Magudanan ruwa na kogin lu'u-lu'u
 Magudanan ruwa na kogin lu'u-lu'u | |
|---|---|
| ambaliya | |
| Bayanai | |
| Ƙasa | Sin |
Kogin Lu'u-lu'u (ko Zhujiang) Basin yana daya daga cikin manyan kogin kasar Sin, dake kudancin kasar Sin, mai fadin murabba'in kilomita 453,700 a lardin Guangdong, da Guangxi, da Guizhou, da Yunnan, da Hunan, da Jiangxi da Fujian, da kuma wani yanki na arewa maso gabashin Vietnam.
Kogin lu'u-lu'u yana kunshe da manyan magudanan ruwa guda uku: kogin Xi, kogin Bei, da kogin Dong, da kuma kananan koguna masu yawa a cikin kogin Pearl Delta . Kogin Xi shi ne mafi girma a cikin tsawon kilomita 2,214, kuma matsakaicin gangaren kogin ya kai 0.58%. Kogin Bei mai tsawon kilomita 468 yana da matsakaicin gangaren kogin shine 0.26%. Tsarin ruwan Dong yana da babban rafi mai tsawon kilomita kimanin 520 tare da matsakaicin gangaren kogin shine 0.388%. Jimillar yawan ruwan da ake samu a duk shekara a duk shekara ya kai kimanin mita biliyan 345.8, wanda shi ne na biyu kawai ga kogin Yangtze na kasar Sin. [1].
Ambaliyar ruwa a kogin lu'u-lu'u na faruwa ne sakamakon ruwan sama kamar da bakin kwarya DA aka samu. Tunda kuma yankin kogin yana da fadi kuma tsananin ruwan sama yana da yawa, ambaliya a cikin tsaunukan tsaunuka na sama da na tsakiya suna da sauri, kuma babu tafkuna a tsakiyar kai. Don haka, idan aka ci gaba da samun ruwan sama mai tsanani, ambaliya ta kan yi ta da kololuwa da yawa a cikin dogon lokaci, tana jefa matsakaita da na kasa cikin hadari a cikin garuruwan da ake da kasa da yawan jama'a, da filayen noma da ke gefen kogin. wanda ke hana ci gaban tattalin arziki kuma yana shafar zaman lafiyar al'umma.
Halayen ambaliya
[gyara sashe | gyara masomin]Kogin Lu'u-lu'u na kogin ruwan sama ne kuma ambaliya ta fito ne daga ruwan sama mai yawa. Abubuwan da ke haifar da ruwan sama kamar haka:
Yanayin yanayi
[gyara sashe | gyara masomin]Tun da ruwan sama mai yawa ya shafi damina mai zafi , kuma sanyi da ƙungiyoyi masu dumi suna cikin jituwa. Har ila yau,, yana shafar yanayin yanayin, Kuma ya haifar da nau'in ruwan sama mai yawa, wanda yawanci yakan faru a watan Afrilu zuwa Yuli, mai suna farkon lokacin fa aka samu ambaliya.
Guguwa
[gyara sashe | gyara masomin]Ruwan sama mai yawa kuma yana shafar guguwar, wadda takan faru a watan Agusta zuwa Satumba, wanda ake kira lokacin ambaliya daga baya. Ruwan sama a lokacin ambaliya ya kai kusan kashi 80% na duk shekara. Siffofinsa sune: yawan ruwan sama mai yawa, tsananin ƙarfi da tsayi mai tsayi. Tsarin tsari na yau da kullun: Kogin Bei na farko, sannan kogin Dong da kogin Xi. Cibiyar guguwar ruwan sama: Kogin Bei yana yankin daga Yingde zuwa Qingyuan, kogin Dong yana yankin tsaunin Jiulian, Xunwu da Shangping, yayin da kogin Xi yana cikin tsaunin Miao a saman kogin Gui, da Xingren a Laowang. Dutsen da Duan a Dutsen Daming. Guguwar ruwan sama kamar da bakin kwarya a bakin rafin ta hada da birnin Haifeng zuwa Huidong dake a gabashin Guangdong, da Enping zuwa Yangjiang dake yammacin Guangdong, da Qinzhou zuwa Dongxing dake kudancin Guangxi.
