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Differential urbanisation and regional policy : the case of the Gauteng Functional Metropolitan Region / Johannes Ernst DrewesDrewes, Johannes Ernst January 2000 (has links)
Streekontwikkelingsbeleid en differensiële verstedeliking is twee
fundamentele temas binne die ruimtelike beplanningsveld.
Streekontwikkelingsbeleid is veral sedert die Tweede Wêreldoorlog in
Europa geïmplementeer, waar regerings besef het dat die vryemarksisteem
nie noodwendig optimale ekonomiese groei op streekvlak
verseker nie.
Doelwitte
Die primêre doelwit van hierdie studie is die integrering van effektiewe en
volhoubare streekontwikkelingsbeleid met die konsep van differensiële
verstedeliking, ten einde 'n effektiewe stedelike bestuursmeganisme daar
te stel. Sekondêre doelwitte sluit in:
* om die beginsels en doelwitte van streekontwikkelingsbeleid en
streekontwikkelingsinstrumente te bepaal;
* die analisering van Suid-Afrikaanse streekontwikkelingsbeleid in terme ·
van bogenoemde klassifikasie;
* ondersoek na die teoretiese en praktiese toepassings van die
differensiële verstedelikingsmodel;
* om die geldigheid van die differensiële verstedelikingsmodel te bepaal
in die Gauteng Funksionele Metropolitaanse Streek; en
* om relevante streekontwikkelingsbeleid te integreer met sosio-ekonomiese
tendense in 'n stedelike sisteem, met spesifieke verwysing
na die Gauteng Funksionele Metropolitaanse Streek.
Metodiek
Die rasionaal vir die formulering van streekontwikkelingsbeleid word in
Hoofstuk Twee beskryf. Regerings en ander streekowerhede formuleer
streekontwikkelingsbeleid ten einde spesifieke doelstellings te behaal.
Hierdie doelstellings verander met tyd en is gewoonlik streekspesifiek.
Die relevante owerheid of instansie neem 'n besluit in terme van
bogenoemde fundamentele benaderingswyses, waarna 'n keuse ten opsigte
van spesifieke beleidsopsies en -instrumente geneem word. Hoofstuk Drie
beskryf laasgenoemde beleidsinstrumente asook meer gedetailleerde
beleidselemente soos wat dit op projekvlak geïmplementeer word.
In Hoofstuk Vier word die geskiedkundige implementering van
streekontwikkelingsbeleid in Suid-Afrika en spesifiek vir die Gauteng- en
omliggende streek, ondersoek. Die Gauteng Funksionele Metropolitaanse
Streek het reeds 'n gevorderde vlak van stedelike ontwikkeling binne die
Suid-Afrikaanse konteks bereik en was histories instrumenteel in die
implementering van streekontwikkelingsbeleid.
'n Sentrale tema in hierdie studie, is die beginsel dat stedelike komplekse
'verouder' met tyd. Soos wat hierdie stedelike komplekse ontwikkel, kan
verskillende migrasie- en ekonomiese produksiepatrone onderskei word in
dieselfde areas, maar die patrone is georiënteer in verskillende rigtings en
gebaseer op verskillende motiverings. Hierdie tendense word deur die
differensiële verstedelikingsmodel in Hoofstuk Vyf aangespreek.
Na die afskaffing van diskriminerende wetgewing, is die verwagting dat
die bevolkingsgetalle van groter stedelike komplekse vir 'n aansienlike
tydperk steeds sal toeneem. In Hoofstuk Ses word hierdie
migrasieprosesse, asook veranderende produksiepatrone in die
studiegebied ontleed, gebaseer op die resultate van die mees onlangse
sosio-ekonomiese opnames.
Bevindings
Uit die studie blyk dit duidelik dat streekontwikkelingsbeleid steeds
geïmplementeer word in reaksie op bepaalde ongelykhede in 'n streek.
