نشریه علوم و فنون منابع طبیعی
سال پنجم شماره 3 (پاییز 1389)

Forest parks are classified into the category of non-market goods and they don’t have market price, thus there is no scale for comparing their value with other goods. This study has been conducted in 2008 to determine recreational value of Tangeh forest park, With an area of 32 ha located near Minodasht city, Golestan province, which plays an important role in urban management, using the survey data and the referendum approach from park visitors. This park has a Revision Plan. The results showed that 70.18 percent of visitors were leaning toward paying the entrance fee for using its recreational facilities. Also, 38.6 percent of Tangeh forest park visitors assess its recreational value more than 1000 Rials per person per visit and 12.28 percent of visitors stated that its value is more than 2000 rials and 7.02 more than 5000 rial known. Finally, the daily recreational value of this park is estimated 619143 Rials for all that area and 19348 Rials per hectare per day. The results revealed that the recreational value of forest parks is more important and play multiple roles in passing leisure time of the population. Furthermore, forest parks are very much valuable economically and recreationally which needs a plan for their in come.

This research was done in order to study and determine the quantity of the useful mineral components in leaves and finding out leaf parameters such as leaf area , wet and dry weight , dampness percentage and the leaf area proportional to its mass in usual conditions for pistcia mutica trees in the forest area of mah Parviz pass in Yasuj on a slope altitude of 1850–2600 meters. In this research 30 pistacia mutical trees were selected and 4 leaves from each base in four geographical directions were selected and totally there were 120 leaves. sampling was entirely random in four geographical directions. The samples were selected from different heights the lower, ceteral and upper part of the crown of pistacia mutica trees. Meanwhile the special leaf area and the mineral components of the leaves were determind in the laboratory, too. the results obtained analysing the leaves show that the samples from pistacia mutica in the dry material were (92.04%), Ca(1.47%), P(0.12%), K(0.99%), Na(0.005%), Mg (0.74%), CU (2.48%) and N(0.43%).The results obtained from studying the special leaf area and changes show that the ratio of the dry and wet weight in different geographical directions and different parts of the trees crown don’t show glaring differences, but the special leaf area shows a noticeable difference in different parts of the tree crown and different directions in a case that in the north an south directions in a dry state the special leaf area at the upper part of the tree crown in order are between 68.9 to 79.1 and 66.6 to 76.6 square millimeters and in a wet state 33.3 to 38.5 and 33.8 to 39.8 square millimeters and in the east and west directions in dry weight state are respectively 55.1 to 63.6 and 62.4 to 68.6 square millimeters and in wet weight state the differences are between 33.3 to 34.3 and 30.2 to 37.2 square millimeters.

Due to the high importance of forest gaps, this research investigated soil conditions in forest gaps. Oak – Hornbeam stands with an area of 87 ha were selected for this purpose in Sarcheshmeh forests, Chalous. To study the gaps, we selected five gap sizes that consist of very small (200 m2), small (400 m2), medium (600 m2), large (800 m2), and very large (1000 m2) ones and every one with four replicate and control point in 25-30 meters distances. To investigate soil characteristics, three soil profiles of 50*50*45 sizes (with the pickup of organic layer and mineral soil in three depths 0-15 cm, 15-30 cm, and 30-45 cm) were selected random methods and were separated in edge and central positions of every gap. In this research we studied soil characteristics that consist of water content, carbon, nitrogen, C/N ratio, phosphorous and pH soil. The results showed that with the increase of gap size in the central position the amount of water content, carbon, C/N ratio and phosphorous decrease. Also pH soil has statistical linkage with gap size and the highest level of pH was observed in very large gaps. The highest amount of soil characteristics were on surface layer and except to pH, the other characteristics decreased while soil depth increased.

