Ukutshatyalaliswa kwamahlathi kubhekisa kwilahleko yexesha elide okanye esisigxina yokugutyungelwa kwemigquma yomthi kunye nokuguqulwa kwalo mhlaba usetyenziselwa ezinye iinjongo. Ukuphulukana neepesenti ezili-10 kwetheyiphu kulifanele eli kota. I-United States ukugawulwa kwamahlathi kubangele ukutshatyalaliswa kwamahlathi angama-virgin ngu Iipesenti ezingama-75 ukusukela nge-1600. Ngo-2015, 33.9% wommandla womhlaba uwonke wawuphantsi kwamahlathi, isisiseko seprayimari, esihlaziya ngokwendalo kunye neminye imihlathi.
Oonobangela bokutshatyalaliswa kwamahlathi eUnited States
Ngo-1630, phantse ama-46% omhlaba e-US wawunamahlathi ngoqikelelo luka Isebe lezoLimo laseMelika (iphepha 5). Zininzi izinto ezibangela ukugawulwa kwamahlathi e-United States, kunye nakwamanye amazwe.
Amanqaku afanelekileyo- Amanqaku oNgcoliseko loMhlaba
- Imifanekiso yeZiphumo zokuFudumala kweHlabathi
- Imifanekiso yeMicimbi yangoku yezeNdalo
Izizathu zemali
Izizathu ezininzi zibandakanya imali. Abantu abaninzi abahlala kwimimandla enamahlathi aphezulu batsaleleka kwimali eninzi yokufumana amalungelo okugawula imihlaba yabo. Oku kwenzeka kuzo zonke iindawo zaseMelika. Umnini-mhlaba akunyanzelekanga ukuba abe ne-acreage ebalulekileyo ukuze asondele kubo abagawuli bemithi. Iihektare ezimbalwa ezinamahlathi zinokuvelisa iinkuni ezininzi kulogger onamava.
Kanye a ukugawulwa kwemithi Inkampani igawula amahlathi indawo, umnini mhlaba ngoku uneehektare ezininzi zomhlaba ocacileyo. Kwakhona, ngenxa yemali, umnini-mhlaba angazithengisa ezi iihektare kubaphuhlisi bezakhiwo ezitsha zezindlu. Ukusasazeka kwedolophu ayisiyonto nje yezixeko ezikhulu zeedolophu. Kwenzeka kwiindawo ezahlukeneyo emaphandleni aseMelika, kananjalo.
Ukucoca iiNjongo zeFama
Amafama ayakuxabisa ukucocwa kweehektare zawo ezinamahlathi. Banokuwusebenzisa lo mhlaba usandul 'ukucocwa ngeenjongo zezolimo, nokuba batyale izityalo kwaye bavune izibonelelo kwezo zivuno okanye bavumele ingca ukuba ikhule ngenjongo yokuhlwayela. Amafama agxile kwiinkomo angasebenzisa lamadlelo asandul 'ukwenziwa emhlambini wawo. Akumangalisi ukuba ngo-2012, kwaqikelelwa ukuba I-80% yokugawulwa kwamahlathi kwihlabathi liphela kwenzeka ukwenza indlela yeefama. Ezolimo yayisesona sizathu siphambili sokugawulwa kwamahlathi nango-2016 ngokwe Ukutya kunye noLimo lweZizwe eziManyeneyo (i-FAO).
Izityalo ezihlaselayo kunye nezinambuzane
Izityalo ezihlaselayo kunye nokufa kwemithi ngenxa yokuhlaselwa zizinambuzane nazo zithatha inani labo kumanani emithi. Umzekelo, iFlorida inengxaki yeengxelo ezingafunekiyo zeMelaleuca Izixhobo zeHlathi zaseMelika, ingxelo ka-2012 (FSR) yi-USDA (iphe. 11). Ukufa ngenxa yomphungane we ntaba kubuyisele umva ukukhula ngomthi ngama-48% kwiingingqi ze Rocky Mountain ukusukela ngo 2007 (FSR, pg. 26).
