نشریه پژوهش های آبخیزداری
پیاپی 101 (زمستان 1392)

Acknowledgeofplantnutritivevaluehelpsrancherstocreateabalancebetweenavailablenutrien andanimalnutritiverequirementsandhencetheycanmaximizelivestockperformance. Sampleswastakenfromninerangespecies (include: Festucarubra, Aeluropuslittoralis, Alopecurustextilis, Tanacetumpolycephalum, Medicagosativa, Halothamnusglaucus, Salsolatomentosa, HalocnemumstrobilaceumandHammadaSalicornica) inthreephenologicalstagesandtwositeswiththreereplicationsforeachspecies. Todochemicalanalysis, thesamplesweredryingandgroundandthennitrogen (N), aciddetergentfiber (ADF) andelementssuchasphosphorousandcalciumwasmeasured. Experimentalformulawasusedtoestimatecrudeprotein (CP) drymatterdigestibility (DMD) andmetabolizableenergy (ME). ANOVA, univariateandDuncan’stestwereusedtoanalyzethedata. Theresultsindicatedthattheeffectiveindicesofnutritivevaluehadconsiderablechangesinpheno ogicalstagesandithadsignificantinfluenceonforagenutritivevalue. Withadvancinggrowthstagestheamountofcrudeprotein (CP), draymaterdigestibility (DMD) andmetabolizableenergy (ME) decreaseandamountofaciddetergentfiber (ADF) increases. Theresultsofmineralelementsindicatedthatamountofphosphorousinherbaceousplantsexcep forFestucarubradecreasedandamountofcalciumexceptforFestucarubraincreasedbyadvancin thegrowthstagesbutitcouldnotfoundanytrendinshrubplants.

Seed dormancy is a condition that despite living in favorable conditions, the seed does not germinate. Thus, dormancy represents a seed’s fastidiousness about the germination conditions it requires. Seed priming is a physiological technique that improves seed performance including faster and more synchronized germination times. The seeds of Astragalusgossypinus and Zygophyllumeurypterum have germination problems due to having hard and impermeable testa. Therefore, because of importance of this two species in rangelands, this study conducted for determination of best priming methods and help to seeds germination. This experiment was done on the base of Completely Randomized Design in 4 priming treatments and 4 repetitions. The treatments of this experiment were as: control treatment (distilled water), KNO3 [0.2%], H2SO4 [98%], and GA3 [300 ppm]. Then, germination percentage, germination velocity, we weight, dry weight, root length and shoot length was measured. Data analysis was done by SPSS software using ANOVA and Duncan test. The results showed that H2SO4 had more effect on Astragalusgossypinus seeds germination. Likewise, GA3 and KNO3 improved germination of this species, respectively. In Zygophyllumeurypterum the results revealed that H2SO4 not only didn’t increase the germination, but also damaged the embryo. Moreover, GA3 and KNO3 had same effect on improved of its germination.

Decreasing the number of climatic variables affecting evapotranspiration using sensitivity analysis and identifying their relative importance has a large role in water resources management and crop water requirements, especially in areas with no or low climatic data. The FAO Penman-Monteith (FAO P-M) is a widely accepted method for estimating reference crop evapotranspiartion (ET0). In this research, three approaches of artificial neural network, linear regression and factor analysis were used to identify the most sensitive parameters affecting (ET0) based on the FAO P-M method. For this purpose, the appropriate data including monthly mean, minimum and maximum temperature and relative humidity, daily sunshine, wind speed, saturation and actual vapor pressure, saturation vapor pressure, slope vapor pressure, psychometric constant, net radiation and etc. were provided for a 50-year recorded data length (1956-2005) at four main synoptic stations of Yazd, Kerman, Shiraz and Isfahan in central Iran. Then, simple local and regional equations were obtained using the main parameters identified by using the three methods mentioned above. The results of these approaches were compared using coefficient of determination (R2) and RMSE statistics. The results showed some differences between the outputs of these three methods, but there are certain factors located in high priorities of the three methods. Meanwhile mean monthly temperature was identified as the most important climatic factor influencing on reference evapotranspiration. Then, to estimate ET0, local equations were proposed using the main identified climatic parameters. As an overall result, simple equations with appropriate accuracy can be derived to estimate ET0 using low available climatic data in a regional analysis procedure.

