نتایج جستجو برای: the species diversity

تعداد نتایج: 16168662  

Fish sampling was conducted to evaluate the species diversity of fish in 4 stations in Sanandaj Azad dam ecosystem seasonally from summer of 2017 to spring of 2018. A total of 1057 fish were caught in 12 species, of which more than 80% were caught in the lake behind the dam. The Cyprinidae family had 11 species with the most species diversity and only Sasanidus kermanshahensis belonged to the N...

Journal: :iranian journal of ichthyology 0
hamid reza esmaeili ichthyology and molecular systematics laboratory, department of biology, college of sciences, shiraz university, shiraz, iran. hamidreza mehraban ichthyology and molecular systematics research laboratory, zoology section, department of biology, college of sciences, shiraz university, shiraz, iran keivan abbasi inland waters aquaculture research center. iranian fisheries sciences research institute. agricultural research, education and extension organization, bandar anzali, iran yazdan keivany department of natural resources (fisheries division), isfahan university of technology, isfahan, 4156-83111, iran. brian w coad canadian museum of nature, ottawa, ontario, k1p 6p4 canada.

this checklist aims to reviews and summarize the results of the systematic and zoogeographical research on the iranian inland ichthyofauna that has been carried out for more than 200 years. since the work of j.j. heckel (1846-1849), the number of valid species has increased significantly and the systematic status of many of the species has changed, and reorganization and updating of the publish...

Trees are the most important biological elements of forest ecosystems. The variability of the tree species composition inhabiting in the Oriental beech forest, not only forms different forest types but also has a remarkable impact on the species diversity of forest floor plants, due to the existence of trees in the overstory layer. In this research, forest types of an an Oriental beech were ide...

it is not possible to understand developments of a country’s culture and civilization without knowing his believes and myths. whether it is north or south, east or west, planes or mountains, sahara or deserts, here in iran every corner includes valuable and precious treasures which are known all over the world, and cultural – historical objects which are found here adorn all well known museums of the globe. zagros mountains, lorestan province locating at the heart of that, are not only the same, but are more prominent than other iranian regions. you can not find someone who does not know what the lorestani bronzes are, and there is no museum that not be pride of having a piece of that. the said bronzes which are manufactured four millenniums b.c. are admired nearly by all those researchers because of their beauty, diversity and technique. lorestani artistic works including stone engraves, bronzes and clays, show an ideal and metaphysical world beside real world which explain mental system of human beings on that era against sensations and phenomena happening around them. men main mental occupation on that time was he unknown world which had surrounded them, and they used to use the religion to fight life’s natural factors, and art was a tool of religious and mythical painting which was far from reality and had entered into the abstract domain. as natural objects have become subjects of lorestani art, it cleanses them from any non – intrinsic limitations and external factors which surround them and darken their meanings, and just shows their main specifications. artist in the said civilization is not searching for realism. although these are few works showing the nature, but in effect there is no wish to imitate touchable factors of the nature, and artist has turned real phenomena to encoded signs as per his own mentality. this procedure is called stylization.

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده هنر و معماری 1391

it is not possible to understand developments of a country’s culture and civilization without knowing his believes and myths. whether it is north or south, east or west, planes or mountains, sahara or deserts, here in iran every corner includes valuable and precious treasures which are known all over the world, and cultural – historical objects which are found here adorn all well known museums...

Plant species distribution, composition and diversity in deserts of arid and semi-arid areas, especially saltland; depend on soil physical and chemical gradients. The aim of this research was to investigate changes in the plant species diversity and richness along a soil salinity gradient in the margin rangelands of Petregan Playa. After vegetation zoning in relation to soil salinity, random-sy...

Adel Sepehry Hasan Vahid Mousa Akbarlou Negin Nodehi,

One of the main objectives of ecosystem management is to preserve the speciesdiversity. Many researchers regard higher species diversity as the stability of ecologicalsystems. The aim of this study is to investigate the stability and relationships betweentopographical factors with diversity indices in Ghorkhud mountainous rangeland innorthern Khorasan province, Iran. For data sampling (2012), l...

Plant diversity and vegetation distribution in an area are related to the soil physical and chemical properties. The knowledge of relationships between species diversityand soil parameteris essential for sustainable ecosystem management. This study was conducted to investigate the relationships between soil factors and species diversity indices in the protected rangelands of Lashgardar, Malayer...

Journal: :مرتع و آبخیزداری 0
قدرت اله حیدری استادیار دانشکدة منابع طبیعی دانشگاه علوم کشاورزی و منابع طبیعی ساری حمید رضا سعیدی گراغانی دانشجوی دکتری مرتع داری دانشگاه تهران

assessment of diversity and species richness in the understanding of ecosystem functions, protect and preserve genetic resources, evaluation and control of environmental change and the success or failure will help natural resource management programs. arbitrary banning livestock grazing program and one of the most common and perhaps the most degraded pastures and reduced the diversity and speci...

It has been paid less attention to effect of environmental factors on species richness and diversity indices in fragile ecosystems around Playa. Therefore this study was conducted to evaluate the effect of geographical directions and distance from Playa salt layer on the composition and species diversity in Sirjan Playa, Kerman Province, Iran. Determination of intervals 10, 1000 and 2000 mete...

Biodiversity is one of the important concepts in ecology and vegetation management, and plays an important role in the health, production, and evaluation of ecosystems. Species diversity is a major part of biodiversity and one of the most important parameters of ecosystem changes. In this research, the data of the rangeland evaluation different climate zones of Isfahan province were used in fiv...

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