Desertification in Africa

Yaduwar hamada a Afirka wani nau'i ne na lalacewar ƙasa wanda ya haɗa da jujjuya ƙasar mai amfani zuwa hamada ko wuraren da ba su da ruwa. Wannan batun damuwa ce ta muhalli da ke haifar da babbar barazana ga rayuwa miliyoyin mutane a Afirka waɗanda suka dogara da ƙasar don rayuwa. Nazarin yanayin ƙasa da muhalli kwanan nan sun kirkiro kalmar hamada. Desertification shine tsari wanda wani yanki na ƙasa ya zama hamada, kamar yadda kalmar hamada ke nunawa. Rashin ko lalacewar yiwuwar halittu na ƙasar ana kiranta hamada. Yana rage ko kawar da yiwuwar samar da shuke-shuke da dabbobi a ƙasa kuma yana da wani bangare na lalacewar yanayin halittu. Bugu da ƙari, ana amfani da kalmar hamada musamman don bayyana lalacewar wuraren da suka bushe a duniya, ko kuma yanayin da ya bushe, rabin bushe, da kuma yanayin da ba shi da zafi. Wadannan yankuna na iya zama nesa da abin da ake kira hamada ta halitta ko yanayi, amma har yanzu suna fuskantar damuwa ta ruwa mara kyau saboda ruwan sama mai yawa da canji. Suna da saukin kamuwa da lalacewa daga matsin amfani da ƙasa na mutum. Abubuwan da ke haifar da hamada sune haɗuwa da abubuwan halitta da na ɗan adam, tare da Canjin yanayi wanda ke kara matsalar. Duk da haka, akwai kuskuren ra'ayi cewa hamada a Afirka sakamakon abubuwan halitta ne kawai kamar canjin yanayi da rushewar ƙasa. A zahiri, ayyukan ɗan adam kamar sare daji, wuce gona da iri, da ayyukan noma marasa dorewa suna ba da gudummawa sosai ga batun. Wani kuskuren ra'ayi shine cewa, hamada ba za a iya juyawa ba, kuma wannan ƙasar da ta lalace har abada za ta kasance wuraren da ba su da amfani. Koyaya, yana yiwuwa a dawo da ƙasar da ta lalace ta hanyar ayyukan kula da ƙasa masu ɗorewa kamar sake dasa bishiyoyi da kiyaye ƙasa. Yankin 10.3 miliyan km2, ko 34.2% na farfajiyar nahiyar, yana cikin haɗarin hamada. Idan aka yi la'akari da hamada (Sahara da Kalahari), yankin da abin ya shafa kuma wanda zai iya shafa kusan kilomita miliyan 16.5 ne ko 54.6% na duk Afirka. Kashi 5.7 cikin dari na farfajiyar nahiyar ta ƙunshi yankuna masu tsanani, kashi 16.2 cikin dari na yankuna masu tsananin gaske, da kuma kashi 12.3 cikin dari na matsakaici zuwa yankuna masu sauƙi.

 Matakan hamada daban-daban 
Dangane da ka'idoji uku: yanayi, rauni na asali, da matsin lamba na mutum da dabbobi, Majalisar Dinkin Duniya ta amince da digiri huɗu na haɗarin hamada: mai tsanani, mai tsanani, matsakaici, da ƙarami. Lokacin da ƙasa ta zama ba za a iya amfani da ita ba, an ce ta fuskanci mummunar hamada. Misalan wannan sun haɗa da dunes masu motsi, manyan tsarin rami, da gishiri mai gishiri, kusan ƙasa mai ruwa a wuraren da aka ban ruwa a baya. Wadannan yanayi ana zaton ba za a iya juyawa ba. Ana rarraba hamada mai tsanani da matsakaiciyar hamada bisa ga girman hanzarin lalacewar ƙasa da lalatawa, canji zuwa ganyayyaki marasa kyau, ko asarar amfanin gona saboda salinization mai juyawa ko ƙasa mai ban ruwa. Inda babu lalacewar shuka ko ƙasa, ana wakilta shi da rukuni na biyu, ɗan hamada.

