Maryam Heidarian Aghakhani; Ali asghar Naghipour Borj; Hosein Tavakoli
Volume 17, Issue 2 , September 2010, , Pages 243-255
Abstract
It is important to know soil propoerties, particulary its chemical aspects, for the proper management of rangeland ecosystems. The aim of this study is to find the impact of grazing on vegetation and some soil chemical properties, in three areas, the key, reference, and critical, Sisab rangelands, Bojnord. ...
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It is important to know soil propoerties, particulary its chemical aspects, for the proper management of rangeland ecosystems. The aim of this study is to find the impact of grazing on vegetation and some soil chemical properties, in three areas, the key, reference, and critical, Sisab rangelands, Bojnord. The vegetation cover data was collected from 30, 1m2 quadrats in each area through random –systematic method. The soil data was sampled from two depths 0-15, 15-30 cm and five composite samples were collected (each sample was mixed of six samples) from each depth in the each area. Some factors such as the organic carbon, the percentage of soil organic matters, total nitrogen, absorbable phosphorus, pH and EC were measured. The results showed that carbon, nitrogen, soil organic matters, phosphorus, and EC were been decreased by grazing, but pH was increased. According to results, forbs were the dominant life form in the reference site. Shrubs cover percentages were been increased as grazing increased. In addition, reference site had species that are more palatable and invaders were more abundant in critical area. It was concluded that heavy grazing intensity cause to decrease of vegetaton and conversion of composition of the species cause to negative conversion in alimentary mineral of soil, sustainable of ecosystem would be endangered.
Hosein Tavakoli; Abbas ali Sanadgol; Uosef Garivani
Volume 13, Issue 2 , February 2006, , Pages 69-73
Abstract
Russian brome (Bromus tomentellus) is a prennial grass with good adaptability to climatic condition of north Khorasan. So, it has promise for using in range improvement projects. Because threre is no enough local information about mangement of this plant, the present experiment has been conducted in ...
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Russian brome (Bromus tomentellus) is a prennial grass with good adaptability to climatic condition of north Khorasan. So, it has promise for using in range improvement projects. Because threre is no enough local information about mangement of this plant, the present experiment has been conducted in Sisab Reaserch Station (SRS) to evaluate the response of this species to grazing intensities and rest grazing. Four grazing intensities of light (20 to 45% of forage removal), moderate (45- 65% of forage removal), heavy (65- 80% of forage removal) and without grazing as control applied by herd of lamb and sheep for three consequent years from 1999 to 2001. The year of 2002 considered as rest period from grazing. Herbage mass and number of plant per unit area measured as an index response. Herbage mass production decreased by reduction in precipitation. Heavy grazing resulted in significant reduction in herbage production and number of plants per unit area, but one year rest from grazing componsated the negative effect of intensive grazing on herbage mass reduction. Management implication based on this results show that plant can tolerate grazing intensity by 45-65% of herbage removal and indicate on the importance of rest grazing on survivance of this plant.