NATURAL ECOSYSTEMS OF IRAN
Year:2012 | Volume:2 | Issue:2|Papers Count:9

To achieve in Zagros forestry plans, considering all aspect of sustainable forest management strategies, socio-economic and antithetical issues are required. In this paper Analytic Network Process (ANP), as a sound approach to assessment multi-dimensional and contradictory problems, is described, and employed to study suitable forest territorial organization in the Zagros. In ANP process, firstly, the effective indicators and criteria are included in the BOCR model. The importance of each indicator and criterion is then calculated using Super Decision software. Evaluation and prioritization of the alternatives (in our case: watershed, village conventional territory and family conventional territory) are performed according to the results. The final step is to perform sensitivity analysis on the final outcome and interpret the results. The decision framework proposed by ANP offers a means for final decision-makings.

Water Infiltration into the soil accounts as one of the processes that is considered by most of researchers moreover it has an important role in the water cycle. Due to the importance of infiltration phenomenon, scientists are continuously endeavoring to find an appropriate model for quantifying the infiltration rate. In the recent years, developing the simulation models related to the soil has been being increased. Also these models have been developed for evaluating of the problems concerned to environment and agriculture. The present study has been programmed for identifying the best infiltration models for two land uses including rangelands and woodlands in Davood Rashid watershed located in Lorestan province. In this research, Measuring of infiltration rate was done by double rings methods and some infiltration models including Kostiacove, Philip, Horton, Soil Conservation Service (SCS) and Green Ampt were considered for estimating of infiltration rate. Results showed that all of the infiltration characteristics comprised of accumulated infiltration, ultimate infiltration rate, and average of infiltration rate, time to fixed infiltration rate and the slope of infiltration rate in the rangelands were less than woodland land use. In addition, the best models for simulating of infiltration in rangeland and woodland land uses have been chosen SCS and Philip models with coefficients of descriptive 0.967 and 0.993 respectively. Also, coefficients of efficiency relevant to two mentioned models were higher than other models and Horton model was selected as the weakest model in two investigated land uses of rangeland and woodland.

This study was conducted to evaluate the response of Acer cineracens Boiss seeds under accelerated aging test. The accelerated aging test was carried out at three different temperatures: 41, 43 and 45°C with four duration periods of 48, 72, 96, 144 and a relative humidity of 100%. The seeds were subjected to tests of their quality including standard germination, vigor index and growth of seedling. A completely randomized factorial design with four replications was used. Results indicated that Seeds had a reduction of viability and vigor after accelerated aging at 41°C for 96 hours, 43 and 45°C for 72-144 hours. Germination, vigor index and growth of seedling showed a greater response to accelerated aging.

Management of soil erosion and sedimentation require planning and decision making Because of their importance. Knowledge on erosion rates and sediment production condtion is necessary for identification of critical areas and prioritize them as watershed management issues. The status of erosion in the Lorestan province was cheked through implementing EPM model and using RS and GIS. Some themathic layers such as, land units, Geology sensitivity, land use, work units were perpared. Land use type, intensity and erosion forms were determined in work units Through Field visit. Sensitivity coefficient of rock and soil, slope, mean annual average temperature and precipitation were extracted. Based on the model instruction, erosion coefficient map (Z) and the specific erosion (Wsp) were prepared. The layer classification and map erosion severity classes were obtained and compared within sub base map layers and the relationship were examined. The results show that the average erosion coefficient is 0.58, the average rate of erosion 13.9 tons per hectare and 54.5 percent of province assigned to high class of erosion. The main priority areas for planning natural resources and soil conservation located in the South and South-West of province where appropriate conditions are now located in the East part of Province.

