NATURAL ECOSYSTEMS OF IRAN
Year:2011 | Volume:1 | Issue:2|Papers Count:9

Management practices impact rangeland structure and function. Rangeland assessment help interpretation and judgment about theses practices. The most important factors that cause rangeland to be disturbed are grazing intensity and land cultivation. So for investigation of these practices effect in arid rangeland, one shrub community was selected in Rudshor Save region. In this community, five cases included: three grazing intensity (heavy, moderate and weak), recently cultivated area and relict area that cultivated last years were investigated. Landscape function analysis (LFA) method was used to evaluate practices effects on soil surface characteristics and rangeland functional attributes investigated. In this method for determination of three functional attributes included: stability, infiltration and nutrient cycling 11 soil surface indicators included: soil surface cover (soil protection from erosion), perennial canopy/basal cover, litter (cover, origin, degree of decomposition), cryptogam cover, crust brokenness, type and severity of erosion, deposited material, soil surface roughness, soil surface resistance to distribution, slake test (soil stability test) and texture were used. Results showed that by increasing grazing intensity, perennial vegetation cover and soil surface resistance reduced.Also breaking soil crust created bare soil. Finally rill, terraces and pedestal erosions increased.Rangeland cultivation reduced stability and increased its infiltration. In relict area because of reestablishing perennial vegetation, soil indicator and functional attribute were improved. We found that LFA method able to show changes of management effect at last consumption a few money and time shows the capability of this method.

The dead trees are important component in forest ecosystems. In order to study of soil in dead trees around, in 98ha of Lirehsar forest used of strip transects with 10 m width and the whole dead trees recognized in direction. Every dead tree to settle in one of four classes that consist of: new dead tree, decay beginning, advanced decay, perfect decay. The soil to begin in four positions: dead tree below, 0.5 m distance of dead tree, 1 m distance of dead tree and control point. Carbon, nitrogen, C/N ratio, phosphorous, lime, pH and soil moisture Studied.73 dead trees recognized in region of species including beech, oak, maple, alder, and hornbeam. According to results dead trees of beech and oak to be increased carbon and lime. Hornbeam and alder to have statistics different on nitrogen, phosphorous, pH and soil moisture. Between different site positions, dead tree below positions to have the most value of soil characteristics. ExceptpH, the other factors around of dead trees with forth decay class (perfect decay) displayed the most value. However, lime and C/N ratio no statistics different begin decay classes.

Although it is necessary to know about nutrition value of range vegetation for range grazing management, but there is not enough information about it, It is essential to determine the vegetation value of range plants to evaluate the energy level available for animals and the appropriate time for utilization of plants and increasing the functioning of animals without damage to range plants, so for studying nutrition value of various plant species growing in different climates and vegetation stages, the Caragane Grandiflora was studied in three growing stages respectively growing, flowing and seeding stages. In each stage 3 samples and 3 replication in each sample was selected. Then the gathered samples were analyzed chemically using A.O.A.C method after drying out in laboratory. The mineral elements: N, P, K, Fe, Me, Cu, Zn, Ca and Mg were measured. Mean percent of high consumed elements Ca, P, N, K and Mg were 1.18, 0.13, 3.49, 0.13 and 0.63 respectively and for low consumed elements Fe, Mg, Cu and Zn were 520, 93, 9 and 64 ppm respectively. Variance analysis of data showed the effect of phonology stage on mineral elements.

This paper investigated and analyzed the Behaviour of sample indices for detection the spatial distribution pattern of Quercus brantii, Pistacia atlantica, Acer cineracense and Lonicera nummularifoliain oak mixed forests in northern of Illam province. In this research the area of plots was 2000 m2 that determined by minimal area method. Plots have established by random systematic method. In this study the spatial pattern detection indices included Morisita, standardized Morisita, green, lioyd's index of patchiness and variance to mean ratio, which their values calculated for every species in different sample size (20, 26, 35, 46, 55, 65, 75 sample plots) and their behaviour studied in relation to increasing the plot number. Result showed that all of the indices detected the clumped pattern for every one of species in different size of samples. However, levels of clumping varieties with increasing the number of samples. In this research concluded that the best index is the standardized Morisita index which is independent of sample size, species kind and population density. In this case green coefficient had behaviour better than the other indices except the standardized Morisita index.

