Rashin bambancin halittu

Rashin bambancin halittu yana faruwa ne lokacin da nau'in shuke-shuke ko dabbobi suka ɓace gaba ɗaya daga Duniya (halaka) ko kuma lokacin da akwai raguwa ko ɓacewar nau'in a cikin takamaiman yanki. Rashin bambancin halittu yana nufin cewa akwai raguwa a cikin bambancin halittukan halittu a cikin wani yanki. Ragewa na iya zama na wucin gadi ko na dindindin. Yana da na wucin gadi idan lalacewar da ta haifar da asarar za a iya juyawa a lokaci, misali ta hanyar Maido da muhalli. Idan wannan ba zai yiwu ba, to raguwar ta dindindin ce. Dalilin mafi yawan asarar halittu shine, gabaɗaya, ayyukan ɗan adam waɗanda ke tura iyakokin duniya da nisa. Wadannan ayyukan sun hada da lalacewar mazaunin  (alal misali sare daji) da kuma karfafa Amfani da ƙasa (alal misali noma monoculture).   Ƙarin wuraren matsala sune gurɓataccen iska da ruwa (ciki har da gurɓatawar abinci mai gina jiki), yawan amfani, nau'o'in mamayewa  da Canjin yanayi. 

Masana kimiyya da yawa, tare da Rahoton Bincike na Duniya kan Biodiversity da Ayyukan Ecosystem, sun ce babban dalilin asarar halittu shine karuwar yawan mutane saboda wannan yana haifar da Yawan jama'a da yawan amfani. Sauran ba su yarda ba, suna cewa asarar mazaunin ya samo asali ne daga "ci gaban kayayyaki don fitarwa" kuma yawan jama'a ba su da alaƙa da amfani gaba ɗaya. Mafi mahimmanci shine bambancin dukiya tsakanin da cikin ƙasashe. A kowane hali, duk asarar halittu na zamani an danganta shi da ayyukan ɗan adam.

Canjin yanayi wani barazana ne ga Bambancin halittu na duniya. Misali, coral reefs - wanda shine hotspots na biodiversity - za a rasa a shekara ta 2100 idan dumamar duniya ta ci gaba a halin yanzu. Duk da haka, lalacewar mazaunin gaba ɗaya ne (sau da yawa don fadada aikin gona), ba canjin yanayi ba, wanda a halin yanzu shine mafi girman direba na asarar halittu. Dabbobi masu mamayewa da sauran rikice-rikice sun zama ruwan dare a cikin gandun daji a cikin shekarun da suka gabata. Wadannan suna da alaƙa kai tsaye ko a kaikaice da canjin yanayi kuma suna iya haifar da lalacewar yanayin gandun daji.

Kungiyoyin da ke kula da muhalli suna aiki na shekaru da yawa don dakatar da raguwar halittu masu yawa. A zamanin yau, manufofi da yawa na duniya sun haɗa da ayyukan don dakatar da asarar halittu masu yawa. Misali, Yarjejeniyar Majalisar Dinkin Duniya kan Bambancin Halitta tana da niyyar hana asarar bambancin halittu da kuma kiyaye wuraren jeji. Koyaya, rahoton Shirin Muhalli na Majalisar Dinkin Duniya na 2020 ya gano cewa yawancin waɗannan ƙoƙarin sun kasa cimma burinsu. Misali, daga cikin burin halittu iri-iri 20 da Aichi Biodiversity Targets ya tsara a cikin 2010, shida ne kawai aka "ƙasa" zuwa shekarar 2020 .

Wannan lalacewar duniya da ke gudana ana kiranta lalacewar holocene ko lalacewar taro ta shida.Kashewa ta shida.

 Ƙididdigar duniya a duk nau'o'in 
Yawan asarar halittu na duniya a halin yanzu an kiyasta ya zama sau 100 zuwa 1000 mafi girma fiye da (na halitta) ƙimar lalacewar baya, da sauri fiye da kowane lokaci a tarihin ɗan adam,   kuma ana sa ran girma a cikin shekaru masu zuwa.   Hanyoyin halaka da sauri na kungiyoyin dabbobi daban-daban kamar dabbobi masu shayarwa, tsuntsaye, dabbobi masu rarrafe, amphibians, da kifi sun jagoranci masana kimiyya su ayyana rikicin halittu na yanzu a cikin yanayin ƙasa da na teku.

