razie shahbandari; Hossein Arzani; naser baghestani meybodi; Mohammad Ali Zare Chahouki
Abstract
The most important factor affecting forage quality is phenological stage that if it is recognized correctly, the appropriate grazing time will be determined. In this study, four species including Artemisia sieberi, Salsolakerneri, AelieniasubaphyllaandEurotiaceratoides in different phenological stages ...
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The most important factor affecting forage quality is phenological stage that if it is recognized correctly, the appropriate grazing time will be determined. In this study, four species including Artemisia sieberi, Salsolakerneri, AelieniasubaphyllaandEurotiaceratoides in different phenological stages (vegetative, flowering and seedling) were sampled. Samples were taken from the rangelands of Nodooshan-Yazd in 1389 and 1390. At each stage, five replicates for each plant species were selected and at least five vegetable bases from different locations of vegetation type in the region were selected. Samples were grinded after drying and separating different parts (flower, leaf and stem) and then they were analyzed using infrared spectroscopy in the laboratory. Important indicators of quality such as crude protein (CP), acid detergent fiber (ADF), dry matter digestibility (DMD) and metabolic energy (ME) were determined. Results showed that the highest percentage of crude protein is found in leaves of A. subaphyllaand in vegetative stage (9.19%), highest percentage of ADF is in shoot and in seedling stage (53.42%) and the highest percentage of DMD (48.13%) and the highest amount of metabolic energy (6.18 MJ/KgDM) is in leaves of A. sieberi and in vegetative stage, respectively. The end of the vegetative period can be considered the best time for grazing.
Abazar Esmali; Hasan Ahmadi; Mohammad Tahmoures
Abstract
The aim of this research is to describe the development of a methodology based on present knowledge and available data for evaluation of water erosion behavior and risk as well as modeling and estimation of soil erosion, which is compatible for other similar areas of Iran. Accordingly, the conducted ...
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The aim of this research is to describe the development of a methodology based on present knowledge and available data for evaluation of water erosion behavior and risk as well as modeling and estimation of soil erosion, which is compatible for other similar areas of Iran. Accordingly, the conducted research was based on four major types of water erosions including: sheet, rill, channel and riverbank which have considerable role on sediment yields of Baleghli Chay Watershed, Ardebil Province, were separately and spatially studied. In order to determine the inter-effects of effective factors, the study was conducted using stepwise multivariate statistical tests. For each erosion type, an individual model was then presented. In the next step, after determining of relations between sediment yield and environmental factors (fixed & variable) through statistical analyses and selecting of effective factors on erosion and sediment yields, was created an empirical structure for modeling erosion and sediment yields based on MPSIAC erosion model. In formulation of the new model, were used of eight effective factors on erosion in the area. These factors are susceptibility of geological formation, soil erodibility, rainfall erosivity, runoff erosivity, topography, hydrographic drainage, Normalized Difference of Vegetation Index (NDVI) and field conditions of erosion features. In the presented model, with summation of the scores of mentioned eight factors, obtains the M value, which can estimate the amount of erosion and sediment yields of the area, using exponential formula between sediment yield and M values. In addition, in order to obtain the confidence of presented model, it was used in "Nir" catchment for evaluation the precision. The results showed 11 percent difference. With accepting of this error value, the water erosion hazard map of the area was provided and presented using new model.