Laasgenoemde verwys gewoonlik na hoe vlakke van werkloosheid en
kwynende ekonomiese sektore in sekere stede. Die voorstel in die studie
is die vroegtydige formulering van streekontwikkelingsbeleid vir al die
elemente binne die stedelike sisteem, gegewe die huidige
ontwikkelingsvlak in terme van die differensiële verstedelikingsmodel.
Hiervolgens kan sentra met toenemende ekonomiese- en bevolkingsgroei
vroegtydig geïdentifiseer en ontwikkeling bevorder word. Soortgelyk, kan
plekke met kwynende ekonomieë en bevolkingsgetalle ondersteun word in
die fase van stedelike groei.
Die sosio-ekonomiese profiel van die studiegebied, naamlik die Gauteng
Funksionele Metropolitaanse Streek, het in die studie bewys dat dit 'n
identifiseerbare ontwikkelings- of 'verouderingsroete' gevolg het sedert
die 1960s. Dit is ook duidelik in die studie dat die effektiwiteit van
streekontwikkelingsbeleid en die volhoubaarheid daarvan gewoonlik
omgekeer eweredig is aanmekaar: soos volhoubaarheid toeneem, neem
ekonomiese effektiwiteit af. Die voorgestelde integrering van
streekontwikkelingsbeleid en differensiële verstedeliking behoort hierdie
negatiewe tendens ten opsigte van effektiwiteit en volhoubaarheid om te
keer, ten einde toenemende volhoubaarheid en effektiwiteit te verseker in
die stedelike ontwikkelingsproses. / PhD (Town and Regional Planning), Potchefstroom University for Christian Higher Education, 2001
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2 |
Differential urbanisation and regional policy : the case of the Gauteng Functional Metropolitan Region / Johannes Ernst DrewesDrewes, Johannes Ernst January 2000 (has links)
Streekontwikkelingsbeleid en differensiële verstedeliking is twee
fundamentele temas binne die ruimtelike beplanningsveld.
Streekontwikkelingsbeleid is veral sedert die Tweede Wêreldoorlog in
Europa geïmplementeer, waar regerings besef het dat die vryemarksisteem
nie noodwendig optimale ekonomiese groei op streekvlak
verseker nie.
Doelwitte
Die primêre doelwit van hierdie studie is die integrering van effektiewe en
volhoubare streekontwikkelingsbeleid met die konsep van differensiële
verstedeliking, ten einde 'n effektiewe stedelike bestuursmeganisme daar
te stel. Sekondêre doelwitte sluit in:
* om die beginsels en doelwitte van streekontwikkelingsbeleid en
streekontwikkelingsinstrumente te bepaal;
* die analisering van Suid-Afrikaanse streekontwikkelingsbeleid in terme ·
van bogenoemde klassifikasie;
* ondersoek na die teoretiese en praktiese toepassings van die
differensiële verstedelikingsmodel;
* om die geldigheid van die differensiële verstedelikingsmodel te bepaal
in die Gauteng Funksionele Metropolitaanse Streek; en
* om relevante streekontwikkelingsbeleid te integreer met sosio-ekonomiese
tendense in 'n stedelike sisteem, met spesifieke verwysing
na die Gauteng Funksionele Metropolitaanse Streek.
Metodiek
Die rasionaal vir die formulering van streekontwikkelingsbeleid word in
Hoofstuk Twee beskryf. Regerings en ander streekowerhede formuleer
streekontwikkelingsbeleid ten einde spesifieke doelstellings te behaal.
Hierdie doelstellings verander met tyd en is gewoonlik streekspesifiek.
Die relevante owerheid of instansie neem 'n besluit in terme van
bogenoemde fundamentele benaderingswyses, waarna 'n keuse ten opsigte
van spesifieke beleidsopsies en -instrumente geneem word. Hoofstuk Drie
beskryf laasgenoemde beleidsinstrumente asook meer gedetailleerde
beleidselemente soos wat dit op projekvlak geïmplementeer word.
