A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need i...A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation.展开更多
In today’s life, because of industrial cities with long time of work, environmental pollutions and the aging of the population demanding to have leisure, recreation and outdoor recreations for every group of populati...In today’s life, because of industrial cities with long time of work, environmental pollutions and the aging of the population demanding to have leisure, recreation and outdoor recreations for every group of population, the necessity of construction a place for health outdoor recreation is obvious. Such a place would provide both entertaining in a happy family atmosphere and enjoying from fresh air, healthy food and nature cures like hydrotherapy, fish spa, herbs, acupuncture etc. for all the people from a kid to elderly guy and healthy to sick. This project was aimed to introduce and make a plan for constructing this site, known as wellness tourism center in Isfahan province, Iran. For reaching this purpose with taking advantage of original and second hand text, library resources, filed observations, specialist opinion on questionnaire, SPSS software and analysis and evaluation of statistical models with 2-square test, the best plan for this site has been suggested.展开更多
文摘A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation.
文摘In today’s life, because of industrial cities with long time of work, environmental pollutions and the aging of the population demanding to have leisure, recreation and outdoor recreations for every group of population, the necessity of construction a place for health outdoor recreation is obvious. Such a place would provide both entertaining in a happy family atmosphere and enjoying from fresh air, healthy food and nature cures like hydrotherapy, fish spa, herbs, acupuncture etc. for all the people from a kid to elderly guy and healthy to sick. This project was aimed to introduce and make a plan for constructing this site, known as wellness tourism center in Isfahan province, Iran. For reaching this purpose with taking advantage of original and second hand text, library resources, filed observations, specialist opinion on questionnaire, SPSS software and analysis and evaluation of statistical models with 2-square test, the best plan for this site has been suggested.