Observation of watershed management, abilities and limitations assessment (such as landslides) of natural resources. The other side, landuse planning and stable development strategy, solidate spreadly with lawly and techniqual obligations by capability assessment maps and density and type invironment hazard zonation such as landslides and land unstability. This research was effort in this regard, studing landslides trigerring factors and mass movement hazard zoning for the Zonouz chay watershed, zoned by both Multiple linear regression (MR) and Analytical Hierarchy process (AHP) methods. For this idea first the landslides triggering factores of the area were studied, then the most important factors including lotology, slop, distance of road, distance of fual, altitude, aspect, texture of soil landuse were investigated and next, the map of landslides distribution was prepared. In linear MR merhod, after changing landslides distribution map to 250m×250m squar unit density area map, was given weight quality map of factors by density area model and was maked their quatitative statement s. Employing Stepwise regression method and the zoning model was found after omitting the altitude and landuse factors. In AHP method, the above mentioned 8 factors were used. Next, quantify the factors and indexes weights by composition with density area model. Then, gave them weights and zoning model was found. Assessment accuracy between two Multipl linear regession and Analytical Hierarchy process methods has done by Qualitative Summary index (QS). Finally, the results of these two methods, it was found that the AHP method, with composition density area model with QS = 1.1, is accurate than Multiple linear Regression (MR) method.

The aim of this study was to evaluate the most important environmental factor affecting changes species diversity in rangelands of Bijar protected region. Sampling in each plant type that was determined from field method was done along four 300 meter transects. 15 plots (1m2) established along each transect in 20 meter distances. The kind and the amount of existing species and the percentage of vegetation cover were determined in each plot. Also were taken soil samples from beginning and end of each transect from 0-20 and 20-100 cm depth. Measurement environmental factors in this study were included: soil texture (clay, silt, sand), gravel percentage, slope, aspect, altitude, organic material, EC, pH and lime. Species diversity in each type with counting total species as species richness were considered. Simpson and Shanon-Winer index as heterogeneous index and also Simpson, Kamargo and Smith-Wilson indices were considered as homogenous indices. Above mentioned case calculated using from Ecological Methodology. After collecting data, the Principal Component Analysis (PCA) was used to determine environmental factors affecting on changes of species diversity. The results showed that Ac. millefolium-S.barbata and D.mucronata-Th.kotschyanus types have the highest and lowest species diversity respectively. The obtained results of this study was showed that among studied factors, texture include clay, silt and sand percentage gravel, lime; altitude and slope had the most influence on changes of species diversity in studied region.Results from this study can be used to manage, restore and improve vegetation in areas with similar environmental conditions.

Pasture is one of the most important and most valuable national resources. Obviously, the utilization of the pasture that it is associated with preservation and sustainability requires efficient planning and management. In this regard, the objective of present research was identification of temporal changes in the production, harvesting and regrowth of plants in different treatments and differences with the production control rate during 3 years. To achieve this goal, the study of effect the grazing intensities on forage production and vitality of Artemisiasieberi performed in Meime Soh location from 2006 to 2010. Treatments in each block include four grazing intensities of 25, 50, 75% and control (no harvest). In each treatment 10 basis of each species were used as replicates. The results analyzed by split plots in time with completely randomize design with ten replicates and three years by SAS software. Generally, the results showed that the highest production is appeared in grazing intensity control. Also, the effect of total production and plant vigor in Artemisiasieberi were significant. The harvest intensity is recommended 25-50% so that causes the stability of this specie, regard to the natural habitat features of this specie and also conditions and the behavior of its vegetative.

Asafoetida is one of the valuable medicinal plants belonging of the Apiaceae family. Resin extracted from this plant has many uses in industry and pharmacy. Because unsustainable harvesting of pastures, this plant has medicinal value at risk of extinction. Asafoetida seedlings in the early of the life cycle, have slow growth led to the poor seedlings establishment.Osmopriming improvement of techniques that can improve seed germination and seedling growth and thus to improve its establishment. To examine the effects of seed osmopriming on improving asafetida germination and seedling growth, carried out a factorial experiment in completely randomized design with three factors: time of osmopriming in three levels 12, 24 and 36 hours, solution type with three levels of calcium chloride, potassium dihydrogen phosphate and polyethylene glycol and osmotic potential -0.5, -1.0, -1.5 and -2.0 Mpa with 3 replications in the Faculty of Agriculture of Birjand University. The results indicated that time of osmopriming had significant effect on asafetida seed germination and seedling growth and the best time to asafetida seed osmopriming was 12 hours. The effect of solution type on seed germination and seedling growth was significant and that the solution of calcium chloride and potassium dihydrogen phosphate were treated showed a better seed germination and seedling growth. But osmotic potential effects on any of the germination and seedling growthwere significant

Performance of hydrological models are used in a variety of issues of real time flood forecasting to design water structures and policies to prevent from the effects of extreme hydrological events (floods and droughts), they depend on how they are calibrated. In these models, the values of some parameters can be estimated with observation and direct measure. But some others are not directly observable and their estimation is done by indirect techniques of model fitting in historical data. Purpose of this study is Investigating and calibration hydrological parameters of Soil Moisture Accounting model (HMS SMA) for estimating runoff in the time scale monthly. Results confirmed the ability to HMS SMA Model in predicting discharge and simulate process rainfall-runoff on a monthly time scale.