 Tarihi 
Kalmar hamada galibi ana danganta ta da aikin masanin tsire-tsire na Faransa André Aubréville na 1949 a kan gandun daji na Afirka, kodayake bincike ya yi iƙirarin cewa ana iya gano shi zuwa ƙarni na 19 na mulkin mallaka na Faransa na Arewacin Afirka. Kwamitin Nazarin  ya ba da umarnin bincike don bincika ci gaban prehistoric na hamadar Sahara, wanda ya haifar da abubuwan da suka faru a lokacin. Wannan abu ya kasance a cikin dubban shekaru a Afirka kuma ba sabon abu bane. Koyaya, yayin da yawan jama'a suka karu kuma ayyukan ɗan adam sun karu, hamada ta kara tsanantawa sosai a cikin 'yan shekarun nan.

Za'a iya gano hamada a dubban shekaru a Afirka, tare da shaidar da aka gano a cikin tsoffin wallafe-wallafen da takardun archaeological. Koyaya, girman da tsananin matsalar sun karu a cikin 'yan shekarun nan sakamakon haɗuwa da abubuwan halitta da na ɗan adam. Yaduwar hamada ta zama matsala mai tsanani a Afirka a cikin karni na ashirin, wanda ya haifar da lalacewar muhalli da kuma jefa rayuwar miliyoyin mutane da ke dogaro da ƙasar don abinci cikin haɗari. A mayar da martani, gwamnatoci, kungiyoyi masu zaman kansu, da kungiyoyin kasa da kasa sun kirkiro mafita iri-iri, gami da sake dasa bishiyoyi, kiyaye ƙasa, da hanyoyin kula da ƙasa masu ɗorewa.

A cikin ƙarni da ya gabata, hamadar Sahara tana fadada ta fiye da kilomita 7,600 a kowace shekara kuma yanzu ta fi girma 10% fiye da yadda take a shekarar 1920. Yaduwar hamada da ci gaban hamada ba su da farko saboda canjin yanayi da mutum ya haifar, kamar yadda suke yanzu. Mafi girman hamada a duniya sun samo asali ne daga matakai na halitta waɗanda suka yi hulɗa a tsawon lokaci, kamar su ruwa, iska mai tashi, iska mai dumi, da ƙarancin zafi. Ayyukan ɗan adam, a gefe guda, kwanan nan sun zo don fadada ko kwangila waɗannan hamada. Don sanya gudummawar Afirka a cikin mahallin, Sahara tana fadada cikin sauri tun daga shekarun 1920, ta mamaye kashi 10% fiye da yadda ta yi a baya, bisa ga binciken da Gidauniyar Kimiyya ta Kasa (NSF) ta gudanar da masana kimiyya a Jami'ar Maryland (UMD).  Rashin ruwa na shekarun 1980 ba shine bala'in mutum na farko da ya faru a yankin Sahel ba. An yi amfani da hamada a cikin dogon lokaci na fari, wanda ya fi shahara shi ne fari da yunwa na Sahelian na 1968. Ya ci gaba har zuwa 1985 kuma yana da alhakin kusan mutuwar 100,000 da kuma rikice-rikice na miliyoyin rayuka. Amfani da albarkatun mutane (kamar wuce gona da iri da kuma sare daji) an fara tunanin shi ne kawai dalilin fari. Duk da haka, manyan canje-canjen yanayi na iya taimakawa ga fari. Duk da kasancewa yankin da ya fi fama da mummunar tasiri a Afirka, Sahel ba shine kadai yankin da Hamada ta Sahara ba. Karoo a Afirka ta Kudu, ya fuskanci yanayin tsaka-tsaki na shekaru 500 da suka gabata, Somaliya, wanda ya fuskanci manyan rikice-rikicen fari guda uku a cikin shekaru goma da suka gabata kadai, da Habasha, wanda ya ga kashi 75% na ƙasar da hamada ta shafa da babbar yunwa tsakanin 1983 da 1985.  

