Year:2007 | Volume:20 | Issue:3 (76 IN NATURAL RESOURCES)|Papers Count:29

Based on latest developments on the environmental valuation studies, attributing an economic value to various provided products and services by forest covers is considered as be an effective management tool for conservation policies. In fact, all non produced assets which benefit human societies and other relevant live communities are the outcome of several complicated ecological processes and ecosystem functions, as well. Being aware of the forest ecosystem roles in soil protection, preventing their resource degradation may lead the affecting stakeholders to a more transparent decision making processes in land use planning measures. This paper which is a small section of a broader research work on Primary Caspian Forests Valuation is intended to have a look on the role of these types of ecosystems in protecting the soil resources and will summarize the existing different methods of quantifying such a function. Meanwhile, by focusing on three large under-management forest areas in the north of Iran, an experimental method will be introduced to value the soil protection function of Caspian forests from the economic point of view. Analyzing the information released by application of the method demonstrated the necessity of a rapid intervention to conserve remaining forest areas in the north of the country. These forests are faced very substantial challenges of land use changes and if there is no action to be taken by public authorities, their permanent degradation and depletion will be unavoidable in coming future.

The main objective of this research was to develop a method for cultivation of indigenous an exotic species via establishing the live medicinal plant gene bank. This collected plant species would help to prevent endanger of native medicinal plants, distinguish and adapt of divers species. The outcomes of this research lead to education and executive practices. This research has been carried out since 2000-2006 in collection of medicinal plants in Yazd province. During this plan, 206 species including 165 genera and 63 families have been cultivated. The seeds and seedlings were prepared from nature, research institute of forest and rangelands, research centers of provinces and a few import species. These plants were planted by direct or indirect (greenhouse and nursery) in different seasons, when they grew large enough were handled to main place. In this way plant the date of germination, stablishment. phenology and compatibility with Yazd climatic condition have been studied. in addition to familiarity with propagation method. The plant pests and diseases, water and fertilizer requirements, drought tolerance and weeds have been surveyed as far as possible. In this research of 206 species medicinal plants have been planted. So 160 species (77.7%) out of them completed their phenology, 24 species (11.6%) are growing, 4 species (1.9%) germinated and them died and 18 species (8.7%) never germinated. There were identified 40 weed species including 23 annual species and 17 perennial species belonging to 14 families. Also 31 pets species and 3 disease species were found on farm plants.

Considering the population growth in the third world countries and people’s need to food, employment, housing and other infrastructural requirements as well as the importance of environmental issues and the role of forests in the sustainable development of ecologies, we can suggest protection of forests and their proper utilization and development along with their economic, social and cultural values are part and parcel of forestuy affairs. In order to achieve the above–mentioneal targets, forestry projects are being carried out of which 50 percent is governmental, 15 percent cooperative and the rest belongs to the private sector. After more Than 15 years of the execution of these projects, the present article deals with the performance of project executors from the viewpoint of foresters. Totally 97 person were randomly selected as a sample of foresters who live in sari region Covered by private, governmental and cooperative executors. Data collection was done by questionaire confirmed by related specialists. Its reliability was determined through kronbakh alfa 85% the research result indicated that people’s cooperation with the governmental sector is for move than that of the other two sectors. It also revealed that the three sectors are quite different regarding the degree of presrvation, rerival and utilization of forests. The result of this research indicated that the governmental sector is more efficient than the other two sectors in forestry affairs.

This research was conducted to determine the wild service tree seed source effect on, seedling growth in a mountainous nursery. Two seed sources, named Sangdeh (1600 to 1800 meter above see level) and Ashak (2100 to 2300 meter a.s.l) were selected in central forest of Mazandaran province in Iran. Seeds of forty individual wild service tree were collected and planted in a mountain nursery named Orimalek. Thirty of one year old seedlings of forty selected mother trees planted in a randomised complete block design with three replications in an area named Farim and located at 1550 meter a.s.l. Ten seedlings from each one of the forty mother trees were randomly allocated to each replication on a row. Survival, collar diameter, height growth and the length of greatest branch of seedlings were recorded. The results of the end of 3th years indicated that the effect of seed sources on seedlings survival and seedlings growth was significant (p<0.01). Seedlings survival and growth of Sangdeh mother trees was more than the survival and growth of seedlings from Ashak mother trees. However, different between Ashak 20 individual mother trees was significant in their seedlings survival, collar diameter, height growth and length greatest branch of seedlings (p<0.01). The same results were seen between Sangdeh 20 individual trees, exception in seedlings survival. Even so Sangdeh source was selected as suitable site for seed collection, but many of mother trees from Ashak source can be candidate as seed trees, because of that, their seedlings survival and growth characteristics was the same as Sangdeh mother tree or more than them.

