Kusaziva Hakusi Kufara: Chidzidzo Chitsva PaChimiro CheKusaongororwa Kwehove Yehove Inosimbisa Kutyisidzirwa Kwepasirese Kunoitwa NeKuredza Hove.

naKenneth Stump, Ocean Policy Fellow kuThe Ocean Foundation

Kuredza hove (uye kushandiswa kwemidziyo inoparadza hove) kunowanzotaurwa seimwe yezviviri zvakanyanya kutyisidzira mhuka dziri mugungwa. Overfishing inoitika apo hove inobvisa hove kubva muhuwandu nekukurumidza kupfuura iyo huwandu hunogona kuzvizadza pachayo - mushoko, kubata hove kwakawandisa. Kana zvikasakurumidza kudzorwa, kubata hove kwakanyanyisa kunotungamirira kukuparadzwa kwehove pakupedzisira uye kuparara kwehove. Vesainzi uye vatarisiri vehove vanovavarira kuona kuti chiverengero chavagari vemo chemarudzi api neapi chinofanira kuva chakakura sei kutaura kuti hachireveki zvakanyanyisa.

Kune masheya akanyatso dzidza akaongororwa nesainzi, zvinokwanisika kuongorora mamiriro emasheya maererano nemaitiro ekuredzesa hove ayo anobva pakugona kwechigadzirwa chakapihwa kuburitsa goho rinogoneka (MSY). Uchishandisa aya akajairwa matanho ekuchengetedza hove, Dr. Boris Worm et al. (2009) vakaona kuti 63% yehove dzakaongororwa pasi rose dzine saizi yekuberekesa ("biomass," inotaridzwa se "B") pazasi pedanho rinofungidzirwa kugadzira MSY (B/Bmsy <1), ukuwo imwe ongororo yakaitwa ne iyo FAO (2010) yakagumisa kuti 32% yezviyo zvakaongororwa pasi rose zvakanyanyisa (B/Bmsy <0.5).

Muchidimbu, hove zhinji dzakaongororwa pasi rose dzinoshandiswa zvizere kana kuti dzakanyanya. Asi chete ~ 20% yehove dzepasi rose dzinobatwa (dzakashumwa kumhara) dzinobva kumarudzi akaongororwa. Zvakadini nechimiro chezviuru zvehove dzisina data, dzisina kuongororwa dzinotora 80% kana kupfuura yehove dzepasi rose dzinobatwa gore rega rega?

UC Santa Barbara's Christopher Costello nevamwe vaanoshanda navo vachangobva kuburitsa chidzidzo chitsva chechimiro chepasi rose-varombo masheya mune online edition yeSainzi (Gunyana 27, 2012). Vachishandisa marekodhi ekumhara aripo uye nzira dzekuongorora dzisina kunanga, vanyori vechidzidzo chitsva vanogumisa kuti mazhinji ehove idzi angangove akadzikira zvakanyanya uye mukuderera zvakanyanya:

Chikamu che64% chezvitoro zvehove zvisina kuongororwa zvine hupfumi huri pasi peBmsy (B/Bmsy <1), izvo zvakangofanana nekuderera kwechikamu che60-70% pazvitoro zvakawanda.
18% yezviyo zvisina kuongororwa zvakaputsika (B / Bmsy <0.2) - chiyero chekuderera zvakanyanya zvokuti huwandu hwehove hunogona kunge huri chikamu chiduku chekukura kwayo kwechisikigo, kusina kureveswa.

Kuderera kwehuwandu hwehove zhinji (yakaderera B/Bmsy) kune mhedzisiro yekuchengetedzeka kwekudya: goho rehove riri pasi pezvazvinogona kana masheya akabvumidzwa kudzoreredza kusvika pamwero unozoburitsa MSY. Sezvo mazhinji ehove dzisina kuongororwa idzi dziri munyika dzine urombo uye dzichiri kusimukira, nzira dzehutungamiriri dzekuvaka patsva masheya dzinovimba nehutongi hwakasimba uye kugona kwekutarisa hazvigone kushanda. Asi Costello nevamwe vaanoshanda navo vanopawo tariro yekuti mazano matsva anosanganisa kodzero dzevashandisi venzvimbo (TURFs), masangano ekubata hove, uye nzvimbo dzakachengetedzwa dzemugungwa dzinogona kudzoreredza huwandu uhu hune hutano, hunobudirira - kana danho rekukurumidza rikatorwa kudzoreredza kuderera. .

