Year:2002 | Volume:14 | Issue:4 (53 IN NATURAL RESOURCES)|Papers Count:28

In order to comparison of afforestation and selection of the best Acacia species and determination of their irrigation period, this plan carried out in Sarkhoon research station on 40 Km. far north of Bandar Abbas in 1994. Acacia species are important for browsing and animal nutrition, medicinal and industerial consumption, soil conservation, ecosystem equilibrium and feul supplies. The lay of this experiment was a split plot design with 6 irrigation as a main factor and 4 Acacia species. Irrigation treatment are, A: only one time has been irrigated, B: Irrigation interval every 10 days, C: irrigation interval every 20 days, D: Irrigation interval every 30 days, E: Irrigation interval every 40 days and F: Irrigation interval every 50 days. Different Acacia species are, a: A. nilotica, b: A. ehrenbergiana, c: A. tortilis and d: A. oerfota. The survival of seedlings were counted in the end of every month, according to statistical analysis of fourth year there are significant differences at levels of one and five percent between different species and irrigation treatments. There is no significant difference between treatments which have common lines. Therefore F (irrigation interval every fifty days) for a, b, c (A. nilotica, A. ehrenbergiana, A. oerfota) and A (only one time has been irrigated) for c (A. tortilis) are recommended.

Planting of Atriplex canescens in desert regions has been successful during recent decade. The research was conducted in Zarand-e- Saveh and Myghan desert regions. Before seed harvesting, phenological stage of this species was recorded.Then according to maturation stages of seed collection was carried out for determination of moisture percentage, thousand grains weight and germination percentage, complete rondom design was used in 4 replicates and 3 treatments. The results showed significant effect in different harvesting time of germination of A. canescens in Zarand-e- Saveh region; however different harvesting time had no significance on seed germination of A. canescens in Myghan region. The best period seed harvesting for A. canescens occurred when seed moisture-content was 6 percent and thousand grains weight was 8.92 gram and germination was 60.5 percent. In general seed moisture content, seed germination, thousand grains weight were important characteristics for determination of seed harvesting time.

In this survey base of scientific sources and field observation in Khuzestan province 570 endemic species of Noby - Sindy and Irano - Turani were studied. From these, 180 species were introduced as medicinal plants in the books and grocerys of the province so far. Matchless variety of plants specially medicinal plants in different parts of the province are caused by the variety of climate. In view of climatic conditions, Khuzestan province has four zones of growth: Warm steppe, warm semisteppe, dry forests and country pastures. Each zone has its own special medicinal species. Spreading of some species are in a particular altitude habitat, but the others have wide spreading in the province and change of alt and rainfall rate does not have too much effect on them. In this survey on the base of study of plant therapeutic culture and field observation introduce of major medicinal plants of the province about 20 endemic species were distinguished to be medicinal that less mentioned in the scientific sources.The primary study of phenology of some medicinal plants in Khuzestan made provide a model of harvesting time table.

Sample of teak (Tecton agrandis), keruing. (Dipterocarpus alatus), Balau (Shorea sp.), Chengal (Balanocarpus heimii king) were treated by coal tar oil (Creosote) using Ruping method. The retention of creosote in each species were 188, 186, 331, 40 kilogrames per cubic meter. Treated and untreated (control) samples were inspected according with recommendation of IRG/WP 4432. During This installation in sea water according to IRGWP 4432 During 6, 9, 20, 23, 26, 28 months, the samples were installation period after 9 months m control samples of teak and, balau were slight attacked. After 23 month, immersion, all the treated samples were slight, attacked and after 28 months installation in sea water, all the treated samples destroyed by marine borers. The severity attack of chengal samples less than the others.