This research was carried for investigation on relationship between ecological factors and natural distribution and density of Zhumeria majdae from 2001 for two years. Zhumeria majdae is one of the important, unic and endemic species of Hormozgan province that is used for diarrhoea, stomachache, cold, headache, wound and as coolness from ancient times by natives people of Hormozgan. In this investigation, distribution map, climatic, soil and geologic Characteristics and landuses were provided and also vegetative parameters as height, aerial cover density, and percent of aerial cover per hectar were measured. This species located in maintainous region on rocky slope from 450–1400 m of sea level. Habitat soil is sandy loam with EC=0.89-1.1 mm/cm and pH=8.3–8.5. The minimum and maximum of absolute temperature of habitat were zero and 50 centigrade.

To evaluate the effect of sowing date and plant density on grain yield, yield components and morphological characteristics of Nigella sativa, an experiment was conducted at Research Station, Agricultural Education Centre of Islamabad- Ghayein (eastern part of Iran), in growing season of 2003. Four sowing dates (29 Mar., 13 Apr., 29 Apr. and 14 May) and four plant densities (50, 150, 250 and 350 plant/m2) were compared in a factorial experiment based on randomized complete block design with four replications. Different characteristics such as grain yield, plant height, biomass, 1000-seed weight, number of capsule per plant, number of grains per capsule, number of branches per plant and number of inflorescences per plant were recorded. Results showed that sowing date had significant effects on grain yield, biological yield, plant height, 1000 seed weight, harvest index, number of capsules per plant and number of seeds per capsule. Second and forth sowing dates produced the highest (450.3 kg/ha) and the lowest (90.7 kg/ha) grain yield, respectively. By increasing plant density grain yield increased. The highest (468.7 kg/ha) and the lowest (93.1 kg/ha) grain yield were obtained at 350 and 50 plant/m2. Plant density did not have significant effects on biological yield, plant height, 1000 seed weight, harvest index, number of capsules per plant and number of seeds per capsule. Our results showed that the second sowing date with 350 plant/m2 produced the highest grain yield (775.3 kg/ha).

This study was carried out to investigate the possibility of partial replacement of MWPI forest based wood material composition(75%hornbean+25%beech) by using poplar for newsprint production. The species witch used as poplar (populus euramericana), beech (Fagus orientalis) and hornbeam (Carpinus betulus) were used. As the above mentioned poplar at growing period of 8 years old, has been prepared from Safrabasteh research station in Gilan province.Beech and hornbeam chips were prepared from MWPI production line. For pulping, wood as raw material in four combination consist of: pure poplar, mixture of beach and hornbeam, mixture of hornbeam and poplar and also mixture of beech and hornbeam and poplar were used. Based on the results of experimental tests, cooking conditions were applied as 20% chemicals ( based on oven dry wood), cooking time of 90 min, cooking temperature of 160oC, L:W = 7:1 was selected in order to obtain pulping yield of about 85%. After cooking chips were defibrated in three stages and then refined by laboratory beater (PFI mill) to 300 ml. CSF. At last was investigated properties of pulp produced. The results show that, using from poplar as pure or in admixture foresty species for making newsprint will have some positive effect in technologic and economic aspects. Ideal mixed treatment could be recommended as 65% hornbeam+ 10% beech+ 25% 8 years old poplar.

There are several methods to recharge ground water resources, Such as flood water spreading. Ground water recharge, soil improvement and vegetation cover increasing are some of the flood water spreading goals of flood spreading may increase soil moisture and will increase forage production. In this study the effect of flood water spreading on quantitative changes of vegetation cover is evaluated. This investigation is done in aquifer of Herat district of Yazd province that on studying year (2005) it is calculated parameters Such as vegetation cover percentage, production, density and frequency in quadrats. Production is measured in clipping and weight method. The flood spreading area includes 11 fields which just 3 of 11 fields are flooded. In every flood totally 3 times floods were spread in Spring. Observation area included 3 fields. As results indicated flood water spreading, increased vegetation cover, production, density and frequency in flooded area.

Exploitation of seasonal floodwater is very important for arid and semi-arid regions. Suspended particles in flood water change the soil properties. Hormozgan province is located in semiarid region. In this investigation effects of seasonal floodwater on soil properties of Sarchahan area in north of Hormozgan province were studied. In this study three line of spreading network which have high water were selected. Each line divided to three rectangular area which along diameter of them samples of soil profile were taken from three depths ranges including 0-20, 20-40 and 40-60 cm. In each line 18 profiles samples were taken from three area of each rectangular including (1) the area affected by flood and sediment (2) the area affected by flood (3) non – affected area (control group). The result showed in the first area sand is lower, silt and clay are higher than the others two other areas. Salinity, Na+, K, Ca, Mg, CL, SO42-, HCO3-, and SAR in the first area also are higher than the other two areas. Salinity, Na+, K, CL and SAR in the first area are significantly higher than two others (p>%1).