A cewar wasu masana kimiyya, abubuwan da ke haifar da mutane suna taka muhimmiyar rawa a cikin hanyoyin hamada, tare da yanayi shine babban dalilin. Sauran masu bincike sun sauya muhimmancin waɗannan dalilai guda biyu. Yankin hamada a Afirka ya samo asali ne daga karfi na halitta da na mutum. Canjin yanayi, wanda ya haifar da karuwar bushewa da raguwar ruwan sama a yankuna da yawa, da rushewar ƙasa, wanda ke faruwa ta halitta amma aikin ɗan adam na iya kara tsanantawa, sune manyan abubuwan halitta waɗanda ke haifar da hamada. Misali, yana iya zama da wahala a faɗi idan hamada ko fadada hamada shine sakamakon canjin yanayi ko aikin ɗan adam. Yaduwar hamada a Afirka ta kara tsanantawa ta hanyar abubuwan ɗan adam kamar su sare daji, wuce gona da iri, da hanyoyin noma marasa dorewa kamar monoculture da yawan amfani da taki. Misali, sare daji yana rage yawan tsire-tsire waɗanda zasu iya kafa ƙasa kuma su kare shi daga rushewa, yayin da wuce gona da iri yana rage ciyayi kuma yana fallasa ƙasa ga rushewa da lalacewa. Misali, an yi jayayya cewa gefen Sahara shine sakamakon aikin ɗan adam, tare da yanayi yana taka rawa kawai. Ƙungiya ta uku tana ba da kusan daidai ga mutum da muhalli. Hanyoyin kula da ƙasa marasa kyau, kamar juyawa na amfanin gona, amfani da kayan aiki masu nauyi waɗanda ke tattare da ƙasa, da hanyoyin kula da ruwa marasa dorewa, duk suna ba da gudummawa ga hamada. Binciken hakar ma'adinai da mai na iya ba da gudummawa ga hamada ta hanyar tayar da yanayin halittu da rage ingancin ƙasa. Yaduwar yawan jama'a da talauci na iya kara tsananta halin da ake ciki ta hanyar kara bukatar albarkatu da kuma haifar da ayyukan amfani da ƙasa marasa dorewa. Dukkanin wadannan dalilai sun ba da gudummawa ga lalacewar ƙasa mai kyau, suna haifar da babbar barazana ga rayuwar miliyoyin 'yan Afirka waɗanda ke dogaro da ƙasar don rayuwa.

A cikin Sahel, hamada galibi ana danganta shi da lalacewar iska. Don sanya shi a sauƙaƙe, rushewar iska shine abin da ke faruwa lokacin da iska mai ƙarfi ta cire saman ƙasa. Rugujewar iska tana rage abubuwan gina jiki a cikin ƙasa saboda ƙasa ta saman sau da yawa tana ƙunshe da abubuwan gina jiki fiye da ƙasa.Daniel HA , Langham WH (1936). The effect of wind erosion and cultivation on the total nitrogen and organic matter content of soils in the Southern High Plains. J. Am. Soc. Agron., 28, 587–596. Zobeck TM , Fryrear DW (1986). Chemical and physical characteristics of windblown sediment: II. Chemical characteristics and total soil and nutrient discharge. Trans. ASAE , 29, 1037–1041.  Wannan yana rage samar da ƙasa. Bugu da ƙari, asarar ƙasa na sama na iya fallasa ƙasa tare da halaye na jiki, wanda ke rage ƙarancin ƙasa. Bugu da ƙari, rushewar iska na iya hana ci gaban amfanin gona ta hanyar binne amfanin gona a ƙarƙashin yashi da aka hura kuma ya haifar da lahani na jiki (abrasion).  Michels K, Sivakumar MVK , Allison BE (1993). Wind erosion in the southern Sahelian zone and induced constraints to pearl millet production. Agric. For. Meteorol., 67, 65–77. 

