Goal programming approach for sustainable forest management （case study in Iranian Caspian forests）

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 seques- trated 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 m3.ha-1 for beech, 59 m3.ha-1 for hornbeam, 73 m3.ha-1 for oak, 41 m3.ha-1 for alder, and 32 m3.ha-1 for other species. The total optimum volume is 455.25 m3.ha-1.     

Effects of Salinity and Water Stress on Echophysiological Parameters and Micronutrients Concentration of Pomegranate (Punica granatum L.)

In order to study the effects of salinity and drought stress on echophysiological parameters and micronutrients concentration of pomegranate leaves, a factorial experiment was conducted based on completely randomized design with 0, 30, and 60 mM of salinity levels of sodium chloride and calcium chloride (1:1) and three irrigation intervals (2, 4, and 6 days) with three replications on ‘Rabab’ and ‘Shishegap’ cultivars of pomegranate. The results analysis of shoot and root indicated that the water salinity and drought affected the concentration of iron (Fe²⁺), zinc (Zn²⁺), copper (Cu²⁺) and manganese (Mn²⁺) in pomegranate leaves and roots. Mineral concentration of zinc (Zn²⁺), copper (Cu²⁺) and manganese (Mn²⁺) in roots and manganese (Mn²⁺) in shoot was increased with increasing salinity. Drought treatments decreased the concentration of Zn²⁺ in the shoot and increased Zn²⁺ in roots. Both cultivars showed significant differences in the Fe²⁺ concentrations of shoot, however the most accumulation of Fe²⁺ was observed in ‘Shishegap’ cultivar.     

Linear programming approach for optimal forest plantation

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.     

Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests

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.     

Efficiency of Iranian forest industry based on DEA models

Data Envelopment Analysis (DEA) is a mathematical tech-nique to assess relative efficiencies of decision making units (DMUs). The efficiency of 14 Iranian forest companies and forest management units w...     

Effects of Salinity and Water Stress on Growth and Macro Nutrients Concentration of Pomegranate (Punica granatum L.)

In order to study the effects of salinity and water stress on growth and macronutrients concentration of pomegranate plant leaves, a factorial experiment was conducted based on completely randomized design with 0, 30, and 60 mM of salinity levels of sodium chloride and calcium chloride (1:1) and three irrigation intervals (2, 4, and 6 days) with 3 replications on ‘Rabab’ and ‘Shishegap’ cultivars of pomegranate. The results of the shoot and root analysis indicated that the salinity and drought affected the concentration and distribution of sodium (Na⁺), potassium (K⁺), chloride (Cl^?), calcium (Ca²⁺), magnesium (Mg²⁺), and phosphorus (P⁺) in pomegranate leaves. Mineral concentrations of sodium (Na⁺), chloride (Cl^-), potassium (K⁺), in shoots and roots were increased with increasing salinity. Drought treatments increased the concentration of Cl^?, Na⁺, and Mg²⁺ in the shoot. Both cultivars showed significant differences in the concentrations of elements, however the most accumulation of Na⁺ and Cl^? was observed in ‘Rabab,’ while the ‘Shishegap’ cultivar had the most absorption of K⁺. ‘Shishegap’ cultivar showed higher tolerance to salinity than ‘Rabab’ through maintaining the vegetative growth and lower chloride transport to the shoot, and improvement of potassium transport to shoot.     

Gelation of iota-carrageenan and micellar casein mixtures under high hydrostatic pressure

Effects of high-pressure treatment (HPT) on the rheological parameters and gelation of iota-carrageenan (iota-Car) and mixtures of micellar casein (MC) and iota-Car have been investigated under neutral pH conditions. It was established that HPT showed no significant effect, in the presence or absence of ionic calcium, with or without initial thermal processing, on the rheology or gelation/melting temperatures of the pure iota-Car solution. However, in mixed systems containing varying concentrations of iota-Car (up to 1 wt %) and MC (up to 8 wt %), considerable changes were detected. At the higher molar ratios of MC to iota-Car, and especially at the higher pressures, the dispersions were not thermoreversible in gelation, presumably due to the strong interactions of disrupted casein micelles with iota-Car molecules, as well as due to the formation of a dominant proteinaceous network at higher concentrations of MC. The associative protein-polysaccharide interactions in these systems are highly dependent on the ionic calcium content.     

High-pressure-induced rheological changes of low-methoxyl pectin plus micellar casein mixtures

The influence of high-pressure treatment (HPT) (200-800 MPa, 5 or 20 min, at 20 degrees C) on the rheological properties of solutions of amidated low-methoxyl pectin (LMP) and its mixtures with micellar casein (MC) has been investigated in the presence and absence of sucrose. The storage modulus G' of LMP gels containing 0-55 wt % sucrose and 0.1-1 wt % LMP was found to increase significantly following HPT at >or=400 MPa. Various concentrations of LMP in the presence of different amounts of MC (0.5-12 wt %) showed contrasting types of rheological behavior. In the presence of a low concentration of LMP (<0.3 wt %), HPT was found to induce a sol-gel transformation at relatively high LMP/MC molar ratios (<4 wt % MC), to reduce values of G' and the loss modulus G' ' at intermediate LMP/MC ratios (4-10 wt % MC), and to increase the values of G' and G' ' at low LMP/MC ratios (>10 wt % MC). In contrast, in the presence of a higher amount of LMP (>0.5 wt %), it was observed that HPT enhances the values of both the storage and the loss moduli over the whole range of MC concentrations.