AliB. Mirgalili; MohammadR. Fazelpoor; fariba zakizadeh
Abstract
Grazing animals affect rangeland vegetation structure and function both directly and indirectly.These effects can be assessed in exclosures. In this study, vegetation changes inside and outside ofexclosures of Tanglaybid rangelands, located in south-western part of Yazd province, have beeninvestigated. ...
Read More
Grazing animals affect rangeland vegetation structure and function both directly and indirectly.These effects can be assessed in exclosures. In this study, vegetation changes inside and outside ofexclosures of Tanglaybid rangelands, located in south-western part of Yazd province, have beeninvestigated. Vegetation changes study was carried out in 3 key areas inside and also 3 key areasoutside of exclosure and lasted for 5 years (2000-2005). Every key area included 3 transects of 100meters long and 40 meters intervals. The transects were selected vertical to slope, including 10fixed plots (2×1 m2). Vegetation cover, density and frequency percentage of each plot species weremeasured annually. The random- systematic method was applied as a sampling method. Vegetationchanges inside and outside of exclosure were assessed, in a completely random plan, applyingDuncan's test (P < 0.05). The results showed that vegetation cover percentages increasedsignificantly (P < 0.05), inside the exclosure comparing to outside of it. Mean coverage of annualand perennial grasses and also bushes, inside the exclosure comparing to its outside increased 47,38 and 7%, respectively. Thus, in present research, exclosure has positive effects on vegetationcover changes of several species. Frequency percentage results showed that there was no significantdifference, inside against outside the exclosure in 2000, 2001, 2002, 2003, and 2004. Regardingdensity, there was significant difference only in 2001.The results can be considered in futuremanagement of the area's rangelands and similar regions throughout Iran
Alibeman Mirjalili; Mohammad Musaei Sanjeraei; Shahabodin Zarezadeh Mehrizi
Abstract
A better understanding of rangeland vegetation cover and its variation in different years basedon wetness and droughtiness fluctuations is a great importance. Economical priority setting ofrangelands is based on variations in rainfall and drought patterns, because it yields to bettercharacterization ...
Read More
A better understanding of rangeland vegetation cover and its variation in different years basedon wetness and droughtiness fluctuations is a great importance. Economical priority setting ofrangelands is based on variations in rainfall and drought patterns, because it yields to bettercharacterization of vegetative cover. Yet a comprehensive and continuous monitoring ofvegetative cover of rangelands has not been established. To study the influence of droughtinessand wetness on vegetation cover and production forage, 11 sampling areas and 3 referenceareas were selected in Herat. Three 100-m transects were located 25-m apart within eachsampling area. Production and cover were estimated within 10 located 2- plots along eachtransect. Data were analyzed using Duncan›s test Design a completely random with a factorialGLM procedure at 99% and 95% confidence levels. Results showed that the vegetation coverand production in wetness were significantly different from those in droughtiness (P<0.01).The vegetation production and cover increased by 36.3% and 34% respectively in the wetnesscompared to the droughtiness. The influence on production and cover was positive and efficientin the wetness with the average rainfall higher than the 30-yr average. Finally, the results offlood spreading increased vegetation cover and production forage in dams.
