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  • 1.
    Abedi, Tooba
    et al.
    Univ Guilan, Rasht, Iran.
    Mohammadi Limaei, Soleiman
    Univ Guilan, Rasht, Iran; Univ Guilan, Sowmeh Sara, Iran.
    Bonyad, Amir Eslam
    Univ Guilan, Rasht, Iran; Univ Guilan, Sowmeh Sara, Iran.
    Torkaman, Javad
    Univ Guilan, Sowmeh Sara, Iran.
    Optimal rotation age of Populus deltoides considering economic value of timber harvesting and carbon sequestration2018Ingår i: Austrian Journal of Forest Science, ISSN 0379-5292, E-ISSN 1815-3704, Vol. 135, nr 4, s. 315-342Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research is to determine the optimal rotation age of Populus deltoides plantations regarding to the timber and carbon sequestration values in the north of Iran. Two plantation types with a tree density of 3 by 3 m and of 3 by 4 m were considered in Choobar forest, northern Iran. Net present value (NPV) of timber and carbon were used for determining the optimal rotation age. Data on volume increment, carbon content, revenue, timber and carbon prices were collected to estimate NPV. In this study, we considered the effects of different plantation cost, land value and discount rates on the optimal rotation ages. Our results indicated, if economic value of timber is considered, optimal rotation ages were 10 and 8 years for 3 by 3 m and 3 by 4 m density, respectively. Optimal rotation ages considering carbon sequestration, in addition to timber value, increased to 14 and 11 years for the same two densities, respectively. Thus, integrating carbon sequestration value with timber economic value increased the optimal rotation ages and in turn change the optimal forest management. Sensitivity analysis indicate that optimal rotation ages increased with increasing plantation cost and decreased with increasing interest rate, while our results suggested that the optimal rotation age is not sensitive to the land value. Our results are important for land managers and carbon projects to optimize the used forest management practices.

  • 2.
    Etemad, Seyedeh Soma
    et al.
    Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för ekonomi, geografi, juridik och turism. Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Yousefpour, Rasoul
    Department of Forestry Economics and Forest Planning, University of Freiburg, Freiburg, Germany.
    Forest management decision-making using goal programming and fuzzy analytic hierarchy process approaches (case study: Hyrcanian forests of Iran): Forest management decision-making2019Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 65, nr 9, s. 368-379Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study is to determine the optimum stock level in the forest. In this research, a goal programming method was used to estimate the optimal stock level of different tree species considering environmental, economic and social issues. We consider multiple objectives in the process of decision-making to maximize carbon sequestration, net present value and labour. We used regression analysis to make a forest growth model and allometric functions for the quantification of carbon budget. Expected mean price is estimated using wood price and variable harvesting costs to determine the net present value of forest harvesting. The fuzzy analytic hierarchy process is applied to determine the weights of goals using questionnaires filled in by experts in order to generate the optimal stock level. According to the results of integrated goal programming approach and fuzzy analytic hierarchy processes, optimal volume for each species was calculated. The findings indicate that environmental, economic and social outcomes can be achieved in a multi-objective forestry program for the future forest management plans.

  • 3.
    Etembad, Soma
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Yousefpour, Rasoul
    University of Freiburg, Freiburg, Germany.
    Decision making on Sustainable Forest Harvest Production Using Goal Programming Approach: Case study: Iranian Hyrcanian Forest2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper aims to determine the optimal stock level in Hyrcanian forest of Iran. In this study, a goal programming techniques used to estimate the optimum stock level of different tree species considering economics, environmental and social issues. We consider multiple objectives in the process of decision making to realize the balance of maximizing annual growth, net present value, carbon sequestration and labor. We use regression analysis to develop a forest growth model using allometric functions for the quantification of carbon budget. The expected mean price was estimated to determine the net present value of forest harvesting. We use Expert knowledge to weight the goals in order to generate the optimal stock level. Results show that the total optimum stock is 0.5% lower than based on questioners. The results indicate that goal programming is a suitable methodology in this case. 

  • 4.
    Fu, Qiang
    et al.
    Department of Geography, 1255 Bunche Hall Box 951524, Los Angeles, CA 90095, USA.
    Saatchi, Sassan S.
    2 NASA Jet Propulsion Laboratory, 4800 Oak Grove Blvd, Pasadena, CA 91109, USA.
    Nouri, Ali
    Institute of Environment, La Kretz Hall, Suite 300, Los Angeles, CA 90095-1496, USA.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Land use and land cover classification and change detection of the Caspian Sea forest belt2010Konferensbidrag (Refereegranskat)
  • 5.
    Hatami, Nishtman
    et al.
    Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
    Lohmander, Peter
    Optimal Solutions in Cooperation with Linnaeus University, Växjö.
    Moayeri, Mohammad Hadi
    Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    A basal area increment model for individual trees in mixed continuous cover forests in Iranian Caspian forests2018Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, s. 1-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran. We analyzed 421 core samples from 6 main species in the forest area to develop our growth model. In each plot, we measured variables such as total tree height (m), diameter at breast height (DBH) (cm) and basal area of larger trees as cumulative basal areas of trees (GCUM) of DBH > 5 cm. The empirical data were analyzed using regression analysis. There was a statistically significant nonlinear function between the annual basal area increment, as the dependent variable, and the basal area of the individual trees and competition as explanatory variables. Reference area from the largest trees, was circular plot with area of 0.1 ha. GCUM was estimated for trees of DBH > 5 cm. Furthermore, we investigated the dependencies of diameter growth of different species on stand density at different levels of competition, and diameter development of individual trees through time. The results indicate that competition caused by larger neighborhood trees has a negative effect on growth. In addition, the maximum diameter increment is affected by competition level. Therefore, the maximum diameter increment of species occurs when the trees are about 35–40 cm in dense-forest (40 to 0 m2 per ha) and when the trees are about 60 to 70 cm in very dense forest (60 to 0 m2 per ha) which is more likely to Caspian natural forests with high level density due to uneven-aged composition of stands.