Matsakaicin matsakaicin matsakaicin ruwan sama na shekara-shekara na 24h a cikin kwano shi ne kusan 100-200mm, ƙimar bambancin shine 0.35 ~ 0.65, kuma matsakaicin ruwan sama na shekara-shekara na 24h shine 848mm (Tashar Jinjiang Enching). Bambance-bambancen da ake samu a shekara-shekara na kwararar ruwa a cikin kwano ya yi daidai da ruwan sama, cewa yawan ruwan da ake samu a lokacin ambaliya daga Afrilu zuwa Satumba ya kai kashi 70% zuwa 80% na yawan ruwan shekara-shekara. Tun da yawan ruwan sama da yawan gaske a lokacin ambaliyar ruwa, yawancin magudanan ruwa suna da siffar fantsama, kuma ambaliya tana da sauƙin tattarawa cikin babban kogin a lokaci guda. Akwai tuddai da yawa a saman sama da na tsakiya, kuma saurin haɗuwar ambaliya yana da sauri. Babu ajiyar tafkin a tsakiyar tafki, wanda yana da sauƙi don haifar da ambaliya tare da kololuwa masu yawa da yawa. Mafi girman kololuwar ambaliya a kogin Bei da kogin Dong sau da yawa yana fitowa daga Mayu zuwa Yuni, kuma ambaliya tana ɗaukar kusan kwanaki 7 zuwa 15. Mafi girman kololuwar ambaliya a kogin Xi ya kan bayyana ne daga watan Yuni zuwa Agusta, yayin da mafi yawan ambaliyar ruwa takan faru ne daga watan Yuni zuwa Yuli, wanda ke daukar a ƙalla kwanaki 30 zuwa 45. Ambaliyar Xi ita ce babbar hanyar ambaliya a kogin Pearl Delta. A wasu lokuta ambaliyar ruwan kogin Xi da na Bei na haifar da munanan bala'i a kogin Pearl Delta.
Kowace shekara lokacin guguwa yana daga Mayu zuwa Oktoba. Ƙasar guguwa daga Shenzhen, Guangdong, zuwa Estuary River Estuary a Taishan . Guguwa mai karfin iska 8 ko sama a tsakiya tana faruwa ne akan matsakaita sau 2 zuwa 3 a kowace shekara, da kuma guguwa mai karfi na matakan 10 zuwa 11 duk bayan shekaru biyu 2 zuwa 3. Mamayewar guguwar, wani lokacin yana haifar da hawan guguwa .
Ambaliyar Ruwa
[gyara sashe | gyara masomin]Ambaliyar ruwa a cikin Kogin Lu'u-lu'u na yawan faruwa, musamman ma a tsaka-tsaki, ƙasa da kuma tudu. Littattafan tarihi sun bayyana irin wannan ambaliyar ruwa da yawa. Bisa kididdigar da aka yi, an samu ambaliya sau 125 a daular Ming a kogin Xi, sau 181 a daular Qing, da kuma sau 17 a Jamhuriyar Sin . An samu ambaliya guda 24 a kogin Bei kafin shekarar 1949 da kuma manyan ambaliya 14 a kogin Dong daga 1864 zuwa 1985. A cikin ƙananan raƙuman kogin Lu'u-lu'u da kuma a cikin delta, fiye da kadada a ƙalla 32,200 na ambaliya ya shafa ko kuma ya shafi filayen noma . Akwai sau 26 a karni na 18 da sau 36 a karni na 19. Daga shekarata 1915 zuwa Shekarar 1949, an sami sau 22 na ambaliya na noma wanda ya wuce kadada 66,700. An samu ambaliyar ruwa mai tsanani guda 12 tun daga shekarar 1949. Bayan shekarun 1990, ambaliya ta "94.6", "96.7" da "98.6" ta afku, wanda barnar ta yi matukar tsanani.
Ambaliyar Ruwa ta Musamman
[gyara sashe | gyara masomin]A watan Yuli na shekarar 1949, an fuskanci ambaliyar ruwa a kogin Xi da kogin Bei. Ambaliyar ruwan ta kasance wani kwale-kwale na kogin Xi sakamakon ruwan sama mai karfi da aka yi da tsarin yanayin yanayi na gaba. Ambaliyar ta samo asali ne daga kogin Lancang kuma kogin Liujiang ya fi girma. Kololuwar ambaliya ta tashar Wuzhou ta kai mita kusan 48,900 a cikin dakika guda, wanda ya yi daidai da ambaliya da aka shafe shekaru 50 ana yi. Nau'i ne na kololuwa guda ɗaya mai saurin gudu sama da cubic mita 30,000 a cikin daƙiƙa guda. Bayan kwanaki 18, ambaliyar ta kwanaki 30 ta kai mita biliyan 88.4, wanda shi ne na farko a cikin jerin ambaliya mafi girma na kwanaki 30.
