Year:2005 | Volume:18 | Issue:3 (68 IN NATURAL RESOURCES)|Papers Count:12

The water budget modeling is an important primary task in hydrologic studies of lakes and reservoirs. With the aid of the water budget equation, one can calculate the amount of free surface water evaporation. This method was used to determine evaporation from the Chahnimeh Reservoir in Sistan region, east of Iran. Nine years of daily inflow and outflow, water surface fluctuation, rainfall, and pan evaporation data were used in this study. A detailed investigation showed that daily water budget survey is not appropriate because of extreme fluctuation of water surface. Therefore, 5-day, 10-day, and monthly time steps were selected to form the water budget equations. The water budget equation was used to calculate pan coefficient in two cases: Annual and time dependent within the year. A regression model was formed to determine the coefficients. The model was confirmed by F test in 99 percent significant level in development phase and was verified by K2 test in 99 percent significant level in the evaluation phase, except for the monthly time step due to insufficient number of samples. Classification of data into two homogeneous groups, dry years and normal wet years, showed that pan coefficient decreases during the 120days wind blowing in Sistan from May to October. The reduction in pan coefficient is larger, by as much as 50 percent, in the dry years than normal-wet years.

The study was carried out to survey the effects of Atriplex canescens on soil physiochemical characteristics in Aghzi Gang region of Zarand-Saveh. Considering the research objective, samples were taken from 8 areas in which were planted with A. canescens and 8 no planted (control) areas. Because of dense accumulation of Atriplex shrubs, quadrate area was determined 6*8 m2. Quadrates were placed upon randomized-systematic method. Within quadrates, in addition to vegetation variables estimation, soil samples were taken, too. In A. canescens planted areas, soil samples were collected from two depths (0-20, 20-40 cm) under shrubs and opening, while in control areas, samples were taken from 0-20, 20-40, 40-60 and 60-80 cm layers. Measured soil characteristics included texture, pH, EC, lime, organic matter, potassium, nitrogen and phosphorus. The results show that in plantation areas with A. canescens, soil properties such as amount of potassium, phosphorous, nitrogen, pH, and EC show an increase at depth of 0-20 cm and with increasing depth, plantation effects decreased. In total, plantation effects of A. canescens on soil properties in the study region were evaluated positive.

The essential oils isolated by hydro-distillation from the leaves of Eucalyptus torquata and Eucalyptus leucoxylon were analyzed by GC and GC/MS. The main components identified in E. torquata oil were 1,8-cineole (63.3%), α-pinene (11.1%) and (Z,E)-farnesyl acetate (7.8%), and in E. leucoxylon oil were 1,8-cineole (88.9%), terpin-1-o1 (3.7%), the oil yield were 1.11% and 1.54% respectively. The chemical composition of the oils with high content of 1,8-cineole are classified as a "eucalyptol or medicinal" type. This paper now reports for the first time the results of the analyses of leaf essential oil of E. torquata and E. leucoxylon which have been adapted after ten years in southwest of Iran.

The Geno protected area with 27500 ha located in 30Km west north of Bandar Abbas. The view of area is mountainous region that located among plains and hills. Altitude domain of area is between 50 to 2347m. The flora of area belonged to Sahara-Sindian and Irano-Turanian regions. This investigation was done for collection and determination of medicinal plants of Geno protected area. By regard to source, aware and informed persons and visible observations were determined 124 medicinal species and were noted some of information as: Persian, local, scientific and family name, altitude, part used, reason and method of uses for all of plants. This medicinal plants beloged to 100 genus and 52 families, that the most species were in Labiatae (17 species) and Compositae (10 species) families. 95 species had traditional cure uses, 29 species were with many uses and 11 species were exported to arabic countries.

In this investigation, poplar wood (P. nigra) for medium density fiberboard (MDF) production and determining of anatomical characteristics of P. nigra, mechanical and physical properties of boards have been studied. Variables factors such as streaming time in three levels (15, 20 and 25 minutes), press time in three levels (4,5 and 6 minutes) and resin content in two levels (9 and 11 percent) were investigated. The results of this study showed that average fiber length and diameter of the P. nigra measured at 1048 and 21.21µ respectively. The results indicated that with increasing steaming time, internal bonding and modulus elasticity of boards decreased. However these properties with increasing of press time, increased. The maximum bending strength, modulus of elasticity and internal bonding were related to MDF boards produced after IS minutes steaming time, 6 minutes pressing time and 9 and 11 percent resin consumption. The maximum thickness swelling after 2 and 24 hours soaking in water of boards obtained at the same combination.