Iziphumo zokuGawulwa kwamahlathi
Imithi inefuthe kwimozulu. Uninzi lomntu wonke luyazi ukuba izityalo zinceda ukuvelisa ioksijini emoyeni ngeendlela ze ifotosinthesis . Ukutshatyalaliswa okungakumbi okwenziwa kumahlathi ehlabathi, i-oksijini encinci ikhutshwa kwakhona emoyeni. Oku kubangela utshintsho kumoya, oko ke kuchaphazele imeko yezulu.
Imo iyatshintsha
Ukugawulwa kwamahlathi sesinye sezizathu eziphambili zokutshintsha kwemozulu, njengoko iigesi zokugcina izityalo ezifana necarbon dioxide ethi ifunxwe yimithi ngexesha lefotosinthesisi izenza ezizezona zibalaseleyo icarbon sinks . Xa le mithi ingekho, icarbon dioxide ayisenakususwa kwiatmosfera, inyuke ubushushu bukazwe lonke .
Ukutshatyalaliswa kwamahlathi, okukhupha I-20% yokukhutshwa kwegesi eluhlaza (GHG), linoxanduva lokunikela nge-GHG engaphezulu kunezibaso ezitshisayo. Utshintsho lokusetyenziswa komhlaba olulandelayo njengolwezolimo olukhupha ezinye iigesi zegreenhouse ezinjenge-nitrous oxide kunye ne-methane, ngenxa yokusetyenziswa kwesichumiso kongeza enye i-20%. Oku isiphumo esongezelelweyo Kufuneka kulungiswe nokugawulwa kwamahlathi, lumkisa izazinzulu.
Utshintsho lomhlaba
Amahlathi ubuchule obungathethekiyo bokunceda ukukhusela umhlaba ongaphezulu kunye nezakha mzimba ezibalulekileyo. Ziyakhusela ngokuchasene nokhukuliseko lomhlaba kwaye zigcina umhlaba womelele. Kuqatshelwe ukuba ngokunyuka kwamahlathi kugawula, iqondo lokuhamba komjelo lonyukile.
Impembelelo kwiiNdalo zeNdalo
Ukutshatyalaliswa kwamahlathi kunefuthe Iindawo zokuhlala zendalo . Emahlathini, kuhlala iintlobo ngeentlobo zezilwanyana. Ngokulahleka kwamakhaya abo, kufuneka bafuduke. Ukufudukela kwabo kuhlala kubandakanya ukuhlala kwiindawo ezinabantu abaninzi, kubandakanya iidolophu nezixeko. Oku kwenzakalisa yonke i-ecosystem.
Ubungakanani bokutshatyalaliswa kwamahlathi eMelika
Amahlathi anokuhlelwa njengamahlathi agciniweyo, i-timberland kunye namanye amahlathi ayachaza Iinyani zasehlathini zase-U.S. Kunye neNkcubeko yezeMbali (i-FIA) . Amahlathi agciniweyo abandakanya iipaki zikarhulumente kunye nezomdibaniso ezibekelwe bucala ukulondolozwa, kwaye ziya kusokola ukunciphisa amahlathi. Uninzi lwazo lujolise entshona apho i-11% yazo ifunyenwe, kwaye ubuncinci empuma ine-3% kuphela yeepaki (i-FIA, iphe. 6, 7). I-Timberland egawuliweyo isasazwa ngokulinganayo kuyo yonke indawo e-U.S, kwaye amanye amahlathi aquka ukukhula ngokukhawuleza kwe-spruce e-Alaska kunye ne-pine-juniper entshona (i-FIA, iphe. 7).
Ihlathi lezobugcisa ithi indawo yehlathi eMelika 'ibizinzile phantse iminyaka eli-100'. Nangona kunjalo, ngokuka Ihlathi leHlabathi Jikelele I-USA ikwindawo yesine emhlabeni, ilahleko malunga nezigidi ezingama-29 zehektare phakathi ko-2001-2014.
Ukugawulwa kwamahlathi ngokugawulwa kwemithi nangokucocwa komhlaba kuyaqhubeka, kodwa kuye kwehla nge-17% ukusukela ngo-2006 ukuya ku-2011 ngokwe-FSR (iphepha lama-28). Kumthi osikiweyo i-65% ngumthi othambileyo kwaye i-35% ngumthi onzima. Umzantsi ubala i-63% yokususwa kwemithi kuzwelonke, ebisetyenziselwa umgubo, iinkuni zokubasa kunye neplywood (iphepha lama-29).
