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Open j.urnal of Forestry 2012年第3期2卷 138-149页

作者： Oliver Chikumbo thomas j. straka Department of Forestry and Natural Resources Clemson University Clemson USA Scion Rotorua New Zealand

A competitive co-evolutionary Multi-Obj.ctive Genetic Algorithm (cc-MOGA) was used to approximate a Pareto front of efficient silvicultural regimes for Eucalyptus fastigata. The three obj.ctives to be maximised included, sawlog, pulpwood and carbon sequestration payment. Three carbon price scenarios (3CPS), i.e. NZ $25, NZ $50 and NZ $100 for a tonne of CO2 sequestered, were used to assess the impact on silvicultural regimes, against a fourth non-carbon Pareto set of efficient regimes (nonCPS), determined from a cc-MOGA with two obj.ctives, i.e. competing sawlog and pulpwood productions. Carbon prices included in stand valuation were found to influence the silvicultural regimes by increasing the rotation length and lowering the final crop number before clearfell. However, there were no significant changes in the frequency, timing, and intensity of thinning operations amongst all the four Pareto sets of solutions. However, the 3CPS were not significantly different from each other, which meant that these silvicultural regimes were insensitive to the price of carbon. This was because maximising carbon sequestration was directly related to the biological growth rate. As such an optimal mix of frequency, intensity, and timing of thinning maintained maximum growth rate for as long as possible for any one rotation.

关键词： Optimal Control Competitive Co-Evolutionary Multi-Obj.ctive Genetic Algorithm (cc-MOGA) Pareto Front Forest Holding Value Kruskal-Wallis Test Multiple Comparison Procedure

Forestland and Timber Donations: Challenging Management Opportunities for Foundations

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Open j.urnal of Forestry 2012年第4期2卷 257-264页

作者： Phillip Lee Ward thomas j. straka School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

Over half of the forestland in the United States is in private hands. j.st over 10 million individual and family owners control about 60% of this private forestland. Ownership of family forests changes on a regular basis;sometimes from generation to generation and sometimes to outside of the family. Often new owners are not interested in forest management and sell off the asset. Some owners attempt to ensure their family forest remains pristine and undeveloped. This is leading to timberland donations to entities that can be expected to hold the donated forest permanently and ensure sustainable forest management. University foundations and forestry schools are increasingly receiving timberland as donations. It is a way for donors to monetize the asset (with tax breaks) and protect it at the same time. Foundations have a problem with timberland as they often don’t fully understand it as an investment. Certainly there are even times when a foundation should not accept it as a donation. The nature of timberland as an investment is explained, along with basic terminology that is common use. Age class distribution and the resulting cash flow dis- tribution is explained, as well as timber volume, harvest scheduling, timberland investment analysis, tim- ber value, timber sales, and timber contracts. All of these are tools foundation board members need to evaluate timberland donations.

关键词： Foundation University Foundation Donation Timberland Donation Forestry Investment

Urban Forest and Tree Valuation Using Discounted Cash Flow Analysis: Impact of Economic Components

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Open j.urnal of Forestry 2012年第3期2卷 174-181页

作者： Kristin S. Peterson thomas j. straka School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

Discounted cash flow analysis is one of the standard methods used to value urban forests and trees. It involves calculating today’s value for all benefits and costs attributed to an investment;that is discounting all cash flows to today’s value using an appropriate interest rate. This requires each benefit and cost be stated in terms of its cash flow. Urban tree benefits are complex. Little notice is given to the components of these benefits. Total urban tree benefits are a summation of partial benefits, including property value increase, storm water reduction, air quality improvement, carbon sequestration, natural gas savings, and electricity savings. We discuss the nature of these partial benefits, especially the geographical, temporal, diameter size, and rate of growth differences. These differences are even reflected in nursery stock valuation. Net present value analysis is used to illustrate the impact of these differences on financial return. An understanding of these components will prove valuable to those attempting to estimate urban forest and tree benefits.