  • 6.
    Hejazian, Mohammad
    et al.
    Sari Agricultural Sciences and Natural Resources University, Mazandaran, Iran.
    Lotfalian, Majid
    Sari Agricultural Sciences and Natural Resources University, Mazandaran, Iran.
    Lindroos, Ola
    Swedish University of Agricultural Sciences, Umeå.
    Mohammadi Limaei, Soleiman
    University of Guilan, Someh Sara, Iran.
    Wood transportation machine replacement using goal programming2019Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, s. 1-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Farm tractor + trailers play a key role in wood transportation after forests are logged. Despite of the fact that a forwarder is a forestry vehicle that carries felled logs for shorter distances off the ground, tractors are still used in some forest areas of the world, such as the Hyrcanian forest in northern Iran. This study was conducted to investigate the possibility of using both the light forwarder and forestry trailer instead of a farm tractor + trailer in wood transportation. The optimal machine option for wood transportation is determined using goal programming model in the study area. In this paper, multi-objective goals (such as economic, operational, environmental and ergonomic) were considered. The results showed that considering only the economic goal, the contractor could save up to 44% in costs by purchasing and replacing a forestry trailer with a 2-wheel trailer attached to the farm tractor. In addition, considering various goals, a light forwarder could be selected as the optimal machine. Currently, the most important objectives of all forest contractors are to establish economic goals and reduce wood transportation costs. Since other goals, such as environmental and ergonomic, are also important; it is suggested that multi-objective approaches should use for planning.

  • 7.
    Hejazian, Mohammad
    et al.
    Sari Agricultural and Natural Resources University, Sari, Iran.
    Lotfalian, Majid
    Sari Agricultural and Natural Resources University, Sari, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Estimating the economic life of forest machinery using the cumulative cost model and cost minimization model in Iranian Caspian forests2018Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 64, nr 5, s. 216-223Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study was conducted in order to estimate the economic life of two models of rubber-tired skidders, namelyTimberjack 450C and HSM 904, in Iranian Caspian forests. The total annual costs and average cumulative cost ofskidders were calculated by life-cycle costing analysis. The economic life of the machines was estimated by boththe cumulative cost model and cost minimization model. The results indicated that the economic life of Timberjack450C and HSM 904 is 7,700 h (at the end of the 11th year) and 15,300 h (at the end of the 17th year), respectively,using the cost minimization model. Furthermore, the results indicated that the economic life of Timberjack 450Cand HSM 904 is 9,100 h (at the end of the 13th year) and 11,900 h (at the end of the 21st year), respectively, usingthe cumulative cost model. The cumulative cost model estimated the economic life of skidders longer than the costminimization model.

  • 8.
    Lohmander, Peter
    et al.
    SLU, Umeå.
    Mohammadi Limaei, Soleiman
    SLU, Umeå.
    Optimal continuous cover forest management in an uneven-aged forest in the north of Iran2008Ingår i: Journal of Applied Sciences, ISSN 1812-5654, E-ISSN 1812-5662, Vol. 8, nr 11, s. 1995-2007Artikel i tidskrift (Refereegranskat)
  • 9.
    Lohmander, Peter
    et al.
    Optimal Solutions in Cooperation with Linnaeus University.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Stochastic Dynamic Programming with Markov Chains for Optimal Sustainable Control of the Forest Sector with Continuous Cover Forestry2017Ingår i: Iranian Journal of Operations Research, Vol. 8, nr 1, s. 91-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a stochastic dynamic programming approach with Markov chains for optimal control of the forest sector. The forest is managed via continuous cover forestry and the complete system is sustainable. Forest industry production, logistic solutions and harvest levels are optimized based on the sequentially revealed states of the markets. Adaptive full system optimization is necessary for consistent results. The stochastic dynamic programming problem of the complete forest industry sector is solved. The raw material stock levels and the product prices are state variables. In each state and at each stage, a quadratic programming profit maximization problem is solved, as a subproblem within the STDP algorithm.

  • 10.
    Lohmander, Peter
    et al.
    Linnaeus University and Optimal Solutions.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Stochastic dynamic programming with Markov chains for optimal sustainable control of the forest sector with continuous cover forestry2017Konferensbidrag (Refereegranskat)
  • 11.
    Lohmander, Peter
    et al.
    Optimal Solutions.
    Mohammadi Limaei, Soleiman
    University opf Guilan, Iran.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Mohammadi, Zohreh
    University of Guilan, Iran.
    Optimal forest management based on growth data from the Iranian Caspian Forest2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Forest management in the Iranian Caspian Forest is optimized via harvesting decisions based on individual trees. The theory of optimal control in discrete time, stochastic dynamic programming, is applied. The optimization program utilizes new basal area growth and volume functions for beech, estimated via data from the Iranian Caspian forest.

    Recent information about the degree of price variation is used in the optimizations. The optimal control function is defined as a reservation price function, which is determined via backward recursion. The optimal reservation price function and the optimal expected present value function are determined for alternative levels of interest rate and risk. Furthermore, the optimal harvest year and optimal harvest diameter frequency distributions are determined for different degrees of risk and rate of interest. 