One of the important applications of satellite remote sensing technology is mapping and monitoring changes over time. The aim of this study was to detect the vegetation condition of the Sarigol protected area in Esfarayen region of Northern Khorasan province using Landsat-MSS, TM and ETM+ images over 36 years. After applying geometric and radiometric corrections, the map of vegetation cover and its changes was achieved via different image analysis techniques and the post-classification method. Finally, modeling techniques were used to forecast the vegetation status of the Sarigol for the year 2025. Results showed a significant increase in shrub vegetation cover about 76000 hectares during the 36 years from 1973 to 2009. The results of vegetation modeling also showed that vegetation cover will continue to increase in 2025 due to the rehabilitation of rangelands and bare lands (kappa= 0.80 and overall accuracy= 0.75 and 91/83). According to the results, it can be said that the technology of remote sensing can be used as an effective tool for monitoring and analyzing vegetation cover in protected areas and also it can provide clear evidence for management related differences in vegetation cover.

One of the effects and consequences of air pollution is acidic rain phenomenon. In the past two decades in some industrial areas and factories on the activities of sulfur dioxide and nitrogen dioxide in air has increased. These two materials in the atmosphere with oxygen and water vapor create a chemical reaction and to nitric and sulfuric acid are converted. In this study, in order to investigate the sensitivity of erosion and sediment yield of Aghajari Formation to acidic rainfall, parts of Margha watershed area in Izeh Township are selected with the area of 1609 hectare. This investigation in order to determine productivity runoff and sediment in 8 points and with 3 replicates in aghajari formation in different intensities 1, 1/25 mm in min and in the intensities of distilled water and 4, 5 acidic water in four aspects of northern, southern, eastern, western with using kamphorst rain simulator was done. In order to analyze statistical was used SPSS and EXCEL packages. The highest of runoff and sediment rates in aghajari formation in 1, 1/25 mm in min are related to 4 acidic rainfalls. The rainfall of 5 acidic also runoff and sediment is more than the rain of distilled water. The rates changes in infiltration and threshold runoff in rainfall different intensities also showed significant difference.

Zygophyllumatriplicoides is one of the most important species rang lands of country. A desert shrub that can tolerate long term droughts. This feather is going to studied climate specification of Zygophyllumatriplicoides habitats in Isfahan province. So the numbers of 68 climate variables that have more important is aspect of the ecological conditions selected and the method of factor analysis, factors that influence the distribution of species studied. Using factor analysis, four factor, the cooling temperature, precipitation, cloudy and wind were determined. It is allocated 34.45, 29.43, 11.79 and 9.06 the percent of variance variable sequential, that repeat 84.74 percent of changes totally. Average of factor scores and climate variables are determined in three types of Zygophyllumatriplicoides as dominant specie, Zygophyllum specie as following specie and zones of Zygophyllum free, and finally the impact of factors and climate primary variables on Zygophyllumatriplicoides types are determinate. Besides climate factors, effect of height from sea level in distribution of specie is analyzed. The results show that temperature factor was most important of effective climate factor on specie distribution in Isfahan province and then precipitation factor affects distribution of specie. Also it cannot ignore the effect of height from sea level on Zygophyllum types of analyze.

Desertification refers to land degradation phenomenon in arid, semi-arid and dry sub-humid areas, resulting from various factors including climate variation and human activities. For evaluation and mapping of desertification many research have been conducted leading to regional and local models. In this research, among different existing methods IMDPA was selected and desertification intensity was evaluated on the basis of 2 criteria and 8 indices including: soil (soil depth, Electrical Conductivity, texture and gravel percentage) and climate (precipitation, aridity index and drought index). Each criterion was assessed based on the selected indices which result in qualitative mapping of each criterion cased on geometric average of the indices. Finally, sensitive map of region was extracted using geometric average of all criteria. Thematic databases, with a 1:50000 scale resolution, were integrated and elaborated in a GIS based on ArcGIS. Analysis of desertification criteria in Aminabad region showed that among study criteria, climate criterion is a major problem in the study area with a geometric average of 2.3 which shows medium class while soil criterion with a weighted average of 1.28 stands in low class of desertification. Also 17.98 ha of area (14.5 %) was categorized in low class of desertification, 75.02ha (60.5%) and 6.2ha (5%) of the area have high and very high class of desertification, respectively.