There are a number of morphologic and with high correlation to essential oil yield of various of the plant species. A correct understanding of these effects would cause improvement in strategies to increase leaf and, flower essential oil yield of the species. In this study path analysis was applied within some morphologic and phonologic characters recorded from field studies conducted in the year of 2000 on four Menthe species at Research, Institute of Forests and Rangelands Analysis of flower essential oil related characters revealed that percentage of leaf essential oil and leaf length had a high direct effect on the dependent variable, flower essential oil yield. Flowering time showed a positive direct effect but a high negative total indirect effect through other independent variables on dependent variable, resulting in a negative total effect on essential oil yield. Analysis of leaf essential oil related characters showed that both stem diameter and flower essential oil yield had almost equal positive direct effect on leaf essential oil yield Flowering date showed negative direct and total indirect effects on leaf essential oil yield. Stem length had high positive indirect effect on the leaf essential oil yield through independent variables counterbalancing negative direct effect to a counterbalancing negative direct effect to a positive total effect of 0.487.

Non endemic species have been planted in north of Iran from 30 years ago in .this investigation, the effects of ecualyptus spp. plantation on undergrowth community was studied and compared with effects of populous plantation (in Shikhneshin) and Cupressus arizonica plantation (in Saravan). Some characters of soil such as soil texture sodium content, potassium content, organic% matter, EC and pH were measured. Sodium and potassium content was measured by flame photometer. EC and pH was measured in saturated extract of soil. Organic% matter was measured by dry ashing method. Results indicated undergrowth community of eucalyptus plantation and populus plantation had 45% difference according to Sorenson formula and undergrowth communities were heterogenous. Also potassium content in eucalyputs plantation is more than populus but less than Cupressus arizonica plantation. %Organic matter in eucalyptus plantation is more than Cupressus arizonica plantation but less than plantation. Soil acidity in eucaliptus plantation was more than other plantation. Results indicated that ecological parameters in ecualyptus plantation had more effect than kind of species on undergrowth community from west to east of Gilan province.

The lack of data on sediment yield of watersheds in Iran has lead to use of emperical methods to estimate the amount of sediment; PSIAC is one of such methods. This method was used in five catchments in the west Azarbaijan province. The data on river load during 20 years was analysed. "t" student method was used to test of significance of difference among means. Results showed that in four case of five catchments, there was not a significant difference between the mean of estimated sediment yield and the mean of sediment load analysed in gaged stations.

Flowering part of Origanum majorana L. cultivated in national botanical garden of Iran was collected in Aug. 1999 and after confirming by the Herbarium of the research institute of forests and rangelands, steam distilled for 45 min. to produce an oil of 0.3% yield (based on dry weight of flowers). The oil was analyzed by GC and GC/MS. Twenty-four compounds were identified, among which linalyl acetate-(26.1 %) and sabinene (12.0%) were the major constituents.

Measuring biodiversity is a difficult task and takes a lot of cost and time. There is not a standard protocol for biodiversity measuring. In order to conserving biodiversity in northern forest of Iran, this study investigated a method for measuring woody plant diversity witch with minimum time and cost consumption could determine and comparisons the species richness with desirable presice the woody plant diversity was inventoried by using multi scale whittaker plots modified for northern forest of Iran with completely random distribution in distinctive forest types. The data from plots were used to compute species-area curves by using linear regression between species number and log area the species-log area curve equations were corrected by Jaccard coefficient that accounts for the overlap between two complete species lists. The validity of obtained equations was evaluated and validated by comparisons of observed number of species recorded in plots and estimated number of species by equations. The results represented high accuracy in estimating woody species richness in all types.

Required number of female flowering branches from two species of Papulus nigra and P. delta ides were placed in water and soil in a greenhouse on late February and early March 2000. Female flowering branches were also grafted on one year old seedling stocks of the species, before catkins elongation and exposition, planted in the plastic pots. Pollen was collected in suitable times from appropriate male plant branches, being kept in different cool temperature. Pollination was done by a fine brush on the female flowers several times per day for two to three consecutive days to make sure all parts of the catkin flowers receive enough pollen. Mature hybrid seeds were directly sowed well moisture soil. Embryo rescue technique was also used to develop the immature hybrid seeds and embryos. Free growth regulator half MS, MS and B5 agar medium were used to perform the technique. Six leaved seedlings were transplanted in well incubated soil.

