Savanna
Savannah ko savanna ya kasance wani yanki ne mai gauraya daji-ciyayi (watau ciyayi mai ciyawa) biome da yanayin yanayin da ke tattare da bishiyar da aka yi nisa sosai ta yadda alfarwar ba ta rufe ba. Buɗaɗɗen buɗaɗɗen yana ba da isasshen haske don isa ƙasa don tallafawa wani yanki na ciyawa mara karye wanda ya ƙunshi ciyawa. Akwai siffofin savanna guda huɗu; Savanna daji inda bishiyoyi da tsirrai suka zama wani haske mai haske, itacen savanna mai tarwatsewar bishiyu da ciyayi, da ciyayi mai ciyayi da bishiyoyi da ciyayi ba su da yawa.
Savannas yana kula da buɗaɗɗen alfarwa duk da yawan bishiyar. An yi imani da cewa savannas suna da yawa a sarari, bishiyoyi masu warwatse. Duk da haka, a cikin savannas da yawa, yawan bishiyar ya fi girma kuma bishiyoyi sun fi yawa a kai a kai fiye da dazuzzuka. Nau'in savanna na Kudancin Amurka cerrado sensu stricto da cerrado mai yawa yawanci suna da yawan bishiyoyi masu kama da ko sama da waɗanda ake samu a cikin dazuzzukan wurare masu zafi na Kudancin Amurka, tare da savanna daga 800 zuwa 3300 bishiyoyi a kowace kadada (bishiyoyi) da kuma dazuzzukan da ke kusa da 800-2000 bishiyoyi/ha. Hakazalika Savanna na Guinea yana da bishiyoyi/ha 129, idan aka kwatanta da 103 na gandun dazuzzukan magudanan ruwa, yayin da dazuzzukan Sclerophyll na Gabashin Australiya suna da matsakaicin yawan bishiyar kusan 100 a kowace kadada, kwatankwacin savannas a cikin yanki ɗaya.
Etymology
gyara sasheKalmar ta samo asali ne daga sabana na Mutanen Espanya, wanda ita kanta kalmar lamuni ce daga Taíno, wanda ke nufin "ƙasar ciyawa marar bishiya" a yammacin Indiya. Harafin b a cikin Mutanen Espanya, lokacin da aka sanya shi a tsakiyar kalma, ana furta shi kusan kamar Turanci v; don haka canza grapheme lokacin da aka rubuta shi zuwa Turanci.
Asalin kalmar ta shiga Turanci a matsayin Zauana a cikin bayanin tsibiran sarakunan Spayne daga 1555. Wannan yayi daidai a cikin kundin tarihin zamanin zuwa zavana (duba tarihin V). Peter Martyr ya ruwaito shi azaman sunan gida na fili a kusa da Comagre, kotun cacique Carlos a Panama ta yau. Lissafin ba daidai ba ne, amma galibi ana sanya wannan a cikin Madugandí na yau ko kuma a wuraren da ke kusa da bakin tekun Guna Yala daura da Ustupo ko kuma akan sauro na Point[24]. Wadannan yankuna a yanzu ko dai an mika su ga gonakin noman zamani ko kuma daji.
Rarrabawa
gyara sasheTsibirin savanna a Arewacin Ostiraliya yana nuna yanayin tazarar bishiya na yau da kullun na wasu savannas Yawancin wuraren ciyawa da gaurayawan al'ummomi na bishiyoyi, shrubs, da ciyawa an bayyana su a matsayin savanna kafin tsakiyar karni na 19, lokacin da aka kafa manufar yanayin yanayi mai zafi na savanna. Tsarin rarrabuwar yanayi na Köppen ya sami tasiri mai ƙarfi ta sakamakon zafin jiki da hazo akan girma bishiyar, kuma ra'ayi mai sauƙi ya haifar da ra'ayi na rabe-rabe na wurare masu zafi wanda ya ɗauke shi a matsayin "ƙananan yanayi". Yadda aka saba amfani da shi don kwatanta ciyayi yanzu ya ci karo da sauƙaƙan ra'ayin yanayin yanayi. Bambance-bambancen ya sa a wasu lokuta ana keɓance yankuna irin su savannas masu yawa a arewa da kudancin Kongo da kogin Amazon daga nau'ikan savanna da aka tsara.
Manazarta
gyara sashe- ↑ Anderson, Roger A., Fralish, James S. and Baskin, Jerry M. editors.1999. Savannas, Barrens, and Rock Outcrop Plant Communities of North America. Cambridge University Press.
- ↑ McPherson, G. R. (1997). Ecology and management of North American Savannas. Tucson, AZ: University of Arizona Press.
- ↑ Werner, Patricia A.; B. H. Walker; P. A Stott (1991). "Introduction". In Patricia A. Werner (ed.). Savanna Ecology and Management: Australian Perspectives and Intercontinental Comparisons. Oxford: Blackwell Publishing. ISBN 978-0-632-03199-3.