In this research, the reactions of the Seidlitziarosmarinus species to the fluctuation of precipitation and ground water table were studied at Siah-kuh in Ardakan-Yazd. For this purpose, plant parameters of Seidlitziarosmarinus were monitored every yearalong four permanent lines transect in 60 plots (2 m2). Every year, Water table measured in three pisometric wells and Meteorological data were collected from nearby climatological station.Regarding the amount of collecting data after nine years, Groundwater depth varied from 12.5 to 19.71 m and the entire region experienced two drought years (2001 and 2005) throughout the study years.Vegetation response to groundwater and precipitation fluctuation analyzed by correlation and regression analysis. The regression results show that canopy cover and the density of the Seidlitziarosmarinus species in the region are highly influenced by the water table depth (R2=0.97 and R2=0.9 respectively). By using stepwise regression, an equation between the amount of yield and annual precipitation was obtained with a high correlation coefficient (R2=0.8). Thus, Increase in water table depth in the coming years will has more ecological consequences for Seidlitziarosmarinus plant communities. Finally, it led to bioenvironmental deterioration such as land desertification in Siah-kooh, Ardakan. To avoid land desertification in this area, optimization of groundwater usage in agricultur and industry in Yazd-Ardakan plain is very important.

Today ground water has an important role for preparing drinking uses in most parts of the world. Increased population and thereby increased utilization of these resources has resulted to decreasing not only quantity but also quality of these resources. The main propose of this study is investigation of the trends of temporal and spatial variation in water quality in shahr-e-Babak to prevent issues and problems due to consumption of contaminated water by identifying contaminated parts of the region in this study parameters Ca, Cl, Mg, Na, So4 and pH were used and zoning of qualitative data was conducted using kringing method via Arc GIS 9.3, kriging method has the lowest error compared to IDW in the viewpoint of RMSE and ME. Then water of the region was classified for drinking uses based on shuller classification. Results obtained from this research showed that based on shuller diagram, water of the region in 2002 had the appropriate quality for all of elements except Mg, and in 2009 for all of element except C1 had the appropriate quality in the viewpoint of drinking uses, but general trend of the water quality is decreasing and north to east part of the region is the best part for providing water for drinking.

This study investigates the impact of cattle grazing intensity at long-term (LT, 2.7 AU/ha/y for 33 years) and short-term heavy (ST, 5 AU/ha/y for 2 years) on the heavy metal concentrations in soils of tropical pastures, Malaysia. Soil samples were collected at randomly selected points at 0-10 and 10-20 cm depth in both grazed and ungrazed treatments. The concentration of heavy metals (Cd, Fe, Mn, Cu, Cr, Pb, and Zn) was measured by inductively coupled plasma (ICP) spectrophotometry. The heavy metal concentrations in the soil were not affected by ST grazing intensity. The concentrations of Fe, Mn and Zn were significantly affected (P £ 0.05) by LT grazing intensity. The concentrations of Fe, Mn, Cu and Zn in LT grazed pasture soil were 127.9, 194.8, 54.8 and 39900% higher, respectively, than ungrazed pasture. Soil Fe, Mn and Zn concentrations were significantly higher (P < 0.05) in surface (0-10 cm) than subsurface (10-20 cm) soils. Results suggest that the excreta of grazing cattle can be an important source of heavy metals in intensively managed pastures in the long-term. However, metal concentrations were maintained below the maximum standard limits and were not high enough to be dangerous from the toxicological point of view.

The ability of rangeland hillslope to runoff production is contributed to two key factors including surface geometric and vegetation cover composition Different models was developed for simulating runoff production based on geometric and physical and vegetation properties that can estimate runoff production. This research was conducted to evaluate the ability of hillsope version of process based WEPP model in prediction of runoff production dynamic in different slope angle (25, 35 and 45 %) and different rangeland type. Runoff collection plots were established in Kabode area in Gharasoo watershed with 3×10 meter dimension in three replications and in three rangeland type. Climatic data including rainfall and temperature was recorded on site and the others including wind velocity and direction, solar radiation and dew points prepared in Kermanshah synoptic climate station. Runoff simulation was done as single storm using v2008.9 version of WEPP model. Results indicated that maximum prediction accuracy was made in 45% sloe. The model estimation error was as underestimation and the nonlinear relationship was existed between predicted and measured data. Model has good advantages in simulation the land cover type and management condition effects on production of runoff and water harvesting.