Kogin Waitetuna

**Kogin Waitetuna** wani kogi ne na Yankin Waikato na Tsibirin Arewa New Zealand . Yana gudana gabaɗaya daga arewa maso yamma daga tushe kudu maso yammacin Whatawhata don isa gabar kudu maso gabashin Tashar jiragen ruwa ta Raglan . 

## Ilimin ƙasa
Yawanci Upper Pliocene-Lower Pleistocene Okete volcanics ya fashe daga hanyoyi da yawa,  galibi suna samar da greywacke, tare da ƙananan yankuna na tephra. 

## Tarihi
Wani bincike ga Majalisar Yanki ya ce, "Harbour-wide sediment accumulation rate (SAR) ya kai 0.3-0.5 mm yr-1 a cikin shekaru 8000-6500 da suka wuce. Sakamakon saren gandun daji mai girma (1890-1920s), juyin juya hali zuwa makiyaya da dazuzzuka na Waaro da gandun daji na daban-daban (195) Hannun Waitetuna na tashar jiragen ruwa A hannun Waitetuna, 14C Dating na harsashi da bayanin martaba-pollen da aka adana a cikin ainihin 12B sun nuna cewa SAR na farko na 0.35 mm yr-1 ya karu sau uku bayan sare gandun daji da matsakaicin 1.1 mm yr-1 tun daga 1890. Pollen ya haifar da yawa. Ya ƙara ƙaruwa zuwa 2.5 mm yr-1 tun farkon 1990s A Okete Bay (core 10B) SAR kafin mutum ya kai 0.5 mm yr−1.

Mafi girma fiye da matsakaicin sashi na wancan canji bayan 1890 ya faru lokacin da 2,569 acres (1,040 ha) Puketutu block, kusa da estuary, da Watkins Brothers suka saya a 1901. Sun gudu da itacen itace a Raglan daga 1905 zuwa 1910, da yawa kogin kawo tare da katako da harboured saukar da tashar jiragen ruwa. A cikin 1907 Watkins suna sayar da kahikatea da rimu.

Kashe gandun daji ya faru ne bayan sayar da mafi yawan ƙasa a yankin ga mazauna. Kogin ya kasance iyakar babbar siyarwar ƙasa ta farko. "A ranar 22 ga watan Maris na shekara ta 1851, sarakuna goma sha takwas na Ngāti-Māhanga da Ngāti-Hourua, karkashin jagorancin William Naylor, sun sayar wa Sarauniya Victoria don adadin £ 400, kadada 19,680 na ƙasar da ke kan iyakar kudancin tashar jiragen ruwa. Yankin yammacin Whāingaroa Block, kamar yadda aka sani, ya fara ne a Putoe (wurin da garin Raglan yanzu yake tsaye) kuma ya bi kogin a gefen Hute, wanda aka haƙa da ita a gefen Aotea. "A nan ya juya zuwa arewa maso gabas don gudu (kuma a cikin layi madaidaiciya) na mil takwas ta cikin gandun daji mai yawa don saduwa da Kogin Waitetuna, 'yan mil na ƙarshe waɗanda suka kafa iyakar gabas. Yankin murabba'in kilomita 30 da aka kewaye ta haka ya haɗa da mafi yawan gonakin da ke tsakanin Dutsen Karioi a yamma da Waitetuna a gabas; tashar jiragen ruwa a arewa da Wharaa Plateau a kudu. Bayyanawa ga Sakataren mulkin mallaka a ranar 15 ga Afrilu 1852, bayan ya jawo hankali ga wannan gaskiyar cewa: "Yar ruwa ta biyu don samar da ita ce mafi girma ga wannan matsala, Ligar ya warware matsalar ta hanyar samarwa ta hanyar samar da ita, mafi girma, mafi girma ga wasu bangar ruwa". Hakanan ana shayar da shi sosai kuma yana da wadataccen katako don man fetur, don dalilai na gini ko don kasuwanci. "

## Shuke-shuke
Pollen analysis shows that the original vegetation was kahikatea on the flats, and a mixed podocarp-hardwood forest on the slopes, with tōtara, maire, matai, rimu, rata, beech and tree ferns. Kauri was present, but not abundant. From 1890 to 1930 80% of the forest was converted to pasture, though some pines have since been planted on former pasture, including  by Vela Holdings east of Mangaokahu Stream in 1990–1991. By the mid-1920s indigenous forest was restricted to the steeplands of Mount Karioi, Pirongia and the Moerangi Plateau.