In Hoofstuk Vier word die geskiedkundige implementering van
streekontwikkelingsbeleid in Suid-Afrika en spesifiek vir die Gauteng- en
omliggende streek, ondersoek. Die Gauteng Funksionele Metropolitaanse
Streek het reeds 'n gevorderde vlak van stedelike ontwikkeling binne die
Suid-Afrikaanse konteks bereik en was histories instrumenteel in die
implementering van streekontwikkelingsbeleid.
'n Sentrale tema in hierdie studie, is die beginsel dat stedelike komplekse
'verouder' met tyd. Soos wat hierdie stedelike komplekse ontwikkel, kan
verskillende migrasie- en ekonomiese produksiepatrone onderskei word in
dieselfde areas, maar die patrone is georiënteer in verskillende rigtings en
gebaseer op verskillende motiverings. Hierdie tendense word deur die
differensiële verstedelikingsmodel in Hoofstuk Vyf aangespreek.
Na die afskaffing van diskriminerende wetgewing, is die verwagting dat
die bevolkingsgetalle van groter stedelike komplekse vir 'n aansienlike
tydperk steeds sal toeneem. In Hoofstuk Ses word hierdie
migrasieprosesse, asook veranderende produksiepatrone in die
studiegebied ontleed, gebaseer op die resultate van die mees onlangse
sosio-ekonomiese opnames.
Bevindings
Uit die studie blyk dit duidelik dat streekontwikkelingsbeleid steeds
geïmplementeer word in reaksie op bepaalde ongelykhede in 'n streek.
Laasgenoemde verwys gewoonlik na hoe vlakke van werkloosheid en
kwynende ekonomiese sektore in sekere stede. Die voorstel in die studie
is die vroegtydige formulering van streekontwikkelingsbeleid vir al die
elemente binne die stedelike sisteem, gegewe die huidige
ontwikkelingsvlak in terme van die differensiële verstedelikingsmodel.
Hiervolgens kan sentra met toenemende ekonomiese- en bevolkingsgroei
vroegtydig geïdentifiseer en ontwikkeling bevorder word. Soortgelyk, kan
plekke met kwynende ekonomieë en bevolkingsgetalle ondersteun word in
die fase van stedelike groei.
Die sosio-ekonomiese profiel van die studiegebied, naamlik die Gauteng
Funksionele Metropolitaanse Streek, het in die studie bewys dat dit 'n
identifiseerbare ontwikkelings- of 'verouderingsroete' gevolg het sedert
die 1960s. Dit is ook duidelik in die studie dat die effektiwiteit van
streekontwikkelingsbeleid en die volhoubaarheid daarvan gewoonlik
omgekeer eweredig is aanmekaar: soos volhoubaarheid toeneem, neem
ekonomiese effektiwiteit af. Die voorgestelde integrering van
streekontwikkelingsbeleid en differensiële verstedeliking behoort hierdie
negatiewe tendens ten opsigte van effektiwiteit en volhoubaarheid om te
keer, ten einde toenemende volhoubaarheid en effektiwiteit te verseker in
die stedelike ontwikkelingsproses. / PhD (Town and Regional Planning), Potchefstroom University for Christian Higher Education, 2001
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Migration patterns and survival of Busseola fusca larvae in maize plantings with different ratios of Bt and non-Bt seed / Jaco MaraisMarais, Jaco January 2014 (has links)
The high-dose/refuge strategy is used globally to manage insect resistance development in genetically modified crops with insecticidal properties (Bt crops). The “refuge in a bag” (RIB) strategy is also being considered for deployment against several pest species. Busseola fusca, the target pest of Bt maize in South Africa, evolved resistance to Cry1Ab proteins. The objective of this study was to determine whether migrating B. fusca larvae are effectively controlled using the RIB strategy. A field study with a single-gene event (Cry1Ab) and a “pyramid” event (Cry1A.105 + Cry2Ab2) was conducted in which the migration patterns of B. fusca larvae in plots with different seed mixture treatments were studied. The experiment consisted of five seed mixture ratios (5%, 10%, 15%, 20% non-Bt seed and 100 % non-Bt seed as control). Natural infestation was augmented by artificial inoculation with neonate larvae into the central non-Bt maize plant of each plot. Rate of larval survival and migration, measured in terms of increase in number of plants per plot that exhibited borer damage was recorded at weekly intervals until flowering. A laboratory study was conducted to determine larval growth and survival when simulating migration between Bt and non-Bt maize plants. A feeding experiment in which larvae were reared on different types of maize (Bt and non-Bt) was conducted and larval survival and mass recorded after a 7-day feeding period. The incidence of damaged