Prosopis cineraria and Acacia tortilis (Mimosuseae) are of the main trees and shrubs of coastal plain of Hormozgan province. They produce a lot of twigs and pods annually, which used by livestocks such as goats and camels. Therefore determination of their nutritive value are important. In this study three localities of the mentioned species habitats are chooded, 240 samples of two parts of plants (twigs and pods) were collected and after mixing and coding 60 sample (5 samples of each part of each species from three region) were prepared and analyzed chemically. Crude protein (CP), ether extract (EE), crude fiber (CF), ash, calcium and phosphorus in Prosopis twigs were, 10.16, 1.6, 23.5, 9.8, 2.5, 0.07, in prosopis pods were, 15.12, 1.13, 16.6, 5.18, 0.69, 0.12, in Acacia twig and pods were, 16.6, 2.4, 18.3, 6.8, 0.72, 0.19 and 21.6, 0.73, 21.1, 7.9, 0.92, 0.21 percent respectively. The digestibility of DM, OM, CP, CF and NFE in Prosopis twigs were 55.74, 57.69, 40.52, 51.57, 69.52 and in Prosopis pods 60.98, 62.16, 48.08, 51.3, 71.08 and Acacia twigs were, 58.71, 61.73, 50.7, 37.91, 78.17 and in Acacia pods 64.56, 67.06, 47., 54.29, 80.85 respectively when they were determined on mature male goat.

Diversity is one of the most important ecological factors to show changes in ecosystems. In this study, first of all the area of Meyghan playa with 28000 ha which is located 15Km far from Arak city (in Iran) was collected. Then the component of diversity such as species richness, species diversity and equitability were applied to measure the species diversity of each halophyt's association in this area by using to Diver and Nucosa computer programs- Packages Species diversity also were analysed by diversity models such as Geometric, Logaritmic, Lognormal and Broken-stick models using these computer programs pakage. The results indicated that Limonietum iranici has highest diversity fitted with Lognormal series and Nitrarietum schoberi has lowest diversity fitted with Geometric series. The main effective ecological factors on the diversity change are electrical conductivity, amount of Mg2+ and Gyps, Soil texture, percent of organic carbon, ground water level. Factor analysis was applied to recoqnize main ecological fecognize by using Statistica software program package.

The Afratakhteh yew (Taxus baccata L.) habitat with an area of 352 ha is located at the South- eastern of Aliabad city, the lowest and the highest of its elevation are 1350 and 2000 meters. Flora of this region includes 97 plant species that belong to 86 genera and 51 families, of these, 7 species are endemic of Iran. The important families are Asteraceae, Rosaceae and Papillionaceae with 13.04%, 10.87%and 6.52% respectively. Life form of the plant species of Afratakhteh yew site in Runkaier classification Hemichryptophytes, Phanerophytes and in Suzuki- Aracane sub classification Hemichryptophytes with one stem (HC) and Decidous trees (DML) are dominated. From the view point of regional elements plants of this region include: 28.57% Europe- Siberian. 14.29% Irano- Touranian. 11.91% Polyreginal (Europe- Siberian, Irano- Touranian, Mediterranean, Pontic and Iran- Anatoli). 10% Euxine- Hyrcanian. 9.52% Hyrcanian and 25 % remained belong to varios Biregional plant determined.

The studies of pulping technology help the pulp maker to have desired properties, from which one can make the paper grades with desired end-use properties. Recently there is more tend for having lower kappa number in order to use lower chemical in the bleaching unit and reduce environmental pollutions. This is a research of kraft cooking, with Eucalyptus camaldulensis wood at the different effective alkali charge and the same cooking time- temperature and liquor to wood ratio for all. Objective of study was to investigate the effect of effective alkali charges on yield- kappa number- rejects and residual alkali that is one of the cooking variables. Current trend toward lower kappa number is interest in modified pulping. This study discusses the changes needed in cooking variable in order to make a modification on kraft cook. The results showed that changes in EA concentration significantly affected on yield and kappa number. The decreased kappa number provided a pulp with lower screen rejects. In this research- it was found the higher EA concentration affected in the kraft cook In order to improve that with the lower kappa number and desire pulp yield.

Vanak region, has a 40000 hectare area, and a part of mountainous regions of the south of Isfahan province and this region is also 190km far from the south of Isfahan and 33 km west of Semirom. Its elevation ranges is between 1650 meter to 4034 meter above sea level. In this research for the first time, the floristic compositions of the area were studied and 649 plant species belonging to 80 family and 340 genera were identified. From these, the main family and the main genus were detected as Asteraceae with 84 species and Astragalus with 23 species, respectively. Furthermore, the plant life form spectrum showed that these plants consists of 45.37% hemicryptophytes, 30.86% therophytes, 9.26% phanerophytes, 8.96% geophytes, 5.25% chamephytes and 0.30% hydrophytes. From the plants identifid, 121, 119, 115, 81 and 61 species belonged to rare, medicinal, pastural, poisonous and woody species, respectively.