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Sosiale wetenskappe: aardrykskunde

Graad 8

Natuurlike hulpbronne

Module 9

Mariene bronne en die kus

Mariene Bronne

  • Die oseane bedek meer as twee derdes van die aardoppervlakte en speel ‘n sleutelrol in die hidrologiese siklus, die chemiese werking van die atmosfeer en die vorming van die klimaat en weer. Hoewel die oseane groot is, is hul eintlike biologiese rykdom gekonsentreer langs kuslyne, by riviermondings en op die relatief smal kontinentale banke tot op ‘n diepte van ongeveer 200 m. Hierdie gebied bevat die groot visvelde wat 80 persent van die wêreld se vis oplewer en een van die vernaamste voedselbronne vir miljoene mense is. Suid-Afrika is die wêreld se 24ste grootste visprodusent en meer as 90 persent van die jaarlikse vangs kom van die hoogs produktiewe koue waters van die Weskus.
  • Tot dusver is daar nog weinig formele pogings aangewend om die see veeldoenig te benut. Vroeëre en bestaande regulasies is hoofsaaklik gemik op die kommersiële ontginning van mariene bronne. Nie-volhoubare visvangste hou die grootste bedreiging in vir lewende mariene bronne. Baie van hierdie visvelde is in die verlede oorontgin en sommige visstapels, soos die sardyne langs die Namibiese kus, het nog nie herstel nie. In ‘n poging om visbronne volhoubaar wyse te benut, het die Suid-Afrikaanse owerhede ‘n kwotastelsel binne ‘n Totale Toelaatbare Vangs (TTV) vasgestel vir kommersiële spesies, aangevul met geslote seisoene en groottebeperkings.
  • Onder Suid-Afrika se ou bestel is gemeenskappe se tradisionele toegang tot mariene bronne geleidelik van hulle ontneem, deurdat voorkeur gegee is aan groter maatskappye wat deur vermoënde aandeelhouers beheer is.

  • Enkele jare gelede het die Wes-Kaapse regering besluit om d.m.v. wetgewing viskwotas in te stel. Dit het tot groot teenkanting onder verskillende gemeenskappe gelei. Hier volg twee van talle response in die plaaslike koerante.

Vis op drumpel van uitwissing

Ek lees met skok in Die Burger van 18 April van die ineenstorting van lynvis in ons waters. Agt lyn-visspesies word tans vinniger gevang as wat hulle kan teel.

Volgens die verslag van dr. Marc Griffiths van Mariene en Kusbestuur sal lisensiehouers verminder moet word om die visbedryf te red.

Die verslag meld dat galjoen, silwer-kabeljou, witsteenbras, witstompneus en donkerkabeljou vinniger gevang word as wat hulle kan teel en dat die elf reeds oorbenut is. Die dageraad het glo al feitlik verdwyn.

Om die visbronne van totale uitwissing te red sal strenger maatreëls toegepas moet word.

Opofferinge sal deur die rots- en strandhengelaars sowel as die strandnet- en treiler-eienaars gedoen moet word.

Verder sal die Regering ernstig daaraan moet dink om meer wetstoepassers aan te stel om die regulasies op die bewaring van Mariene en Kusbestuur afdwingbaar te maak, en dit behoorlik toe te pas.

Buitelandse vistreilers sal verbied moet word om binne 200 km gebiedswaters van Suid-Afrika vis te vang, en geen viskwotas moet aan hulle toegestaan word nie.

Strandnet-eienaars moet vir minstens twee jaar verbied word. Indien hulle wel toegelaat word om vis langs die kus te vang, moet hul nette drasties na 100 m verkort word, sonder ‘n sak in die net. Strandnette roei talle ondermaat-visse uit.

Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
how can I make nanorobot?
Lily
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
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Source:  OpenStax, Aardrykskunde graad 8. OpenStax CNX. Sep 11, 2009 Download for free at http://cnx.org/content/col11035/1.1
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