نتایج جستجو برای: rare species

تعداد نتایج: 777083  

Journal: :Nature 1999

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Journal: :Nature 1999

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Journal: :Researches on Crustasea 1963

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Journal: :PLoS ONE 2009

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Journal: :Nature 1999

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Journal: :Proceedings of the National Academy of Sciences of the United States of America 1971
R Levins D Culver

A model is developed for the coexistence and exclusion of species over a region of similar habitable patches. Since the balance of local extinction and colonization would leave some patches unoccupied even without competitors, species may coexist even when all the patches are the same. Regional competition coefficients are found when species affect the local extinction or migration rates of eac...

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Journal: رستنیها 2008
A.H. PAHLEVANI,

During the study on newly collected and herbarium specimens belonging to the genus Euphorbia, three species, namely, E. gorenfloti, E. cheirolepioides and E. splendida were found to be synonymous with E. chamaepeplus, E. grossheimii and E. decipiens, respectively. Euphorbia sahendi as an interesting and rare species has been recognized after long time again among my material and Euphorbia delto...

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ژورنال: علوم آب و خاک 2001
آریاوند, احمد , فتح پور, حسین ,

Muteh wildlife refuge, with an area of about 220,000 ha, is situated at 95 km north of Isfahan. In this refuge, 511 species of vascular plants belonging to 284 genera and 59 families live along with 117 species of vertebrate animals belonging to 84 genera and 37 families. Rare plants of the area were classified into two categories of “endangered” and “vulnerable” according to IUCN, 1996 categor...

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ژورنال: تولید محصولات زراعی و باغی 2001
آریاوند, احمد , فتح پور, حسین ,

Muteh wildlife refuge, with an area of about 220,000 ha, is situated at 95 km north of Isfahan. In this refuge, 511 species of vascular plants belonging to 284 genera and 59 families live along with 117 species of vertebrate animals belonging to 84 genera and 37 families. Rare plants of the area were classified into two categories of “endangered” and “vulnerable” according to IUCN, 1996 categor...

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2014
Meha Jain Dan FB Flynn Case M Prager Georgia M Hart Caroline M DeVan Farshid S Ahrestani Matthew I Palmer Daniel E Bunker Johannes MH Knops Claire F Jouseau Shahid Naeem

The majority of species in ecosystems are rare, but the ecosystem consequences of losing rare species are poorly known. To understand how rare species may influence ecosystem functioning, this study quantifies the contribution of species based on their relative level of rarity to community functional diversity using a trait-based approach. Given that rarity can be defined in several different w...

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نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید

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