Burning of nearly 700 Kuwaiti oil wells and storage tanks during the Persian Gulf war made a server impact on the environment of the region by emitting about 5000 tons of smoke daily. The fall out of smoke plumes in forms of dry and wet deposition reached even to the center and north of Iran. The majority of the rich and productive rangelands in the southern parts of Iran were strongly marked by pollution to various degrees. Generally, the polluted rainfall was spread over the whole natural vegetation in 1991. Since nobody was prepared to record the impact and consequence of that environmental catastrophe, so, remotely sensed data were selected as a good information source to assess the short term effect of the pollution on the natural vegetation cover. For this study, out of various change detection techniques, spectral change analysis method with special emphasis on vegetation indices was selected. The NDVI (Normalised Difference Vegetation Index) was used for natural vegetation cover change detection in this study because of its acceptable accuracy and ability to detect the green vegetation. To a certain extent of decision, the methodology was made on the basis of availability of data, particularly the satellite images. As a result, it was found that integrated use of remotely sensed images with different resolutions also with support of available ground data and statistical analysis is a reliable approach to detect the impact of environmental pollution on vegetation growth, particularly when the event is not accessible in term of time. This study showed that natural vegetation cover was significantly decreased in the areas where have been affected by pollution during the Persian Gulf War in 1991.

In order to drive soil moisture characteristics curve in watershed management, irrigation and drainage, hydrology, and all this project of soil and water order is very important and inavoidable. Driving soil moisture characteristics curve to specify the project requires operational activities of pertaining to desert, laboratory work, spending time and expenditure. Much effort has been done to predict in this project considering physical characteristics of soil, such as soil texture and bulk density all easily available and acceptable. Camp bell has presented top equations of soil moisture curve with special regards. In this research, Camp bell equations of soil moisture curve shows resembling with callibration. Physical characteristics of eight types of soil samples measured in zone of Varmine, consisting soil texture, bulk density and soil moisture characteristics curve. With use of new triangular soil texture presented by Shirazi and Boersima, and presentation of Campbell equation with more information and statistical data of experiments to make effort with callibration of Campbell equations and modeling soil moisture characteristics curves. Results from this project indicating with callibration, shows in presentation of equation having standard error in six cases from eight cases of soil samples and only two cases having more standard error of equations, reduction can be found out from physical characteristics like structural of soil and organic matter, also Campbell model shows in low pressure suction having less standard error compared to upper pressure suctions, Because in low pressure suctions, the size of the porespace plays a major role in remaining water in soil. Since geometric mean diameter of soil is one of the main parameters in Camp bell model, therefore this model works precise in low pressure than high pressure suctions. Also in this research it was noted in 15KPa suction pressures or wilting point the standard error (SE) was decreased again due to (S) shape of moisture curve. Campbell equation model of moisture curve primary point and in end having better conformity reduce due to accuracy of middle zone.

Interaction of waves and currents is a complicated phenomena in seas and oceans. Variation in coastal morphology is the results of waves, currents, and sea bed sediments dynamics. Shear stress due to waves and currents is one of the basic formulas to estimate the longshore sediment transport. In this paper we will present some new ideas about the longshore sediment transport models, which was very good compared by the so called Bijker formula.

In order to study and monitoring of the regeneration trend in forest region of "Langa", 186 sample plots were laid -out in form of nested plots. Main plots had an area of 300m2, subplots 50m2 and micro plots were 5m2 area. All trees with dbh>15cm, regeneration (seedlings) lower than 1.3 m and samplings (higher than 1.3m) has been studied in each plot more over the vigority and qualitative condition of seedlings and samplings has been studied. The regeneration area had 553 ha surface and included 11 compartments. The results could be summarized as following: - Compartment 207 showed the lowest proportion of seedlings (3800/ha), while compartment 201 showed the high.est (48400/ha).- Beach (Fagus orientalis)showed the highest proportion (54%)among the regeneration of tree species. The lowest proportion recognized by Alder (Alnus subcordata). - About 89%of young individual was made of seedlings (h<1.3m), while only 1.3% was recorded in dbh (7.5-12.5cm) class. - Although, the aim of the management plan was obtaining uniform, even aged stands, but the stands show still uneven aged profile. - The regeneration has been established in groups. Some parts of the regeneration area have natural regeneration and are covered with fern / blackberry and other weeds.