A cikin watan Yunin shekarata 1959, kogin Dong ya yi ambaliya sakamakon ruwan sama mai yawa da aka samu ta hanyar yanayin yanayi na gaba. Ambaliyar ta samo asali ne daga Boluo . Tashar ta Boluo tana da ma'aunin kololuwar gudun mita 12,800 a cikin dakika daya da kuma rage darajar 14,100 cubic mita a sakan daya, wanda yayi daidai da ambaliyar ruwa a cikin shekaru 100.
A watan Yuni na shekarar 1994, an yi ruwan sama sau 13 a jere a kudancin kasar Sin. Kogin Xi da kogin Bei sun kasance a cikin shekaru 50 a lokaci guda. Lokacin da kogunan biyu suka yi ambaliya, sai suka shiga cikin layin kogin Pearl Delta. Ruwan ruwa a cikin yankin delta ya tashi sosai, kuma babban matakin ruwa ya dade na dogon lokaci. Fiye da kwanaki 10. Ambaliyar ruwa ta shafi garuruwa 70 na Guangxi da kuma gundumomi 39 a Guangdong, wanda ya haifar da kusan murabba'in mita miliyan 1.25 na filayen noma a Guangdong da Guangxi. Yawan mutanen da abin ya shafa sun kai miliyan 21.48, inda mutane 446 suka mutu, da kuma asarar tattalin arziki kai tsaye na kusan yuan biliyan 28.4.
A watan Yulin shekarar 1996, an yi ruwan sama kamar da bakin kwarya a kudu maso gabashin Yunnan da tsakiyar Guangxi na gabar kogin Pearl. Cibiyar guguwar ruwan sama ta kasance a tsohon yankin Kogin Bei. Daga ranar 12 zuwa 19 ga Yuli, ruwan sama ya kai 1,692 mm, kuma iyakar ruwan sama ya kai 779 mm a cikin sa'o'i 24 ya kasance Guangxi. Matsayi mafi girma na yankin Zhuang mai cin gashin kansa. Da misalin karfe 20 na safiyar ranar 19 ga wata, tashar Liuzhou ta nuna kololuwar ruwan da ya kai mita 92.43, wanda ya zarce matakin gargadin ruwan da ya kai mita 10.93, kuma yawan ambaliya ya kai 33700m³/s. Ruwa ne a cikin shekaru 130. Filayen noman da abin ya shafa ya kai murabba'in mita 480,000, kuma mutanen da abin ya shafa sun kai miliyan 8.17, tare da mutuwar mutane 249. Mafi girma a Guangxi. Kashi 90% na titunan birnin Liuzhou mai masana'antu sun cika da ambaliyar ruwa.
Daga ranar 5 zuwa 27 ga Yuni, shekarar 1998, an yi ruwan sama kamar da bakin kwarya a kogin Pearl. An yi mummunar ambaliyar ruwa a kogin Xi cikin shekaru 100 da suka gabata. Matsakaicin kololuwar ambaliyar ta kai mita 26.51 a tashar ruwa ta Zhangzhou tare da kwararar kololuwar 52,900m³/s, wadda ita ce ambaliya ta biyu mafi girma a tashar Zhangzhou tun bayan kafuwar jamhuriyar jama'ar kasar Sin. Bisa kididdigar da aka yi na lardunan Guangdong da Guangxi (yankin masu cin gashin kai), ba a samu karyewa a kowane bangare na kogin ba. Yawan mutanen da guguwar da ambaliyar ruwa ta shafa ya kai miliyan 14.98, yankin da amfanin gona ya shafa ya kai 903,300 hm², mutane 156 suka mutu, kuma asarar tattalin arzikin kai tsaye ya kai Yuan biliyan 16.03.
A farkon watan Yulin shekarar 2001, yankunan gabar tekun Guangxi da kogin Xi sun cika da ruwan sama kamar da bakin kwarya da guguwa mai lamba 0103 da mai lamba 0104, ta haddasa. Kogin Yujiang ya fuskanci ambaliya mafi girma tun kafuwar jamhuriyar jama'ar kasar Sin. A ranar 8 ga Yuli, tashar Hydrological ta Nanning ta nuna matakin kololuwar ruwa na 77.18m da iyakar gudu na 13400m³/s. Guguwa da ambaliya sun haddasa bala'in mutane miliyan 14.465 a Guangxi da Guizhou, mutane 32 sun mutu sakamakon bala'in, kuma asarar tattalin arzikin kai tsaye ya kai yuan biliyan 15.174.