The amount of rainfall reaching the forest floor after passing through the canopy is an important fraction of the water balance in forest ecosystems. This study was carried out in order to investigate the effect of rainfall event size on rainfall interception of Persian oak trees (Quercus brantii var. persica). Sixteen throughfall manual gauges were placed beneath the five selected tree canopies in the eight geographic directions and the gross rainfall (GR) was measured by the mean of six homemade gauges records placed in an open area adjacent to the study site. Rainfall interception (I) was indirectly estimated as the difference between GR and TF. The measurements were recorded from April to December 2010. During this period, 9 rainfall events with cumulative depth of 157.3 mm was collected and average cumulative rainfall interception of Persian oak trees estimated to 47.4 mm or 35.8% of total rainfall. Significant negative logarithmic relationship (r2= 0.808) were found between I:GR and GR. The results showed that with increasing rainfall depth, ratio between I and I:GR was decreased.

In this research in order to investigate site demand of manna Oak trees (Quercusbrantii), after gathering some basic data, dispersion limits of this species in Kermanshah province were identified. Then these areas were classified to altitude rages (>1500, 1500-2000, <2000m), four cardinal points (northern, southern, western, eastern) and different land forms (valley, crestline, foothill, flat). To gather requisite information, some 500m2 plots were established in each mentioned situation at least with three replications. In each plot some variables such as: number of trees, diameter at breast height (DBH) for seed tress or collar diameter of biggest sprout for coppice trees, total height, stem length and two perpendicular diameters of crown for the mentioned species were recorded. Furthermore regenerations were tallied in 100 m2 subplots in the center of each plot. In order to study soil, one profile were allocated in each plot and described. Then some samples were taken to determine some chemical and physical characteristics such as: Soil texture, C, pH, Ec, Caco3 in laboratory.Resuits Showed that for species Manna Oak, crestline Form with west aspect prepared the best position. Also Principle Component Analysis (PCA) of soil in oak Manna provenances showed that physics elements at surface layer and chemical elements at substrate are effective to improve vegetative paraweters of manna Oak.

The aim of this study was the evaluation of the potential of ecotourism for Badreh area by using of GIS. The evaluation was done in three steps. At the first step, using of Analytical Hierarchy Process (AHP) the most important effective criteria and sub criteria in the potential evaluation of ecotourism for the study area were determined. Then, with respect to experts opinions the criteria and sub criteria were weighted. At the second step, using of GIS, the geographical maps of related to each one of the effective criteria in the evaluation were provided. In the last phase, each one of these maps was combined with its corresponding weights in the GIS environment and the final map of the potential of ecotourism for the study area was provided. The results showed that about 8.48% of the region fall into class 1 and 16.5 percent of the study area belong to the class 2 in terms of the potential for the ecotourism respectively. This result shows a suitable potential of these areas for the ecotourism development. In addition, the results show that 52.43 and 22.59 percent of the region fall into 3 and 4 classes respectively.

The visual impact is most obvious impact of development projects (urban development, roads, piping, gas, oil, water, electricity and Telephone, Web mining and industry) that they will have on the face of nature while usually in such projects has been less attention to it Therefore, We will discuss this issue further in this article And presenting a case study, a rapid method for evaluating such projects were presented. In this paper, first, the research literature and the different methods of the visual evaluation will be presented. Then a combined approach using geographic information systems software capabilities (GIS) has been used in here. Case study is done on local quarries (Chegeni Region in Khorramabad), but techniques are generalizable to other projects.

Afforestations can have major effects on soil physicochemical properties by the time passes. In order to compare afforestation effects by exotic needle leaves and broad leaves trees on soil physicochemical properties in Gahar forest park, Dorood, three afforested type (black locust stand, Turkish red pine stand, and mixed stand of Turkish red pine and black locust) and a natural Iranian Oak stand were selected. At the same landforms in each afforested types and natural Iranian Oak stand, three compound soil samples, which each one is composed of four profiles from three horizons 0-10, 10-20, and 20-30, were sampled. Results show that in comparison of afforested types and natural Iranian Oak stand, soil physicochemical properties were affected by kind of planted trees. In Turkish red pine stand values of P, EC, and silt were increased while values of organic C, N, and pH were decreased. Also black locust plantation was result to increase in N, organic C, and P. From the results it is implied that after 36 years, afforestation can have explicit effects on soil physicochemical properties along to changes in plant and biotic communities.