On of the management aspeetes In the natural Resourcese is protection of Biodiversity in Natural Ecosystemes. Reckoniging of Relationships between productives and Biodiversitd Methods is of on of Most essential challenges on the natural resources Management. This Research have been done in the arid and semiarid Rangeland at the Bozdaghi Region in the Maneh and sam laghan city of Northern khorasan province, for investigation of impact of Rang land Fancing on the Biodiversity. For this porpuse, Tow plot selected as a fancing plot condition and a plot under creating and plot condition and then, in the each plot, the percentage, of vegetation of canopy and Density has been Measured by one hundred of Quadrate.as a Random on the Rangland area. Indexes of diversity, uniform shape, and lie? involving, shanon – winer - Mackintash and Jack-nioph by the Bio-DAP of software for testing the Meaning full of plots Data of diversity has been used T-student Test. The results shows the diversity and The results show, the rates of diversity and li? richment of species plants has been increased in Fancing region versus to region under Graging, but the graging hasn’t not much impact on uniform species plant, due to, Annual species and. At the end, it can be get tesultes that, doing the correct Management a long with omi the or decreasing the animal, it can create sustainable Ecosystem and also duet increasing the Biodiversity.

The increase of carbon dioxide concentration in atmosphere is the main cause of climate changes.That can damage damaging and change the ecosystems and thus the consequence loss biodiversity.Thus, preventing the entry and decreasing atmospheric carbon dioxide is seems essential. Watersheds are important in each region as the largest physical and topographic units with diversity of ecosystems.Soil, one of the main components of these ecosystems, that it is the main sources of stored carbon in global that it has the important role to balance and sequestration of carbon dioxide. In order to estimating of soil carbon sequestration, the Noumeh Roud watershed was selected under five treatments including: abandoned lands, rangelands, dens forest, semi-dense forest and sparse forest.Soil sampling was carried out randomly from0-30 cm depth in three points or more a square-kilometer network (in topographic map) totally eighty five soil samples were selected out in the land use. The soil samples were primarily dried in the free space and it is then sieved under 2 mm in the library.Measuring of organic carbon was done using Walkley-Black method. The results showed the different lands uses have difference effects on the amount of carbon sequestration. So that forests and rangeland had maximum and minimum carbon sequestration in unit area allocated library. Also, the factorial of land use area in carbon sequestration per unite land use have shown that, dense forest and sparse forest were having maximum and minimum carbon sequestration regularity. Although the amount of rangelands carbon sequestration was minimal in area unit, but the extent of these areas on the field, the amount of carbon sequestration has enjoyed high. Overall the amount of carbon sequestration soil in this area has more than 311473 tons.

Landslides and mass movements were considered natural hazards, except processes that are isolated may be small but occur in a region prone at different times. The final goal of the assessment and study of landslides can be ways to reduce damages caused by cited the need to use same in the zoning states that the landslide. Therefore the hierarchical analyses were used in the Vaz Watershed. Assessment landslide factors in Analytic Hierarchy Process approach based on priorities including: geology, road, slope, drainage, land use, rain, slope aspect, elevation and fault that geology is highest weight factor (0/303). Finally, landslide hazard map was prepared by four risk classes low, medium, high and very high was divided there for medium risk was most surface. The Base this map most landslides were in the formation Elika and Shemshak. Road construction also caused many landslides around it has been. The other hand, high class risk and very high in the forest environment that demonstrates the role of trees in INCREASE weight soil mass and occurred landslide.

Estimate of herbage production with the purpose of determining grazing capacity for the optimal managing of rangelands, is an essential and unavoidable activity. Some studies and researches have shown that there is a more appropriate regression relationship between annual production and effective precipitation compared with other continental variables. For this purpose, an area from rangelands of Siah Aftab of Garmsar as a model of semi stepp rangelands of Semnan province was determined. Since 1377 to 1388, annual herbage production of the area was measured by using 60 plates measured 2 square meters; double sampling along with 4 transects measured 400 m through a random-systematic sampling method. The variable such as annual rangeland production and also variables including monthly, two- month, seasonal and annual precipitation were determined as dependent variable and independent variables respectively and their relationships were analyzed by linear multi– variables regression program through stepwise. The result shows that there is a relationship between annual herbage production and total precipitation in February and March (growth season). According to these findings, it seems that it is possible to Estimate the amount of herbage production based on February and March precipitation.

In this research studied root depth characterize and Euphorbia seguieriana (Neck.) Species biomass density of Til range plants from Shabestar environs for using in slopes drabbling. Balance rain is yearly average area max 250 mm and most rain is Usually in Ordibehsht season. Soil Biomass density depends on Species, plant age, place and as perennial Plants increase, soil biomass density will increase. The results of this research showed that Euphorbia seguieriana Species with 34.50 root depth and average stem height 40 cm and average over ground of plant biomass is 2.70 gr/m2 and average under ground of plant biomass is 2.10 gr/m2 and indicated that the root of rangeland shrubs can stabile slope soil.