  • 12.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Duopsony game theory application in pulpwood market in Iran2008Konferensbidrag (Övrigt vetenskapligt)
  • 13.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Economics optimization of forest management: Economically Optimal Values and Decisions in Iranian Forest Management2011 (uppl. 1)Bok (Övrigt vetenskapligt)
    Abstract [en]

    This book presents the economically optimal values and decisions in Iranian Caspian Forests. The optimal harvest decisions were calculated via stochastic dynamic programming. The harvest decisions that maximize the expected present value of all profits over time are made adaptively, conditional on the latest available price and stock information. The results show that you may increase the expected present value via optimal adaptive decisions. Dynamic game theory was applied in a duopsony situation in the timber market and duopoly situation in the product market in northern Iran. The trajectories of the decision probability combination were investigated. It was found that a large number of initial conditions make the decision probability combination follow a special form of attractor and that centers can be expected to appear in typical games

  • 14.
    Mohammadi Limaei, Soleiman
    University of Guilan, Someh Sara, Iran.
    Efficiency of Iranian forest industry based on DEA models2013Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 24, nr 4, s. 759-765Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Data Envelopment Analysis (DEA) is a mathematical technique to assess relative efficiencies of decision making units (DMUs). The efficiency of 14 Iranian forest companies and forest management units was investigated in 2010. Efficiency of the companies was estimated by using a traditional DEA model and a two-stage DEA model. Traditional DEA models consider all DMU activities as a black box and ignore the intermediate products, while two-stage models address intermediate processes. LINGO software was used for analysis. Overall production was divided into to processes for analyses by the two-stage model, timber harvest and marketing. Wilcoxon's signed-rank test was used to identify the differences of average efficiency in the harvesting and marketing sub-process. Weak performance in the harvesting sub-process was the cause of low efficiency in 2010. Companies such as Neka Chob and Kelardasht proved efficient at timber harvest, and Neka Chob forest company scored highest in overall efficiency. Finally, the reference units identified according to the results of two-stage DEA analysis.

  • 15.
    Mohammadi Limaei, Soleiman
    University of Guilan, Someh Sara, Iran.
    Mixed strategy game theory, application in forest industry2010Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 12, nr 7, s. 527-531Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Two large paper mills dominate the forest industry in northern Iran. Forest companies and local farmers sell pulpwood to these mills. The real pulpwood price data was collected from two paper mills in the northern part of Iran. These mills buy most pulpwood in this area. Game theory has been used in order to investigate the market structure in this region. Game theory is the study of interacting decision makers. Game theory has been widely used in economics. Most economic behaviour can be viewed as a special case of game theory. A game model includes a set of players, a set of strategies and a set of payoffs. This study focuses on the theory of dynamic duopsony games. When pulpwood is sold, the different mills use mixed strategies to give sealed bids. In each transaction, each mill (player) has two different possible strategies (decisions): a high (H) or a low (L) prices. Which price should you set? What is the optimal price of the other player? Here the situation is a noncooperative game. Nash equilibrium and dynamic properties of the system are determined. Each mill continuously observes the frequencies of the other mills action. The expected marginal profits are calculated based on this information. In case the marginal profit of mill A is strictly positive (zero or strictly negative), mill A increases (leaves unchanged, decreases) bids. In case the marginal profit of mill B is strictly positive (zero or strictly negative), mill B increases (leaves unchanged, decreases) bids. It is found that the decision probability combination of the different mills follow a special form of attractor and that centers should be expected to appear in unconstrained games. 

  • 16.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Optimization in Forest Harvesting2008Konferensbidrag (Övrigt vetenskapligt)
  • 17.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Risk management in forestry; Economics perspectives2011Konferensbidrag (Refereegranskat)
  • 18.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Role of Forests in Sustainable Development of Silk Road Countries2019Konferensbidrag (Refereegranskat)
  • 19.
    Mohammadi Limaei, Soleiman
    et al.
    Univ Guilan, Somehsara, Iran.
    Heybatian, Roghayeh
    Univ Guilan, Somehsara, Iran.
    Vaezin, Seyed Mandi Heshmatol
    Univ Tehran, Karaj, Iran.
    Torkman, Javad
    Univ Guilan, Somehsara, Iran.
    Wood import and export and its relation to major macroeconomics variables in Iran2011Ingår i: Forest Policy and Economics, ISSN 1389-9341, E-ISSN 1872-7050, Vol. 13, nr 4, s. 303-307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research is to study the import and export of wood in Iran and determine its relation with major macroeconomics variables such as population, Gross Domestic Product (GDP), world oil price and the amount of domestic wood production. Multivariable Regression analysis (MRA) was employed in order to investigate the relation between import and export of wood with the above mentioned variables. The results showed that there is a significant relation with significant level of 5% between wood import as a dependent variable and population, GDP and the amount of domestic wood production as independent variables. There was also a significant relation between wood export and population, GDP, amount of domestic wood production, and world oil price. Time series analysis and autoregressive procedure were then used to predict the export and import of wood. Results showed that it is possible to predict the wood export via a first order autoregressive model. The mean of the wood export in the distant future was calculated to be 2133.37 tons per year. 