关键词： Urban Forest Benefits Costs Economic Components Discounted Cash Flow Analysis Arboriculture

Evaluating Structural and Temporal Factors Affecting Supply of Ecosystem Benefits in a University Urban Environment in South Carolina, USA

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Open j.urnal of Forestry 2022年第3期12卷 297-311页

作者： Puskar N. Khanal Raj.n Paraj.li thomas j. straka Department of Forestry & Environmental Conservation Clemson University Clemson SC USA Department of Forestry & Environmental Resources North Carolina State University Raleigh NC USA

Sustainable urban forest management is still an evolving concept, particularly as it pertains to a sustainable supply of ecosystem benefits and management planning. Urban forestry maintains a greater human dimension component than traditional timber-oriented rural forestry because urban trees grow in city centers and neighborhoods, supplying critical ecosystem benefits to the population centers. The overall goal of this study was to evaluate the relationship of urban forest stand structure and its temporal dynamics with the sustainable supply of ecosystem benefits in university environments. Individual tree data were collected from a completed inventory, while the i-Tree Eco model was used to generate ecosystem benefits data from the Clemson urban forest. The cumulative-benefits supply curve had an inverted j.shaped curve, but the average supply curve had a negative slope against the species richness. Likewise, individual tree variables total height, DBH, leaf area, and crown height strongly correlated with the total ecosystem services supply. Based on the temporal supply trends, the study area trees were broadly segmented into three groups: establishment, growth, and legacy, with 65%, 31%, and 4% frequency distribution, respectively. Urban forest managers need to identify forest management goals and preferred ecosystem benefits among the urban communities to guide the required forest structure and dynamics to ensure a sustainable and functioning urban forest.

关键词： Sustainability Urban Forest Structure Ecosystem Services i-Tree Economic Benefits

The Economic Contribution of Natural Resources to a State Economy: A South Carolina Case Study

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Natural Resources 2017年第3期8卷 115-129页

作者： David B. Willis thomas j. straka College of Agriculture Forestry and Life Sciences Clemson University Clemson SC USA

The structure of state or sub-state regional economies is heavily influenced by its natural resource endowment. Input-output analysis is often used to estimate the economic contribution of various sectors to a state’s economy. We apply input-output analysis to South Carolina’s economy to estimate the contribution of natural resource-based sectors to the overall economy. The natural resource-based sectors consist of six mutually exclusive sectors: fishing, hunting, and wildlife viewing;coastal tourism;commercial fisheries;boat industry;mining;and forestry. The total economic contribution of these six natural resource-based sectors is $33.4 billion, representing 8.3% of gross state product and 8.6% of all state employment.

关键词： Natural Resources South Carolina Input-Output Analysis Economic Contribution

Family Forest Owners’ Motivation to Control Understory Vegetation: Implications for Consulting Forestry

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Open j.urnal of Forestry 2013年第4期3卷 99-103页

作者： Alex C. Londeau thomas j. straka School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

Forest vegetation management has evolved as a recognized component of intensive forest management practice. It involves the management of competing vegetation necessary to obtain the high yields expected in modern forest plantations via control of interfering plants that influence regeneration outcome, impact timber stand development, and limit native plant and wildlife diversity. It includes cultural control, fire control, mechanical control, biological control, and chemical control. The public perception of forest vegetation management, especially chemical control, is sometimes negative due to health and environmental concerns. It is an important tool in the forest management alternatives available to consulting foresters managing family forest lands (the vast maj.rity of private forest land in the United States). We report on a study that addresses the motivations of family forest owners that implement forest vegetation management practices and the motivation of those who chose not to implement after forester recommendations to do so. For those who do implement forest vegetation management, improvement of wildlife habitat and increased timber growth was the main motivation. For those who did not, cost was the main concern. Size of forest holding plays a maj.r role in determining who will practice intensive forestry.

关键词： Forest Vegetation Management Chemical Control Family Forest Owners Consulting Forestry

Incremental Investment Value of Wild Turkey Management on the South Carolina Piedmont

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Natural Resources 2014年第12期5卷 719-731页

作者： j.seph D. Hammond thomas j. straka Tyler A. Brown Divison of Natural Resources Clemson University Clemson SC USA National Wild Turkey Federation Edgefield SC USA

Optimal timber production and healthy wild turkey populations can be j.intly achieved by balancing cutting cycles, habitat types, and food sources. Expected financial returns from wild turkey management and the habitat required to maintain those returns are estimated. A geographical information system (GIS) is used to illustrate the methodology necessary to distinguish various levels of potential quality turkey habitat, including broad forest conditions across ownerships, like early successional habitat, pine hardwood mixtures, and forest openings, that intermix and combine to form superior wild turkey habitat. A financial analysis framework that considers key financial variables is applied across management regimes to determine net present values, land expectation values, and equivalent annual incomes. Incremental hunting lease revenue from wild turkey hunting leases is shown to impact investment return. The financial framework allows managers to perform sensitivity analyses of costs and revenues to better evaluate management alternatives.