Mineral composition and the degree of weathering of bulk composition of soils and rocks are the most important parameter in the evaluation of geotechnical properties, erodibility and other physical properties. There are some methods for evaluating the effect of weathering on mechanical characteristics of soil and rocks. Also, many models have been suggested for estimating the sediment yield of the watersheds using the evaluation of bulk composition of original minerals and the degree of weathering. Thus, evaluation of weathering processes and their effect on the generation of secondary minerals is one of the main interests of soil scientists. The original mineral of the upper part of earth’s crust was generated under special condition of temperature, pressure and chemical composition of their sources. However, they are un-stable under present condition at the surface. The surface soils and rocks have more simple and stable chemical compositions than original minerals. But they have very different geotechnical properties and erodibility. For example, the present instability of many slopes could be due to the progress of weathering and generation of new clay contents in rocks and soils. A new method of weathering evaluation using the secondary mineral content will be reported in this paper.

Conventional in vitro micropropagation has been used to produced planlets, but its widespread still restricted as a result of its relatively high production costs and disorder physiological plant development due to use of exogenous hormones. The inclusion of sugar as a carbon source in culture media has resulted in high contamination. Photo autotrophic micriopropagation is a new technique in which plants are growing in a CO2 enriched atmosphere under high light intensities. Three experiments were carried out to elucidate the influence of different culture conditions and environmental factors on growth of E. camaldulensis. The use of defined supporting material, media and other conditions described in this study gave significantly better growth rates parameters in this species. Despite adding media to the culture vessel under non - sterile conditions, no microbial contamination was observed in this system. Results in the other experiments showed that the relative growth rate was substantially increased as temperatures were raised from 20±1oc to 24±1oc and different explants sizes gave the same pattern of growth rate, therefore, the smallest explants could be used Photoautotrophic micropropagated plantlets were successfully acclimatized.

Micropropagation of Populus caspica using bud culture was investigated. The effect of sterilization, treatments growth regulators and media on establishment and multiplication of explants were studied. The best sterilization treatment was observed in 70% ethanole solution for 30 seconds following6 min dipping in 0.1%HgCl2 solution. MS medium containing half strength of nitrate, 0.01mg/lit IBA and 0.5 mg/lit BA were chosen for culture establishment and shoot multiplication. The highest rhyzogenese observed in MS medium supplemented with 0.5mg/lit IBA. Transferring of these plantlets to steril soil (Peat/Perlit/sand) in equal percents and graduality acclimatization was done successfully. Now there are two years old plants in the fieldwith4 to 6 meter height.

Because of the useful chemical composition, F. gummosacan playa basicrolein therapeutic uses. This survey was carried out during 1994-1997, to receiving the preliminary information about planting and generation of F. gummosa in Semnan Natural Resources Research Center. In this research, different sowing methods (interseeding, scattering, pots sowing) some climate factors effect, survival percentage and transferring time from the pots to field were compared. This survey was performed in six distinct tests and the following results were obtained: 1- Seed germination needs to cold weather. 2- Snow is an important factor for seed germiantion.3- Altitude from the sea level affects in seed germanition. 4- Plant loss percentage mean was 38.2% until third year. 5- Interseeding methods and pots sowing were superior to the scattering one.6- Sown pots could be transferred to the area in the second year.

The purpose of this study was to assess the role of extension in participation of farmers in land consolidation projects in province of Semnan. The sample for this study was 153 farmers (72 participants and 81 non participants). The research design included a survey strategy and a questionnaire was developed. Data were analyzed using regression analysis, the wilcoxoxmann-whitneyTest (MW.Test) and chi-square. The results of the study shows that the factors "Education, knowledge of farmers about land consolidation, membership with cooperatives and rural organizations, role of rural leaders, number of educational extension classes, and type of ownership of lands" had meaningful relationship with participation in land consolidation. It was also found out that factors "age, income, using extension Journals did not have any impact on land consolidation in the province of Semnan. The study arrived at two main findings:First, the educational and extension classes were effective in convincing farmers to participate in land consolidation. Second, farmers have indicated that extension journals did not have any impact on changing their attitudes about land consolidation