  • 20.
    Mohammadi Limaei, Soleiman
    et al.
    Univ Guilan, Somehsara, Iran.
    Kouhi, Maryam Seddigh
    Univ Guilan, Somehsara, Iran.
    Sharaji, Teymour Rostami
    Univ Guilan, Somehsara, Iran.
    Goal programming approach for sustainable forest management: (case study in Iranian Caspian forests)2014Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 25, nr 2, s. 429-435Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify sequestrated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m(3).ha(-1) for beech, 59 m(3).ha(-1) for hornbeam, 73 m(3).ha(-1) for oak, 41 m(3).ha(-1) for alder, and 32 m(3).ha(-1) for other species. The total optimum volume is 455.25 m(3).ha(-1).

  • 21.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Someh Sara, Iran.
    Lohmander, P.
    SLU, Umeå.
    Obersteiner, M.
    International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria .
    Decision making in forest management with consideration of stochastic prices2010Ingår i: Iranian Journal of Operations Research, Vol. 2, nr 1, s. 32-40Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The optimal harvesting policy is calculated as a function of the entering stock, the price state, the harvesting cost, and the rate of interest in the capital market. In order to determine the optimal harvest schedule, the growth function and stumpage price process are estimated for the Swedish mixed species forests. The stumpage price is assumed to follow a stochastic Markov process. A stochastic dynamic programming technique and traditional deterministic methods are used to obtain the optimal decisions. The expected present value of all future profits is maximized. The results of adaptive optimization are compared with results obtained by the traditional deterministic approach. The results show a significant increase in the expected economic values via optimal adaptive decisions.

  • 22.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Iran.
    Lohmander, Peter
    A game theory approach to the Iranian forest industry raw material market2006Ingår i: Scandinavian Forest Economics, ISSN 0355-032X, s. 225-246Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Dynamic game theory is applied to analyze the timber market in northern Iran as a duopsony. The Nash equilibrium and the dynamic properties of the system based on marginal adjustments are determined. When timber is sold, the different mills use mixed strategies to give sealed bids. It is found that the decision probability combination of the different mills follow a special form of attractor and that centers should be expected to appear in unconstrained games. Since the probabilities of different strategies are always found in the interval [0,1], the boundaries of the feasible set are sometimes binding constraints. Then, the attractor becomes a constrained probability orbit. In the studied game, the probability that the Nash equilibrium will be reached is almost zero. The dynamic properties of timber prices derived via the duopsony game model are found also in the real empirical price series from the north of Iran.

  • 23.
    Mohammadi Limaei, Soleiman
    et al.
    Swedish University of Agricultural Sciences (SLU).
    Lohmander, Peter
    Swedish University of Agricultural Sciences (SLU).
    Optimal continuous cover forest management in an uneven-aged forest in the north of Iran2006Konferensbidrag (Refereegranskat)
  • 24.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions; Linnéuniversitetet.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Dynamic growth models for continuous cover multi species forestry in Iranian Caspian forests2017Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 63, nr 11, s. 519-529Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study concerns some of the relevant topics of the Iranian Caspian forestry planning problem, in particular the first central components in this modelling process, such as forest modelling, forest statistics and growth function estimations. The required data such was collected from Iranian Caspian forests.  To do so, 201 sample plots were determined and the parameters such as number of tree, tree diameter at breast height  and trees height were measured at each sample plot. Three sample plots at different 3 elevations were chosen to measure the tree increment. Data has been used to estimate a modified logistic growth model and a model that describes the growth of basal area of individual trees as a function of basal area. General function analysis has been applied in combination with regression analysis. The results are interpreted from ecological perspectives. Furthermore, a dynamic multi species growth model theory is developed and analyzed with respect to dynamic behavior, equilibria, convergence and stability. Logistic growth models have been found useful in continuous cover forest management optimization. Optimization of management decisions in a changing and not perfectly predictable world should always be based on adaptive optimization.

  • 25.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Iran.
    Lohmander, Peter
    SLU.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Sub Models For Optimal Continuous Cover Multi Species Forestry In Iran2015Ingår i: Proceeeding , 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Forestry in Iran is based on continuous cover forestry (CCF) management principles. CCF often leads to higher expected present values than rotation forestry (RF) with clear cuts. Furthermore, CCF has environmental advantages of several kinds. Many different species of trees grow together in large parts of these forests in Iran. Mixed species forests give advantages compared to monocultures, such as options to adapt harvesting of different species to changes in market prices, climate, species specific damages etc. In order to optimize multi species CCF in Iran, it is necessary to develop mathematical models for operations research studies that represent the relevant parts of the Iranian forestry planning problem. This presentation includes central components in this modelling process: Forest statistics, growth function estimations and the links to forest harvesting, logistics and the forest industry mills.  

  • 26.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Moradi, S.
    Lohmander, P.
    Optimal Solutions.
    Game theory approach for decision making in watershed management2017Konferensbidrag (Övrigt vetenskapligt)
  • 27.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Safari, G.
    Iranian National Tax Administration, Karaj, Iran.
    Mohammadi Merceh, G.
    Islamic Azad University, Rasht, Iran.
    Recreational values of forest park using the contingent valuation method: (case study: Saravan Forest Park, north of Iran)2016Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 62, nr 10, s. 407-412Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research was to evaluate the economic values of Saravan Forest Park, north of Iran. The contingent valuation method was used for this propose. In order to do this research, 480 questionnaires were used. The questionnaires were distributed randomly among the visitors in different seasons. A linear logit regression model was used to estimate the relation between dependent and independent variables. The software including MS Excel, Eviews and Shazam was used for statistical analysis of variables, mathematical calculation and parameter estimation of the logit model. Results indicated that the variables such as proposed entrance fee, monthly income, non-governmental organization membership, moralizing view on the environment and natural resources as well as length of stay have significant effects on willingness to pay for the recreational use of the study area. Results showed that 91.19% of people were willing to pay for the recreational value of the forest park. Results also showed that the total annual recreational value of the forest park is 22,761.6 million IRR.