## Fauna da ingancin ruwa
Dajin podocarp yanzu galibi gonakin tumaki ne da naman sa, tare da Te Uku Wind Farm a kusa da maɓuɓɓugar ruwa zuwa kudu. Wani bincike ga gonar iska  ya ce, "Ƙananan da matsakaicin matsakaicin . . . Matakotea Stream yana ba da kyakkyawan wurin zama na kifi, musamman ga inanga, kuma a cikin tsire-tsire masu kyau, banded kokopu. " Ya bayyana Waitetuna a bakinsa kamar yana da matsakaitan lafiyar muhalli. Wani binciken watan Janairun 2008 ya gano wadannan nau'ikan masu nuna alama don ingancin rafi kamar yadda yake a cikin Waitetuna inda ya shiga tashar jiragen ruwa kuma a cikin mahaɗanta, Matakotea Stream, (lambar da ke hagu sune MCI Score  - mafi girman maki, mafi mahimmanci waɗannan macroinvertebrates suna ga gurɓataccen yanayi. Kalmomin da ke dama suna nuna yadda aka saba ko kuma ba su da yawa a cikin Matakotea Stream / Waitetuna a saukowar Te Uku):

(8) mayfly  (*[[Deleatidium]]*) mai yawa / mai wuya

(7) caddisfly (Rhyacophilidae) lokaci-lokaci / lokaci-lokacin

(7) dobsonfly (Archichauliodes diversus)  mai ban sha'awa / lokaci-lokaci

(6) kwari na riffle (Elmidae)  6 na kowa / na kowa

(5) Caddisfly mai laushi (*Pycnocentrodes*)  lokaci-lokaci / lokaci-lokacin

(5) Crustacea (*Paratya curvirostris*) lokaci-lokaci / mai yawa

(4) kwari mai laushi (*Potamopyrgus antipodarum*) mai yawa / mai yawa

(3) yashi fly (*Austrosimulium*) na yau da kullun / lokaci

Cibiyar Bayanan Kifi ta NIWA  ta nuna cewa Waitetuna tana da longfin da shortfin eels, na kowa da redfin bully, galaxiids da inanga.

## Rashin gurɓataccen yanayi
Ma'aikatar Muhalli  ta nuna Waitetuna a bakinta yana da 600 E. coli a kowace 100ml (17th mafi muni daga 154), 620 faecal coliforms a kowace 100 ml (38th na 252), 0.49 MG / lita nitrogen (174th na 342) da 0.04 MG / lita phosphorus (140th na 361).  Ingancin yana cikin mafi munin 25% na koguna don E.coli, haske, turbidity da mafi munin 50% don nitrogen da phosphorus.&nbsp;&nbsp;

Wani binciken gwamnati ya ce, "Kogunan Waitetuna sun rubuta matsakaicin adadin Enterococcus kusa ko sama da 100/100 ml, lokacin da karatun 33/100 ml ake la'akari da matsakaicin matakin aminci don nishaɗin saduwa (watau iyo).  Kogin yana da 23 km (6.9%) na shinge, wanda ke rage gurɓataccen kayan gona.  Abinda kawai ya dace da ƙididdiga game da gurɓataccen shine na acidity.&nbsp;

Gurɓataccen ya inganta a 1.3% a kowace shekara don shekarun 1993-2017 don nitrate-N da 3.3% don 2008-2017 don bayyanar gani kamar yadda aka auna ta hanyar mahimman (watau yiwuwar gangara sama da 95% da RSKSE sama da 1% pa) ci gaba a cikin yanayin ƙididdigar gangara ta Kendall (RSKSE) (an daidaita rikodin kowane wata ta amfani da ƙuƙwalwar Lowess tare da 30%).  A cikin 2017, an ci tarar gonar kusan $ 50,000 don yin famfo a cikin wani yanki inda ya kwanta kusa da kogi, inda za'a iya ganinsa daga babbar hanya. Yana yiwuwa irin waɗannan abubuwan da suka faru a wuraren da ba su da yawa na iya haifar da binciken da aka samu a cikin 2011 cewa yawancin gurbataccen ruwa a cikin kogi suna lalacewa, duk da shinge da dasa shuka. Har ila yau, binciken ba shi da bayanan tushe.

## Dubi kuma

* Jerin koguna na New Zealand

## Bayanan da aka ambata

## Haɗin waje

* 1:50,000 taswirar http://www.topomap.co.nz/NZTopoMap/nz53407/Waitetuna-River/Waikato
* Ruwan sama a Karamu Walkway (kusa da tushe)
* Matsayin gurɓataccen yanayi

Hotuna na National Library 1910 -

* Saukowar Te Uku
* Babbar Te Uku
* Kogin Mangakino (ya haɗu da Waitetuna kusa da Te Uku) , Hotuna 3