Corrugated board is considered a valuable commodity for packaging at both international and domestic markets. therefore it is necessary to identify the consumption and production patterns as well as the most important and effective variables on it for the development of corrugated board production industry in Iran and understanding the variation in demand for this product, Based on this information it can be forecasted. In this study, the dynamic econometric model has been used to demonstrate simultaneous relationship between supply and demand. Coefficients of the model were estimated applying 3SLS procedure with the time series data from 1981 to 2007. In this respect before estimating equations Augmented Dicky-Fuller (ADF) test was used for the analysis of the variables cointegration at 5% significant level.The study results indicated that in the demand function, the variables including, intercept, price,GNP in the previous period, Population, CPI, industrial added value IAV and the war dummy are significantly different at 0.05% level. However, in the supply function, intercept, production ,consumption and import quantity in the previous period, inflation rate, cost price in the previous period simultaneously influence consumption and production.

In order to investigate the anatomical properties of wood, three normal planted maple trees from Chamestan area in Nour have been selected, samples from the pith to bark in the longitudinal direction of the trees (under 1.30m) (5m) (10m) have been prepared and tested. The results indicated that in the surface of one millimeter in a square, the average vessels density was 31, average wood ray density was 31 rays, and in the longitudinal direction of the trees from down to top it showed the 95% confidence level between the first and second discs in comparison to the third one with regular increase. The vessel diameter has been measured to be 65-70 microns and shows relatively regular decrease in the longitudinal direction of the trees from down to top at the level of 95% confidence, between the first and second discs in comparison to the third disc with regular increase, a significant differences was observed. Vessels diameter has been measured to be 65-70 microns and relatively regular decrease has been observed in the longitudinal direction from down to top. A regular trend has been observed for the width of wood ray cells and in the longitudinal direction of trees an irregular trend has been observed for the length of wood rays. The number of wood rays rows from down to top, though showing an irregular decrease did not show a significant difference.

In this study, the effects of quantity and type of lignocellulosic reinforcement on the physical and mechanical properties of wood polymer composite were studied. To meet this objective, two types of lignocellulosic materials include of wood flour and cotton fiber were mixed with polypropylene at 30, 40, 50 and 60 percent of weight rations, also 2 percent of MAPP as the coupling agent in all formulatins was used. Then the composite was manufactured by injection molding, and the physical and mechanical tests were performed on samples according to ASTM standard. The result indicated that, the flexural strength, flexural modulus, tensile strength, tensile modulus, water absorption and thickness swelling of composite were increased by increasing lignocellulosic reinforcement, but the impact strength were decreased. In addition, mechanical properties and water absorption capacity of composite made of cotton fiber is higher than wood flour.

Nowadays, the undeniable role of environment in the economic activities of human societies has introduced the term sustainable development in the world literature. Sustainable development is a kind of development that tries to solve present generation need and considers next generations needs and enjoys different dimensions such as economical, environmental and social. CDM is a long-term view point this means that developing countries get to better life standards for themselves. So, in this research after introducing sustainable development by using proform software, economical analyzes for wood and paper industry is calculated and the amount of influence accomplished for optimization. and also by using CDM project for sustainable development standards in this industry and finally by using energy and environment software social prices of each of pollutant gases were calculated according to EPA. Results show that by replacing Boiler with higher output, at the of 6360 Thousand GJ, it will economize on the consumption of fuel. It is supposed that (project’s age is 12 years) during this date the diffusion of green house gases will be eliminated at the amount of 30 HT. considering the amount of invest tment needed which amounts to 385 thousand $ and 12 years effectiveness of the project will reduce all kinds of green house gases at. the amount of 360 thousand tons. Therefore, this study in wood and paper industry of Iran in addition to increasing efficiency will maintain sources of fossil energy in the world which can help to reach sustainable development standards.

In this research, some chips of bamboo stem in the western part of Mazandaran (Noshahr region) were randomly chosen and CMP Pulps were prepared at the yield of 85% in 120 minutes, then by using cooking conditions of Wood and Paper Industries of Mazandaran, newsprint papers were prepared from the bamboo CMP and Mill(MWPI) CMP pulps, first in a separate and then in a mixed way. After that the hand made newsprint was prepared of 60 gr per each square meter. Then, the optical and mechanical properties were measured and compared based on TAPPI Standard test methods. The results showed that most of the strength of the burst, breaking length, tensile, fold and tear strength were in the handsheets obtained from 100% of bamboo CMP pulp. The lowest strength (except brightness and roughness) was in CMP pulp Mill. The results also pointed out that the above-mentioned features (except brightness) can be improved by using 25-100% of bamboo CMP pulp, too. The results also indicated that 25-100% of the bamboo CMP pulp can replace some of the CMP pulp of MWPI Mill.