  • 28.
    Mohammadi Limaei, Soleiman
    et al.
    Univ Guilan, Sowmeh Sara, Iran.
    Safari, Ghazaleh
    Iranian Natl Tax Adm, Karaj, Iran.
    Merceh, Goljahan Mohammadi
    Islamic Azad Univ, Rasht, Iran.
    Non-market valuation of forest park using travel cost method: (case study: Saravan forest park, north of Iran)2017Ingår i: Austrian Journal of Forest Science, ISSN 0379-5292, E-ISSN 1815-3704, Vol. 134, nr 1, s. 53-74Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research was to evaluate the non-market products of a forest park in north of Iran. Required socio-economics data were collected using questionnaires. Travel cost method was used to estimate the economics and recreational values. Regression analysis was used to estimate some socio-economics variables on behavior of forest park visitors. The economics and recreational values of forest park calculated via the demand function. The results of regression analysis showed that the variables such as required time to access the site, travel cost, monthly income, age and education effect on visiting people to the forest park. The results showed that there is a linear relation between required time to access the park and number of visitors. The results indicated that there is a polynomial relation between the number of visitors and the travel cost. The results of regression analysis showed that there is a third degree polynomial relation between the number of visitors and income. Furthermore, the results of demand function showed that the daily value of recreational site or consumer surplus is 68319800 Iranian Rials. The results of this study can be a powerful tool to improve the quality of environmental services and expand service and infrastructure quality of the study area.

  • 29.
    Mohammadi Limaei, Soleiman
    et al.
    University of Guilan, Iran.
    Torkaman, Javad
    University of Guilan, Iran.
    Heshmatolvaezin, Seyed Mahdi
    Market Margin Model of Beech, Hornbeam, Alder and Maple Timbers: Case Study in Iranian Caspian forests2010Konferensbidrag (Refereegranskat)
  • 30. Mohammadi, Z.
    et al.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Multi objective linear programming approach for sustainable plantation2015Konferensbidrag (Övrigt vetenskapligt)
  • 31.
    Mohammadi, Zohreh
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions; Linnéuniversitetet.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Estimating the aboveground carbon sequestration and its economic value: case study: Iranian Caspian Forests2017Ingår i: Journal of Forest Research, ISSN 1341-6979, E-ISSN 1610-7403, Vol. 63, nr 11, s. 511-518Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of the study is to estimate the aboveground carbon sequestration and to determine the economicvalue of forests in carbon sequestration as a way of mitigating climate change. This research was conductedat Asalem forests in the north of Iran. In order to estimate the amount of annual carbon sequestration, theannual volume growth of stand was determined using the diameter increment data and tariff. The amount ofcarbon sequestration was estimated based on wood density and using the allometric equation. The carbonmodel was obtained for each species. The value of sequestrated carbon in stumpage and the net present valueof carbon sequestration were determined in order to estimate the economic value of carbon sequestration.Results indicated that the annual volume growth per hectare and the carbon stored are 6.023 m3·yr–1 and2.307 t·ha–1, respectively. Finally, the carbon sequestration value of stumpage and the net present value ofcarbon sequestration are 11,023.753 and 790.361 (10,000 IRR·t–1·ha–1), respectively. Our results are very usefulin estimating the total economic value of Asalem forests and other Iranian Caspian forests in the future.

  • 32.
    Mohammadi, Zohreh
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Lohmander, Peter
    Optimal Solutions in Cooperation with Linnaeus University, UmeåSweden.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests2018Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 29, nr 5, s. 1205-1214Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests. A survey was conducted in order to find a natural forest without any harvesting activities, a so called ‘untouched forest’ and an area was selected from the Iranian Caspian forest. Three sample plots in the same aspect and of the same forest type were selected. In each plot, total tree height, diameter at breast height, distance of neighbor trees and azimuth were measured. Thirty trees were selected and drilled with increment borer to determine the increment model. Regression analysis was used to estimate the growth model. Results show that, for individual trees, there is a significant nonlinear relationship between the annual basal area increment, as the dependent variable, and the basal area. The results also show that the basal area of competing trees has a positive influence on growth. That the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition, most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare.

  • 33.
    Mohammadi, Zohreh
    et al.
    Univ Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    Univ Guilan, Sowmeh Sara, Iran.
    Shahraji, Taymour Rostami
    Univ Guilan, Sowmeh Sara, Iran.
    Linear programming approach for optimal forest plantation2017Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 28, nr 2, s. 299-307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research was to identify species suitable for plantation. We first identified species for potentially suitable for plantation based on ecological capabilities regarding soil properties. We determined the area of plantation for different species based on ecological capabilities. Then, we collected relevant data such as growth patterns of different species, labor requirements for plantation and plantation cost. A linear programming model and two integer linear programming models were used for optimization. The appropriate species based on ecological capabilities were ash, elm, maple, oak and bald cypress. A linear programming model was used based on ecological capabilities classification to determine the land area of different species for plantation. Then, two integer linear programming models were employed to select the species for plantation. We set ecological properties unequal for all of the species in the first run of the integer programming model. Two groups were classified: group one included maple and ash; group two included bald cypress, oak and elm. The second integer programming model assumed equal ecological properties for all the species. Results of linear programming showed that maple and bald cypress were appropriate for plantation at the site and their plantation areas should be 151.3 and 355.3 ha, respectively. Results of the first integer linear programming model showed that maple and bald cypress would be economically profitable for plantation. The results of the second integer linear programming model showed that only bald cypress would be appropriate for plantation.