Cytogenetic studies were performed on 17 populations of 10 atriplex species. The video image analysis system was used for determining karyotype species. The basic chromosome number was X=9 for all of the populations but their ploidy levels were varied. On the basis of Stebbins’ method, all of populations were placed in symmetric class of 1A, that indicated the symmetrical karyotype (considering inter chromosomal and intra chromosomal). The Results of analysis of variance based on completely randomized design (CRD) proved that there were significant differences among genotypes for all traits (p<%1). Using principal component analysis, the first two components justify %98.75 of total variance. In the first component, length of the short arm and total length of chromosome had the highest coefficients of eigen vectors. In the second component centromer index, total form percentage, arm ratio and length of the long arm were the most important part in creating of total variance. By cutting dendrogram resulted from cluster analysis (Ward) in distance 2.87, the populations classified to four classes. The highest metric distance obtained between A.aucheri and A.halimus. There was the lowest distance between A.leucoclada (Yazd) and A.nitens (Haraz1). The diagram of the populations distribution, based on two main components, classified the populations in four separated classes, which was in agree with results of claster analysis. The results of cluster analysis (UPGMA) based on 2 parameters (A1 and A2) in distance 1.83, the populations classified to three classes. The highest distance was obtained between A.aucheri and A.lentiformis (Yazd) which imply the lowest affinity between them. There was the lowest distance between A.micrantha and A.tatarica.

Bald cypress (Taxodium distichum (L.) Rich) known as southern cypress or swamp cypress in native to much of the southeastern U.S. This species is decidous conifer with height and D.B.H 1-1.7 m and 40 m respectivly. A study was carried out with this species in Haft daghanan in Guilan provience. The objective of this study was to determine effects of different distance of planting on growth The expermental design used is a randomized complecte block design (RCBD), with 3 replication and 4 planted distance (2´1.8), (2´2), (2´2.5) and (3´3) m. Analyses of variance were carried out and results showed that: * There was not differences between planted distance and height and D.B.H growth. (p>%5). Mean anual height and D.B.H in all of trees was 47 cm and 6 mm respectively. Mean of survival rate was 84.5%. Mean basal area was 16.28 m²/ha. and Rate of h/d was 77.8.

Study of fire effects on forest structure, species composition and stablishment of regeneration gives valuable information about vegetation circumstance after fire. On the other hand, it could be possible to imagine fire destructions and how can we help the forest reclamation. The study area was burnt at 1998 by high severity surface fire and this study was done 7 years later in 2005. After determining the study area in the both of burnt and unburnt area, tree and forest attributes were collected by using a random- systematic grid of plots. The regeneration characterestics also were recorded by 4 microplot per plot. Each plot and microplot area was 1000 m2 and 25 m2, respectively. The result showed that fire decreased number per ha of trees and canopy cover percentage and increased percent of dead trees in the burnt area. There was no significant difference as total number per ha of regeneration between burnt and unburnt area but for number per ha of each species regeneration there was significant difference. The fire however could not change unevenage circumstance of forest but changed compositon of species and forest structure by destroying of low diameter trees and stablishment of more light demanding species such as maple instead of shade tolerant species such as beech in the burnt area. High percent of dead and unsafe trees after 7 years shows that the forest could not be reclaimed within this period of time and silvicultural operatoins for stablishment of favorable species regeneration are needed.

Haloxylon sp, is a plant that growing in arid regions, especially in sand lands as a useful plant for fixinig of sand dune. This plant has economical, social and environmental significance. Mycorrihza is a natural symbiosis between plant root and mycelia of fungi. This symbiosis is important for the plant under stressful, for example,water and nutrient deficiencies. Mycorrhizales symbiosis in Haloxylon was studied in man-made forests Sabzevar plain of Khorasan province.Effect of environmental factors variation such as climate and soil on mycorrhizae were determined. The conclusion showed that H. aphyllumm and H.persicum living in haresabad area was more than an other areas forest. In this symbiosis, the spicies of glomus and acaulospora in man- made forrest make a contribution.

