IRANIAN JOURNAL OF RANGE AND DESERT RESEARCH
Year:2003 | Volume:10 | Issue:2|Papers Count:7

Dameghan floodwater spreading system in Semnan province is located on Daryan temporary river Ghoosheh plain. The system was established in 1992 by local organization of Ministry of Jahade – Keshavarzi in sake of soil conservation and as a consequence strengthening of water tables. The system has 12 channels of 350 m width and 2 km length. The effect of flood water spreading on soil fertility was examined in this study. Three primary stripes were selected, and each divided in to 12 equal parts. Soil samples were collected from 0-15, 15-30 and 30-45 cm depths. Control site were selected from the strips adjacent areas. Soil samples were taken to the lab and analyzed. Analysis of variation showed that the effect of floodwater spreading on increasing of silt, organic matter(Om), saturation percent(Sp), chlorine(Cl) Nitrogen(N) and phosphorous(P) at probability of %99 is significant while on increasing of clay, electrical conductivity(EC), soil cations (Ca++), (Mg++), (Na+) and (K+) at probability of %95. The negative effect of flood water spreading on sand and (pH) at probability of %99 significant. No significant effect on calcium carbonate (Caco3), capacity of cation exchange (CEC), percent of exchangeable sodium(ESP) and absorbing potassium (K) was observed.

In order to survey and assess range management designs affect on the rangeland improvement in the west Azerbaijan province, the sarhalan and kozerash range lands of Sam city respectively 15 and 60 selected.For information collection utilizer research, interview, observation and field study were used by using of question nairire and interview with Utilizer and natural resources managers, advantages and defects of range management design determined, by observation and field study the following parameters such as range condition, range trend, Range capacity and production studied and compared between two communal boundaries the using T-test and descriptive such as frequency and percentage and other information analyzed. the result of data showed.1- there is a significant relationship between the range land condition on range management design and common used rangeland.2- there is a significant relationship between the range land production on range management design and common used rangeland.3- there is a significant relationship between the range land capacity on on range management design and common used rangeland.

In order to study of the relationships between plant cover and geomorphological units, the barron area located in North Western of Iran (west Azarbaijan province) 4.5 km, the North of C?halderan city between 39o 6' 21’ to 39o 14' 3’ North latitude and 44o 29' 28’ to 44o 20' 20’ east longitude was selected. Considering that the recognition of the ecological resources have the important role in land evaluation at first the Climatology, physiography, Geology and geomorphology were studied, then the maps of the slope, aspect, hypsometry and geomorphology combined with each other to obtain work units. in each work unit the sampling of vegetation were done. According to lithology map a number of 3units, 7 types 19 geomorphological faces and 48 vegetation units were recognized. The result showed that there is a relationship between plant communities and geomorphological units in the mountains. In this study Astragalus (Stenonychium) parrowianus Boiss et Haussk was introduced as the key species of colourd melange formation

The effect of phosphorus fertilizer and seed rates were examined on herbage production of sainfoin cultivar namely, Shahrekordi. Study was conducted at Homand research station with clay- loam texture soils for 6 years in 1993-1998. Split plot design with 4 replications were used in this Experiment. The main plots were P205 with five levels of 0- 30 -45 - 60 and 75 kg/ha, and sub plots were seed rates wi~ four levels of 15- 25-35-45 kg/ha.Dry matter production, plant density, Plant height and plant mortality of sainfoin were measured each year in growing season. Collected data were analyzed each year and finally for six years.Dry matter production varied each year, due to different environmental conditions. Fertilizer and seed rate treatments influenced dry matter production in some years of Study period. The combined effects of seed and fertilizer treatments increased dry matter production. The treatments of seed (45Kg/ha) +phosphorus (75Kg/ha) and seed rate (15Kg/ha) +phosphorus (60Kg/ha) were the best, with 1143.2 and 1135.6 kg/ha dry matter production. The treatment of seed rate (45Kg/ha) +control (0kg/ha phosphorus fertilizer) with 882.4 kg/ha produced the lowest amount of forage yield, overall results showed that the effect of treatments were not significant on plant density and plant heights in 1995 and 1998, but the seed rates affected these factors in 1996-97.

Geomorphology is one of the basic elements of Natural resources studies. Biophysical characteristics of Miankale, located between Behshahr and Neka in Mazandaran province, is studied seeking significance of the relation between geomorphological units and vegetation composition. Using Broun-Blanguet and KÜchler methods’ 1:50000 topographic map, 1:20000 Arial photos and 1:250000 geological map, different environmental parameters for all geomorphological units were determined. As a result 67 plant species on 31 vegetation units were distinguished. On the basis of climate, geomorphology, vegetation, soil and hydrology a geobotanical map was prepared. Results of this study suggest that geomorphology is a suitable basis for evaluation of environmental parameters.

The effects of rotational and continuous grazing systems and light, medium and heavy grazing intensities on the forage quality (raw protein, raw fiber and N-free extraction) of Bromus tomentellus were Studied 8 times of growing season in Homand-e-abesard rangeland research station in 2001. The forage qualities were determined by AOAC methods and analyzed by a random block design in each system separately. The effects of two grazing systems on the forage quality were compared by t-test and the means of three grazing intensities were compared by Dancans test. The results showed that protein and N-free extraction were increased while the grazing intensities were decreased but the fiber decreased and there were no significant differences between treatments on the protein and also fiber in each system. The N-free extraction in rotational system was more than the continuous under all intensity treatments and differed significantly (p=0.026).