  • 34.
    Mohebi Bijarpas, M.
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Rostami Shahraji, T.
    University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Socioeconomic evaluation of agroforestry systems: (Case study: Northern Iran)2015Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 61, nr 11, s. 478-484Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research was to investigate the socioeconomic values of different land use in the agroforestry system. Questionnaires were used to collect social and economic data in two villages at Guilan province, northernIran. Internal Rate of Return (IRR) and Profitability Index (PI) were used for cost-benefit analysis. Net Present Value(NPV) of different farming systems was determined. ANOVA test was used to compare the outcomes of different landuse. The results indicated that there is a significant relationship between literacy and variety of land use in two villages. Results of IRR and PI indices show that these indices were higher in poplar plantation than in the other land use(paddy and tea field, horticulture and vegetable). Results of ANOVA test showed that there is a significant differencebetween net incomes from different farming systems in Tamchal village. Furthermore, the ANOVA test showed thatthere is no significant difference between net incomes from different farming systems in Narenj Bon Paeen village. Theresults showed that farmers tend to participate in training and promoting classes associated with the maximum use ofland. Chi-squared test was used in order to determine the effect of participation in training and promoting classes onmultiple uses of land, land use change, sericulture, and apiculture. The results of Chi-squared test showed that thereis a significant and positive relationship between people’s participation rates and the multiple use of land. In overall,results showed that traditional agroforestry systems provide a higher income than monoculture in the study area.

  • 35.
    Moradi, Sohrab
    et al.
    Payame Noor University, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Multi-objective game theory model and fuzzy programing approach for sustainable watershed management2018Ingår i: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 71, s. 363-371Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study was carried out with the aim of feasibility evaluation of the application of multi-objective game theory and fuzzy programing approaches for settling balance between economic development and environmental impact as well as to facilitate the respective decision-makings in Zemkan basin, west of Iran. The bi-objectives of multi-objective game theory and fuzzy programing approaches are minimizing the destructive effects on the environment (less erosion and sediments) and maximizing the economical incomes resulted from different land uses (more net present value). Satellite images were used for recognition of different land uses and the areas of these land use. In this study, the environmentalists and Zemkan basin users were selected as environmental and economical players, respectively. The results reveal that Nash bargaining solution, which is the result of the multi-objective game theory model, differs from Pareto optimalities, obtained through the classical multi-objective model. Nash bargaining solution offered more satisfactory solutions based on decision-makers’ priorities. In addition, the overall results showed that the results of fuzzy programming approach were very close to the results of the multi-objective game theory model. Therefore, in both methods, the decision variables of semi-closed forest, open forest, non-irrigated agricultural lands and barren rocky lands were eliminated and the ones of rural areas, urban areas, and water body remained unchanged. The innovation of multi-objective game theory and fuzzy programing approaches, which can be understood and interpreted well by decision makers, is setting a kind of balance between economic and environmental concerns in watershed management. The results also show that multi-objective game theory and fuzzy programing approaches can be applied to many other issues concerning the environmental management. The upcoming researches can concentrate on developing a third objective like social concerns and accordingly tri-objective games would be applied instead of bi-objective ones.

  • 36.
    Moradi, Sohrab
    et al.
    Payame Noor Univ, Tehran, Iran; Univ Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    Univ Guilan, Sowmeh Sara, Iran.
    Lohmander, Peter
    Swedish Univ Agr Sci, Umeå.
    Khanmohammadi, Mehrdad
    Univ Guilan, Sowmeh Sara, Iran.
    Quantitative and financial evaluation of non-timber forest products: (case study: Zemkan basin forests, West of Iran)2017Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 28, nr 2, s. 371-379Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although Zagros forests in western Iran lack industrial timber value due to the severe climate and socioeconomics problems, non-timber products are of great value and importance due to their high economic potential and also their potential to improve the welfare of forest-dwelling and forest-fringe villagers. This study was done in the forests of the Zemkan basin, an important part of central Zagros forests, Iran, to recognize the non-timber forest products (NTFPS), investigate their potential economic value and role in people's livelihood. Data, collected using forest cruising, participatory observations, interviews with indigenous and local persons and experts, identified wild pistachio resin, wild pistachio fruit, oak fruit and oak syrup (Shokeh manna) among the non-timber products in this basin with total potential harvestable NTFPs of 77.16, 771.602, 13248.68, and 1324.868 tons per year, respectively. The economic rent from NTFPs is 33 US$/ha/year and its total expected values with consideration of real interest rate when the exploiter invests the capital in the bank (6.4 %) and when money is borrowed from the bank to execute the incorporated projects (8.4 %) are $516/ha and $393/ha, respectively. Furthermore, families' economic share from potential profit of NTFPs is annually $601 per household. In addition wild pistachio resin has the highest share of the total potential profit of NTFPs and its equal to 51 % of the total of potential profit of NTFPs. Therefore, it is suggested that decisions be made to increase the infrastructure and strengthen the local selling market to enhance the cash income from NTFPs. Forest participatory management practices are suggested to organize and improve traditional use of the forests.