Industrial waste water usually has metal ions which could be dangerous over the optimum level for human and other animals. In this study the removal of metal ions such as lead, copper and zinc with tree leaves from waste water was investigated to introduce the cheap, effective and touchable adsorbents as compared with trade absorbent marks. For this reason 5gr of seven softwoods leaves such Beech, Oak, Alder, Mapel, Hornbeam, Walnut and Hazel were selected from the western part of Mazandaran providence, Then 200ml wastewater containing metal ions such as lead, copper and zinc were prepared in specific concentrations and then regulated in pH= 5. Then the removal of metal ions from wastewater were tested in 30, 60, 90, 120 and 150 minutes. The result indicated that there are significantl differences between species and various times in the removal of metal ions in 99% confident levels; however Beech leave had the highest removal rate of lead, copper and zinc as 51.89, 39.69 and 29.90 percent respectively. Also the optimum level of connection times for the removal of metal ions from hardwoods leaves are 90 minutes. The results revealed that beech leaves are more efficient in removing of metal ions, as compared with laboratory adsorbents (active carbon).

Possessing some of four protected regions, Guilan Province enjoys one of the most valuable ecosystems of Iran. Because of numerous values and the importance of these four regions of the province in the structure of ecosystems, a strong management and a legal system based on the environmental situation of these regions are necessary. Considering these four regions which are under the management of Iran Department of Environment from legal and environmental viewpoints, most of the problems and challenges of these regions seem to be destruction and occupancy of lands, unauthorized hunting. conveyance and change of function, irregular grazing, tree cuts, fire incidents and illegal constructions. There are legal principles and rules in manuals and in the regulations of four regions which provide obligations and require sanctions to protect the regions, but undoubtedly some legal drawbacks are obvious in the regions because of increasing complicated environmental problems and challenges to protect renewable natural resources of Guilan Province especially in these four regions. Researches show that such these regulations should be econsidered because of their drawbacks such as disproportionate punishments and crimes, lack of necessary sanctions to avoid any aggression to these regions, conveyance of regions by governmental sector and lack of coordination among beneficiaries.

Pollutants have various direct and indirect adverse impacts on the environment, including water quality changes as well as changes in benthic organisms distribution. Therefore, the quality of water can be assessed by sampling aquatic environments and their benthoses .Studying and assessing the structure of benthic communities in aquatic ecosystems have a remarkable role in the ecological assessments of the aquatic organisms. The importance of benthoses is not only because of their existence in the food chain, but also because of existence or non-existence of some of benthic species which can show the quality of water in terms of the amount of pollution or nonpollution .Gorganrood is situated in Golestan state. It oriinates from Golidagh highlands in Golestan National Park and then after crossing Gonbadkavoos and AghGhala located in the west of KhajehNafas,it enters the Caspian Sea. Due to flood breaking out in the rainy months of the year causing severe turbidity ,as well as the high flow rate of Gorganrood river, the density of the benthoses is less than the other rivers .Among various macrobenthoses ,14 families have been recognized whose highest densities belong to Diptera (Chironomidae) and Oligochaeta (Tubifix). One of the reasons of species enrichment reduction and the density and the abundance of macrobenthoses in the above-mentioned river is the lack of appropriate vegetal coverage along the river. Pollutants, and sewages resulting from human and natural pollutions due to the improvement of country industries and establishing several factories along the river and their water consumption along with releasing sewages to the river without filtration can cause significant danger for the aquatic organisms. Due to high flow rate and turbidity seen in the upper parts of the river, the amount of benthic organisms shows less density. Upstream stations are more influenced with water features. The water of the river is polluted while flowing and mixing with urban and rural sewages, particularly Gonbad sewages .The amount of such pollution is various based on different flow rate of water. The station lacks natural water flow in summers and only a stream of urban and rural sewages can be seen. The results achieved from Saprobic and Hilsenhoff methods with physical parameters show such a problem.