关键词： Wild Turkey Habitat Management Financial Analysis GIS Analysis

The Enduring Fundamental Framework of Forest Resource Management Planning

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Natural Resources 2013年第6期4卷 423-434页

作者： Robert D. Tew thomas j. straka Tamara L. Cushing School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

Forest resource management planning began in the United States at the turn of the nineteenth century with an emphasis on timber production, sustained yield, and maximum timber growth. A set of well-documented procedures, philosophies, rules, and understandings developed within the forestry profession on the reasons for and requirements of a professionallydeveloped forest resource management plan. For most of the next decade, this framework controlled the development of timber-oriented forest management plans. In the late twentieth century, the forest resource management plans became stewardship- or sustainability-oriented. A broader expansive framework that stressed sustainable forest management developed. However, the framework of both types of plans is fundamentally the same. The natural resource being manipulated is still timber and that is the variable the management plan still focuses on. The set of fundamental underpinnings to the forest management plan has not changed. We describe these underpinnings in terms of both types of forest management plan, as they have remained unchanged over time. Also addressed are the questions of who are the forest owners that plan and what are the differences in the type of forest management plans they prepare.

关键词： Forest Resource Management Plan Forest Resource Management Planning Sustainable Forest Management

Consanguine Philosophies of Traditional Timber-Based and Contemporary Sustainability-Based Forest Resource Management Plans

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Natural Resources 2013年第5期4卷 387-394页

作者： thomas j. straka Robert D. Tew Tamara L. Cushing School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

The earliest American forest resource management plans date to the birth of the forestry profession around 1900. For the next half century, these management plans were essentially timber production management plans. Certainly, other forest values, especially watershed protection, were important parts of the planning. But not until the second half of the twentieth century did multiple-use and a wide array of forest values become normal components of a forest management plan. Within the last twenty-five years forest management plans have developed a forest stewardship or sustainable forest management foundation. That is, a forest resource management plan is now expected to consider an entire set of forest values, to have a long-term sustainability focus, and to meet a set of expected management and operational criteria. Often, the forest management plan is the basis of a forest certification scheme. The early forest management plans were primarily timber-based and thus had a commercial or financial focus. Today’s forest management plans are based on multiple forest values and may or may not have a financial focus. We contrast the traditional timber management plan with today’s sustainable forest management plan, realizing the basis of both plans is by definition the forest or the timber. Involving both timber harvesting activities and the operational foundation of the sustainable forest management plan is essentially a timber management plan. One cannot ignore the fact that all forest management plans accomplish silvicultural obj.ctives via manipulation of timber density variables, like stocking and spacing. Management of a forest still involves timber harvests. Our discussion shows that the timber management plan is still very much alive and forms the basis of modern sustainable forest management plans.

关键词： Forest Management Plan Forest Management Planning Forest Sustainability Sustainable Forest Management

Sustainability and Forest Certification as a Framework for a Capstone Forest Resource Management Plans Course

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Open j.urnal of Forestry 2012年第3期2卷 159-166页

作者： Christine M. Watts Lauren S. Pile thomas j. straka School of Agricultural Forest and Environmental Sciences Clemson University Clemson USA

Forest sustainability is the foundation of forestry and modern forest management. Originally the central concept was sustained-yield and maximum timber production and then multiple-use and other non-timber values gained importance. After the Rio Conference and development of the Montréal Process in the early 1990’s, forest sustainability rapidly gained importance and various forest certification schemes developed to certify forest products that were grown using sustainable forest management. Forest sustainability and forest certification have become critical topics in forestry curricula. The American Tree Farm System is one of the important North American forest certification organizations. Modern forestry curricula often include a capstone course where forest management plans are developed. We describe a capstone course at Clemson University under development that uses the management standards and management plan template of the American Tree Farm System as a framework for students to develop actual forest management plans for local forest owners. The material is integrated into a series of four courses leading up to the capstone course. The course offered a hands-on approach for students to create management plans using actual certification standards and the system’s management plan template. In addition, students received specialized training to qualify as auditors for the certification system. This is an example of forest sustainability being integrated into the forestry curriculum.

关键词： Forest Certification Forest Sustainability American Tree Farm System (ATFS) Forestry Education