  • 37.
    Moradpanah, Haniyeh
    et al.
    Islamic Azad University, Lahijan Branch, Lahijan, Iran.
    Dehdar Dargahi, Mohammad
    Islamic Azad University, Lahijan Branch, Lahijan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Moradpanah, Monireh
    Islamic Azad University, Science and Research Branch, Tehran, Iran.
    A socio-economic evaluation of a protected area: A case study: Hamadan province, Iran2016Ingår i: Environmental & socio-economic studies, ISSN 2354-0079, Vol. 4, nr 2, s. 9-16Artikel i tidskrift (Refereegranskat)
  • 38.
    Namdari, Samaneh
    et al.
    Lorestan University, Khoramabad, Iran.
    Adeli, Kamran
    Lorestan University, Khoramabad, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Bahramabadi, Zahra
    University of Guilan, Sowmeh Sara, Iran.
    Risk assessment in poplar plantations: a case study from northern Iran2019Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, s. 1-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Linear risk programming was used to determine the optimum cultivation pattern to increase incomes of poplar farmers. Seven clones of Populus deltoides Bartr. ex Marsh. were examined in Guilan province, northern Iran. Growth and price data were taken from previous research at the Safrabaste Poplar Research Station and in interviews with farmers. The Lingo software was used to analyze the data in different forms of E. The results show that when risk was considered, the optimal solution included the clones Pd63/51-x1, -Pd72/51-x3, Pd73/51-x4 and Pd79/51-x6. There was a high growth fluctuations of the clones Pd69/55-x2, Pd77. 51-x5, and Pd caroliniensis-x7 and were not included in cultivation plans. Furthermore, the existing farm plans executed by local farmers, is neither profit-oriented nor efficient in terms of income risk management according to risk efficient frontier. These results could help farmers with different levels of risk-aversion to select proper planting plans.

  • 39.
    Sotoudeh, Bahman
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Rostami Shahraji, Taymour
    University of Guilan, Sowmeh Sara, Iran.
    Assessment of logging moratorium using analytical network process in Iranian Hyrcanian forests2019Ingår i: Journal of Sustainable Forestry, ISSN 1054-9811, E-ISSN 1540-756X, Vol. 38, nr 2, s. 130-148Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research is to evaluate three forthcoming scenarios (continuing of forest management plans, logging ban, and forest management plans halt) in terms of policy change and select the best method based on sustainable forest management strategies in Iranian Hyrcanian forests. For this propose a two-layer evaluation process was considered for choosing the best alternative. Analytic network process as a decision approach is applied with Benefit- Opportunity-Cost-Risk (BOCR) merit. The data were obtained either from the previous research or through questionnaires. The results indicated that the benefits and risks were more important in terms of decision-making, compared to the opportunities and costs. Finally, the scenario of 'continuity of forest management plans' was selected as the most suitable alternative. The decision framework proposed in this study offers a rational means for decision-making of forest policy.

  • 40.
    Sotoudeh Foumani, S.
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Rostami Shahraji, T.
    University of Guilan, Sowmeh Sara, Iran.
    Investigation of wood production and trading in Iran2016Ingår i: Journal of Forest Science, ISSN 1212-4834, E-ISSN 1805-935X, Vol. 62, nr 9, s. 407-412Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The relation between wood export and import of Iran and a number of major macroeconomic variables,such as oil price, gross domestic production, population, exchange rate, unemployment rate, inflation and domesticwood production during 1980–2014 were described. Pearson’s correlation coefficient and multiple regression analysiswere used for data analysis. The results showed that there is a significant relation at a significance level of 5% betweenwood export as a dependent variable and oil price, GDP, population, exchange rate and domestic wood production asindependent variables. Meanwhile, there is also a significant relation between wood import and oil price, exchangerate and domestic wood production. The findings also indicate that oil price as an independent variable has the highest effect on wood import in Iran during the studied period.

  • 41.
    Torkaman, Javad
    et al.
    University of Guilan, Iran.
    Vaziri, Mojgan
    Luleå University of Technology.
    Sandberg, Dick
    Luleå University of Technology.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Relationship between branch-scar parameters and knot features of oriental beech (Fagus orientalis Libsky)2018Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 13, nr 2, s. 117-120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The classification of roundwood is inextricably linked to the measurement of a particular single wood defect. The appearance, location, and number of defects are important in the quality evaluation of logs and sawn timber, and the most important defects are knots. The purpose of this study was to investigate the relationship between the appearance of branch scars and features of the related knot inside oriental beech logs, and to model the relationship between well-defined branch-scar and knot parameters. One hundred and fifty knots in 15 stems of oriental beech trees were studied. Image analysis software was used to measure the branch-scar and knot features. The results showed a significant positive correlation between the branch-scar parameter “moustache length” and the knot length. The ratio of branch-seal length to width was found to be a good estimator of the stem diameter at the time of knot occlusion and the amount of clear wood between the knot occlusion and the bark. The relationship obtained for the oriental beech stem radius at time of knot occlusion confirms relationship reported for European beech (Fagus sylvatica L.).