A shekara ta 2006, an rarraba wasu nau'o'in halittu da yawa a matsayin masu wuya ko masu haɗari ko barazanar; Bugu da Rare, masana kimiyya sun kiyasta cewa miliyoyin nau'o-in halittu Yana cikin haɗari waɗanda ba a san su ba.

Har ila yau, sare daji yana taka muhimmiyar rawa a cikin asarar halittu masu yawa. Fiye da rabin halittu masu yawa a duniya an shirya su a cikin gandun daji na wurare masu zafi. Yankunan da ke fuskantar asarar halittu masu yawa ana kiransu wuraren da ke cike da halittu masu ban sha'awa. Tun daga shekara ta 1988 hotspots sun karu daga 10 zuwa 34. Daga cikin jimlar wurare masu zafi 34 a halin yanzu, 16 daga cikinsu suna cikin yankuna masu zafi (kamar yadda na 2006).  Masu bincike sun lura a shekara ta 2006 cewa kashi 2.3% ne kawai na duniya ke rufe da wuraren asarar halittu, kuma kodayake ƙananan kashi ne kawai na duniyar ke rufe da hotspots, yana karɓar bakuncin babban kashi (50%) na nau'in tsire-tsire.

A cikin 2021, kusan kashi 28 cikin 100 na nau'in 134,400 da aka tantance ta amfani da ka'idodin IUCN Red List yanzu an jera su a matsayin masu barazanar halaka - jimlar nau'in 37,400 idan aka kwatanta da nau'in 16,119 da ke fuskantar barazana a cikin 2006.

Wani binciken da aka yi a shekarar 2022 wanda ya binciki masana sama da 3,000 ya gano cewa "hasarar halittu da tasirinsa na iya zama mafi girma fiye da yadda aka yi tunani a baya", kuma ya kiyasta cewa kusan kashi 30% na jinsunan "an yi barazana a duniya ko kuma an fitar da su tun daga shekara ta 1500." 

Binciken da aka buga a 2023 ya gano cewa, daga cikin nau'in 70,000, kusan kashi 48% suna fuskantar raguwar yawan jama'a saboda ayyukan ɗan adam, yayin da kashi 3% kawai ke ganin karuwar yawan jama'ar.

 Hanyoyi don ƙididdige asarar 
Masana ilimin halittu sun bayyana bambancin halittu a matsayin "dukkanin kwayoyin halitta, jinsuna da yanayin halittu na yanki".   Don auna yawan asarar halittu don wani wuri, masana kimiyya sun yi rikodin wadatar jinsuna da bambancin sa a tsawon lokaci a wannan yanki. A cikin ilimin muhalli, yalwar gida shine wakilcin dangi na jinsin a cikin wani tsarin halittu. Yawancin lokaci ana auna shi azaman yawan mutanen da aka samu a kowane samfurin. Rabin yalwar jinsin daya zuwa daya ko wasu jinsunan da ke zaune a cikin yanayin halittu ana kiransa yalwar jinsunan dangi. Dukkanin alamun suna da dacewa don lissafin bambancin halittu.

Akwai nau'ikan halittu daban-daban. Wadannan suna binciken ma'auni daban-daban da kuma tsawon lokaci. Biodiversity yana da ma'auni daban-daban da ƙananan fannoni (misali bambancin phylogenetic, bambancin jinsuna, Bambancin kwayoyin halitta, Bambancin nucleotide). 

Tambayar asarar kuɗi a yankuna masu iyaka sau da yawa batun muhawara ne.

 Bincike ta hanyar rayuwa 

 Dabbobin daji gabaɗaya 
Wani bincike na Oktoba 2020 da Swiss Re ya gano cewa kashi ɗaya cikin biyar na dukkan ƙasashe suna cikin haɗarin Rushewar yanayin halittu sakamakon lalacewar mazaunin ɗan adam da ƙaruwar asarar namun daji. Idan ba a juyar da waɗannan asarar ba, cikakkiyar rushewar yanayin halittu na iya biyo baya.

A cikin 2022, Asusun Kula da namun daji na Duniya ya ba da rahoton  matsakaicin raguwar yawan jama'a na 68% tsakanin 1970 da 2016 don nau'in dabbobi 4,400 a duk duniya, wanda ya ƙunshi kusan yawan mutanen da aka sa ido 21,000. 

 Manazarta 
Rukuni:Shafuka masu fassarorin da ba'a duba ba