Lokacin daga Mayu zuwa Oktoba shi ne lokacin mahaukaciyar guguwa a kudu maso gabashin kasar Sin. Karkashin guguwa mai karfi, wani lokacin ta kan kai ga tashin hankali, wanda ke haddasa rugujewar katangar tekun da ke gabar tekun gabar kogin Pearl Delta.
Matakan kariya
[gyara sashe | gyara masomin]Akwai ƙafar ƙafa 926,600 na ƙasar noma da ambaliyar ruwa ta yi barazana a kogin Pearl, wanda ya shafi al'umma miliyan 20. Ambaliyar ruwan Pearl ta fi ta'allaka ne a yankunan da suka hada da kogin Pearl Delta, kogin Lancang, da kogin Liutun. Waɗannan yankuna suna da yawan jama'a da haɓaka tattalin arziki. Ko da yake yawancin waɗannan wuraren suna da kariyar shinge, ƙa'idodin sarrafa ambaliya ba su da ƙarfi. Sai dai shingen Bei da ke Guangzhou, wanda ke kare kariya daga ambaliyar ruwa da ka iya faruwa a cikin shekaru 20, yawancinsu suna da kariya ne kawai na shekaru 10 da ake sa ran za a yi. Bisa ga ka'idar "haɗin daskarewa, iska da ajiya", a cikin 1980s, an tsara ayyukan sarrafa ambaliyar ruwa guda uku tare da dikes:
- (1) Haɗin gwiwar aikin shawo kan ambaliyar ruwa na tsakiya da na ƙasa na Yamma da Kogin Bei. Gina Tafkin Ruwa na Feilaixia a tsakiyar kogin Bei zai iya sarrafa magudanar ruwa na 34,097. km², wanda ya kai kashi 73% na Kogin Beitun. Ya fi ba da kariya ga ɓangarorin Guangzhou da ƙananan kogin Bei. Yankin fa'ida shine hekta 106,600 kuma yawan jama'a ya kai miliyan 3.38. Tafkin ruwa na Feilaixia yana ba da hadin kai tare da ƙarfafa Beijiang Dike don kare ambaliyar ruwa a cikin shekaru 100 da suka gabata, wanda ke ba Guangzhou damar jure shekaru 300-500 na ambaliya daga kogin Bei. Gina madatsar ruwa ta Longtan a kogin Hongshui a saman kogin Xi na iya sarrafa magudanar ruwa da yawansu ya kai kimanin 98,500. km² da karfin sarrafa ambaliyar ruwa na biliyan 7 m³ An gina Tafkin Da Tengxia a cikin birni, tare da yankin magudanar ruwa mai sarrafa kansa na 197755 km² da ƙarfin ajiyar ambaliya na biliyan 2 m³. Aikin hadin gwiwa na Dukkanin tafkunan Longtan da Datengxia na iya shawo kan ambaliyar ruwan kogin Xi yadda ya kamata. Tsarin aikin kula da ambaliyar ruwa wanda ya ƙunshi tafkunan ruwa guda uku na sama da magudanan ruwa masu kama da juna na iya tabbatar da kiyaye kiyaye ambaliyar ruwa a muhimman yankunan Guangzhou da Delta.
- (2) Tsarin injiniya na sarrafa ambaliya tare da diks na tsakiya da na ƙasa na kogin Yujiang. An gina Tafkin Baise a Yujiang, kuma yankin da ake kula da shi ya kai kusan 19,600. km². Ƙa'idar kula da ambaliyar ruwa na Nanning City za a iya haɓaka shi zuwa shekaru 50 ta ka'idar tafki. An sake gina Tafkin Laokou tare da hangen nesa, kuma yankin da aka sarrafa ya kasance 73,344 km², yana lissafin kashi 99.5% na yankin sama da Nanning. Haɗin gwiwar yin amfani da tsarin biyu zai ba da damar ma'aunin kula da ambaliyar ruwa na Nanning ya kai shekaru 100.
- (3) Haɗin tsarin aikin sarrafa ambaliya na tsakiya da ƙananan kogin Dongpu, sabon kogin Fengfeng da Maple Dam, yankin kula da Tafkin Baipenzhu shi ne 11,740. km², yana lissafin kashi 43.5% na yankin magudanar ruwa. Haɗin gwiwar amfani da tafkunan ruwa guda uku, tare da ƙarfafa magudanan ruwa, na iya ɗaga matakan kiyaye ambaliya na tsakiya da na ƙasa na kogin Dongjiang zuwa shekaru ɗari. [2]