  • 42.
    Zadmirazaei, Majid
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Amirteimoori, Alireza
    Islamic Azad University, Iran.
    Assessing the impact of the external non-discretionary factor on the performance of forest management units using DEA approach2017Ingår i: Journal of Forest Research, ISSN 1341-6979, E-ISSN 1610-7403, Vol. 22, nr 3, s. 144-152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this paper is to measure the relative performance of forest management units, and to analyze the impact of the external non-discretionary (ND) factors on these units' technical efficiency. Toward this end, data envelopment analysis (DEA) technique in variable returns to scale environment with both discretionary and ND factors has been used. The required data are collected from 24 Iranian forest management units (as decision-making units (DMUs)) and included four inputs and two outputs. The ND factors are first ignored and it is shown that most of the forest management units are operating at high efficiency levels. Then the variable area is considered as the exogenously fixed (or the external ND) input in a modified ND model because it is outside of the forest manager's control. The results indicate that the number of efficient units and the average technical efficiency score are reduced to 12 (approximately 50%) and 0.85, respectively. The forest management units should therefore increase their average efficiency score by 0.15 to move onto the new efficient frontier which is made by applying this strict criterion. As a consequence, it is recommended to apply the ND models for controlling the exogenously fixed factors and carrying out a correct and accurate evaluation, because the traditional DEA approaches may overestimate the efficiency of DMUs.

  • 43.
    Zadmirzaei, M.
    et al.
    Univ Guilan, Gilan, Iran.
    Mohammadi Limaei, Soleiman
    Univ Guilan, Gilan, Iran.
    Amirteimoori, A.
    Islamic Azad Univ, Rasht Branch, Tehran, Iran.
    Efficiency Analysis of Paper Mill Using Data Envelopment Analysis Models: (Case Study: Mazandaran Wood and Paper Company in Iran)2015Ingår i: Journal of Agricultural Science and Technology (JAST), ISSN 1680-7073, Vol. 17, nr 6, s. 1381-1391Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, the relative performance of Mazandaran Wood and Paper Company as a major supplier of paper products in Iran was measured. Network Data Envelopment Analysis (DEA) models with parallel structure were used to evaluate and measure its performance. GAMS software version 23.4 was used for data analysis. Results indicated that this company in all studied years had good performances based on the parallel DEA models. Also, according to the same models with parallel structure, 2007 and 2008 had better efficiency score than the other years. Finally, results indicated that, using the cross efficiency models, the company had the best performance in 2007. This result could be due to the input-oriented nature of the models. Consequently, by proper management and optimum consumption of the resources, the company had the best performance in 2007.

  • 44.
    Zadmirzaei, Majid
    et al.
    University of Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Sowmeh Sara, Iran.
    Amirteimoori, Alireza
    Islamic Azad University, Rasht Branch, Rasht, Iran.
    Olsson, Leif
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Measuring the relative performance of forest management units: A chance-constrained DEA model in the presence of the non-discretionary factor2019Ingår i: Canadian Journal of Forest Research, ISSN 0045-5067, E-ISSN 1208-6037, Vol. 49, nr 7, s. 788-801Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, we develop a marginal chance-constrained data envelopment analysis model in the presence of non-discretionary inputs and hybrid outputs for the first time. We call it a stochastic non-discretionary DEA model (SND-DEA), and it is developed to measure and compare the relative efficiency of forest management units under different environmental management systems. Furthermore, we apply an output-oriented DEA technology to both deterministic and stochastic scenarios. The required data are collected from 24 forest management plans (as decision-making units and included four inputs and equal amount of outputs. The findings of this practical research show that the modified SND-DEA model in different probability levels give us apparently different results compared to the output from pure deterministic models. However, when we calculate the correlation measure, the probability levels give us a strong positive correlation between stochastic and deterministic models. Therefore, approximately 40% of the forest management plans based on the applied SND-DEA model should substantially increase their average efficiency score. As the major conclusion, our developed SND-DEA model is a suitable improvement over previous developed models to discriminate the efficiency and/or the inefficiency of decision-making units to hedge against risk and uncertainty in this type of forest management problems.

  • 45.
    Zadmirzaei Soleimandarabi, Majid
    et al.
    University of Guilan, Iran.
    Mohammadi Limaei, Soleiman
    University of Guilan, Iran.
    Amirteimoori, Alireza
    Islamic Azad University, Rasht, Iran.
    Deterministic Scenario vs. Stochastic Scenario in Data Envelopment Analysis (DEA): A Case on Iranian Forest Management Units2018Konferensbidrag (Refereegranskat)
  • 46.
    Zandi, Solmaz
    et al.
    Univ Guilan, Sowmeh Sara, Iran.
    Mohammadi Limaei, Soleiman
    Univ Guilan, Sowmeh Sara, Iran.
    Amiri, Neda
    Univ Guilan, Sowmeh Sara, Iran.
    An economic evaluation of a forest park using the individual travel cost method (a case study of Ghaleh Rudkhan forest park in northern Iran)2018Ingår i: Environmental & Socio-Economic Studies, ISSN 2354-0079, Vol. 6, nr 2, s. 48-55Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The true economic value of ecosystem services may not be reflected in market transactions, because there is no real transaction for ecosystem services in the market. Therefore, it is important to evaluate the cost of time and travel to define the value people place on something in the absence of a market price. This study estimates the recreational value of Ghaleh Rudkhan forest park in the north of Iran using the individual travel cost method. This method is considered to be a substitute approach for the market. The data required were collected using questionnaires. Therefore, 271 questionnaires were randomly distributed between the visitors of the recreational site in 2016. In this study, a linear function is used to estimate the effects of explanatory variables including economic and social variables on the number of visits to estimate the recreational value of the forest park. Results showed that a consumer surplus of each person for their visit was 21500 Rials and the annual recreational value of the park was 78390595 Rials per ha. Furthermore, the variables such as travel expenses, income, distance, family size and visitor's age are effective factors in the recreational use of the park. The results of this study can improve the quality of environmental services of the Ghaleh Rudkhan forest park and could expand the variety of services that they could supply based on the demand of the people.

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