IRANIAN JOURNAL OF RANGE AND DESERT RESEARCH
Year:2001 | Volume:- | Issue:3|Papers Count:6

Six cultivars of alfalfa (Hamadani, Ghareh- Yonjeh, kerisari, Simerchenskaya codi and Maopa) were compared in a randornized complete bock design with four replication in rain-fed areas of Zagheh and Ghaed Rahmat north-east of Khoramabad in Lorestan Province for 5 years. The mean annual precipitation of Zagheh and Ghaed Rahmat are 603.5 and 575.4mm. The experiment was established in the spring of 1985. Dry fodder per hectar, plant height, canopy cover, diameter, distribution and vigourity were recorded. Results show that there was not significant difference between dry matter and height of cultivars in level of 5%. Means compared with Duncan's new multiple range tests. Kerisari and Simerchenskaya coltivars with a production of 2217 and 2058 kg/ha highest forage production in Zaghe and Kerisari and Codi coltivars with 1321 and 1275 kg/ha showed highest production in Ghaed Rahmat. Dry fodder in two regions increased up to third year and then decreased, but in sum the total dry yield was higher in Zagheh than Ghaed Rahmat. Those cultivars with highest dry yield had highest height.

Iran With vast area of rangelands needs a usable method for data collection and analysis, for management purposes. Geographical Information System is a toll which has proved good advantages in this kind of studies and has a high capability for spatial data analysis and combination of the tematic maps data as well. Output of collected data and tematic maps could be used in management plants and designing of range improvement programs successfully. The main objective of this study was to examine the capability of GIS in preparing the environmental units and range improvement sits, and finally to produce a range management plan and model for a specific area.The Systematic method is the most common practice used in most studies to produce the uniform environmental units. Most references indicated that selection of useable layers and suitable classifications of these layers have great importance in these studies.The area under study was Margoon Research Station Located 65 Km. North-West Yasoodj. Basic data such as slope, aspect, elevation, soil depth and texture, range condition and trends were collected carefully. Different layer of information prepared precisely, and the uniform units were produced progressively. Finally the management plants such as grazing systems, reseeding and enclosure plots were specified and scheduled for the area under study. In has to be notified that for large-scale planning, some additional data such as climatological, geological, isotherm and isohythal data could be used as well.Overall conclusions indicated that the area under study has a great potential for improvement practices and GIS is a useful tool for immediate analysis and combination of information layers and finally, it is a good measure for management plants of the rangelands.

Two valid organizations (FAO & UNEP) introduced a new method to evaluate desertification process and provide land vulnarability map. Since Iran, because of its dry climate and sensitive ecosystem, has a great potential in affecting the environment, the feasibility of using this method, as a professional instrument all over Iran, was investigated for enacting the environmental management system to support natural reserves. To do so, the country's information base in environmental studies has been searched. Through 14 studies, the Ministry of "Jahad-e Sazandegi" with 6 studies and "Ministry of Agricultural" with 4 studies were more qualified.Potential of these surveys were evaluated and determined based on the efficiency of "FAO & UNEP" method. Among them, comprehensive studies of agricultural and natural resources restoration and development, presently researched by the Institute of Planning and Agroeconomy, have the highest efficiency grade (5.93) in methodology's feasibility in Iran.Based on results, the possibility degree of "FAO & UNEP" method shows that it is totally acceptable and, "59.3%" of their criteria are measurable. The most important defects of these studies consist of: statistical heterogenity and low efficiency in wind erosion's inventory.At last it is proposed that executive strategies must be taken to increase the efficiency of studies and making the proposed methods practicable in enacting environmental management in Iran.

More attention has been paid to Haloxylon species than To any other desert plants in arid and semiarid regions of Iran. It is necessary to irrigate and cure this plant in the first year of establishment. In different regions, amount and regime of watering depend on climatic and edaphic factors.An experiment was conducted in yazd-Ardakan desert to evaluate the Hect of irrigation and different mulch cover on establishment and canopy cover of Haloxylon spp. Water treatments including 20, 50, 100 and 150 liter per plant, irrigation regims (two, three and four times two years) and mulching cover (thin golyethlene sand and without much) were applied in a split-split plot design.The results should that in the first year, the Hect of different amount of water and mulching wee insignificant in the plant establishment but in the third year after planting, their Hects was obvious;The Hect of irrigation regimes on the plant establishment and canopy cover was significant (1% and 5% respectively).Mulching exerts a beneficiat Hect. on the establishment and/ canopy of the plants. Plyethlene was the best mulch. It retains water and is important for moisturt retention in the soil. Trrigation with (100 liter/plant) during two years along with polyethylent mulch incrensed the plant establishment by 91.67% relative to the control; In conclusion, irrigation regimes (150 liter/dant, four times at 2 years) along with polyethylene mulching increased canopy cover of the plant to 1732 cm2. relative to the control (962-6cm2).Sand mulching was not attested the establishment and company cover of the plants.