terms of the specific spatial characteristics, the V-shape displayed by southwest–northwest and southeast–northwest has an inward trend of gradual reduction, with high-low agglomeration and low-low agglomeration correlation effects as well as apparent basin characteristics.

In this paper, the development level and spatial pattern of state-owned forest farms in China were accurately depicted, and the development path support and decision-making basis were provided for improving the overall development level of state-owned forest farms in China.

Management implications of net present value computation are investigated in comparison to computation of capital return rate, in the absence of periodic boundary conditions.

The initial state of experimental forest stands is measured in the field. Further development of the stands is investigated using a growth model.

The capital return rate strongly depends on cutting limit diameter, whereas net present value (NPV) is insensitive to it. The net present value also is indecisive whether or not frequent further thinnings should be implemented. In the absence of further harvesting, the net present value of growth declines rapidly, as does the capital return rate. With repeated diameter-limit cuttings, the net present value declines even if the capital return rate is retained. After a few decades, the NPV stabilizes even if the capital return rate declines. On stands previously thinned from below, greater NPV is gained without further thinnings, whereas capital return rate requires repeated diameter-limit cuttings.

It appears difficult to formulate management instructions on the basis of NPV computations because of the indecisiveness of the results.

Regardless of the degree of decisiveness, NPV-based management results in losses of capital return.

Net present value of further growth is computed in the absence of periodic boundary conditions, and the outcome is compared with the statistically expected value of capital return rate.

In fire condition, the time to failure of a timber connection is mainly reliant on the wood charring rate, the strength of the residual wood section, and the limiting temperature of the steel connectors involved in the connection. The purpose of this study is to experimentally investigate the effects of loaded bolt end distance, number of bolt rows, and the existence of perpendicular-to-wood grain reinforcement on the structural fire behavior of semi-rigid glued-laminated timber (glulam) beam-to-column connections that used steel bolts and concealed steel plate connectors.

In total, 16 beam-to-column connections, which were fabricated in wood-steel-wood bolted connection configurations, in eight large-scale sub-frame test assemblies were exposed to elevated temperatures that followed CAN/ULC-S101 standard time-temperature curve, while being subjected to monotonic loading. The beam-to-column connections of four of the eight test assemblies were reinforced perpendicular to the wood grain using self-tapping screws (STS). Fire tests were terminated upon achieving the failure criterion, which predominantly was dependent on the connection’s maximum allowed rotation.

Experimental results revealed that increasing the number of bolt rows from two to three, each of two bolts, increased the connection’s time to failure by a greater time increment than that achieved by increasing the bolt end distance from four- to five-times the bolt diameter. Also, the use of STS reinforcement increased the connection’s time to failure by greater time increments than those achieved by increasing the number of bolt rows or the bolt end distance.

The invaluable experimental data obtained from this study can be effectively used to provide insight and better understanding on how mass-timber glulam bolted connections can behave in fire condition. This can also help in further improving the existing design guidelines for mass-timber structures. Currently, beam-to-column wood connections are designed mainly as axially loaded connections with no guidelines available for determining the fire resistance of timber connections exerting any degree of moment-resisting capability.

Increased emphasis on environment, increased faith in private sector forests rather than government‐owned plantations, and improved techniques for tree growing have led to changes in reforestation policies, particularly in timber‐importing countries. Farm and community forestry has become more important, and often involves mixed broadleaved species and selective logging rather than clearfell. Private profitability is often low, but social returns may be considerably greater, warranting government support. While governments have experimented with a variety of instruments to encourage reforestation, policies have not necessarily addressed the main impediments. Measures to increase the share of resource rent gained by tree growers relative to other stakeholders in the timber production pipeline could accelerate plantings.

The fire resistance of timber structures is heavily dependent on the fire behaviour of the connections between its structural elements. The experimental study presented in this paper aimed to investigate the fire performance of glued-laminated timber beam connections reinforced perpendicular-to-wood grain with self-tapping screws (STS).

Two full-size fire experiments were conducted on glulam beam-end connections loaded in flexure bending. Two connection configurations, each utilizing four steel bolts arranged in two different patterns, were reinforced perpendicular to wood grain using STS. The bolt heads and nuts and the steel plate top and bottom edges were fire protected using wood plugs and strips, respectively. Each connection configuration was loaded to 100% of the ultimate design load of the weakest unreinforced configuration. The test assemblies were exposed to elevated temperatures that followed the CAN/ULC-S101 standard fire time–temperature curve.

The experimental results show that the influence of the STS was significant as it prevented the occurrence of wood splitting and row shear-out and as a result, increased the fire resistance time of the connections. The time to failure of both connection configurations exceeded the minimum fire resistance rating specified as 45 min for combustible construction in applicable building codes.

The experimental data show the effectiveness of a simple fire protection system (i.e. wood plugs and strips) along with the utilization of STS on the rotational behaviour, charring rate, fire resistance time and failure mode of the proposed hybrid mass timber beam-end connection configurations.