MuUS, kuvandudzwa kwemutemo wenyika wehove muna 1996 na2006 kwakaderedza kubatwa kwehove zvakapfuura nechidimbu nehafu kubva National Marine Fisheries Service yakatanga kuburitsa mishumo yemamiriro epagore mukupera kwema1990, sezvakaratidzwa muFig. 1. Muna 2011, US. hove dzekutengesa dzakanyora hove dzepamusoro mumakore gumi nemanomwe, izvo zvinoratidza kuti kuedza kumisa kubatwa kwehove zvakapfurikidza uye kuvakazve hove dzakawandisa kuri kutanga kubhadhara mumatunhu akawanda (asi kwete ose) enyika.

Asi inenge hafu yezvose zvakachengetwa mumvura yeUnited States haisati yaongororwa uye chidzidzo chakaitwa naCostello et al. inoona kuti mamwe eaya masheya asina data anogona kunge aine chimiro chakashata seaya ari munyika dzichiri kusimukira. Semuenzaniso, hove dzakawanda dzereef dzakadai segroupers muSouth Atlantic neGulf yeMexico, marudzi akawanda e shark, halibut muNew England, kutaura zvishomanana, anozivikanwa kuti akapera kare kunyange zvazvo asina kuongororwa zviri pamutemo.

Migumisiro yokuredza hove haigumiri pakuderera kwerudzi rumwe norumwe rwehove. Kupera kwezvipenyu zvakakosha zvekutengesa mukukurumidza kutevedzana kunogona kukonzeresa trophic cascades inoshandura chimiro chewebhu chikafu nekufamba kwenguva, ichigadzira zvisingatarisirwe mhedzisiro,. Mhedzisiro yezvakatipoteredza yekuredza hove haiwanzo kutariswa zvakanyanya mukuverenga kwakajairwa kwekuredza hove, asi kumwe ongororo ichangobva kuitwa neNOAA's Northeast Fisheries Science Center yakagumisa kuti dunhu reNew England rakasangana nehove dzemhando yepamusoro nekuda kwekuwanda kwekuredza hove uye nzira dzekukohwa dzinosarudzwa. yakakonzera shanduko muhuwandu hwehove kubva kuhurongwa hunotongwa nemhando dzakadai sekod kuenda kune imwe iri kuwedzera kudzorwa nehove diki dzepelagic dzine mutengo wakaderera senge herring neelasmobranch marudzi (shark diki uye skates). Migumisiro yakafanana yakaonekwa mune dzimwe nzvimbo dzomugungwa dzakaredzwa zvikuru, dzakadai seNorth Sea yeEurope kana kuti makorari eCaribbean.

Sechidzidzo chitsva chakaitwa naCostello et al. inoratidza, zviuru chaizvo zvezvipenyu zvinokanganiswa nokuredza munyika yose uye akawanda acho anoratidzika kuva ari kuderera. Mhedzisiro isingatarisirwe yekukanganisa kwakapararira kwakadaro pazvipenyu zvegungwa hazvizivikanwe zvizere, asi kusaziva hakusi mufaro. Kuredza hove kwakawandisa kunotyisidzira kuchengetedzwa kwechikafu uye hupfumi hwehove hwemunharaunda, asi kuedza kuchengetedza kugadzirwa kwehove dzemusango sechikafu chevanhu kuchakundikana kana tikaregeredza basa rinoitwa nemarudzi ese aya mumhepo. . Sezvo masayendisiti nevatungamiriri vehove vanorwisana nenzira dzokupedza nadzo denda rokuredza hove, vanofanira kurangarira idzi fungidziro dzemhoteredzo yemhoteredzo mukuverenga kwavo kuti kuredza kwakawanda sei. Zvinogona kureva kubata hove shoma, asi imwe nzira inogona kunge isiri kubata hove zvachose.

Sources:

Christopher Costello, Daniel Ovando, Ray Hilborn, Steven D. Gaines, Olivier Deschenes, naSarah E. Lester (2012), Mamiriro uye Solutions for the World's Ussesed Fisheries, Science Online, September 27, 2012.

NOAA Northeast Fisheries Science Center (2009), Ecosystem Status Report yeNE Continental Shelf Large Marine Ecosystem.

Boris Worm et al. (2009), Kuvakazve Global Fisheries, Sayenzi 325: 578-585.