جستجوی مقالات مرتبط با کلیدواژه « بافق » در نشریات گروه « آبخیزداری، بیابان، محیط زیست، مرتع »

Mining and its various stages is one of the important factors in spreading pollution in natural environments. Contaminations may affect soil and water resources and actually enter the food chain due to absorption by plants. Among mineral elements, lead is more important because of its toxic effects. In order to investigate distribution of lead in downstream soils of Kushk Lead and Zinc Mine and identify anthropogenic and geogenic natures of pollution spread, a classified random systematic sampling was carried out. Sampling interval was 500 to1500 meters and soils were sampled in 0-5 and 5-30 centimeters depths. A control sample area with similar characteristics was considered in the vicinity of the region. The samples were analyzed by ICP-MASS method and the lead content of the samples was determined. Using Enrichment Factor and Geoaccumulation Index, the extension and severity of pollution are determined and related maps are prepared. Conclusions show that average amounts of lead in topsoil is about 4 times of subsoil and one kilometer far from mine, lead content of soil is more than 290 PPM that is more than permissible amounts. Moreover, the difference between lead content in topsoil and subsoil shows that the contamination in these areas is anthropogenic. Contamination reduces by going further from mine and the highest amount of emission of lead is around the main watercourse.

This study investigated the effects of seasonal changes and different soil conditions on proline, soluble sugars, and ion content of Hammada salicornica in Bafgh area, Yazd province. Three Hammada salicornica habitats with various environmental conditions were selected. The first habitat had salty soil and hardpan (Hamada habitat), the second habitat located next to playa with saline soil and high groundwater table, and the third habitat characterized by sandy soil. The plant samples were collected in four seasons with five replications. The highest Proline content in the species was observed (2.5 mg/gwt) in autumn in sandy habitat and its lowest value was found (1 mg/gwt) in Hamadat habitat. The highest amounts of soluble sugar (2.5 mg/gwt) were measured in summer in sandy and playa habitats and its lowest amount (0.87 mg/gwt) was observed in winter in sandy habitat. The highest amounts of sodium content (42 Meq/l) measured in winter in Hamada habitat and its lowest amount (.64 Meq/l) found in winter in sandy habitat. The highest amounts of potasium (31 Meq/l) were measured in winter in Hamada and sandy habitats and its lowest amount (0.6 Meq/l) were found in all habitats in winter. The highest amounts of nitrogen content (2.6 percent) were measured in Hamada habitat and its lowest amount (1.1 percent) was also found in winter in Hamada habitat. It is concluded that hammada salicornica can adjust its osmotic potential with absorbing and increasing its sodium and potassium content. This study showed that physiological responses of hammada salicornica to environmental conditions depend mostly on plant phenology and the kind of stress as well as their interactions.

Known of ecosystem of range details and relation bet ween this details including soil and vegetation, is Necessary for optimum management of ranges. To determine the effect of some soil properties on species distribution of Dorema ammoniacum and Rheum ribes in ranges of Baghedar region, Information of vegetation were harvested with systematic-random method in the form of 40 plots and during 4 transects. After drilling soil profiles in beginning and end of each transect and samples of 0-10 and 110-80 cm, the parameters pH, EC, CaCo3, organic carbon, CaSo4, Co3, Hco3, Cl, So4, Ca, Mg, Na, Fe, Cu and soil classification grain distribution was determined in the laboratory. After Collection of data for Analysis, it was used Principal components analysis method. The results of analysis between soil variables and vegetation show that soil texture, CaCo3, EC, OC, CA, Mg, Cl and Na had more impact on distribution of vegetation types and Dorema ammoniacum and Rheum ribes.

In order to optimum management of ecosystem of range, need details and relation between this details including soil and vegetation known. To determine the effect of some soil properties on species distribution of Eryngium bungei in Baghedar summer Bafgh region, Information of three types of vegetative plants were identified Artemisia aucheri - Eurotia ceratoides, Artemisia aucheri - Eryngium bungei and Artemisia aAucheri - Stipa barbata in the form of 20 plots were harvested for each type in the desert. After drilling 27 soil profiles and samples of 0-30 and 30-60 cm, the parameters pH, EC, CaCo3, organic carbon, CaSo4, gravel and soil classification grain distribution was determined in the laboratory. Analysis of variance showed that clay and CaCo3 in the soil first depth and CaCo3 in the soil second depth in three vegetation types with significant differences are. Principal components analysis on 16 soil variables and percent slope showed that the first principal component included percent slope, clay in the second depth and CaCo3 and sand in the first depth, explain 61% of the variations and the second components included sand in the second depth and electrical conductivity and organic matter in the first depth, explain 38% of the variations. The results show that Eryngium bungei be seen on soil with more clay in lower layer and more CaCo3 and less organic carbon and EC in upper soil layers.