Echium amoenum as oxtongue flower in iranian traditional medicine has been used as tonic and tranquillizer. The aqueous extract of Echium amoenum, can be considered as an effective and safe treatment for major depressive disorder. This species has ditrubiution as wild in north of Iran and cultivated in this regions and Qazvin province. In order to study effect of irrigation intervals on flower yield of Echium amoenum an experiment was conducted in Alamut medicinal plant station in 1997-2000. Design layout was complete randomized block (CRBD) with four treatments interval irrigation: 0, 7, 14 and 21 day and three replications. Results showed plant growth was reduced by increasing intervals. Irrigation schedule also influenced flower yield. The highest flower yield were from plants with the shortest irrigation intervals, equal 420 kg/ha. The highest flower yield in all of treatments concept to second year. The lowest yield obtained without irrigation that was 135 kg/ha. Irrigation increased flowering duration. Flower duration in 7 days was higher than two equal in comparison with non-irrigation condition. Water use efficiency (WUE) in second year for 7, 14 and 21 days irrigation intervals were 70, 98 and 91 gr dried flower per each cubic meter. The highest increasing of WUE in 14 days irrigation interval was 44.08 (gr/m3) in comparison with non-irrigation treatment.

Because of wide and unique view in satellite data, that inculdes most parts of electeromagnetic spectrum, and their update images they are suitable for producting Landuse map. This research was done for introduction the most important methods of Landuse map producing by using of landsat and IRS digital data in Dasht-e-Qom (with 183,853 hectares area). Landsat and IRS include ETM+ and PAN & Liss III sensors respectively. After nessesary corrections and preprossecing of images, they were classified with four different methods. In classification by using the vegetative indices, PVI indice showed the highest accuracy (with 40.8% overall accuracy and 0.29 Kappa coefficient).In one-band supervised classification, the highest accuracy is band1 of ETM+ (with 17.41% overall accuracy and 0.004 kappa coefficient).in this classification, density slicing method has been used. The results showed that using the vegetation indices and one-band supervised classifications can ,t use for a perfect and independent images classification, because it mixes spectral phenomena and is limited to recognization a few ranges of classes. In the multispectral supervised classification, the highest accuracy related to ETM+ data and maximum likelihood (with 71.95% of overall accuracy and 0.67 kappa coefficient). The hybrid method is the most highest accurant and the best of 4 classification methods (with 76.42% overall accuracy and 0.72 kappa coefficient).

The aim of this research was to study the relationships between presence of plant species and environmental factors in Poshtkoh rangelands of Yazd province. After delimitation of the study area, sampling was performed using randomized-systematic method. Accordingly, vegetation data including presence, density and cover percentage were determined in each plot. The topographic conditions were recorded in plot locations. Soil samples were taken at depths of 0-30 and 30-60 cm in each plot. The measured soil variables included texture, lime, saturation moisture, gypsum, acidity (pH), ECe and SAR. Logistic regression technique was used to analyze the collected data. The results showed that the vegetation distribution is mainly related to soil characteristics such as EC, saturation moisture, gypsum, gravel and lime. The presence of A. sieberi has inverse relation with EC. D. ammoniacum has also negative relation with saturation moisture, gravel and lime. While, the presence of Ep.st-Zy.eu has positive relation with gypsum.

The objective of this study was to assess the relationship between vegetation, landform and physicochemical properties of soil. At the first terrain map unit were provided using the landsat thematic mapper (TM) satellite images, aerial photograph, topographical and geology map. Field sampling was done in the representative area using plot sampling. 104 plots 100 m2 were sampled in each plot landform parameters (slope, elevation, aspect), percentage of vegetation cover, were measured and stoniness and browsing damage were estimated and one soil sample was taken for measuring EC, pH, and texture. Relationship between vegetation and environmental factors was based on correlation analysis, box plot and Kruskal Wallis test (multiple comparison). Correlation analysis showed a positive correlation between vegetation cover with slope and elevation and a negative correlation with EC. Based on the Kruskal Wallis test there was significant difference in vegetation cover between different geopedological map units. No significant relationships were found between vegetation cover and other soil properties such as pH and texture.

Seidlitzia rosmarinus (Chenopodiaceae), a permanent wooden plant, expands in marsh margins including soil and water salinity. The plant is somehow used in food of camel. It is a resistance plant to salinity in dry land and salt desert margins, which plays an important role in preservation and keeping soil. In this research, the effects of several saline solutions (NaCl, NaNO3, KCl, and KNO3) with five different concentrations, 100, 200, 300 and 400 mM and osmotic stress using polyethylenglygol (isosmotic with salt solutions)on the rate and percentage of seed germination, growth, length, dry weight, fresh weight and proline content were investigated. Results showed that, increasing in salinity decreased all above measurements. The seeds germinated in NaCl, KCl and KNO3 to 400 mM whereas NaNO3 with more than 100 mM inhibited germination. Proline content was increased with enhance NaCl concentration. Increasing in osmotic pressure alone could not affect on above mentioned parameters.