 Yankunan da abin ya shafa 
Yankuna uku daban-daban na nahiyar sun shafi hamada: Afirka ta Bahar Rum, yankin Sudan-Sahelian, da Afirka kudu da Sudano-Sahel. Za a iya samun yankuna masu tsanani da masu tsanani a cikin ƙasashe biyar na Bahar Rum na Afirka: Masar, Aljeriya, Libya, Morocco, da Tunisia. Yankin Gasfa a Tunisia shine babban misali na yankin da ke cikin Bahar Rum wanda ya sha wahala sosai ko yanayin hamada. Yawancin kasashe 19 a yankin Sudano-Sahelian suna fuskantar irin wannan yanayi (mai tsanani zuwa mai tsanani), yayin da yawancin Afirka a kudancin Sudano-Sahel suna fuskantar haɗari mai sauƙi zuwa mai tsanani da ke da alaƙa da hamada. Kimanin kasashe 36 na Afirka sun shafar fari da hamada gaba ɗaya. Yankin Sahel, wanda ya hada da Senegal, Mauritania, Mali, Nijar, Chadi, Sudan, da Eritrea, ya sha wahala daga fari akai-akai, yawan kiwo, da kuma sare daji, wanda ya haifar da lalacewar ƙasa da hamada. A cikin ƙuntataccen ma'anar, kalmar yankin Sahel tana nufin yankin da ke da nisan kilomita 400 daga arewa zuwa kudu kuma kusan kilomita 4000 daga gabas zuwa yamma tare da kudancin tuddai na hamadar Sahara kuma tana fuskantar 200 zuwa 600 mm na ruwan sama na shekara-shekara a matsakaici. A cikin wannan wuri, ƙananan ruwan sama da aka gauraya da ƙasa mai ƙarancin amfani da yashi mai yawa (wanda aka bayyana dalla-dalla a ƙasa) yana haifar da karancin abinci mai tsanani, kuma ana iya haifar da yunwa mai ban tsoro lokacin da yankin ya sha wahala daga fari. A shekara ta 1974, akalla mutane 750,000 a Mali, Nijar, da Mauritania sun dogara ne kawai da taimakon abinci don tsira, kuma a lokacin fari wanda ya kasance daga 1972 zuwa 1984, akalla mutane 100,000 sun mutu. A cewar Ma'aikatar Tattalin Arziki da Harkokin Jama'a ta Duniya, kasashe shida na Sahel suna da yawan mutane kusan miliyan 30 a wannan lokacin.   Rashin ruwa na dogon lokaci da amfani da albarkatun kasa sun addabi Horn of Africa wanda ya hada da Somalia, Habasha, da Kenya. Rashin lalacewar ƙasa ya faru a Kudancin Afirka, gami da Zimbabwe, Botswana, Namibia, da Afirka ta Kudu, sakamakon dabarun noma marasa dorewa, wuce gona da iri, da kuma sare daji. Har ila yau, hamada ta shafi Arewacin Afirka, wanda ya haɗa da Masar, Libya, Aljeriya, Tunisia, da Maroko, sakamakon canjin yanayi, yawan kiwo, da ayyukan noma marasa dorewa. Rashin abinci da ruwa, ƙaurawar yawan jama'a, da asarar halittu duk tasirin hamada ne a waɗannan wurare, yana jaddada mahimmancin buƙatun ayyukan amfani da ƙasa masu ɗorewa da shirye-shiryen kiyaye muhalli a duk faɗin Afirka.

 Aikin noma 
Yaduwar hamada tana shafar kusan kashi 45% na yankin ƙasar Afirka, tare da kashi 55% a cikin babban ko matsanancin haɗari na lalacewa a nan gaba. Canjin yanayi da hamada suna da tasiri sosai a kan tsaron abinci ta hanyar tasirin su akan yawan aikin gona. Bayanai masu mahimmanci suna nuna mummunan tasirin canjin yanayi da hamada ba kawai a kan amfanin gona ba, har ma da yawan aikin gona da asarar kudin shiga a cikin ƙasashe masu bushe. Tsinkaya ga Afirka ta Kudu ta Sahara ya nuna cewa hauhawar yanayin zafi, karuwar yawan raƙuman zafi, da karuwar bushewa za su yi tasiri ga tsarin aikin gona na ruwan sama. Canjin yanayi zai rage matsakaicin amfanin gona ga manyan amfanin gona na duniya 11 - millet, eld pea, sugar beet, dankali mai zaki, alkama, shinkafa, masara, soya, groundnut, sunflower, da rapeseed - da kashi 15% a Afirka ta Kudu da 11% a Gabas ta Tsakiya da Arewacin Afirka ta 2050 idan ba a yi amfani da taki na carbon ba. Yaduwar hamada ta rage yawan aikin gona da kudaden shiga yayin da yake ba da gudummawa ga asarar halittu a yankuna masu yawa. Hakanan ana sa ran rage amfanin gona da dabbobi, canza kayan kwalliya na nau'ikan shuke-shuke, da rage bambancin halittu a duk ƙasashe masu bushe. Aikin amfanin gona a Afirka ta kudu da Sahara, musamman, ana iya rage shi da kashi 17-22% nan da shekara ta 2050 sakamakon canjin yanayi. A cikin 2017, kusan mutane miliyan 821 a duk duniya ba su da wadataccen abinci, tare da Afirka ta kai kashi 31%. Afirka ta kudu da Sahara, musamman Gabashin Afirka, tana da mafi yawan mutanen da ba su da abinci mai gina jiki a duniya a cikin 2017, tare da 28.8% da 31.4%, bi da bi. Kulawa na dogon lokaci a Arewacin Afirka (1978-2014) ya bayyana bacewar manyan nau'ikan shuke-shuke masu tsayi saboda fari da hamada, kamar Stipa tenacissima da Artemisia herba alba . 