Amazwe aneelahleko ezinkulu
IDelaware ibonakalise ngaphezulu kwe-5% yelahleko yamahlathi ngo-2012 ngokwe-FSR ngenxa yokususwa (iphe. 14). Uhlalutyo lwehlabathi eqhutywa kwangaxeshanye ngokusekwe kwimifanekiso yesathelayithi kufunyaniswe ukuba ingingqi yoMzantsi-mpuma eMelika yenye yezona ndawo zisetyenziswa kakhulu eMelika.
Kumazwe aseFlorida, eSouth Carolina, naseAlabama, kukho i-30% yotshintsho kusetyenziso lomhlaba. Kweminye imimandla apha kugawulwa imithi, kwezinye ziyaphinda zitshintshwe, ukanti kweminye kugawulwa kutyalwe eminye, ukuze imithi apha ibe sisityalo. I-Alabama ikwabonakalise ukulahleka kwehlathi ngenxa yeqhwithi elabetha ngo-2011.
Amazwe aneNdawo yeHlathi eyandileyo
Kwelinye icala, kukho iindawo ezibonisa imeko elungileyo apho indawo yehlathi inyuke ngokuhamba kweminyaka, ngenxa yokutyala kwakhona. I-USA ikwindawo yesibini kwihlabathi ngokwenzuzo yemithi. I-Nebraska ibonisa ngaphezulu kwe-25% ye-regrowth, i-Oklahoma yabona ukunyuka kwama-20-25% kwindawo yehlathi, kunye ne-Texas, Kansas, kunye ne-South Dakota yafumana i-10-20% kumhlaba wehlathi (FSR, iphe. 14).
I-Alaska ixhaphake kakhulu
Omnye ummandla oshiyekileyo ungathintekiyo eUnited States lihlathi elineentaba kumantla eAlaska. I-Boreal ibhekisa kwimithi e-coniferous (umsedare, umsipres kunye nesoloko iluhlaza). Amashumi amabini anesithandathu eepesenti amahlathi aseAlaska agciniwe kwaye kufuneka ahlale engenakuguqulwa iminyaka emininzi, ezayo (FSR, iphe. 17).
Ithemba ngenxa yokuTshala kwakhona
Kwakhona, amahlathi amaninzi ayatyalwa. Isidingo somhlaba wehlathi siye saziwa ngokubanzi kulo lonke elaseMelika, kwaye abezendalo kuyo yonke indawo babeka ngakumbi lo mbandela. Kwenziwa iinzame zokuphindaphinda amahlathi anciphayo nokubuyisela indawo yokuhlala elahlekileyo. Kufunyenwe ukuba ukugawulwa kwamahlathi kuye kwanegalelo kubushushu bomhlaba, kwaye kufuneka kumiswe ukuze kuyekwe ukwenzakalisa okusingqongileyo.
Nangona amahlathi ephinda atyalwe, ayizukulungisa yonke into. La mahlathi atshintshiweyo anesakhiwo kunye nobume obahlukileyo kunobo bokuqala. Nangona kunjalo, ukutyala kwakhona kuyayandisa indawo yehlathi. Ngo-2011, bekukho ukwanda ngokubanzi kwindawo yehlathi lase-USA malunga ne-1% ukusukela ngo-2007, kwaye indawo yamahlathi iyaqhubeka nokukhula (FSR, iphe. 14). Ngexesha, ukuba ziyekwe zodwa, ziya kukhula ziye kumahlathi amadala akhulayo.
Guqula amahlathi aseU.S
Ukutshatyalaliswa kwamahlathi ngokungathandabuzekiyo kuya kuze kuphele. Iinkuni ezivela emithini zihlala zifuneka kumthombo wokwakha. Abantu bafudumeza amakhaya abo ngomthi. Ngumthombo wexabiso eliphantsi. Ngelixa iinkuni ziya kuqhubekeka zisetyenziselwa izinto ezahlukeneyo, izixa ezivuniweyo zinokuncitshiswa. I-United States ukugawulwa kwamahlathi kunokuzijika ngokulula.