Drought is one of the natural disasters that create some of damaging impacts to ecological environments. The Average annual and monthly rainfall of limited projects stations were surveyed in statistical periods 30 years (1970-1999) to analyze droughts of south and south– east of our country. At first the average annual rainfall was estimated in a drought period according to statistical rules and best-selected distribution. Then the map of chosen area was provided based on the estimated rain fall rate to average annual of each station for return period (P/Pmean) Due to provided maps may recognize when drought with a T return period occurs in whole area and then which area has more critical weakness. ofcourse, each area would have more critical condition that have weakness with more diversity to their mean long time weaknesses. Using dimensionless statistical series criteria may evaluate drought area with similar T return period intensity.

Drought is the most harmful climatic event whose impacts are more important in regional scale. Thus, the aim of this study is to introduce a method for drought regional analysis. In this study, rainfall trend analysis by Mann-Kendal test and homogeneity test by run test were investigated and showed rainfall homogeneity and no significant rainfall trend. Then, using two important deciles and standardized precipitation indices of 8 stations in the region, drought condition for selected stations and period were compared and its results were investigated for the region. The results showed that drought cover 60 percent of the area averagely. The study also showed that rainfall deciles have relationship with longitude only. In other words, drought occurs more frequently and with higher intensities eastward.

With regards to snow importance it is necessary to predict the runoff for optimum use of the water. For this, snow cover area estimation of catchments and their variation during the year is necessary, that satellite images make available the necessary information desirably. In this study snow cover area extracted as the most important hydrological variation by using NOAA AVHRR images. Then the SRM model (Snowmelt Runoff Modelling) is used for runoff computation. The model computes the snowmelt runoff by using meteorology and hydrology parameters and physical characteristics of the catchment and shows the result as graph and numerically accompanied with measured runoff. In this study all mentioned data and parameters (daily) were entered the SRM model for the year (1996-97) that the model by analyzing them computed the runoff and produced it as graph and numerically accompanied with measured runoff. The model accuracy evaluated by comparison of two computed and measured runoff that the simulation was successful that the coeffcient of determination (R2) and volume difference (Dv) are 0.81 and 2.75%. the results shows the high accuracy of the model in computing snowmelt runoff for the study area that shows the capability of the model for the other catchments of the region.

In order to study the amount of transpiration in rangeland species of Agropyron elengutum and Bromus inermis, seeds of these species were planted in five replications in small vases with the upper area of 50.27 cm2 and under a relatively natural condition and adjacent to five control vases. The study was conducted in College of Natural Resources and Marine Sciences at Tarbait Modares University. The transpiration rates were then determined by weighting method considering the amount of water used for irrigation and evaporated from plant-free vases for 33 days during Spring 2004. The weight of these vases was measured by 0.0001 accuracy balance. The diurnal changes of transpiration in above species, their statistical differences and evaluation of effects of humidity and air temperature on transpiration were respectively analyzed by Excel software, ANOVA, Dunkan test and regression method in SPSS software package. The results of the study confirmed differences in transpiration rates during this period and significant difference was also achieved among species in number of plants and dry matter as well. The most and the least amount of transpiration was also recorded for Agropyron intermedium and Bromus inermis at the rate of 59.79 and 31.22 milliliter per gram dry matter which clearly verified the minimum and the maximum water efficiency at 1% level of significance, respectively. The results of regression analysis also indicated the linear relationship between transpiration and humidity concerning the mentioned species and under study region.

In order to investigtion of woody plants biodiversity in different soils in two managed plant associations in Namkhaneh district of Kheyrudkenar Educational and Research Forest Sixty sample plots with 1000m2 Surface and 200´200m network were selected systematic elective in 125 hectres of each plant association and 250 hectares totally. In each sample 5 micro plots with 45m2 surface was elected. The results showed that the number of seedling in hectare in fagetum association is more than in carpino-fagetum association totally. With due attention to different beech seedling cycle in two association, the number of seedling in them are different. The number of Fagus orientalis and Caripnus betulus seedling in carpino-fagetum association is more than fagetum association, but the number of Acer velutium seedling is more in fagetum association is more than carpino-fagetum association. The number of Ulmus glabra, Tilia begonifolia, Acer cappadosicum, Quercus castaneifolia in fagetum association and carpino-fagetum association showed statistical significant difference. The natural structure of mass and reproduction style have been preserved during two period of exploitation by selective culting method.