A arewacin ɓangaren sahel, inda ruwan sama ba shi da yawa, ana yin noma da dabbobi bisa ga kiwo; a kudancin ƙasar, inda ruwan inabi ya fi iyakar noma (ruwan sama na shekara-shekara kusan 300 mm), amfanin gona mai tsayayya da fari kamar lu'u-lu'u (Pennisetum glaucum (L.) R. Br. ), sorghum (Sorghum bicolor (L.) Moench), cowpeas (Vigna unguiculata (L.) Walp), da peanuts (Arachis hypogaea L.) ana shuka su ba tare da ban ruwa ba. Duk da haka, saboda kusanci da iyakar noma, bambance-bambance masu yawa a cikin ruwan sama na shekara-shekara, da kuma faruwar bushewa, yana da ƙalubale don kula da amfanin gona. Tare da koguna na dindindin kamar Kogin Neja, ana shuka shinkafa. Wani fasalin noma a yankin Sahel shine haɗakar noma da kiwon dabbobi. An kafa tsarin symbiotic a nan. Bayan manoma sun girbe lu'u-lu'u ko sorghum, manoman dabbobi suna kiwon dabbobinsu (kwai, tumaki da awaki) a cikin filin kuma an mayar da turare zuwa ƙasar. Babbar dabarar don adana amfanin ƙasa ita ce shigar da sharar gida a cikin filayen da ke kusa da ƙauyen ko ƙauyen (kasa da 1 km). Filin da ke nesa da ƙauyen ko ƙauyen da farko an bar su ba tare da izini ba, yayin da filayen da ke kusa da ƙauyuka ana amfani da su da farko don yin dare, tsarin da ake ajiye dabbobi a cikin filin da dare ɗaya, suna samar da filin da tururi da fitsari.

 Tasirin Tattalin Arziki 
Yaduwar hamada tana da tasirin tattalin arziki a Afirka, musamman a wuraren da noma da amfani da albarkatun kasa sune manyan hanyoyin samun kudin shiga. Yaduwar hamada tana rage amfanin gona, tana haifar da karancin abinci, kuma tana kara talauci a cikin mutanen da abin ya shafa ta hanyar lalata ƙasa mai kyau da wadatar ruwa. Mutanen da suka rasa muhallinsu sakamakon hamada na iya haifar da karuwar gasa don karancin albarkatu da rikice-rikice, wanda ya kara matsalolin tattalin arziki. Sakamakon mummunar hamada a kan yanayin halittu da bambancin halittu na iya haifar da sakamako mai zurfi ga masana'antu kamar yawon bude ido da yawon shakatawa na muhalli, wanda ya dogara da yanayin halittu masu lafiya don jawo hankalin masu yawon budewa. Yaduwar hamada tana da manyan tasirin tattalin arziki a Afirka, wanda ke buƙatar ci gaba da ƙoƙari don rage tasirin hamada ta hanyar ayyukan amfani da ƙasa masu ɗorewa, kiyayewa, da maido da ƙasashe masu lalacewa.

 Yaki da hamada 
Tare da yankin Sahel ya fi rauni kuma ya shafi hamada sosai, an kaddamar da aikin da ake kira Great Green Wall a cikin 2007 don Sahara da Sahel. Babban burinta shine ƙirƙirar abin mamaki na halitta mai nisan kilomita 8,000 a duk faɗin Afirka don haɓaka yawan ƙasa mai kyau da ke kan iyakar hamadar Sahara. Ma'anar ita ce, dasa karin bishiyoyi zai taimaka wajen hana hamada, samar da ayyuka, inganta tsaro na abinci, da dawo da 'yan Afirka da suka rasa muhallinsu gida.

 Dubi kuma 

 Girbi ruwan sama a cikin Sahel

 Manazarta 

Rukuni:Shafuka masu fassarorin da ba'a duba ba