ears, stem damage and damaged internodes per stem were recorded and relationships between these variables determined by means of correlation analyses. A review was conducted in order to identify and discuss similarities and differences between the high-dose/refuge and seed mixture strategies. This was done to determine which strategy would be the most appropriate insect resistance management (IRM) strategy against B. fusca. The rate of survival and migration of B. fusca larvae was significantly higher in the plots with maize expressing Cry1Ab and control plots, than in plots with the pyramid Bt event. Older larvae exhibited improved growth and survival in the laboratory experiment when they were transferred from non-Bt to Bt plants. Positive correlations were found between early and late season damage, although some weaker than others. Plants of the “pyramid event” suffered less late-season damage than those of the single-gene event. Since the increase in number of damaged maize plants over time is associated with migration of older and larger larvae, the observed tendencies may indicate that the assumed high-dose does not kill larvae above a certain developmental stage. The high-dose refuge strategy seems to be the better option for delaying resistance development. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
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Migration patterns and survival of Busseola fusca larvae in maize plantings with different ratios of Bt and non-Bt seed / Jaco MaraisMarais, Jaco January 2014 (has links)
The high-dose/refuge strategy is used globally to manage insect resistance development in genetically modified crops with insecticidal properties (Bt crops). The “refuge in a bag” (RIB) strategy is also being considered for deployment against several pest species. Busseola fusca, the target pest of Bt maize in South Africa, evolved resistance to Cry1Ab proteins. The objective of this study was to determine whether migrating B. fusca larvae are effectively controlled using the RIB strategy. A field study with a single-gene event (Cry1Ab) and a “pyramid” event (Cry1A.105 + Cry2Ab2) was conducted in which the migration patterns of B. fusca larvae in plots with different seed mixture treatments were studied. The experiment consisted of five seed mixture ratios (5%, 10%, 15%, 20% non-Bt seed and 100 % non-Bt seed as control). Natural infestation was augmented by artificial inoculation with neonate larvae into the central non-Bt maize plant of each plot. Rate of larval survival and migration, measured in terms of increase in number of plants per plot that exhibited borer damage was recorded at weekly intervals until flowering. A laboratory study was conducted to determine larval growth and survival when simulating migration between Bt and non-Bt maize plants. A feeding experiment in which larvae were reared on different types of maize (Bt and non-Bt) was conducted and larval survival and mass recorded after a 7-day feeding period. The incidence of damaged ears, stem damage and damaged internodes per stem were recorded and relationships between these variables determined by means of correlation analyses. A review was conducted in order to identify and discuss similarities and differences between the high-dose/refuge and seed mixture strategies. This was done to determine which strategy would be the most appropriate insect resistance management (IRM) strategy against B. fusca. The rate of survival and migration of B. fusca larvae was significantly higher in the plots with maize expressing Cry1Ab and control plots, than in plots with the pyramid Bt event. Older larvae exhibited improved growth and survival in the laboratory experiment when they were transferred from non-Bt to Bt plants. Positive correlations were found between early and late season damage, although some weaker than others. Plants of the “pyramid event” suffered less late-season damage than those of the single-gene event. Since the increase in number of damaged maize plants over time is associated with migration of older and larger larvae, the observed tendencies may indicate that the assumed high-dose does not kill larvae above a certain developmental stage. The high-dose refuge strategy seems to be the better option for delaying resistance development. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
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